How to install and operate solar panels

When choosing a solar power plant and analyzing the options for operating solar modules, it is important to decide on the potential for obtaining solar energy.

Scientific calculation methods

The science of "Insolation" (formed from the term "in solis") is engaged in accounting for the irradiation of the Earth's surfaces by the rays of the Sun.

It takes into account the direction of a parallel beam of light rays from the center of the solar disk by geometric and energy methods, which allow to reveal for the light flux:

• direction;

• cross-sectional area;

• dependence on time and season;

• density;

• exposure in light units.

The effect of solar radiation on the Earth

Solar array location affects the quality of reception of the light flux, is determined by the angle of inclination of its surface relative to the axis of the light rays. In practice, it can be oriented in different ways, but three characteristic options are chosen for calculations:

• horizon plane of the earth's surface;

• optimal angle;

• perpendicular to the axis of the light flux.

The first method involves placing the modules parallel to the plane of the water mirror of the area.

Orientation at an optimum angle consists in stationary fixing of the solar battery in an averaged, most favorable position for receiving solar energy. This method is influenced by the angle of latitude and the inclination of the axis of rotation of the Earth.

The third option is to organize a system for tracking the position of the Sun in the sky and automatically maintain the direction of the plane of the solar modules perpendicular to it.

Brief conclusions

For the conditions of Russia, insolation methods have revealed the average statistical possibilities for obtaining solar energy in kW / h from 1 m² area for one calendar year. They are tabulated.

For information. In practice, technical methods are implemented that allow you to get more energy from one square meter of the solar module, based on the collection of light flux from neighboring areas.

For this purpose, the following are used:

• scheme of rotatable flat mirrors that reflect light on a solar battery;

• rotary mirror of linear hyperbolic shape with the possibility of rotation only around one axis.

Both methods are effective, but require serious technical calculations, complex mechanics and large financial investments. However, they make it possible to understand that it is possible to increase the efficiency of a home solar station by simple methods of additionally directing reflected light from neighboring walls, building structures, and screens. To do this, it is enough to color them in bright colors, reflecting light waves.

Why take insolation recommendations into account

In the article "How solar panels are arranged and work" data on the operation of photovoltaic converters are provided and their rather low efficiency is noted. Manufacturers of such equipment are constantly looking for ways to increase it, conduct extensive scientific research, change production conditions, but ... revolutionary technologies are not yet in sight.

Solar modules are expensive, they convert a small fraction of the energy received into electricity. Therefore, it is important to use all factors with maximum benefit.

Mounting method

For mounting solar panels, a frame with profile aluminum or steel frames is manufactured. You can use a tree, but it, no matter how you protect it, is subject to drying out, decay, is not so durable.Fastening the battery to the frame is carried out by ordinary locker screws or screw connections in the most convenient place.

Orientation

Human vision adapts to the perception of the world in such a way that we are comfortable. Our eyes adapt to the light stream, smoothing it. Artists and photographers using lighting effects take these features of vision into account in their work.

Correctly assessing "by eye" the method of orientation of the solar battery in space is very problematic. This should be done using instruments, and take into account that the Sun irradiates our northern hemisphere as much as possible from the southern direction. Of course, light energy comes from the east and west, but with great losses.

Therefore, the plane of the solar battery should be positioned perpendicular to the southern direction at an angle to the horizon plane, which can: be installed once for year-round operation; change according to the seasons.

For stationary fixation, the optimum average value coincides with the parallel (latitude). For example, for the Leningrad region, 60 degrees are set.

The control method is more effective even when manually reinstalling the angle twice a year (data for the same area):

• in spring - up to 45^about;

• in the fall - up to 75^about

Using a tracking system in a home solar power station is disadvantageous:

• high windage with strong gusts of wind can lead to the breakdown of an unreliable structure;

• the cost of the system is comparable to the price of three solar panels;

• the expected economic effect will not exceed 40%.

Therefore, instead of a tracking system, it is better to purchase an additional solar module.

The effect of temperature and snow

The photoelectric converter reacts negatively to an increase in temperature: it reduces the output power. And solar modules, exposed to the sun, heat up. They, fixed tightly on dark surfaces, for example, black roofing material, can work in the "pan" with a temperature of more than +80^aboutFROM.

Therefore, when mounting on any building structures, it is necessary to provide free space on all sides of the photoelectric converter for natural air circulation and heat dissipation. This is especially true for flat surfaces: concrete slabs, tin sheets. Waves of slate, ondulin provide air approach, but in winter they are covered with snow.

It is convenient to mount solar panels on a flat roof with orientation to the south or in the open sun. For this, a frame in the form of a triangular horizontal prism, raised above the base surface to a height exceeding possible snow drifts, is welded from metal corners. This is the so-called passive protection against snow blown space. But in it it is necessary to reduce the number of stops from below or increase the distance between them.

The created frame is reliably bolted to the power elements of the building structure, and solar modules are installed in it.

In some cases, good thermal conditions can be created by lowering the frame mount below the ramp at the roof. This is one of the effective methods for creating good air exchange.

The rectangular shape of the solar panel is extended in one direction. With vertical orientation, the temperature difference between the cells of the upper and lower sides increases, which is undesirable. Choose a horizontal arrangement.

Being engaged in free access of air, do not forget about rigidity and durability of all design.

Any way to reduce the operating temperature of the photoelectric converter even by one degree during the year gives a noticeable increase in power.

Reflected light

The solar battery receives light from all sides, including the back surface (with reflected light).Experiments in a snowy field showed that due to the conversion of reflected light by the back of the solar battery, it is possible to obtain an increase in power from it up to 30-50% and, in some cases, exceed the declared characteristics of the manufacturer.

What prevents installing solar modules in unshaded places, directing additional light from them from light neighboring building structures, and painting objects located on the back side with retroreflective paints?

Season effect

The effect of solar radiation on seasons on Earth

The worst working conditions home solar power station are created in the fall:

• daylight hours are reduced;

• cloudy weather and clouds sharply reduce solar flow;

• the dark surface of the earth absorbs and does not reflect light.

The picture changes after the first snow - the diffuse lighting by the snow cover increases.

However, densely standing buildings and trees, especially coniferous forests do not reflect light. In this situation, it is possible to capture the light flux scattered from the clouds and the sky, but you will need to experiment with the angle of the photoelectric converter.

An open snow field is capable of creating more than 85% of the reflected light. This method should be given attention.

Seasonal differences in insolation can vary within wide limits (up to 6 times). Therefore, the spring day and dark autumn evening, the possibilities of a home solar station are very different.

Considering the cost of a solar battery, it is recommended that at the end of winter or early spring buy their minimum quantity in order to gain operational experience and check the quality of production. At the end of autumn, you can buy the rest for autumn-winter operation. In addition, discounts and promotions apply during this period.

Remember your feelings when you go out on a sunny February day:

• the sun blinds your eyes (remembered about dark glasses);

• frost pinch on the cheeks;

• light reflects off snow;

• daylight is growing.

These are ideal conditions for the operation of the photovoltaic converter. It produces increased power and there is no need to particularly worry about its cooling, as in the summer.

If you made a mistake in the calculations and solar panels successfully cope with the tasks: even there is a reserve of power, then maybe ... you don’t need to buy them in the fall? Or purchase less? Why not check in this way?