Do-it-yourself solar power plant for a 200 m2 house

There are often messages online about the fight for the environment and the development of alternative energy sources. Sometimes they even report on how a solar power plant was built in an abandoned village so that local residents could enjoy the benefits of civilization not 2-3 hours a day while the generator is running, but constantly. But this is all somehow far from our life, so I decided to use my own example to show and tell how a solar power plant for a private home is structured and how it works. I’ll tell you about all the stages: from the idea to turning on all the devices, and I’ll also share my operating experience. The article will be quite long, so those who don’t like a lot of letters can watch the video. There I tried to tell the same thing, but it will be seen how I collect all this myself.

Initial data: a private house with an area of ​​about 200 m2 is connected to the power grid. Three-phase input, total power 15 kW. The house has a standard set of electrical appliances: refrigerators, televisions, computers, washing machines, dishwashers, and so on. The power grid is no different in terms of stability: the record I recorded was a blackout for 6 days in a row for a period of 2 to 8 hours.

What you want to get: forget about power outages and use electricity no matter what.

What bonuses could there be: Maximize the use of solar energy, so that the house is primarily powered by solar energy, and the deficiency is taken from the network. As a bonus, after the adoption of the law on the sale of electricity to the grid by private individuals, begin to compensate for part of their costs by selling excess generation to the general power grid.

Where to begin?

There are always at least two ways to solve any problem: study yourself or entrust the solution to someone else. The first option involves studying theoretical materials, reading forums, communicating with owners of solar power plants, fighting internal toads and, finally, purchasing equipment, and then installation. The second option: call a specialized company, where they will ask a lot of questions, select and sell the necessary equipment, and maybe install it for some money. I decided to combine these two methods. Partly because it’s interesting to me, and partly in order not to run into sellers who just want to make money by selling something that’s not exactly what I need. Now it's time for theory to understand how I made my choices.

The photo shows an example of “using” money for the construction of a solar power plant. Please note that the solar panels are installed BEHIND the tree - so no light reaches them and they simply do not work.

What tools and materials will be needed

Along with the motor, it is necessary to purchase rectifier diodes that will convert alternating current into direct current, as well as polar capacitors.

For those who plan to charge a tablet or smartphone from a battery, you will also need a board equipped with a USB port, which will allow you to receive 5 volts, a voltage indicator that is used when charging smartphones.

Tools you will need:

• A grinder along with the necessary set of discs for working with both metal and wood, as well as a grinding disc;
• An electric drill designed for drilling metal;
• A screwdriver is necessary for the manufacture of large batteries, which require the use of a significant number of self-tapping screws (several dozen each). The screwdriver can be supplied with heads designed for a wrench or one universal head, similar to an adjustable wrench

After all the tools have been collected, they proceed directly to the manufacture of the generator.

Types of solar power plants

Let me note right away that I will not be talking about industrial solutions or heavy-duty systems, but about an ordinary consumer solar power plant for a small home. I am not an oligarch to throw money away, but I adhere to the principle of being reasonably reasonable. That is, I don’t want to heat the pool with “solar” electricity or charge an electric car that I don’t have, but I want all the appliances in my house to work all the time, without regard to the power grid.

Now I’ll tell you about the types of solar power plants for a private home. By and large, there are only three of them, but there are variations. I will arrange them according to the increase in cost of each system.

Network Solar Power Plant - this type of power plant combines low cost and maximum ease of operation. It consists of only two elements: solar panels and a network inverter. Electricity from solar panels is directly converted to 220V/380V in the home and consumed by the home power systems. But there is a significant drawback: the ESS requires a backbone network to operate. If the external power grid is turned off, the solar panels will turn into a “pumpkin” and stop producing electricity, since the operation of the grid-connected inverter requires a support network, that is, the very presence of electricity. In addition, with the existing power grid infrastructure, operating a grid-tied inverter is not very profitable. Example: you have a 3 kW solar power plant, and your house consumes 1 kW. The excess will “flow” into the network, and conventional meters count energy “modulo”, that is, the energy supplied to the network will be counted by the meter as consumed, and you will still have to pay for it. The logical question here is: what to do with excess energy and how to avoid it? Let's move on to the second type of solar power plants.

Hybrid Solar Power Plant – this type of power plant combines the advantages of a networked and autonomous power plant. Consists of 4 elements: solar panels, solar controller, batteries and hybrid inverter. The basis of everything is a hybrid inverter, which is capable of mixing the energy generated by solar panels into the energy consumed from the external network. Moreover, good inverters have the ability to prioritize the energy consumed. Ideally, the house should first consume energy from solar panels and only if there is a shortage of it, get it from the external network. If the external network disappears, the inverter goes into autonomous operation and uses energy from solar panels and energy stored in batteries. This way, even if the power goes out for a long time and it’s a cloudy day (or the power goes out at night), everything in the house will function. But what to do if there is no electricity at all, but you need to live somehow? Here I move on to the third type of power plant.

Autonomous Solar Power Plant - this type of power plant allows you to live completely independently of external power grids. It may include more than 4 standard elements: solar panels, solar controller, battery, inverter.

In addition to this, and sometimes instead of solar panels, a low-power HydroElectroStation, a wind power plant, or a generator (diesel, gas or gasoline) can be installed. As a rule, such facilities have a generator, since there may be no sun and wind, and the energy supply in the batteries is not infinite - in this case, the generator starts up and provides energy to the entire facility, simultaneously charging the battery. Such a power plant can easily be transformed into a hybrid one by connecting an external power supply network, if the inverter has these functions. The main difference between an autonomous inverter and a hybrid one is that it cannot mix energy from solar panels with energy from an external network. At the same time, the hybrid inverter, on the contrary, can work as an autonomous one if the external network is turned off. As a rule, hybrid inverters are comparable in price to fully autonomous ones, and if they differ, it is not significant.

Peculiarities

A wood-fired power plant is not a new invention, but modern technologies have made it possible to somewhat improve previously developed devices. Moreover, several different technologies are used to generate electricity.

In addition, the concept of “wood-burning” is somewhat inaccurate, since any solid fuel (wood, wood chips, pallets, coal, coke), in general, anything that can burn, is suitable for the operation of such a station.

Let us immediately note that firewood, or rather the process of its combustion, acts only as an energy source that ensures the functioning of the device in which electricity is generated.

The main advantages of such power plants are:

• The ability to use a wide variety of solid fuels and their availability;
• Receive electricity anywhere;
• The use of different technologies makes it possible to obtain electricity with a variety of parameters (sufficient only for regular phone recharging and up to powering industrial equipment);
• It can also act as an alternative if power outages are common, as well as the main source of electricity.

What is a solar controller?

All types of solar power plants have a solar controller. Even in a grid-connected solar power plant it is present, it is simply part of the grid-connected inverter. And many hybrid inverters are produced with solar controllers on board. What is it and what is it for? I will talk about a hybrid and autonomous solar power plant, since this is exactly my case, and I can tell you more about the design of a network inverter in the comments if there are any requests in the comments.

A solar controller is a device that converts the energy received from solar panels into energy digested by an inverter. For example, solar panels are manufactured with a voltage that is a multiple of 12V. And batteries are manufactured in multiples of 12V, that’s just the way it is. Simple systems with 1-2 kW power operate on 12V. Productive systems of 2-3 kW already operate on 24V, and powerful systems of 4-5 kW or more operate on 48V. Now I will consider only “home” systems, because I know that there are inverters operating at voltages of several hundred volts, but this is already dangerous for the home.

So, let's say we have a 48V system and 36V solar panels (the panel is assembled in multiples of 3x12V). How to get the required 48V to operate the inverter? Of course, a 48V battery is connected to the inverter, and a solar controller is connected to these batteries on one side and solar panels on the other. Solar panels are assembled at a deliberately higher voltage in order to be able to charge the battery. The solar controller, receiving obviously higher voltage from the solar panels, transforms this voltage to the required value and transmits it to the battery. This is simplified. There are controllers that can reduce 150-200 V from solar panels to 12 V batteries, but very large currents flow here and the controller operates with worse efficiency. The ideal case is when the voltage from the solar panels is twice the voltage on the battery.

There are two types of solar controllers: PWM (PWM - Pulse Width Modulation) and MPPT (Maximum Power Point Tracking). The fundamental difference between them is that the PWM controller can only work with panel assemblies that do not exceed the battery voltage. MPPT - the controller can operate with a noticeable excess of voltage relative to the battery. In addition, MPPT controllers have noticeably higher efficiency, but are also more expensive.

Homemade stations

Also, many craftsmen create homemade stations (usually based on a gas generator), which they then sell.

All this indicates that you can independently make a power plant from available materials and use it for your own purposes.

Next, let's look at how you can make the device yourself.

Based on a thermoelectric generator.

The first option is a power plant based on a Peltier plate. Let us immediately note that a device made at home is only suitable for charging a phone, a flashlight, or for lighting using LED lamps.

For production you will need:

• A metal body that will play the role of a furnace;
• Peltier plate (purchased separately);
• Voltage regulator with installed USB output;
• A heat exchanger or just a fan to provide cooling (you can take a computer cooler).

Making a power plant is very simple:

1. We make a stove. We take a metal box (for example, a computer case) and unfold it so that the oven does not have a bottom. We make holes in the walls below for air supply. At the top you can install a grate on which you can place a kettle, etc.
2. We mount the plate on the back wall;
3. We mount the cooler on top of the plate;
4. We connect a voltage regulator to the terminals from the plate, from which we power the cooler, and also draw terminals for connecting consumers.

It works simply: we light the wood, and as the plate heats up, electricity will begin to be generated at its terminals, which will be supplied to the voltage regulator. The cooler will start working from it, providing cooling of the plate.

How to choose solar panels?

At first glance, all solar panels are the same: the cells of solar cells are interconnected by busbars, and on the back side there are two wires: plus and minus. But there are a lot of nuances in this matter. Solar panels come from different elements: amorphous, polycrystalline, monocrystalline. I will not advocate for one type of element or another. Let me just say that I myself prefer monocrystalline solar panels. But that's not all. Each solar battery is a four-layer cake: glass, transparent EVA film, solar cell, sealing film. And here every stage is extremely important. Not just any glass is suitable, but with a special texture, which reduces the reflection of light and refracts light incident at an angle so that the elements are illuminated as much as possible, because the amount of energy generated depends on the amount of light. The transparency of the EVA film determines how much energy reaches the element and how much energy the panel generates. If the film turns out to be defective and becomes cloudy over time, then production will drop noticeably.

Next come the elements themselves, and they are distributed by type, depending on quality: Grade A, B, C, D and so on. Of course, it is better to have quality A elements and good soldering, because with poor contact, the element will heat up and fail faster. Well, the finishing film should also be of high quality and provide good sealing. If the panels become depressurized, moisture will quickly enter the elements, corrosion will begin, and the panel will also fail.

How to choose the right solar panel? The main manufacturer for our country is China, although there are also Russian manufacturers on the market. There are a lot of OEM factories that will paste any ordered nameplate and send the panels to the customer. And there are factories that provide a full production cycle and are able to control product quality at all stages of production. How can you find out about such factories and brands? There are a couple of reputable laboratories that conduct independent tests of solar panels and openly publish the results of these tests. Before purchasing, you can enter the name and model of the solar panel and find out how well the solar panel matches the stated characteristics. The first laboratory is the California Energy Commission, and the second European laboratory is TUV. If the panel manufacturer is not on these lists, then you should think about quality. This doesn't mean the panel is bad. It’s just that the brand may be OEM, and the manufacturing plant also produces other panels. In any case, the presence in the lists of these laboratories already indicates that you are not buying solar panels from a fly-by-night manufacturer.

Make or buy?

The desire to have an electric generator in your use is overshadowed by one nuisance - the high cost of the unit . Whatever one may say, the lowest-power models have a fairly exorbitant cost - from 15,000 rubles and above. It is this fact that suggests the idea of ​​creating a generator with your own hands. However, the process itself can be difficult if:

• no skill in working with tools and diagrams;
• there is no experience in creating such devices;
• the necessary parts and spare parts are not available.

If all this and a great desire are present, then you can try to assemble a generator , guided by the assembly instructions and the attached diagram.

It is no secret that a purchased electric generator will have a more expanded list of capabilities and functions, while a homemade one can fail and fail at the most inopportune moments. Therefore, whether to buy or do it yourself is a purely individual question that requires a responsible approach.

My choice of solar power plant

Before purchasing, it is worth outlining the range of tasks that are set for the solar power plant, so as not to pay for what is unnecessary and not to overpay for what is not used.
Here I will move on to practice, how and what I did myself. To begin with, the goal and the starting points: in the village the electricity is periodically cut off for a period of half an hour to 8 hours. Outages are possible either once a month or for several days in a row. Task: to provide the house with power supply around the clock with some limitation of consumption during the period of shutdown of the external network. At the same time, the main security and life support systems must function, that is: the pumping station, the video surveillance and alarm system, the router, the server and the entire network infrastructure, lighting and computers, and the refrigerator must work. Secondary: TVs, entertainment systems, power tools (lawn mower, trimmer, garden watering pump). You can turn off: the boiler, electric kettle, iron and other heating and high-consuming devices, the operation of which is not immediately important. The kettle can be boiled on a gas stove and ironed later. Typically, you can buy a solar power plant from one place. Solar panel sellers also sell all the related equipment, so I started my search with solar panels as my starting point. One of the reputable brands is TopRay Solar. There are good reviews about them and real operating experience in Russia, in particular in the Krasnodar Territory, where they know a lot about the sun. In the Russian Federation there is an official distributor and dealers by region, on the above-mentioned sites with laboratories for testing solar panels, this brand is present and is not in last place, that is, you can take it. In addition, the company that sells solar panels, TopRay, also produces its own controllers and electronics for road infrastructure: traffic management systems, LED traffic lights, flashing signs, solar controllers, etc. Out of curiosity, I even asked for their production - it’s quite technologically advanced and there are even girls who know which way to approach the soldering iron. Happens!

With my wish list, I turned to them and asked them to put together a couple of configurations for me: more expensive and cheaper for my home. I was asked a number of clarifying questions about reserved power, availability of consumers, maximum and constant power consumption. The latter actually turned out to be unexpected for me: a house in energy saving mode, when only video surveillance systems, security systems, Internet connections and network infrastructure are working, consumes 300-350 W. That is, even if no one uses electricity at home, up to 215 kWh per month is spent on internal needs. This is where you’ll think about conducting an energy audit. And you’ll start unplugging chargers, TVs, and set-top boxes from the sockets, which consume a little bit in standby mode, but still consume a fair amount of power. I won’t agonize over it, I settled on a cheaper system, since often up to half the amount for a power plant can be taken up by the cost of batteries. The list of equipment is as follows:

1. Solar battery TopRay Solar 280 W Mono – 9 pcs
2. Single-phase Hybrid inverter 5 kW InfiniSolar V-5K-48 – 1 pc.
3. AGM battery Parus HML-12-100 – 4 pcs.

Additionally, I was offered to purchase a professional system for attaching solar panels to the roof, but after looking at the photos, I decided to make do with homemade mounts and also save money. But I decided to assemble the system myself and spared no effort and time, and installers work with these systems constantly and guarantee quick and high-quality results. So decide for yourself: it’s much more pleasant and easier to work with factory fasteners, and my solution is simply cheaper.

Conditions for installing a hydroelectric power station

Despite the tempting cheapness of the energy generated by a hydro generator, it is important to take into account the characteristics of the water source whose resources you plan to use for your own needs.

After all, not every watercourse is suitable for the operation of a mini-hydroelectric power station, especially year-round, so it does not hurt to have in reserve the possibility of connecting to a centralized main line.

A few pros and cons

The main advantages of an individual hydroelectric power station are obvious: inexpensive equipment that generates cheap electricity, and also does not harm nature (unlike dams that block the flow of a river). Although the system cannot be called absolutely safe, the rotating elements of the turbines can still cause injuries to the inhabitants of the underwater world and even people.

summer kitchen with utility room under one roof

As for the disadvantages, insufficient current strength can become a serious obstacle to the productive operation of the equipment. In this case, it will be necessary to build auxiliary structures, which entails additional costs.

If the potential energy of a nearby river, based on rough calculations, is not enough to generate electricity in a volume sufficient for practical use, it is worth paying attention to methods for constructing wind generators. A windmill will serve as an effective addition.

Measuring the strength of water flow

The first thing you need to do to think about the type and method of installation of the station is to measure the speed of water flow at your favorite source.

The easiest way is to lower any light object (for example, a tennis ball, a piece of foam plastic, or a fishing float) onto the rapids and use a stopwatch to measure the time it takes for it to swim the distance to some landmark. The standard distance for the “swim” is 10 meters.

Now you need to divide the distance traveled in meters by the number of seconds - this will be the speed of the current. But if the resulting value is less than 1 m/sec, it will be necessary to erect artificial structures to speed up the flow due to elevation changes.

This can be done with the help of a collapsible dam or a narrow drain pipe. But without a good flow, the idea of ​​a hydroelectric station will have to be abandoned.

What does a solar power plant provide?

This kit can produce up to 5 kW of power in autonomous mode - this is exactly the power I chose a single-phase inverter. If you purchase the same inverter and an interface module for it, you can increase the power to 5 kW + 5 kW = 10 kW per phase. Or you can make a three-phase system, but for now I’m content with that. The inverter is high-frequency, and therefore quite light (about 15 kg) and takes up little space - it can be easily mounted on the wall. It already has 2 MPPT controllers with a power of 2.5 kW each built-in, which means I can add as many more panels without purchasing additional equipment.

I have 2520 W solar panels according to the nameplate, but due to the non-optimal installation angle they produce less - the maximum I saw was 2400 W. The optimal angle is perpendicular to the sun, which in our latitudes is approximately 45 degrees to the horizon. My panels are installed at 30 degrees.

The battery assembly is 100A*h 48V, that is, 4.8 kW*h is stored, but it is extremely undesirable to take the energy completely, since then their resource is noticeably reduced. It is advisable to discharge such batteries no more than 50%. These lithium iron phosphate or lithium titanate ones can be charged and discharged deeply and with high currents, while lead-acid ones, be they liquid, gel or AGM, are better not to force. So, I have half the capacity, which is 2.4 kWh, that is, about 8 hours in fully autonomous mode without the sun. This is enough for the night of operation of all systems and there will still be half of the battery capacity left for emergency mode. In the morning the sun will already rise and begin to charge the battery, at the same time providing the house with energy. That is, the house can function autonomously in this mode if energy consumption is reduced and the weather is good. For complete autonomy, it would be possible to add more batteries and a generator. After all, in winter there is very little sun and you will not be able to do without a generator.

Gasoline modification

There are two designs of a self-made gasoline generator based on an engine from a trimmer and a generator from a car.

To assemble the first generator you will need:

• gasoline engine from a trimmer, preferably 4-stroke;
• working car generator;
• 12 V battery, not necessarily powerful, it will only be used for starting; Without it, the generator will not be able to generate electricity, since the collector will need to be supplied with an initial voltage for the first excitation.

The direct feed device is simple and straightforward. The only difficult stage is preparing the shaft for the drill chuck.

• First, the shaft is cut and sharpened on a machine, and then threaded to fit the chuck.
• Then the cartridge is screwed into which the shaft of the electric generator is clamped.
• Then everything is attached to a wooden stand.
• Now you need to start the gasoline engine and connect the generator to the battery. A voltmeter with a light bulb will check its operation.

The second method of assembling the generator is somewhat similar to the first, only a belt is used for the rotation process. A pulley is attached to the trimmer shaft, and everything is connected with a belt. Next, everything is attached to a wooden base. The trimmer is started and the operation of the device is checked.

As for the advantages of gasoline devices, there are many of them:

• The scope of use of the device is practically unlimited. It is used to supply power to a country house, summer cottage, or during emergency power outages in hospitals, pharmacies and retail outlets.
• The gasoline device is small in size and weight. Its small size ensures mobility: it is convenient to take with you and transport in the trunk.
• Low noise levels distinguish gasoline devices from diesel or gas ones.
• Gasoline generators are economical in terms of fuel consumption; it can be purchased at any gas station.

The disadvantages of this type of generators include:

• The main disadvantage is the high price. Gas and diesel are cheaper. Therefore, frequent use of such a device is not financially profitable.
• It has a low duration of continuous operation, which does not exceed 8 hours. But this time is enough to supply power or carry out work on the site.

I'm starting to collect

Before purchasing and assembling, it is necessary to calculate the entire system so as not to make a mistake with the location of all systems and cable routing. From the solar panels to the inverter I have about 25-30 meters and I laid two flexible wires with a cross-section of 6 sq. mm in advance, since they will transmit voltage up to 100V and a current of 25-30A. This cross-sectional margin was chosen to minimize losses on the wire and maximize energy delivery to the devices. I mounted the solar panels themselves on homemade guides made of aluminum corners and attached them with homemade fasteners. To prevent the panel from sliding down, a pair of 30mm bolts point upward on the aluminum corner opposite each panel, and they act as a kind of “hook” for the panels. After installation they are not visible, but they continue to bear the load.

The solar panels were assembled into three blocks of 3 panels each. In the blocks, the panels are connected in series - this way the voltage was raised to 115V without load and the current was reduced, which means you can choose wires of a smaller cross-section. The blocks are connected in parallel to each other using special connectors that ensure good contact and tightness of the connection - called MC4. I also used them to connect wires to the solar controller, as they provide reliable contact and quick closing/opening of the circuit for maintenance.

Next we move on to installation in the house. The batteries are pre-charged with a smart car charger to equalize the voltage and are connected in series to provide 48V. Next, they are connected to the inverter with a cable with a cross-section of 25 mm square. By the way, when you first connect the battery to the inverter, there will be a noticeable spark at the contacts. If you have not mixed up the polarity, then everything is fine - the inverter has fairly capacious capacitors installed and they begin to charge the moment they are connected to the batteries. The maximum power of the inverter is 5000 W, which means the current that can pass through the wire from the battery will be 100-110A. The selected cable is sufficient for safe operation. After connecting the battery, you can connect the external network and the load at home. Wires are attached to the terminal blocks: phase, neutral, ground. Everything here is simple and clear, but if it is unsafe for you to repair the outlet, then it is better to entrust the connection of this system to experienced electricians. Well, the last element is connecting the solar panels: here, too, you need to be careful and not mix up the polarity. With a power of 2.5 kW and incorrect connection, the solar controller will burn out instantly. What can I say: with such power, you can weld directly from solar panels, without a welding inverter. This will not improve the health of solar panels, but the power of the sun is really great. Since I additionally use MC4 connectors, it is simply impossible to reverse the polarity during the initial correct installation.

Everything is connected, one click of the switch and the inverter goes into setup mode: here you need to set the battery type, operating mode, charging currents, etc. There are quite clear instructions for this, and if you can cope with setting up the router, then setting up the inverter will not be very difficult either. You just need to know the battery parameters and configure them correctly so that they last as long as possible. After that, hmm... After that comes the fun part.

Vertical wind power generator

It is not difficult to make a wind device with a vertical axis of rotation with your own hands. It is enough to buy the required components, assemble them correctly and install the unit in the chosen location.

To make a wind device you will need the following materials:

• The axial mast is a supporting structure in the form of a pyramid, having a height of 5 meters. The generator and blades are attached to it.
• The blades catch the wind currents.
• The stator includes phases from coils.
• The rotor is the moving part of the windmill.
• The controller slows down the device when it develops more power.
• The inverter produces alternating current and the battery stores the energy.

To make the blades you will need high-quality plastic. Even plastic pipes will do. In this case, tin fragments are attached to each side of the pipe.

The rotor will require two ferrite disks with a diameter of 32 cm. For the stator, nine coils with 60 turns of copper should be made.

The mold for the coils should be made of plywood and lined with fiberglass.

You need to assemble a wind generator as follows:

• Make a hole in the top of the rotor for the pins.
• Make holes in the stator for fastening to the stand.
• Place the lower rotor disk on the stand with the magnets facing up.
• Here, install the stator and secure it to the plate with studs.
• Cover the structure with another disk.
• By rotating the pins, you should ensure that the upper and lower disks are evenly brought together, after which the pins and the plate are carefully removed.
• Secure the generator with nuts.
• Screw the finished device to the axial mast.

Electricity is started last: the energy from the device goes to the controller, is then collected on the battery and converted into alternating current by the inverter.

A vertical generator turns wind into an energy resource. To work well, it does not need additional devices that determine the direction of the wind.

Its maintenance does not require devices to ensure safe repair work.

Useful! The minimum number of moving parts makes this installation reliable and stable.

The device operates quietly, does not disturb neighbors and owners, does not produce harmful emissions into the atmosphere and reliably serves for many years.

Operation of a hybrid solar power plant

After the launch of the solar power plant, my family and I revised many of our habits. For example, if previously the washing machine or dishwasher started after 11 pm, when the night tariff in the power grid worked, now these energy-consuming jobs are moved to the day, because the washing machine consumes 500-2100 W during operation, the dishwasher consumes 400-2100 W. Why such a spread? Because pumps and motors consume little, but water heaters are extremely power-hungry. Ironing also turned out to be “more profitable” and more enjoyable during the day: the room is much lighter, and the energy of the sun completely covers the consumption of the iron. The screenshot shows a graph of energy production from a solar power plant. The morning peak is clearly visible, when the washing machine was working and consuming a lot of energy - this energy was generated by solar panels.

The first days I went up to the inverter several times to look at the production and consumption screen. Then I installed the utility on my home server, which displays the operating mode of the inverter and all parameters of the power grid in real time. For example, the screenshot shows that the house consumes more than 2 kW of energy (AC output active power item) and all this energy is borrowed from solar panels (PV1 input power item). That is, the inverter, operating in hybrid mode with priority power from the sun, completely covers the energy consumption of the devices from the sun. Isn't this happiness? Every day a new column of energy production appeared in the table and this could not but rejoice. And when the electricity was turned off in the entire village, I found out about it only from the squeak of the inverter, which notified me that it was working in autonomous mode. For the whole house, this meant only one thing: we live as before, while the neighbors fetch water with buckets.

But there are some nuances to having a solar power plant at home:

1. I started noticing that birds love solar panels and when they fly over them, they cannot help but be happy about the presence of technological equipment in the village. That is, sometimes solar panels still need to be washed to remove traces and dust. I think that if installed at 45 degrees, all traces would simply be washed away by rain. The output from several bird tracks does not drop at all, but if part of the panel is shaded, the drop in output becomes noticeable. I noticed this when the sun began to set and the shadow from the roof began to cover the panels one after another. That is, it is better to place the panels away from all structures that can shade them. But even in the evening, with diffused light, the panels produced several hundred watts.
2. With high power of solar panels and pumping of 700 Watts or more, the inverter turns on the fans more actively and they become audible if the door to the technical room is open. Here you either close the door or mount the inverter on the wall using damping pads. In principle, nothing unexpected: any electronics heats up during operation. You just need to take into account that the inverter should not be hung in a place where it can interfere with the sound of its operation.
3. The proprietary application can send alerts by email or SMS if any event occurs: turning on/off an external network, low battery, etc. But the application works on unsecured SMTP port 25, and all modern email services, like gmail.com or mail.ru, work on secure port 465. That is, now, in fact, email notifications do not arrive, but I would like to.

Not to say that these points are somehow upsetting, because one should always strive for perfection, but the existing energy independence is worth it.

Hydroelectric power plants for non-industrial purposes

Hydroelectric power plants are structures that can convert the energy of water movement into electricity. Alternative “green” electricity suppliers are so far only actively used in the West. In our country, this promising industry is only taking its first timid steps.

Small private hydroelectric power plants can be dams on large rivers, generating from ten to several hundred megawatts, or mini-hydroelectric power plants with a maximum power of 100 kW, which is quite enough for the needs of a private home. Let’s find out more about the latter.

Garland station with hydraulic screws

The structure consists of a chain of rotors attached to a flexible steel cable stretched across the river. The cable itself plays the role of a rotation shaft, one end of which is fixed on the support bearing, and the other activates the generator shaft.

Each hydraulic rotor of the “garland” is capable of generating about 2 kW of energy, however, the water flow speed for this must be at least 2.5 meters per second, and the depth of the reservoir should not exceed 1.5 m.

Garland stations were successfully used back in the middle of the last century, but the role of propellers was then played by homemade propellers and even tin cans. Today, manufacturers offer several types of rotors for various operating conditions.

They are equipped with blades of different sizes, made of sheet metal, and allow you to obtain maximum efficiency from the operation of the station.

But although this hydrogenerator is quite simple to manufacture, its operation requires a number of special conditions that are not always feasible in real life. Such structures block the river bed, and it is unlikely that your neighbors along the bank, not to mention representatives of environmental services, will allow you to use the energy of the stream for your purposes.

In addition, in winter, the installation can only be used on non-freezing reservoirs, and in harsh climates it can be preserved or dismantled. Therefore, garland stations are erected temporarily and mainly in deserted areas (for example, near summer pastures).

A modern analogue of a garland installation is submersible or floating frame stations with transverse rotors. Unlike their garland predecessor, these structures do not block the entire river, but use only part of the riverbed, and they can be installed on a pontoon/raft or even lowered to the bottom of the reservoir.

Vertical Daria rotor

The Darrieus rotor is a turbine device that was named after its inventor in 1931. The system consists of several aerodynamic blades fixed on radial beams and operates by differential pressure using the “lifting wing” principle, which is widely used in shipbuilding and aviation.

Although such installations are mostly used to create wind generators, they can also work with water. But in this case, precise calculations are needed to select the thickness and width of the blades in accordance with the strength of the water flow.

Vertical rotors are rarely used to create local hydroelectric power stations. Despite the good efficiency indicators and the apparent simplicity of the design, the equipment is quite complex to operate.

Before starting work, the system needs to be “spinned up”, but only the freezing of the reservoir can stop the running station. Therefore, the Darrieus rotor is used mainly in industrial enterprises.

An interesting solution in the field of designing small hydroelectric power plants with a vertically operating turbine was proposed by the Austrian inventor Franz Zotleterer:

A significant advantage of whirlpool stations is quite rightly considered to be the preservation of fish resources. The operation of a vertical turbine does not harm living organisms of the river. In addition, mud does not linger on the walls of structures due to the specific movement of water flow.

Underwater screw propeller

In fact, this is the simplest air windmill, only it is installed under water. The dimensions of the blades, in order to ensure maximum rotation speed and minimum resistance, are calculated depending on the force of the flow. For example, if the current speed does not exceed 2 m/sec, then the width of the blade should be within 2-3 cm.

Such a windmill is installed “towards” the flow, but its blades operate not due to the pressure of the water pressure, but due to the generation of lifting force (on the principle of an airplane wing or a ship’s propeller).

Water wheel with blades

A water wheel is one of the simplest versions of a hydraulic engine, known since the times of the Roman Empire. The efficiency of its operation largely depends on the type of source on which it is installed.

Depending on the depth and bed of the watercourse, different types of wheels can be installed:

But the principle of operation for all options is the same: water falls on the blades and drives a wheel, which causes the generator for the mini-power station to rotate.

Manufacturers of hydraulic equipment offer ready-made turbines, the blades of which are specially adapted to a certain speed of water flow. But home craftsmen make drum structures the old fashioned way - from scrap materials.

The following photo selection will help you get acquainted with the steps of constructing the simplest version of a mini hydroelectric power station:

Perhaps the lack of optimization will affect efficiency indicators, but the cost of homemade equipment will be several times cheaper than a purchased analogue. Therefore, a water wheel is the most popular option for organizing your own mini-hydroelectric power station.

Wind turbine protection from storms

We are talking about protecting the device from hurricanes and strong gusts of wind. In practice, this is implemented in two ways:

1. Limiting the speed of the wind wheel using an electromagnetic brake.
2. By moving the plane of rotation of the propeller away from the direct influence of the wind flow.

The first method is based on connecting a ballast electrical load to a wind generator. We have already talked about it in one of the previous articles.

The second method involves installing a folding tail, which allows you to direct the propeller towards the wind flow at nominal wind strength, and during a storm, on the contrary, to move the propeller out of the wind.

Protection by folding the tail occurs according to the following scheme.

1. In calm weather, the tail is positioned slightly at an angle (down and to the side).
2. At rated wind speed, the tail straightens and the propeller becomes parallel to the air flow.
3. When the wind speed exceeds the nominal value (for example, 10 m/s), the wind pressure on the propeller becomes greater than the force created by the weight of the tail. At this moment the tail begins to fold and the propeller moves out of the wind.
4. When the wind speed reaches critical values, the plane of rotation of the propeller becomes perpendicular to the wind flow.

When the wind weakens, the tail, under its own weight, returns to its original position and turns the propeller towards the wind. In order for the tail to return to its original position without additional springs, a rotating mechanism with an inclined pin (hinge) is used, which is installed on the tail rotation axis.

The tail rotation axis is set at an angle: 20° relative to the vertical axis and 45° relative to the horizontal axis.

In order for the mechanism to perform its main function, the axis of the mast must be at a certain distance from the axis of rotation of the turbine (optimally 10 cm).

To prevent the tail from folding and falling under the propeller during sharp gusts of wind, limiters must be welded on both sides of the mechanism.

An Excel table with ready-made formulas will help you calculate the tail dimensions and their dependence on other parameters of the wind turbine. In it, the area of ​​variable values ​​is indicated in yellow.

The optimal tail area is 15%...20% of the wind wheel area.

We present to your attention the most common option for mechanical protection of a wind generator. In one form or another, it is successfully used in practice by users of our portal.

WatchCat User FORUMHOUSE

During a storm, you need to slow down the propeller by moving it out of the wind. For example, when the wind is too strong, my windmill tips over with its propeller facing up. Not the best option, because returning to the working position is accompanied by a noticeable blow. But in ten years the windmill did not break down.

How much power does a family need?

On average, one family of three, taking into account a full set of equipment and an electric stove (and these are the ones most often found in houses, because running gas is even more difficult than running power lines) consumes 6-7 kW per day. And this is in an apartment. In the house, consumption will be even higher, because you need to additionally heat water, ensure the operation of the sewage system, and much more. Thus, we can conclude that a 5 kW solar power plant for a home will still not be able to provide everything needed. But if you cut down on your appetite and activate only what you need at the moment, you can get by with that amount. Ultimately, this is still significantly better than no power supply at all. The same refrigerator will be able to work around the clock, like other basic devices. But the TV, computer and other similar devices will have to be turned on only occasionally, which, in principle, is not as critical as it might seem.

Reviews

Judging by the reviews existing on the Internet, a fairly large number of people speak positively about the installation of such devices. Solar power plants for home, reviews of which can be found, are usually installed in remote parts and have no analogues in terms of convenience, comfort and cost. Yes, they really are still too expensive to fully replace centralized supply. But, firstly, this is only for now, and secondly, sooner or later such a power plant pays for itself and begins to save money. As was already said at the very beginning, cheap stations will help you gain profit within 5-10 years. Expensive and more powerful models rarely pay for themselves longer than 40 years. Some people have longer mortgages. One-time serious expenses will still be compensated, but you will have to pay for central electricity until the very last days of your life.

Sources used:

solarpanel.today, term.od.ua, energo.house, www.syl.ru, altenergiya.ru, sovets24.ru, www.asutpp.ru, m.habr.com, motocarrello.ru