Today, the image of a Hydro Power Plant is cemented in our heads as a giant dam with giant jet-type turbines. A stream of water of incredible volume passes through the spiral blades, rotating them and generating energy. We also imagine hydroelectric dams in a certain sense as regulators of the flow of rivers, which prevent them from overflowing or drying out depending on the weather. That is, no one squeezes out all the crumbs of potential and kinetic energy from every drop of water and does not endanger entire ecosystems and settlements. Although the latter does not apply to the communists.
When can I pick up everything?
Bieudron Hydroelectric Power Station
In cases where the construction of a dam and the operation of a hydroelectric power station has a minimal impact on the environment. A striking example of efficiency and environmental friendliness is the Swiss Biedron hydroelectric power station, built in 1993 and put into operation in 1998. The efficiency of this hydroelectric power plant is 92.37%, and its capacity reaches 1269 MW. For comparison, Dneproges has a capacity of 1569 MW, as well as a huge reservoir. Usually structures Bieudron Hydroelectric Power Station also owns a dam 700 m long, but the key difference in height, because the height of the Swiss dam is 285 m dam Dnieper -… 60 m
Dnieper Hydroelectric Power Station
This dam height leads to the fact that the calculated pressure is 1883 m That is, to get. a similar pressure will have to be installed on a water tower at the top of Hoverla and drilled at the foot of a mine 500 m deep. And the pressure at which the turbines operate is 200.5 atmospheres. The speed at which water enters the turbine is 192 m/s or Mach 0.56. Boeing is just 150 km/h faster. And with all this, the hydroelectric station spends only 25 cubic meters of water per second, 200 times less than the previously mentioned Dnieper hydroelectric station. And this is despite the fact that the Biedron Swiss HPP is only 20% less powerful than the Dnieper power plant.
The secret to efficiency
Unlike most low-pressure hydropower plants, Switzerland’s largest hydropower plant uses Pelton turbines. This is not a very new invention. It was designed by Lester Alan Pelton back in the 1870s as a more efficient version of a water wheel that allows you to squeeze everything out of a water stream in a closed environment. Only the Pelton water wheel can do up to 3000 rpm, which is 6 times faster than the rotor of a helicopter.
Pelton turbine rotor
Its principle of operation is that water is supplied from nozzles under high pressure. Its jet hits the spoon-shaped blades. This shape allows the maximum use of all the kinetic energy of the water jet instead of spraying it to the sides. From below, each blade has a drain for water that has already transferred kinetic energy. Thus, the Pelton turbine works best with small volumes of high pressure water, although its capabilities include operation even at pressures of 15 m.
The Pelton turbine has received relatively little changes over its 150 year history. For example, the material of the blades changed to tungsten carbide due to the fact that steel parts wear out quickly at such high pressure. Then they began to be replaced with composite or plastic ones with a shorter service life, but much less cost. The key change was the increase in the number of water nozzles. With only one nozzle, water can flow unevenly, which leads to uneven bearing wear and catastrophic consequences if the wheel is suddenly skewed and jammed. In addition, the use of 2-6 nozzles significantly increases the efficiency of the turbine.
Pelton turbine water jet
Prospects for the Pelton turbine in Ukraine
The western regions of Ukraine are the most promising. The mountainous terrain and the presence of a large number of mountain rivers and springs will make it possible to combine an efficient hydroelectric power plant with Pelton turbines. But the Carpathians are much lower than the Alps, limiting the use of such hydroelectric power plants. It is also important to remember about the need to build a dam that will harm the environment. Therefore, now in the near future there are prospects for the construction of only small and ultra-small hydroelectric power plants based on the Pelton turbine.
Theoretically, we can displace a maximum of 34% of polycrystalline panels. But it will be very difficult and expensive. And such a panel will never get its money back if we don’t launch it into space. And this slows down the development of alternative energy and limits what we can squeeze out of the sun without covering the entire regional solar panels.
But why make the whole solar cell super-technological, if you can just focus solar radiation on small photovoltaic cells? After all, a small high-efficiency photocell is hundreds of times cheaper than a large canvas. And it was the idea of using solar cells with small high-efficiency photovoltaic cells in combination with light traps and lenses that led to the appearance of Insolight solar panels and other MELA-based batteries (Multi-Element Lenset Array).
Why is this necessary?
Today, buying a polycrystalline solar panel with an efficiency factor of 20% is very, very good. And usually their efficiency ranges from 12-18%. And which one to choose already depends on your area and roof area. Therefore, owners of large plots can take the cheapest option and have their own solar power plant of alternative energy, which is limited in size and capacity only by law. That is, 50 kW is not a problem if there is a place to put it.
On the other hand, the classic 6 acres with a dacha is too small an area even for a 20 kW solar power plant, not to mention 30 kW and 50 kW. But it is quite another matter if you have solar panels with an efficiency of 2-4 times greater. Thus, the required area will be reduced many times.
How does it work?
In general, there are several concepts. The least practical for the average Ukrainian is a battery that resembles an ordinary satellite dish, but instead of a radio signal, the mirror focuses on the photocell reflected sunlight. Unfortunately, this option is too cumbersome for mass use and not very aesthetic.
are more progressive Insolight panels. They use highly efficient photovoltaic cells. They are arranged in a matrix. Instead of glass, such a panel has an array of lenses that focus light on photovoltaic cells. It is worth noting that the base with photocells and the array of lenses are movable and constantly shifted throughout the day. Thus, the focused beam always remains on the photovoltaic cell.
More sophisticated, but slightly better are the MELA solar panels offered here. Their feature is the use of two planes with lenses that form a “trap” for light and normalize the angle of incidence of sunlight. That is, solve the problem of a sharp drop in the efficiency of solar panels
in the morning and evening, when the angle of incidence is far from optimal. In tests, their panels really showed good results. And they also use ordinary amorphous solar panels.
Conclusions
Is it worth looking for such solar panels in the country? Not yet. This technology is still being tested and, unfortunately, has no examples of successful mass commercial use. Therefore, the only thing we can advise you is to keep your hand on the pulse and look towards the usual solar panels and make the most of the green tariff at current rates.
A car that requires no gasoline or outlet. Sounds like fiction, doesn’t it? In fact, it is fantastic and you will not be able to drive a jeep that has only a solar panel and an electric motor. Just the maximum power, for example, Tesla Model 3 reaches 615 kW, which allows this car to accelerate to 100 km / h in just 2.6 seconds. And this is a very good result even for a sports car.
An ordinary car has an engine with an average power of 100-150 horsepower or 75-107.5 kW. But the solar panel with an area of 2 square meters, just about the area of the roof, in broad daylight will give only 400 watts of power. That is a little more than half the horsepower and to accelerate a car weighing several tons by the sun alone will not work. Thrust will be about as much as one weightlifter instead of 100 horses.
Do solar cars have a chance?
Installing solar panels on cars themselves is not a good idea. The angle of such a panel will always be not optimal, and the buildings and trees standing on both sides of the roads will cut off even more of those crumbs of energy. But there is a solution that will definitely work. For example, the same company Tesla offers to use electric trucks. Thus, freight will be much cheaper, because solar power plants can be located at bus stations. And arriving at the bus station, the truck will not only leave the cargo and receive a new one, but also recharge or replace its battery with a fresh and fully charged one.
Can I DIY a solar electric car myself?
In short, yes! Of course it will not be a car in the usual sense for us. But to make a small electric car that does not need a gas station or socket – is quite real. And this was proved by his “Do It Yourself” video YouTuber Mark Gavier.
All he did was install four 1,000-watt bicycle motors on a sturdy metal frame and make a roof out of 200-watt solar panels. To store electricity, he used conventional 48-volt batteries for electric bikes with a capacity of 10 ampere hours. According to him, his light electric car can travel up to 20 km on one battery, and this battery is charged for about 2-3 hours on a sunny day.
Of course, this is not the optimal transport for the city. But the use of such transport on large enterprises, farms and villages could save a lot of time. Or, for example, such a car can be used as a golf card. The advantage of such transport is the absence of the need to refuel it, the absence of engine noise and relative reliability.
The price of the project was 2000 euros. But if you use cheaper components, you can reduce the cost of the electric car at least 2 times. In addition, it should be borne in mind that this is a prototype.
Solar yachts
On the other hand, electric yachts, which can also run on solar panels, have long been a reality. Even a small yacht has enough deck and roof area for superstructures to accommodate a solar power plant up to 10 kW. And this is a good power. Of course, you should not count on jumping on the waves like on a boat, but to accelerate to 7-10 km / h is quite real. And this is a good result for a regular yacht.
Currently, the best option is to use solar panels and batteries to power the shunting engine of the yacht with a mast. That is, when leaving the harbor, passing under bridges and in calm, you can use an electric motor, and the rest of the time – the force of the wind. Meanwhile, the solar power plant will provide the necessary energy for lighting, cooking, powering navigation, control and communication devices.
Another example is the use of a combined system from a powerful solar power plant, a high-capacity battery, and a backup diesel generator. Typically, such a yacht can move at a speed of 12-14 km / h for more than 4 hours on a single battery. In sunny weather, whose time increases significantly. And if you add stops for rest and diving, the solar energy is enough for a small tour.
Reducing the scale, it is quite effective to use solar panels for traction on small fishing boats only a few meters long. In this way you can get a pretty decent quiet river transport, although not too fast.
On the other hand, scaling up and building solar-powered tankers and container vessels is an unrealistic task. The problem is that the heavier the ship, the more water it displaces and the more water it resists. Thus, the MV TransAtlantic 100 meters long, capable of transporting 5,000 tons of cargo, has a power plant with a capacity of 3.6 MW or almost 5 thousand horsepower. If even the entire deck area is covered with solar panels, the resulting power will be only 10% of the required.
Conclusions
Transport is purely solar-powered – it is actually unrealistic. And all because of the fact that the maximum flux of solar radiation at sea level reaches 1020 W / m2. And even panels with 100% efficiency would allow to receive power in 3-4 horsepowers for the car. But even the 1908 Ford Model T had a 20-horsepower engine. It is a radically different matter if you use stationary solar power plants to recharge your car. And this, by the way, will not just be, but is already a much cheaper alternative to gasoline.
Many manufacturers and companies that install small solar power plants on private farms say the following “Set and forget.” But is it really possible to install a solar panel and forget about its existence? Just get electricity or even earn without the need to maintain it regularly.
Dust storms, unfortunately, are now a harsh reality.
Dust, sand and dirt are the enemies of every solar power plant owner. After all, they cut a lot of the efficiency of the panel and can deprive you of a third of the nominal power. Or a third of income. In addition, the dust storm used to be a miracle for Ukraine. Similarly, for example, snowdrifts have always been the norm in Kyiv. But the winter of 2020 was full only of rains and snow very seldom fell from the sky.
The utilities were happy about this, but the other side of the coin did not delay and in the spring, in addition to the pandemic, Kyiv residents faced air full of smoke, ash and dust. Of course, this is primarily a health threat. But it is also a loss of clear sunny days due to reduced air transparency, and a large amount of dust and ash that settles on various surfaces. Including and solar panels.
Temperature change
Rising temperatures in winter indicate nothing more than climate change. In Ukraine, it is getting warmer every year, although the angle of inclination to the sun remains unchanged. But this creates some problems for owners of solar panels, because their efficiency decreases with heating of photovoltaic cells. When the wind is cool, the solar panels give off enough heat without additional cooling systems. But the rise in average annual temperature three times faster than in the rest of the world is an alarming signal.
Spark – automatic solar panel cleaning system
An effective solution is the Spark system, which to understand its principle of operation can be called “automatic solar panel watering system”. Its feature is that it works for 15-20 seconds, spending the minimum amount of water as efficiently as possible. That is, with minimal consumption, it effectively cleans the surface of the solar panel from ash and dust. And also cools it that maintains temperature of photocells at the necessary level for the most productive work. In order to prevent excessive water consumption, we recommend installing a drainage system and using the water left over from washing the solar panels for irrigation.
The area of solar panels is an excellent collection of water for irrigation.
It is worth noting that cleaning solar panels by hand is very expensive, because cleaning with a garden hose is not so economical in terms of water consumption. And it’s also an obvious waste of time. It is worth mentioning that dry cleaning with a broom is not a good idea, because micro-scratches reduce the efficiency of solar panels much more than dust.
Another important advantage of Spark is compatibility with any solar panel, regardless of the form factor and size. So this system is definitely suitable for your private solar power plant. And the sprinklers themselves do not form shadows on solar panels. And Spark is fully controlled from a smartphone. So you can set the necessary cycle at any time or turn off the system.
This material is allowed to be used for educational purposes.
What is an energy cooperative?
The definition of an energy cooperative is very simple. This is a cooperative that allows citizens to provide their needs (both individual and general) related to energy consumption.
Energy cooperatives can perform the following tasks:
General procurement of energy raw materials (purchase of firewood, pellets; production of briquettes / pellets from straw and wood, growing energy vines).
Wholesale purchase of services related to energy efficiency (energy audit services, thermal modernization of residential and industrial or office facilities).
Financing the acquisition by members of a cooperative of power plants (boilers, batteries, solar panels, etc.).
The production of electricity from alternative energy sources (in particular, the installation of solar and wind power plants, bio-thermal power plants on straw and wood chips).
Heat production (both for members of a cooperative and for heating entire streets or areas in villages and cities): in a village, plants for the extraction of biogas from animal waste, in the city – solid fuel boilers.
Autonomous heating and hot water supply from solar collectors.
Cooling and centralized air conditioning (for example, as in Barcelona).
It is worth noting that these are just the simplest examples of models of energy cooperatives. In fact, there are many more. For example, in Germany there is a Friends of Prokon cooperative that manages development projects in the field of renewable energy sources. In the USA, hundreds of cooperatives provide electricity to rural areas and have significant distribution networks and generating capacities. However, let us return to our local capabilities.
A simple example in our conditions, an energy cooperative consists of several owners who have come together to buy a wood chip crusher together. This simple device costs about $1000, but not every owner can afford it, and an individual owner will have to stand an idle crusher 90% of time.
However, the combination of financial efforts of a small microcommunity provides tangible benefits to all its members. Chips beautifully lit in the boilers, and each of the members of the cooperative may use a wood crusher to provide themselves with chips for the heating season. In addition, a wood crusher allows to turn into the fuel almost any remnants of the tree that would previously become garbage. With the ever-increasing price of gas and other energy carriers, such a joint investment by members of the cooperative in a wood crusher is more than justified and pays off in just one season.
Such a model is only the beginning. Energy cooperatives can produce briquettes / pellets, grow energy willow, build biogas and solar power plants. Our legislation has a number of problems that create restrictions on the development of energy cooperatives, but today the opportunities for using the cooperative model in the energy sector are impressive.
Why do we need energy cooperatives?
Friedrich Wilhelm Raffeisen, is one of the founders of the cooperative movement in Germany. He argued that the cooperative allows you to consolidate resources and direct them to solving common energy problems. They allow you to solve problems that are beyond the power of one person, because he has few resources. However, bring together the resources of at least 10 such people – and you will see that together they can solve problems that are significantly larger in scale than before.
Energy cooperatives can provide a large number of their own needs related to energy without interacting with the state, without waiting for the next government decree or the goodwill of the monopolists. Trust and joint action allow you to provide yourself with fuel, receive wholesale discounts on insulation or power equipment, and establish joint production of energy or energy resources (for example, pellets or briquettes).
In general, the work model of energy cooperatives is limited only by the imagination of those who create them and by law. Despite the problems with the latter, their creation already has the potential to remove hundreds of thousands of communities from the state of energy poverty and provide reliable supply of local energy resources.
World practices of energy cooperatives
An energy cooperative is an important participant in the energy markets of developed countries. One of the first examples is Germany. In a country that is rapidly moving from fossil and nuclear energy to the increasing use of renewable energy sources, more than 700 active energy cooperatives operate here. They are created for a wide variety of purposes. Probably the most among them are those who combine the financial resources of citizens in order to seize the opportunity to earn money on a “green tariff”. This created a situation in which in 2012 private households and energy cooperatives owned 47% of the installed renewable energy capacities in Germany.
Energy cooperatives became one of the driving forces of the German energy revolution (Energiewende) and allowed attracting billions of euros from ordinary German citizens to the green economy even when the German energy giants were very ambivalent about the prospects of abandoning fossil fuels.
Energy cooperatives in Germany are working on very different models. In addition to selling energy by ‘green tariff” from solar, there are hundreds of energy cooperatives that provide local residents with heat, electricity, and network services. Many of them were created by residents of one street in order to arrange centralized heating on it using local raw materials. However, there are quite large cooperatives that operate with significant electricity generation capacities.
Energy cooperatives have also gained considerable popularity in Denmark, the Netherlands, Sweden, Australia, and Great Britain. And the movement of energy cooperatives gained special power in the United States. According to the Touchstone Energy Cooperatives Association, which has 750 members, energy cooperatives are located in 46 states. Together they form the largest energy network in the United States, providing energy to millions of Americans who are their co-owners. Most of them have no idea that somewhere in our country the only option to get electricity is to join the regional power network. The history of some energy cooperatives stretches from the 40s, 30s, or even 20s of the XX century.
What opportunities do energy cooperatives offer for us?
Energy cooperatives certainly cannot solve all the problems of the energy sector in our country. However, they can be an important decision for a huge number of people and communities, large and small communities, which can, without hope for the state, provide themselves and other energy resources and create a new quality of life.
Energy cooperatives are a good mechanism for transforming trust in each other into an effective mechanism for the transition from a too centralized post-Soviet model of energy to a more localized one, which is assigned primarily to local resources and creates jobs, new economic models and opportunities for residents of the communities.
Energy cooperatives in Ukraine
In Ukraine, the first simplest energy cooperatives are just beginning to be created. The simplest and most promising model of an energy cooperative in the conditions of a Ukrainian village is the joint procurement by several farms of raw materials for the production of straw fuel briquettes / pellets. Indeed, it is expensive to buy such an installation for one owner, and he may not have enough raw materials to load equipment. In the western regions, owners are joining together to buy wood shredders.
For example, several farms specializing in raspberry cultivation created the Yagіdniy Krai cooperative in the village of Losyatin, Ternopil Region, and bought refrigerators for storing berries together. For their own energy supply, they bought a plant for the manufacture of fuel briquettes from raspberry stalks, and they use it together.
Energy communes: energetical independenca for communes
Near Kharkov, 12 farms united into a cooperative for the production of biofuel from rapeseed, which they themselves grow. The necessary equipment was purchased for a grant.
One farmer could not get much funding from the grant program, and the energy cooperative, combining assets, could. The farmers use the biodiesel produced to fuel their own agricultural machinery (which allowed them to reduce production costs), as well as for a school bus and ambulance.
Another example is from the Kharkov region: three private households created an energy cooperative and got a cheap loan together to build a mini solar power plant on the roofs. They not only provide for themselves, but, having created a legal entity, sell 2/3 of the generated electricity, earning about 10 thousand UAH per month. The project will pay off in 2.8 years.
Today in Ukraine, about 1000 solar power plants have been built on the roofs of private households. The first solar power plant also appears on the roofs of high-rise buildings (which is prevented by legal issues).
The economy of such a solar energy cooperative is calculated separately for each energy cooperative. Before building a solar power station, it is necessary to find out in Ukrenergo whether they have free capacity for connection.
In Ukraine, it is profitable to sell coolants and it makes sense to build boiler houses on biomass (straw, grain, corn, sunflower and other crops).
In rural areas, it is beneficial to build bio-TPPs – cogeneration plants for the production of heat and electricity at the same time on biomass, which will provide them with complete energy independence. According to experts, such projects will pay off in two heating seasons.
However, the rapid development of energy cooperatives in Ukraine is hindered by the fact that complex models of cooperatives for the production of heat and electric energy still require permits and licenses. That is why activists have prepared and are now demanding the adoption of a law “On Good Energy Cooperatives,” which will simplify their activities.
To implement local projects in the field of alternative energy, residents, organizations and enterprises are united in the so-called energy cooperatives. Often, energy cooperatives strive for independent, independent of anyone environmental production of electricity. In other words, this is a peculiar form of civic activity or public participation in processes related to politics, adoption of laws and local decisions – at the level of regions and communal societies.
Residents of the EU are well aware of all the advantages of switching to environmental renewable energy sources. In Europe, they are not only actively implementing the use of alternative types of energy, but are also constantly increasing their pace by organizing activities in the form of cooperatives. As an example, it is worth looking at the UK, which has about 5,000 energy cooperatives using solar and wind energy.
Energy holdings in Germany nowadays feel serious competition from energy cooperatives, as the latter produce about 30% of their electric energy through the use of wind farms. In this regard, the Clean Energy for All Europeans energy package in the EU countries restricts the right to connect energy cooperatives primarily to the network.
Also, energy cooperatives are first obliged to provide their own needs for the carriers of electricity that they generate, and to sell the remainder in the network according to the “green tariff”.
In the next ten years, the EU sees a temporary energy perspective in the use of energy cooperatives. According to studies conducted by CE Delft: as early as 2030, house managements and cooperatives that are participants in the energy market will occupy about half the population of the European Union. And cooperatives producing electricity will contribute 20% (today – 9.8%).
In rural areas, especially in isolated villages, where the problem of stable electricity supply is quite large, energy cooperatives using the energy of direct and diffuse solar radiation (sunlight) have an excellent chance to become profitable for village communities.
In this regard, the production of electricity generation facilities in rural collective enterprises or the union of producers of agricultural products of different volumes into energy cooperatives may serve as an impetus for future energy independence.
In this case, an excellent solution would be to create special loan packages from banking organizations (typical for such projects) for energy cooperatives in agriculture. The calculations mentioned above were carried out taking into account Ukrainian credit rates. When attracting more financially profitable European money, projects for the generation of heat carriers and cogeneration of electricity should pay off within 3-4 years.
The climate and the “green” tariff in Ukraine significantly accelerates the payback process and increases the income of cooperative participants.
When creating a business plan for a future energy cooperative to provide members with heat, it should be noted that in Ukraine such activities today require the receipt of the following permits, namely:
obtaining licenses: for the production of thermal energy; transportation of thermal energy; heat supply. Relevant licenses are issued by regional state administrations;
compliance with licensing conditions for the number and qualifications of personnel, technological conformity of processes, organization of accounting and reporting;
approval of fixed tariffs in local authorities;
confirmation of the intended use of land on which boiler and heating networks are located, etc.
This material is allowed to use for educational purposes.
The concept of a green tariff is enshrined in the law on electricity: it is a tariff at which the wholesale Ukrainian energy market must buy electricity produced at electricity facilities from renewable energy sources (including solar and hydropower). Electricity suppliers must purchase it in cases, volumes and at prices determined by the National Electricity Regulatory Commission of Ukraine (NERC). That is, the green tariff in Ukraine is a mechanism to encourage citizens to produce electricity from renewable energy sources.
Consider briefly how you can make money on private power plants. The legislation of Ukraine prescribes 2 options for the installation of electric photovoltaic cells: on the territory of a private household (up to 30 kW) and in the form of business projects (up to thousands of kilowatts). Investments in such projects differ significantly, and the necessary documentation is also different. It is clear that the time for projects will also not be the same.
Rates for “green kilowatt”
Rate of “green” tariffs in 2016-2019 according to the resolution of the NERCEC of June 30, 2016 № 1188.
Private sector
For solar panels
The following cost of one kilowatt of solar energy (according to the resolution of the NERCEC under the number of one thousand one hundred and eighty eight, which came into force on August 16, 2016):
from January 1, 2016 to December 31, 2016 – 534.43 kopecks / kWh (excluding VAT);
from January 1, 2017 to December 31, 2019 – 508.69 kopecks / kWh (excluding VAT);
from January 1, 2020 to December 31, 2024 – 457.22 kopecks / kWh (excluding VAT);
from January 1, 2025 to December 31, 2029 – 407.26 kopecks / kWh (excluding VAT).
For wind generators
from July 1, 2015 to December 31, 2019 – 327.02 kopecks / kWh (excluding VAT);
from January 1, 2020 to December 31, 2024 – 293.71 kopecks / kWh (excluding VAT);
from January 1, 2025 to December 31, 2029 – 261.92 kopecks / kWh (excluding VAT).
For legal entities and businesses
As for generation on an industrial scale, it takes into account the year of construction and placement of alternative energy sources.
In addition, the mandatory condition for industrialists concerning domestic equipment has been abolished. Today, business owners have the right to use devices from any foreign brand.
At the same time, the installation of domestic batteries or wind generators is now stimulated at the state level by increasing tariffs by 5-10%.
To get a higher rate, you need to use in installations up to 30-50% of domestic nodes. That is, to use Ukrainian solar panels or wind generators is economically profitable.
Tariffing for solar panels on the ground:
2016 – 0.16 euros;
2017-2019 – 0.15 euros.
Tariffing for solar panels on the roof:
2016 – 0.172 euros;
from 2017 to 2019 – 0.163 euros.
Important points of the green tariff
In the calculation of the cost of a kilowatt of energy produced on an industrial scale, special coefficients are used.
The existing retail price is multiplied by a certain factor – as a result, the cost of a kilowatt is determined by the “green” tariff.
Dynamics of increasing the number of small private solar power plants.Orange – number. Green – power.The overall investiment is 180 milion EUR.
Changes in the coefficient depending on the energy source:
alternative energy facilities of the terrestrial type – 4.8;
installations mounted on roofs with a capacity of 100 kilowatts – 4.6;
installations mounted on the roofs and facades of buildings with a capacity of less than 100 kilowatts – 4.4.
Meters made by Ukrainian manufacturers are used to measure electricity. Models of reversible type on one or three phases are established.
It should be noted that the rate is fixed once – at the time of concluding a contract with a local state-owned energy company. Further reduction of owners’ tariffs will not apply.
Power requirements for equipment producing electricity Power
restrictions apply only to private homes and households. Until recently, the permissible maximum was 10 kilowatts.
From 2016, private property owners can safely buy more powerful solar panels – the upper limit for these devices is 30 kilowatts per hour. The same applies to wind turbines.
For obvious economic reasons, there are no restrictions for businesses. For them, the possibilities of their own budget will be crucial, from which investments will be made in the system of alternative energy supply.
Procedure for obtaining a green tariff for private individuals
Any civilian has the right to install generating capacity for electricity generation in private ownership. In this case, the amount of electricity produced should not exceed the norm established by the contract on the use of electricity. A citizen has the right to sell electricity to energy suppliers at a green tariff in excess of the monthly norm of personal consumption. You don’t need any licenses, you don’t need to follow the additional “instructions” of local officials – you just put your own electricity generating capacity and start earning a green tariff. Payments for electricity and the procedure for issuing a green tariff, as well as the procedure for energy accounting and its sale are approved by NERC.
To issue a green tariff in Ukraine in 2018, it is necessary to perform a number of actions:
Purchase and install an electrical installation (wind turbine, photocells or others) with a capacity of not more than 30 kW.
Submit an application and connection scheme to the local office of the electricity supplier (oblenergo, rayenergo).
To receive funds for electricity sold, an individual must open a bank account, the details of which are specified in the application.
Agree on the wiring diagram of the power plant.
Arrange a metering unit for privately owned electricity.
Sign an additional agreement with the energy company for the purchase and sale of electricity generated by renewable energy sources.
More about the procedure for obtaining a green tariff for individuals.
Equipment for electricity generation using solar, wind and water energy is quite expensive and technologically complex, its selection and installation should be done by professionals. For example, to install photovoltaic cells to convert solar energy into electricity, you need to buy the solar panels themselves, mains inverter, protection equipment, metal structures, consumables (cables, mounts, connectors).
The benefit of connecting to the green tariff
Every year, the number of households that earn with the help of renewable electricity installations is growing. Some citizens install solar photovoltaic cells, which is especially convenient in the southern and eastern regions of Ukraine, where there are more sunny days. And where there are many windy days, it is more profitable to use wind turbines.
For residents of hilly and mountainous areas, where there are fast streams and small rivers, there is an option to build a mini-hydroelectric power plant. That is, each option can be implemented in certain natural areas. Of course, the cost of its own power plant, although small, is quite high: on average, a plant for generating 3-5 kW of electricity can cost 4-6 thousand conventional units, and larger units will cost up to 25-28 thousand USD.
Payback of solar power plants – about 5-6 years. This is not a small amount, but considering that you provide yourself with energy, do not depend on economic crises and fan outages, the advantages are obvious. Selling electricity at a green rate, you can earn up to five thousand USD. per year, depending on the capacity of your private power plant.
Currently, more and more citizens are interested in the green tariff in Ukraine. A number of the most enterprising people are already selling electricity generated in their own backyard, already in our region, and thousands of such installations throughout the country. This is a profitable investment and a stable way to earn money for everyone. And with our ready offers on a basic complete set of solar stations and the help in registration of the green tariff also it is easy!
Green tariff for legal entitiesgreen tariff for legal entities is
Theno less interesting. Organizing your own mini-power plants for a few hundred kilowatts is a great investment in our difficult times. A businessman can organize the production of electricity to ensure its production capacity and not depend on the central supplier, and sell the surplus at attractive prices at a green rate. Such investments pay off in 5-7 years. That is, the income will be about 400%, based on the average service life of solar panels of 25 years and current electricity prices.
In order for a legal entity to start working at a green rate, it is necessary to have a number of documents. The first thing to do is to get a feasibility study for a green tariff power plant. It can be used to assess the risks and benefits. This document contains basic information on the implementation of the business plan. In addition to the justification, you need to have information about the capacity of the power grid through which you plan to sell electricity.
The terrain, thetaken into account slope of the site to the sun, winds during the year, clouds and other natural features are. When planning to build a power plant, think seriously about registering a new legal entity – it will save you from a number of difficulties in the future. Finally, the equipment you buymust be certified and meet the requirements of Ukrainian standardization bodies.
The most popular questions about the “green” tariff
How to increase the profitability of a home solar power plant?
Some people think that investing in domestic solar energy is unprofitable due to the high cost of equipment and the relative cheapness of grid electricity. But this is not the case. To increase the profitability of the installation allows feed-in tariff, or “green” tariff: according to the owners of stations, the proceeds from the sale of surplus electricity offsets the cost of purchasing and installing SES for 5-8 years.
Who can use the feed-in tariff?
Only owners of private houses who have installed photo panels with a capacity of up to 30 kW on a private plot, facade or roof of a building can sell solar electricity to energy suppliers. The feed-in tariff program does not apply to photovoltaic high-rise systems. It cannot be used by owners of autonomous power plants, as such installations are not designed to connect to the general network.
Is it possible to get a soft loan for the construction of solar power plant under the “green” tariff?
Loans for the purchase and installation of solar panels at 0.01% per annum are issued by Ukrgasbank under the ECO-Energy program. The loan amount is UAH 1,000-1,000,001. Terms – 1-5 years. Under the terms of the bank, the own contribution should not be less than 15%. However, experts recommend taking a loan if the purchase is not enough 30-40%. In this case, the income from the “green” tariff fully covers the payments to the creditor. It is planned that from 2018 the situation with soft loans in Ukraine will become even better in connection with the launch of the Energy Efficiency Fund.
How long does it take to connect to the “green” tariff?
According to the law, after submitting the required package of documents, a three-week period is allotted for consideration of the issue. On the fact of registration by own forces lasts a month and a half. Companies that sell and install photovoltaic equipment often help speed up the connection process.
Why do feed-in tariff payments depend?
Rates are pegged to the euro, but the money to the current account of the station owner comes in national currency. The tariff grid in hryvnias is set quarterly by NKREKU. The amount of payments is also affected by the year of commissioning of the solar power plant, the presence / absence and the amount of the local component in the photovoltaic system (for the use of domestic equipment is a surcharge of 5-10%).
Do payout rates decrease over time?
According to European experts, the “green” tariff in Ukraine is one of the highest in the world. However, as everywhere, it is only an incentive tool, ie as the number of solar power plant increases, the amount of payments will decrease. The amount of charges directly depends on the year of commissioning of the facility, so the earlier the solar power plant is built, the more profitable it is.
Is it possible that the program will be frozen?
Feed-in tariff, as an incentive mechanism for the transition to alternative energy sources, has been widely used around the world for several decades. In Ukraine, such a program is enshrined in law, guaranteed by the state and is valid until 2030. In some regions, of course, there are delays in payments, but there is no question of waiving the tariff.
Making a forecast regarding the volumes of generated electricity of solar power plant
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The objectives of the feasibility studies for the design of electricity supply are:
1. Justification of investments (long-term capital investments) in new or reconstructed solar power plant and subsequent operating costs by comparing options according to accepted efficiency criteria.
2. Proof of the technical functional capabilities of the solar power plant that meet the reasonable requirements of consumers of electricity (the necessary bandwidth of the elements, ensuring the reliability of power supply, quality of electricity, etc.). At the same time, the selection and justification of electrical equipment is carried out to perform the necessary functions and requirements, as well as an assessment of the state of the solar power plant in normal and post-accident conditions.
3. Evaluation of quality indicators and national economic significance of the decision. The selection of a technically-economically feasible electricity supply scheme of an enterprise is based on the consideration and comparison of several possible options for technical, operational and economic indicators.
The solar power plant technical indicators include the number and levels of voltage levels, voltage deviation and loss, the failure-free operation and the stability of solar power plant elements in transient conditions, the stability of electric drives, the degree of automation, etc. Operational indicators include the duration of power supply recovery after the localization or elimination of damage, the duration repair and overhaul, permissible overload of solar power plant elements, power and electricity losses, ease of operation, The number and qualifications of staff. The most important economic indicators when comparing solar power plantoptions are given annual costs and the payback period of investments. For a more detailed economic assessment of options, additional indicators are used: capital investment in the solar power plant, the cost of power and electricity losses, damage from sudden power outages, etc.
When performing technical and economic calculations, objective difficulties arise due to the fact that the enumeration of all possible options is associated with significant labor costs for designers even with automated data processing. In addition, many of the compared indicators are difficult to quantify (for example, ease of use, flexibility, reliability, etc.). In this regard, the correct selection for comparing several options depends on the erudition, experience and qualifications of the designers.
CHOICE OF ECONOMICALLY IMPLEMENTABLE AREA OF THE CONDUCTOR SECTION
The conductor cross-sectional area is an important parameter of overhead and cable lines. With an increase in the cross-sectional area of the conductors, the costs of building power lines increase, but at the same time, the loss of electricity decreases. Reducing the cross-sectional area to the technically permissible limit reduces investment, but causes an increase in line losses. In this regard, the correct choice of the cross-sectional area of the conductors, taking into account specific conditions, is an important and responsible task in the design of solar power plant.
When designing power lines with voltage up to 220 kV, the choice of the cross-sectional area of the conductors is carried out not by a comparative technical and economic calculation in each case, but by normalized generalized indicators. The values of economic current density for overhead and cable lines are used as such indicators. The economic current density establishes the optimal ratio between deductions from capital investments and the cost of electricity losses in the line. An economically feasible cross-sectional area of the conductors F is selected from the relation f, = x, where / is the rated line current in normal mode, A; j is the normalized value of the economic current density, A / mm2.
In the process of transmission, distribution and consumption of electric energy, the total losses in generators, transformers, power lines of various voltages, electric motors, converters and technological installations reach 25-30% of all electricity generated at power plants. Of these, a significant proportion, up to about 10-15%, are accounted for by power supply systems. In this regard, the determination of power and electricity losses is an important issue in the design of solar power plant for industrial enterprises, which is essential for the feasibility study of circuit options, the selection of rational nominal voltages, compensating and regulating devices, etc.
Losses of active power and electric power in the elements of the solar power plant are made up of no-load losses and load losses. Idling losses do not depend on the load of the solar power plant elements and arise due to magnetization reversal of the cores (losses due to hysteresis and eddy currents), ionization of air near overhead lines wires 220 kV and higher (losses per crown), leakage currents due to imperfection of insulation, etc. .d. These losses for various elements are indicated in the form of absolute or specific values in the passport data or in reference books. Load losses are heat losses that change in direct proportion to the square of the current flowing through the active resistance of the solar power plant element.
Losses of active power in the power line (LRL), which are used to heat the conductors, are calculated by the expression ARl = 3 • P-R, (3.4) where / is the line current; R is the active resistance of the wire or core of the cable, defined as R = r 0 l, (3.5) where t “0 is the specific (linear) resistance of the conductor, Ohm / km; / is the line length, km.
Calculation of solar power
To calculate necessary power solar panels need to know how much energy you consume. for example, if your energy consumption is 100 kWh per month (readings can be viewed on the electricity meter), respectively, then you need to solar panels generate this amount of energy.
Sami solar batteries They produce solar energy only during daylight hours and give out their nameplate power only if there is a clear sky and direct sunlight falls at a right angle. In cloudy weather, the power of solar panels drops by 15-20 times, even with light clouds and haze, the power of solar panels drops by 2-3 times, and all this must be taken into account.
When calculating, it is better to take working hours at which the solar panels operate at almost all capacity for 7 hours, from 9 a.m. to 4 p.m. The panels, of course, in the summer will work from dawn to dusk, but in the morning and in the evening the output will be very small, in volume only 20-30% of the total daily output, and 70% of the energy will be generated in the interval from 9 to 16 hours.
Thus, an array of panels with a capacity of 1 kW (1000 watts) for a summer sunny day will produce 7 kW * h of electricity for a period from 9 to 16 hours, and 210 kW * h per month. Plus another 3 kW (30%) in the morning and evening, but let it be a reserve, since variable cloud cover is possible. And our panels are installed permanently, and the angle of incidence of the sun’s rays changes, this naturally the panels will not give out their power at 100%. It is clear that if the panel array is at 2 kW, then the energy production will be 420 kWh per month. And if there is one socket per 100 watts, then per day it will give only 700 watts * h of energy, and per month 21 kW.
It’s nice to have 210 kWh per month with an array of only 1 kW, but it’s not so simple:
Firstly, it’s not that all 30 days are sunny, so you need to look at the weather archive in the region and find out how much overcast days by months. As a result, it will probably be cloudy for 5-6 days, when the solar panels and half of the electricity will not produce. So you can safely cross out 4 days, and it will turn out not 210 kW * h, but 186 kW * h.
You also need to understand that in spring and autumn the daylight hours are shorter and there are significantly more cloudy days, so if you want to use solar energy from March to October, you need to increase the array of solar panels by 30-50% depending on the specific region. But this is not all, there are also serious losses in the batteries, and in the converter (inverter), which also must be taken into account, more on that later.
We won’t talk about winter yet, since this time is very deplorable in terms of generating electricity, and when there is no sun for weeks, no array of solar panels will help, and you will either need to be powered from the network during such periods, or put on a gas generator. The installation of a wind generator also helps, in winter it becomes the main source of electricity generation, but if of course there are windy winters in your region, and a wind generator of sufficient power.
Calculation of the battery capacity for solar panels
The smallest reserve of battery capacity, which is simply necessary, must be such as to survive the dark time of the day. For example, if you have 3 kWh of energy consumed from evening to morning, then the batteries should have such a supply of energy.
If the battery is 12 volts 200 Ah, then the energy in it will fit 12 * 200 = 2400 watts (2.4 kW). But batteries cannot be discharged 100%. Specialized batteries can be discharged to a maximum of 70%, if more, then they quickly degrade. If you install ordinary car batteries, they can be discharged by a maximum of 50%. Therefore, you need to put the batteries in twice as much as required, otherwise they will have to be replaced every year or even earlier.
The optimal reserve capacity of a battery is the daily supply of energy in batteries. For example, if you have a daily consumption of 10 kW * h, then the working capacity of the battery should be just that. Then you can easily survive 1-2 cloudy days without interruptions. Moreover, on ordinary days during the day the batteries will be discharged by only 20-30%, and this will extend their short life.
Another important thing to do is the efficiency of lead-acid batteries, which is approximately 80%. That is, a battery with a full charge takes 20% more energy than it can then give. Efficiency depends on the charge and discharge current, and the higher the charge and discharge currents, the lower the efficiency. For example, if you have a 200Ah battery and you connect a 2 kW electric kettle through the inverter, then the voltage on the battery will drop sharply, since the discharge current of the battery will be about 250 Amps, and the energy efficiency will drop to 40-50%. Also, if you charge the battery with high current, then the efficiency will decrease sharply.
The inverter (energy converter 12/24/48 to 220v) has an efficiency of 70-80%. Given the loss of energy received from solar panels in batteries, and the conversion of direct voltage to AC 220V, the total loss will be about 40%. This means that the battery capacity reserve must be increased by 40% and the array of solar panels must be further increased by 40% to compensate for these losses.
But this is not all the losses. There are two types of solar battery charge controllers, and you can not do without them. PWM (PWM) controllers are simpler and cheaper, they can not transform energy, and therefore solar panels can not give the battery all its power, maximum 80% of the rated power. But MPPT controllers track the point of maximum power and convert energy, reducing voltage and increasing charging current, and ultimately increase the efficiency of solar panels to 99%. Therefore, if you install a cheaper PWM controller, then increase the array of solar panels by another 20%.
Calculation of solar panels for a private house or cottage
If you do not know your consumption and just plan, say, to power the cottage from solar panels, then consumption is considered quite simple. For example, a refrigerator will work in your country house, which according to your passport consumes 370 kWh per year, which means that it will consume only 30.8 kWh of energy per month, and 1.02 kWh per day.
Shine. For example, your bulbs are energy-saving, say, 12 watts each, there are 5 of them, and they shine on average 5 hours a day. This means that per day your light will consume 12 * 5 * 5 = 300 watts * h of energy, and in a month it will “burn” 9 kW * h. You can also calculate the consumption of a pump, a TV, and everything else that you have, add everything up and get your daily energy consumption, and multiply it by a month and get some approximate figure.
For example, you get 70 kWh of energy per month, add 40% of the energy that will be lost in the battery, inverter, etc. So, we need solar panels to produce about 100 kWh. This means 100: 30: 7 = 0.476kW. It turns out that you need an array of batteries with a capacity of 0.5 kW. But such an array of batteries will be enough only in the summer, even in spring and autumn with cloudy days there will be power outages, so you need to double the array of batteries.
As a result of the foregoing, in a nutshell, the calculation of the number of solar panels looks like this:
accept that solar panels last only 7 hours in summer with almost maximum power,
your electricity consumption per day
divideby 7 and get the required power of the solar array,
add 40% to losses in the battery and inverter
add another 20% if you have a PWM controller, if you do not need MPPT
Example: Consumption of a private house 300 kWh per month, divided by 30 days = 7 kW, divided by 10 kW for 7 hours, it turns out 1.42 kW. Add to this figure 40% of losses on the battery and in the inverter, 1.42 + 0.568 = 1988 watts. As a result, an array of 2 kW is needed to power a private house in the summer. But in order to get enough energy even in spring and autumn, it is better to increase the array by 50%, that is, plus 1 kW more. And in winter, during long cloudy periods, use either a gas generator or install a wind generator with a capacity of at least 2 kW. More specifically, you can calculate based on data from the weather archive for the region.
Fundamentals of software and topology solar power plants.
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Performance Modeling
Sophisticated simulation software is used to predict the output of a solar power plant. Forecasting reports should take into account factors that negatively affect plant performance.
Calculation of energy production. Software Review.
To simulate a solar power plant, engineers should use only licensed software, which makes it possible to work with the most relevant databases on climatic conditions and equipment parameters. Using licensed software ensures that the results obtained will accurately predict the results of both industrial solar power plants and home use.
Uncertainty in predicting energy production for modeling the generated energy depends at each stage of modeling on the uncertainty of the input parameters. Software modeling in itself may allow uncertainties of 2% to 3%.
The use of solar cells coincides with the use of other sources of electricity, but unlike them, solar panels depend on the amount of light that falls on their surface. For example, in cloudy weather, clouds can significantly reduce the output power of the photovoltaic panel, up to 50%. Also, even a small defect in solar cells can reduce the efficiency even for panels from the same batch. Therefore, to ensure the desired power, it is necessary to sort the elements by the output current. An example is the following: if you try to insert a pipe with a smaller diameter into a water pipe with a rather large diameter, it is natural that the watercourse becomes smaller. The same thing happens in chains of solar cells if their parameters are heterogeneous.
Silicon solar cells cannot be described by Ohm’s simple law, since it is a nonlinear cell. Instead, to explain the characteristics of an element, you can use several simple curves – current-voltage characteristics (CVC).
The open circuit voltage generated by one element changes slightly when switching from one element to another in one batch and from one manufacturer to another and is about 0.6 V. This value does not depend on the size of the element. The situation is different with current. It depends on the light intensity and the size of the element, which means its surface area. An element with a size of 100 * 100 mm is 100 times larger than an element with a size of 10 * 10 mm and, therefore, it will give a current 100 times larger at the same illumination.
Peak power corresponds to a voltage of about 0.47 V. Thus, in order to correctly assess the quality of the solar cell, and also for comparing the cells with each other under the same conditions, it is necessary to load it so that the output voltage is 0.47 V. After the solar Elements are selected for work, it is necessary to solder them. Serial elements are equipped with current collecting grids, which are designed to solder conductors to them.
One of the important aspects of the solar cell is its temperature. Thus,by heating one element only one degree higher than normal (25C)it may lose a voltage of about 0,002 V, i.e.,° 0.4% / degree. Figure 5.3 shows the IV characteristic curve for temperatures25ofC and 60C.
In a sunny day sufficiently different elements can be heated up to 60-70°Cand thus save 0.07-0.09 each. This reason is one of the main ones in the case of a voltage drop, and as a consequence, and a drop in the efficiency of the solar cell.
The efficiency of a conventional solar cell currently ranges from 10-16%. This means that an element with a size of 100 * 100 mm under standard conditions can generate 1-1.6 watts.
All photovoltaic systems can be divided into two types: autonomous and connected to the electric network.
An autonomous system in the general case consists of a set of solar modules located on a supporting structure or on a roof, a storage battery (battery), a discharge controller — a battery charge, connecting cables. Solar modules are the main component for building photovoltaic systems. They can be made with any output voltage.
For ground use, they are usually used to charge rechargeable batteries (batteries) with a nominal voltage of 12 V. In this case, as a rule, 36 solar cells are connected in series and sealed by lamination on glass, textolite, and aluminum. The elements are located between the two layers of the sealing film, without air gap. The technology of vacuum lamination allows to fulfill this requirement. In the case of an air gap between the protective glass and the element, the reflection and absorption losses would reach 20-30% compared to 12% without the air gap.
The electrical parameters of the solar cell are represented as a single solar cell and a current-voltage curve under standard conditions (Standart Test Conditions), i.e., when solar radiation is 1000 W / m2,a temperature of – 25°Cand at a latitude of the solar spectrum 45of( AM1.5).
The mean value for the operating voltage of the module, which consists of 36 elements, will be from about 16 to 17 V (this is approximately 0.45 … .0,47 In one member) at a standard temperature 25of C.
Thus, when heated in real operating conditions, the modules are heated to a temperature of 60-70°C,which corresponds to the displacement of the working point voltage, for example, for a module with the operating voltage 17 V – with values of 17 V to 13,7-14,4 V (0,38-0, 4 V per cell).
Based on the foregoing, we must approach the calculation of the number of module elements connected in series. If the consumer needs to have an alternating voltage, then an inverter-converter of direct voltage to alternating voltage is added to this kit.
Under the calculation of FES refers to the determination of the rated power of the modules, their number, connection diagrams; choice of type, operating conditions and battery capacity; inverter and charge-discharge controller capacities; definition of parameters of connecting cables.
First you need to calculate the total power consumption for all possible consumers. The consumer power can be found in the product passport. At this stage, you can choose an inverter, for this it is enough to increase the power by 1.3 times at least. But it must be borne in mind that some consumer devices, such as a refrigerator, at the time of start-up consume power 2-3 times more than the nameplate. For powerful stations (more than 3 kW), the inverter voltage must be at least 48 V, because inverters cope well with large voltages, thereby reducing losses.
Calculation of power consumed by consumers. When calculating a solar power plant, the first thing to do is to make a simple list of electricity consumers. Calculate how much power each consumer consumes, how much voltage, and accordingly add to the table.
Consumers of alternating voltage (in our case, consumers from No. 1 to No. 4, and No. 6 from the table) are connected to the inverter, and constant consumers (lighting No. 5 and some other consumers No. 7 from the table) directly through the charge controller. In this system under consideration, a bus with a voltage of 24 V corresponding to the voltage of the ASE battery is taken as the main bus.
After that, you need to find out how much time in hours a particular consumer works per day. Then, multiplying the consumer’s power by the entire time of its operation, we will determine how much this load of electricity consumes daily. Thus, build a table of energy consumption per day.
Daily energy consumption table
Load
Power, W
Voltage, V
Operating time, h / day
Consumption, VT · h / day
1 Kettle
1000
220
0.5
500
2 Microwave
1300
220
0.25
325
3 Refrigerator
250
220
12
3000
4 TV
100
220
6
600
5 Lighting
100
24
6
600
6 Laptop
70
220
5
350
7 Other consumers
100
24
3
300
Total
2920
5675 A
solar power plant can supply many energy consumers with the condition that the total energy of the consumers will not exceed the power of the solar power plants. The list of consumers contains loads operating either continuously (lighting) or intermittently (kettle, television). But also, loads that work inconsistently are divided into two categories, some work with a fixed interval, while others work with a floating interval (for example, like a refrigerator from the table).
Therefore, it is important to correctly determine the total output power of a solar power plant. To reduce the cost of solar cells, it is also necessary to build a schedule of changes in load consumption per day, that is, compile a table by time and enter the time of the load. It is important to ensure that several consumers with high power or a large number of consumers with low power are not simultaneously turned on. When constructing such a schedule, it is very difficult to understand exactly when a consumer with a floating load is turned on (refrigerator, table). To be sure to protect yourself, and not to miss, we assume that such consumers are constantly working.
A practical guide to the installation of load-bearing structures.
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Installation of solar panels has a specially developed installation technology. In addition, there are several important requirements regarding the installation process.
Photovoltaic modules should be placed in the most lit place. This may be the roof of the object, the facade or the area near the house. The presence of dimming even a small part of the surface of the photovoltaic module is unacceptable.
Solar panels should be installed on the south side of the roof of a residential building. In this case, solar radiation that enters the surface of the module will have maximum performance.
During installation work, the angle of inclination of the photovoltaic module should be taken into account. If the panels are installed with their own hands, then the angle of inclination should be close to the horizon. For different geographical areas, the angle of inclination of the panels is different. It should also be noted that periodic changes in the angle of inclination of the surface can increase productivity. In the summer, the angle should be done more by 12 degrees. While in winter, it should be reduced by the same 12 degrees. If such manipulations are not possible, then the installation angle of the panels is chosen optimal in accordance with the indicators of the geographical latitude of the region.
The location of solar panels plays an important role in servicing solar power plants. When the photovoltaic modules are installed on a personal plot, the distance from the surface of the panel to the soil should be at least half a meter. This will eliminate the possibility of overlapping the surface with precipitation in the form of snow. If the solar panels are planned to be used only in the summer, then raising them above the surface of the earth is not necessary.
An important point in the installation of roof solar power plants is to take into account the type of roof.
The roof of each individual object has a number of individual features that can determine the further installation technology. It should be noted that even the color of the roof plays an important role. If the roof of the building is dark, then it is most susceptible to strong heat. If you install photovoltaic modules on such a roof, then overheating of the surface cannot be avoided. On such roofs before installation, a special coating of light shade is installed.
Installing PV modules on flat roofs Installing
solar modules on this type of roof is easy. We can say that this type of surface is the most suitable for installing panels. Successful installation in this case is achieved through the acquisition of special support frames. They should be installed in a southerly direction and the modules should be fixed on their surface at a set angle. If the calculated capacity of the power plant is high enough and the roof area is small, then multi-tier support frames will be the best option.
The installation of the panel on the surface of a sloping roof
This type of surface for installing the solar module involves installation using a special type of mount. As a rule, they come complete with solar panels. These installation work involves the mandatory accounting of the material from which the roof is made. This will optimally select the mounting structures that are specially designed for various types of roofs. Their mutual replacement is excluded.
During installation work on the surface of an inclined roof, special attention should be paid to the fact that a clearance must be established between the electrical module and the roof surface. It is necessary to ensure free air circulation. Thus, the panel itself can be cooled naturally.
Between the rows of installed photovoltaic modules it is imperative to maintain a distance. This condition avoids the shadowing of the lower modules by the upper ones. In this calculation, you should focus on the size of the row, that is, the height of the module. The row spacing should be at least 1.7 of the panel height. In addition, there is a need to make gaps between the row modules. This allows you to make the installation process more convenient and facilitate the process of connecting the station, and carrying out maintenance work in the future.
An important role in the installation of solar panels is played by the length of the patch cables. The longer the cable, the higher the energy loss of the station. This applies to the connection of neighboring modules, as well as the cables that connect the array of panels with other devices of the station.
For example, the cable connecting the energy storage device to the charge controller should not be longer than four meters.
When carrying out installation work, it should be borne in mind that the photovoltaic module is fixed at four points. You should also pay attention to the fact that most often there are supporting structures in which fasteners are carried out along the long side of the module. This means that the position of the panel will be vertical.
Often, clamp type clamps are used to attach the module. In addition, for this purpose, bolts that are fixed along the edges of the supporting structures are suitable. Any mounting option involves the use of a narrowly targeted device that is designed for a specific type of installation. It is impossible to replace them at your discretion with others.
Making mistakes during installation work and installing a poor-quality photoelectric module can provoke a fire. In the accessibility zone, not far from the array of solar modules, a fire extinguisher should be located.
Installation of photovoltaic panels implies their reliable and fixed installation on load-bearing structures in a correctly defined direction. In this case, metal structures can either be firmly fixed or with the use of tracking systems.
Installation of tracker systems increases the efficiency of solar modules by 30%. Such load-bearing structures are a movable frame, which periodically changes the angle of inclination of the surface of the solar panel to follow the sun.
Special sensors are installed on the surface of the frame, which allow you to track the position of the sun and thereby increase the level of productivity of the solar station.
The financial costs of acquiring tracking systems are higher than with the purchase of fixed load-bearing structures. It should be noted that increased investments make it possible to increase income from the sale of electricity by increasing generation volumes.
When choosing the optimal tracking system, an individual role plays an important role. Different regions suggest a certain level of cloudiness and light exposure on the surface of solar panels. Depending on these indicators, the selection of optimal load-bearing structures for photovoltaic modules is carried out.
Next, we will consider a clear algorithm for installing photovoltaic modules on the roof of a residential building.
Earlier, we noted that the dark color of the roof of the house leads to overheating of photovoltaic panels. To avoid this, before starting installation work, you should install a light base on the roof. For this purpose, the best option is a light barrier. It will provide the roof with protection against excessive humidity and eliminate the likelihood of overheating of the solar panel. It should be noted that the installation angle of the photovoltaic module should be 30 degrees.
Before the immediate start of installation work, it is necessary to mark the roof. Marking will reduce the installation time of supporting structures and greatly simplify installation. The racks should be located in parallel, and the distance between them should be at least 1 m. The brackets are fixed directly to the roof by an anchor wedge or dowel. Its most suitable size is 6×65.
The installation procedure for this item is simple and fairly clear:
Initially, it is necessary to make a hole of a suitable diameter.
The holes should be filled with special grease. In its role, solidol or similar compounds may act.
The next step is to install the anchor.
This method of fixation is the most reliable, since the anchor wedge is used to install metal structures on a brick or concrete base. Accordingly, this kind of fastening is able to withstand this kind of load.
An anchor wedge is fixed to the surface of the roof support rail, which holds the metal tile. If the roof is made of concrete, then installation work becomes much easier. This type of roof involves the installation of anchors in a meter from the next. In addition to the anchor, an 8×65 dowel can be used.
A likely option is also the use of roofing material. An important aspect is the presence in it of fiberglass, which has such properties as: small indicators of weight, stability, strength, ductility. This material can be used on the roof surface of various architectures and with a different angle of inclination.
It should be noted that installation is carried out in warm weather in the absence of high humidity.
In addition, special attention must be paid to the preliminary preparation of the surface for fastening. Initially, you need to clean up dirt and debris. The surface of the roof must be level. At the preliminary stage of preparation, degreasing of the surface material is carried out. You can use White Spirit as a degreaser. In addition, attention must be paid to the surface primer.
After all the above measures, it is necessary to lay the pre-heated roofing material on the surface of the bracket. It is important to note that the ruberoid coating should extend beyond the edge of the part by 5 or more centimeters. Continued installation will be possible only after cooling of the roofing material. Full cooling is not required, but a slight temperature reduction is necessary.
Next, the rail is mounted on the bracket. The best option is to use a galvanized profile. Its creation involves the use of hot dip galvanizing. This allows you to create a protective coating, the thickness of which is from 70 to 150 microns. This option eliminates the likelihood of rust and significantly extends the life of the supporting structures.
In order to avoid corrosion changes, aluminum fasteners should be preferred.
After installing the main structure, you can proceed to the installation of the cable part of the solar panels.
The DC cable should be laid under the metal structure. Cables serve as the connection of all solar panels with subsequent access to the switch and inverter. We attach the wires to the back of the profile with plastic clamps for ease of installation and to avoid environmental influences.
The solar panel itself is mounted on a galvanized profile such as “ LS-PROFI ”, which tolerates the vagaries of the external environment and does not lend itself to corrosion, which is extremely important for this process.
The profile is fastened with a bracket, with one side to the rail, and the other to the roof. All connections must be mounted with galvanized bolts (M8 or the like) using a drill or hammer.
It should be noted that when connecting, do not rush. It is necessary to fix the profiles between themselves with a nut and an M8 bolt, while creating a strong and reliable connection.
Rules for the operation of photovoltaic modules
Regular maintenance and maintenance of photovoltaic modules and other components of a solar power plant is the key to a quick return on financial investments in the installation of the facility. Devices requiring increased attention include electric cables, charge controllers, inverter units, energy storage devices, and electrical equipment.
If a specialist who is responsible for setting up the system and monitoring is attached to a solar object, the probability of the most productive and long-term operation of the devices is significantly increased.
A well-established power plant monitoring system plays an important role in maintenance. If this process is carried out comprehensively and professionally, the likelihood of breakage or malfunction is significantly reduced.
The process of assessing the life of solar power plant is characterized by the presence of certain parameters:
Assessment of the state of the fastening of the components of the system of photovoltaic modules. If the fasteners are loose, for some reason missing or there are traces of rust, this will lead to failure of the system.
The importance of the current state of an individual module. Construction work involves checking each individual panel for operability. It should be remembered that the failure of one solar panel leads to tangible losses in generation.
Checking inverter installations for dust or excessive increase in temperature. If the inverter ventilation cooling system is cleaned regularly, then the life of the power plant increases markedly. In this case, the efficiency of the object does not tend to decrease. Such events should be carried out with any inverter, even one intended for outdoor installation in regions with bad weather conditions.
The presence of grounding. The safety indicators of any object associated with electrical equipment directly depend on this parameter. Verification of contact safety and insulation should be carried out systematically.
Check electrical wiring. The time of return on financial investments and the overall productivity of the plant is directly dependent on the serviceability of even such small elements as wires. Their condition, reliable connection and the absence of mechanical damage allows maintaining the set generation level without energy loss.
Features of the location of the stations. A system of solar modules should be available for maintenance and repair work.
Keeping clean. Photovoltaic modules that are free from pollution and dust can produce up to 20% more energy than those that are not properly maintained.
Manufacturers of photovoltaic modules declare as recommendations that planned activities in relation to system components should be carried out at least once every six months. In real conditions, the regularity of such events directly depends on the region where the solar power plant is located and the features of its work.
The future owner of a solar power plant should clearly understand that timely maintenance of the plant on a regular basis eliminates the possibility of defects and expensive repairs in the future.
In addition, you should pay attention to the fact that the purchase of solar panels of dubious quality, but at a reduced price, will soon lead to additional financial investments. The most economically feasible would be the acquisition of solar panels in which the price-quality ratio will be optimal.
This material is allowed to be used for educational purposes.
A solar power plant is an object for generating electricity through the use of solar energy.
The work of power plants can be carried out in 3 modes:
an autonomous mode takes place when the solar power station does not have access to other sources of energy, except for solar radiation;
The standby mode of a solar power station is a feature of operation in which the central network is a fundamental source of energy and the solar power station is an auxiliary.
The hybrid mode of operation involves a combination of the use of energy from a common network in addition to the energy generated by a solar power plant. This mode of operation is most appropriate when the central network undergoes an overvoltage or malfunctions are observed in it.
The production of electricity using solar power plants is currently quite a popular area in renewable energy. This production allows us to provide consumers with electric energy without reference to a common network, receiving energy from solar radiation and transforming it into alternating current.
The components of a solar power plant include:
photovoltaic modules;
charge controller;
inverter installation;
energy storage unit (battery).
The uninterrupted operation of a solar power station is ensured by the operation of all these components as a single system.
Structural Components of solar power plant
Let us consider in more detail the component parts of any solar power plant.
Solar module
The integrated single array of photovoltaic modules is the center of the solar power plant. The array of solar panels fully determines the amount of electricity generated by the solar station.
The solar panel or FEM transforms the energy flux of sunlight into electric current. The efficiency of a conventional photovoltaic module is in the range of 10-35 percent. Advanced models can show efficiency results of 45% and higher.
The principle of operation of the solar power plant, which is based on solar panels, is quite simple and understandable. Photovoltaic modules are combined into a single array, the control of which is carried out by the social block of the solar power plant. A solar battery with a sufficient amount of radiation generates a constant electric current. Thanks to the inverter installation, it is transformed into a variable and supplied to the consumer. The amount of energy produced above the norm accumulates in the battery. Photovoltaic modules are divided into several types. This separation is based on the consideration of silicon compounds in the composition of the panels.
There are three main types:
single-crystal panels;
modules consisting of polycrystals;
amorphous panels.
It should be noted that it is the presence of silicon compounds in the composition of the photovoltaic module that makes it possible to create a “pn” junction. It is this transition that allows you to transform the sun’s rays into electrical energy.
An important parameter of the efficiency of the solar panel is the material of which it consists. Monocrystalline modules have the longest life and are characterized by a high level of stability. The power of such a solar panel for 5 years is reduced by 5-10 percent. Among the minuses of this type of modules can be distinguished increased fragility and reduced indicators of the mechanical strength of the device. At the same time, the cost of such a photovoltaic module is the highest of all the presented types.
Polycrystalline modules have a lower cost, but at the same time they have a reduced stability of the output power. The efficiency of such modules does not exceed 30 percent.
The latest scientific methods make it possible to produce modules from silicon compounds of amorphous structure. Such modules are called thin-film. The life of such solar panels is about 10 years. The coefficient of performance in this case is 10%. The advantages of amorphous panels are the low price and low weight of the modules.
Charge controller
Charge controller is one of the most important links in the composition of solar power plants, which performs a number of special functions. Firstly, the controller adjusts the voltage, which is an array of photovoltaic panels. Secondly, this device controls the correctness and productivity of the energy storage charge. This allows you to avoid raising or lowering the charge level, save it within the permissible norm.
This device connects the photovoltaic module with an energy storage device.
Functions of the charge controller:
the implementation of the connection of the photovoltaic module to charge the battery in automatic mode;
the product of the charge of the energy storage unit, including many stages;
disabling the photovoltaic module after a full battery charge in automatic mode;
in case of exceeding the established norm of the discharge of the battery, the product of shutdown in automatic mode;
the product of reconnecting the load in order to charge the battery.
All the above functional features play an important role in the process of preserving the energy storage efficiency and preventing its premature failure, which significantly reduces the cost of servicing a solar power plant. If the battery is recharged on a regular basis, this will lead to boiling of the electrolyte. Accordingly, there will be expansion of the sealed structure of the device.
The opposite process – an excessively high level of battery discharge, is also dangerous. This process can lead to sulfation of the drive plates and its complete failure. Lead-acid batteries are most susceptible to breakdowns in the event of an uncontrolled charge-discharge. They are most often installed in traditional solar systems.
Varieties of popular charge controllers:
a device with pulse-width modulation;
device with the search for the maximum power point.
The types of controllers that were used earlier had the ability to disconnect the battery from the photovoltaic module causing a short circuit. For photovoltaic modules that do not tolerate shorting, the use of this type of controller was unacceptable. This significantly limited their scope.
A device with PWM (pulse width modulation) is characterized by a process sequence that allows you to charge the battery by 100%.
There are four main stages of the charging process using a similar controller:
The implementation of the main charge. At this stage, the battery is transferred the entire volume of electric current from the module.
The implementation of an absorbing charge. This stage involves maintaining a certain battery level. Thus, the controller eliminates the possibility of increasing the temperature of the drive above the norm and the formation of gases inside the structure. The amount of incoming electric current decreases depending on how charged the drive is.
The implementation of a support charge. At this stage, the controller allows you to save charge after the battery is 100% charged. Also, the incoming current is reduced to avoid overheating.
The implementation of a balancing charge. This stage is only possible for open batteries. When charging, equalization occurs, accompanied by large gas evolution. This process involves the formation of hydrogen and oxygen. To prevent the battery from exploding, provide an adequate level of ventilation and secure the device by placing it away from the source of fire.
Most charge control devices are programmed to use the factory default settings. It is they who regulate the switching of charge-discharge modes. It is best to give preference to controllers that are customizable. In them, you can select a specific battery capacity, charge voltage indicators, which are recommended by the manufacturer of the energy storage device.
Selection of the charge controller is carried out in an individual mode specifically for each solar power plant. In this case, the power parameters of the photovoltaic panels and the load as a whole are taken into account. Before putting the solar panels into operation, you should carefully read the manual and technical description for the most successful selection of the controller.
Battery, solar power is also a very important link. Its function is to accumulate and conserve electricity, which was generated by solar power plant. An autonomous system of solar power plants involves the use of special batteries, the service life of which is the longest.
Battery
An energy storage device (battery) acts as a buffer that accumulates electricity using the reversibility of chemical reactions. The cyclic mode of operation of the drive is due to the chemical processes occurring in it that provide charge and discharge. The charge process involves passing an electric current in the opposite direction to the discharge process.
If drives are combined into blocks, then they are characterized as batteries.
The characteristic of energy storage is capacity as the main parameter. This parameter represents the largest allowable charge level that a certain type of drive can withstand. In order to measure the capacity of the drive, it should be discharged for a specified time to the specified voltage indicator.
Energy storage devices, which are used in various types of power systems, have a number of specific differences with respect to:
rated voltage indicators;
sizes;
capacitive characteristics;
types of electrolyte;
availability of resource indicators;
the speed of the full charge
pricing policy;
indicators of operating temperatures, etc.
There are certain requirements for energy storage in solar systems:
The battery must have a high cyclicity, that is, withstand as many charge-discharge cycles as possible.
Preference is given to devices having a small self-discharge.
The charge current should be high.
The battery for the photovoltaic system should have a fairly wide range of temperature conditions, within which its effective operation is carried out.
An important aspect is the lack of special requirements for the maintenance of the device.
Taking into account all of the above requirements, deep-discharge energy storage devices have been created that are suitable for different types of electrical supply systems.
For installation on photovoltaic stations, there is a special modification of such batteries called solar. These devices have the highest resource indicators during the work on cycles.
The starter drive in this mode of operation is not effective. Starter batteries do not tolerate deep discharge or low current charge. In addition, they are characterized by an increased level of self-discharge.
The life of such devices is relatively small. As a standard mode of operation, these devices use a short-term discharge using high current with subsequent restoration of the charge level. Then they are put into standby mode for starting the starter. The battery charge at this time is maximum.
For clarity, you can compare these types of batteries with runners. In this case, the starter drive is a sprinter. A specialized battery is comparable to a marathon athlete.
The most popular at the moment are energy storage devices based on lead-acid. Their popularity is justified by the reduced unit price of 1 kW / h compared to similar devices. Such drives have a higher efficiency and a wider range of operating temperatures. For example, if the performance indicators of a lead-acid storage device are about 80%, then an alkaline storage device has no more than 60 percent according to these parameters.
Some characteristics of alkaline batteries allow them to exceed lead acid. Firstly, alkaline drives have a longer resource in the duration of operation. Secondly, there is a chance to restore the operation of such a battery due to a change in electrolyte. Thirdly, alkaline batteries can function effectively at low temperatures. At the same time, many parameters of this type of storage devices make them unsuitable for use by photovoltaic stations. Among them:
low coefficient of performance;
reduced susceptibility to charging with low current.
The final link of the constituent solar power plants is an inverter installation. Inverter is called special equipment for a solar power plant, which transforms direct current into alternating current. In this case, the parameters of the magnitude and frequency of the voltage change.
The inverter perceives electricity coming from the drive through a special input. The inverter also receives energy that is supplied through the controller from the photovoltaic modules. The main function of the inverter is the conversion of direct current to alternating current. It is alternating current that is used in the future for the energy supply of a residential building or other energy consumption facility. The inverter installation is selected according to the power that is in demand by household appliances. The inverter power in watts is measured. The most popular for use in home solar power stations are inverters with a sinusoidal waveform. In order to meet the energy needs of a residential facility, the performance of the inverter installation should be within 2-4 kilowatts.
Most often, the inverter is presented in the form of a periodic voltage generator. The shape of the inverter installation is close to sinusoidal. Within the photovoltaic station, the inverter acts as one of the central links in the system.
Given the fact that the efficiency of the photovoltaic module is within 30%, the use of an inverter installation with a low efficiency will significantly reduce the efficiency of a solar power plant. This combination makes the work of solar power plant economically inexpedient and unprofitable.
An inverter installation as part of a solar power plant can operate as a single device or be included in the equipment of uninterruptible power supply systems.
Next, we will consider standard types of solar power plants, depending on how they function.
Autonomous solar power plant
A solar power plant characterized by an autonomous mode of operation that does not have a connection to a common electric network is called autonomous. This type of power plant is used in cases where the ability to connect to the power line is absent. Autonomous solar power plants are widely used in remote regions and have become an alternative way to meet the energy needs of residential facilities. Among the obvious advantages of autonomous solar power plants, a significant drawback is the total cost of equipment and installation, the difficulty in calculating the necessary loads.
It should be noted that in case of interruptions in the work of the autonomous solar power plant, it will be impossible to resume energy consumption through the use of a common network. The power of a solar power plant of this kind should be calculated based on the energy consumption of household appliances in a residential facility. This will fully satisfy the energy needs of the house.
An important fact is that an autonomous solar power plant must fully provide the energy needs of a residential building. That is, the entire amount of electricity that household appliances will consume must be generated by photovoltaic panels. At night and in cloudy weather conditions, energy consumption at home will be ensured by the operation of the battery.
The number of photovoltaic panels for an autonomous solar power station should be calculated on the condition that energy should be fully enough for the consumed power of a residential building and the full charge of the battery. In addition to providing energy to residential facilities, such solar power plants can be used to provide power to powerful equipment during repair and construction work in the field.
In order to increase the efficiency and the most productive use of the power plant, it is necessary to develop a clear work plan that allows to increase the performance of the system. For this, the following aspects should be worked out most carefully:
required power at a certain time of the day;
how much energy a solar power plant can provide at a given time;
what power indicators can be provided by the battery;
what will be the final price of electricity coming from all structural units of the solar power system.
The backup power supply solar plant
In many settlements remote from large cities, there is not always a satisfactory level of energy supply. Frequent network interruptions force us to look for alternative methods. One of these methods is the power supply system.
This mode of operation does not imply the use of photovoltaic modules on an ongoing basis. The energy storage device (battery) is 100% charged and arrives in standby mode. If in the general network a failure occurs or the voltage does not meet the required parameters, the backup power system is connected. At this moment, the inverter is converting the direct current from the energy storage device into alternating current.
Uninterrupted power supply becomes possible precisely thanks to such a scheme of work. The capacity of the battery acts as a limitation in this mode of operation. It is this parameter that determines the time of power supply from the backup power system.
The reserve solar power station operates only in emergency cases when the supply of electricity from the common network becomes impossible. The main aspect of the efficiency of the backup power system is the number of batteries.
There is a variant of the backup type solar power plant, in which the process of charging the battery is carried out at a time when the photovoltaic module generates excess electricity. To prevent the battery from losing its charge while abstaining from recharging system devices, there is a charge controller. He is involved in the regulation of these processes.
The function of the controller is to monitor the process of ensuring the set charge level of the energy storage device. This significantly increases the life and productivity of the battery.
Grid type solar power plants
Network solar power plant as a structural component includes a network inverter installation and photovoltaic modules. The inverter is used to carry out the process of direct transformation of direct current received from photovoltaic modules into alternating current. It should be noted that the frequency of the alternating current is 50 Hz, and the voltage is 220 volts. The inverter is connected in parallel to the common network.
In this case, the generated energy is supplied to the power grid and is used primarily. If the solar panels do not produce enough electricity, then the energy supply of the house is provided by energy from the network.
Network solar power plant uses the battery only in case of power outages. This advantage significantly reduces the financial investment of the consumer.
It should also be noted that the electricity produced by the photovoltaic modules is supplied to the consumer through an inverter immediately after generation.
The amount of energy produced is directly proportional to the intensity of solar radiation. When a grid solar power station works in tandem with a common grid, the priority is given to electricity produced by photovoltaic panels. This means that with a sufficient amount of insolation, energy from the common network is not used absolutely. If the level of insolation is insufficient to ensure the energy needs of a residential building, then exactly the amount of energy that is missing is supplied from the network.
Basics of building a power plant
The construction of a solar power plant involves the preliminary creation of a program. This approach allows you to create a clear algorithm that will detail each main process in construction.
The most important points of the program will be:
territorial coordination, that is, the approval of the area on which the solar power station will be located;
creating a safe environment for staff and the operation of the facility as a whole;
development of a construction fund;
the installation of photovoltaic panels;
installation work on the collection of structures;
construction work at substations;
electrical work on the specified site;
connecting the power plant to a common network;
testing and starting a solar power plant.
An important aspect in planning the construction of a solar power plant is the price control of the object. A solar power plant project will be considered viable if the costs of its construction are well thought out and reasonable.
It should also be noted that the owners of solar power plants most often resort to the services of a contractor company, which carries out engineering work for the further design and construction of the facility. Warranty obligations within the framework of the agreement between the contractor and the solar power plant owner are provided on photovoltaic panels, a guarantee of the volume of energy production, on the capacity of the solar power plant as a whole.
In addition, during installation, a prerequisite is the quality control of the work performed.
Next, we will consider which format of a solar power plant is most suitable for private home ownership.
For the energy supply of a residential building and for the sale of energy balances at a green tariff, the most suitable type of solar power plant would be a network.
Often people who are interested in the process of installing solar power plants on the territory of a private house ask themselves what the cost of equipment for a residential building will be, for example, with an area of 100 square meters.
It should be noted that the price of equipment is directly dependent not only on living space. In this case, a different calculation method is used.
Before deciding to install a solar power station, the installation site should be inspected by a specialist. Only he will be able to give an opinion on whether the technical conditions of electric networks correspond to the installation of solar modules. The required power is estimated in kilowatts for a specific residential facility.
The maximum allowed power of a home solar power plant is 50 kW. This is the limit that is allowed for purchase in Oblenergo. If the owner of the house decided to install a solar power plant with a capacity of 50 kW, then he must bring a cable of the corresponding capacity to the residential object. In accordance with the specified conditions in the future, all technical parameters are calculated.
The next step in installing a solar power plant is the installation of equipment and the commissioning of a complete system. Only after this, documentary confirmation and drafting of an agreement regarding the supply and sale of electricity to Oblenergo is carried out. Then you need to open a bank account, which will be credited with the proceeds from the sale of surplus electricity.
The last step in this algorithm is to connect the green tariff and make a profit from your home solar power station.
The process of installing a solar power plant, together with the paperwork, can take about 30 days. Timing can be delayed if the nominal power of the energy network of a private house is about 5-10 kW. In this case, the owner of a private house should visit the distribution zone and draw up a statement, on the basis of which the relevant authorities will give permission to install a more powerful cable.
An important factor that interests future owners of solar power plants is the payback period of their investments. In Ukraine, given the level of insolation, these lines can vary from 5 to 7 years.
If a solar power plant with a capacity of 10 kW is installed in a private household, then the payback period will be approximately 6-6.5 years, if the power of the power plant is 30 kW, then the invested funds will be repulsed in 5-5.5 years.
Regarding revenues from a solar power plant of a private nature, we can say that this amount is in the range of 10,000 hryvnias for 1 month.
It should also be noted that generating electricity just for the purpose of providing energy to your home is not very profitable. Today’s green tariff allows you to sell residual energy into the network at a price that is 6-7 times higher than the price consumed.
The amount of solar radiation most affects the amount of energy produced. For example, if you own a solar power station in Transcarpathia, then the insolation rate will be within 1100 watts. If you install a solar power station in a private house in the Odessa region, then these figures will increase to 1500 watts. The more sunny the region is, the faster the project will pay off.
The period of the highest solar activity, as a rule, begins in the month of May and ends in September. The average value of the volume of electricity generated by a solar power plant during the day is about 90 kilowatt hours.
How many photovoltaic modules are needed for a 30 kilowatt solar power plant?
If we take into account that one solar module has a power of 250 watts, then for such an solar power plant 120 modules are required.
Now the installation of solar modules in apartment buildings is gaining popularity. The only condition for the success of such an event is the presence of a powerful wiring. In addition, when designing a solar station of this type, the roof area of the object is taken into account. Poor roof sizes can be a limiting factor. Photovoltaic modules have different capacities, so if the roof area is small, the installation of more powerful panels in a smaller quantity will be an excellent output.
At the moment, the state provides all kinds of support to owners of home solar power plants. State-owned banks, including Oschadbank, offer customers favorable credit conditions for the purchase of solar power plant equipment.
Many factors in the architecture of a residential building can become a barrier to the installation of a solar power station. The reason for this may be the complex construction of the roof; orientation of slopes, unsuitable for installing panels; poor shading interference (this may be a chimney, ventilation outlet or window). Despite the above factors, the ability to install a 30-kilowatt solar power station is still present.
Installation becomes possible if there is a site on the territory of the household, the meter of which allows you to install photovoltaic modules on it.
The increased interest in terrestrial solar power plants arises due to the often encountered limited roof area. The average static private residential facility, even having a suitable roof, the total area of which reaches 100 square meters, allows you to install up to 15 kW of rated power.
If you install photovoltaic modules on the plot, the total capacity of which will be 30 kilowatts, the profit from the sale of electricity will be about 5,000 euros for 12 months. This is provided that the residential facility will consume about 5 hundred kilowatt hours per month. The time it takes for an investment in a home solar power plant to return to its owner is about six years.
Installation of a home solar power station is not a complicated task from a technical point of view. Minimization of time costs, elimination of incorrect calculations and work defects occurs due to the involvement of professional solar installers.
The most important conditions to be observed when installing a solar power plant on a land plot are the southern orientation of the photovoltaic modules and the exclusion of shading objects. An important factor is the placement of photovoltaic modules. The inability to install the modules in one row can be leveled by careful attention to the plan and the placement of the rows of panels in such a way as to prevent mutual shading. Although this approach will require a larger area, it will provide greater productivity of the solar power plant.
A private solar power plant, with a capacity of 30 kW, averages about 500 square meters. The area also depends on the angle of the modules.
The complexity of installing a ground or roof power plant is determined by the presence of standard designs. If at the preliminary stage of designing a power plant, which will later be located on a personal plot, the construction was carried out and the necessary calculations of certain loads were carried out, then installation on the ground will take a minimum time. In this case, the design will consist in determining the optimal location of the “tables”, that is, the supporting structures that will directly hold the solar modules. If the installation of solar panels is carried out on the roof of the building, then the location of the photovoltaic modules and the process of compiling a complete set of equipment takes the maximum amount of time.
When the installation of a ground-based solar power station is carried out using equipment that is not typical, the construction time is delayed, and the process itself is much more complicated.
The installation time of a solar power station on a personal plot is determined by a number of factors: the
availability of a detailed plan of the territory;
land relief features;
the presence of communications that are underground;
geological conditions of the regions;
preliminary approval of the established location of the supporting structures for photovoltaic modules;
establishing the total capacity of a solar power plant.
If the installation of a typical table design is not possible, then some time will be required for the process of developing an individual configuration.
The typical design of a table for installing a solar panel is a special profile. The most suitable material for creating supporting structures is galvanized iron or aluminum. In addition to the weight of the photovoltaic module, a typical load-bearing structure must be designed for additional loads. In the design process, the probability of the influence of snow, rain and strong gusts of wind on the surface of the solar panel is taken into account.
The best option for creating a supporting profile for solar panels is a steel structure. To increase the wear resistance, it is better to process the structure using the hot galvanization method. A thick layer of zinc in this case will not allow the appearance of rust for many years. The galvanizing process will also reliably protect the design slots.
The installation of a private solar power station is as follows:
structures and parts are transported to a personal plot, where the installation of a solar power station will take place;
components are assembled by type of constructor according to the requirements of project certificates.
The cost of installation work on installing a solar power station
The price of installation work varies within 10% of the total estimate of a solar power station. It should be noted that the quality of the supporting installations directly affects the duration of the solar power plant and the security of financial investments in the future. Professional designers can greatly simplify the installation process and reduce the time of construction work without compromising the quality of the project. Thus, it will be much easier for the performer of installation work on the ground to work according to a previously developed plan than to improvise.
When installing a ground-based solar power station, the foundation is key. As the foundation can be used:
ballast structures, consisting of reinforced concrete blocks;
traditional foundation made of concrete;
a special base made by digging piles from metal into the ground.
From the point of view of speed and manufacturability, the foundation of metal piles is the most suitable. To create such a structure, it is necessary to use special equipment and machinery that will ensure the correct introduction of piles into the ground. The depth at which the pile should be located is about one and a half meters.
The creation of such a foundation with the necessary technological support can take several hours. Further, on this basis, installation of structures can be carried out.
If the option with a concrete foundation was chosen, then the installation work is better to postpone until the next day. Concrete requires a certain hardening time.
Provided the foundation is ready, installation can take about several days. Such a period of work is possible with standard designs. Installation of supports and installation of photovoltaic modules is fast enough. A separate sector of work with increased responsibility is the installation of inverters and cable connections. It should be noted that these activities can be carried out simultaneously with the installation of solar panels.
Installation of a solar power plant with a capacity of 30 kW can be carried out with the professionalism of workers for 4 days. This process involves a full range of construction work and equipment setup.
If at the preliminary stage high-quality design was carried out, and the preparation for installation work was based on experience and a competent distribution of responsibilities, then the installation of a solar power station will occur as soon as possible and will eliminate the presence of defects.
It is important to note that the efficiency of a solar power plant in a private house can be increased up to 5% due to fixtures with a variable angle. This design feature allows you to change the tilt angle of the solar module seasonally. The owner of the power plant can perform this manipulation independently in the winter and summer.
It should also highlight the system of facade installation of photovoltaic panels. This option is most suitable for those who prefer the competent distribution of the living area of the house. Facade fastening systems are divided into two types:
those that are mounted directly on the building’s facade;
those that are attached by hanging structures.
Private solar power plants differ from commercial volumes of generated electricity. If a solar station installed in private households has the main goal – energy supply at home, then for a commercial solar power plant this goal is to profit from the sale of electricity. It should be noted that a private solar power plant also produces electricity in the general grid, only in small quantities.
