Electricity generation

The easiest way to convert solar energy into electrical energy is to use solar batteries. Solar battery/element is a device which converts the energy emitted by the sun (light) directly into electrical energy. The conversion of solar energy into electricity is enabled by photovoltaic process within the solar battery, otherwise known as the photovoltaic effect. This process proceeds at the time of junction between different structures of electrical semiconductors when photovoltaic device, i.e. battery, is under the influence of sunlight. During photovoltaic process the electrical semiconductor carries out the role of energy receiver. The light incident upon solar battery induces the semiconductor and the electric field undergoes charge separation resulting electrical energy supply. In order to obtain larger amounts of electrical energy, solar batteries / cells are connected into systems, called solar modules. The compounds of solar modules, in turn, comprise an entire photovoltaic system. The electricity generated by the system of solar modules can be supplied directly to the public power network or stored in accumulator batteries to ensure that electricity will be supplied during the night or when the intensity of sunlight is insufficient during the rainy or overcast day.

AC - alternating current. DC - direct current.

Solar modules - the most important part of the system, which converts solar energy into electrical energy. In the production of photovoltaic inverters there can be used monocrystal (m-Si), polycrystal (p-Si) and amorphous silicon (a-Si) and other semiconductor materials: gallium arsenide (GaAs), indium phosphate (InP), cadmium telluride (CdTe), copper indium diselenide (international acronym CIS), copper indium gallium selenide (CIGS international abbreviation), indium gallium nitride (InGaN), and others. Currently, sillicon (>90%) is generally used in the production of photovoltaic inverters because other suitable semiconductor materials are much more expensive.

PV module is such photo electronic inverter which is designed so that its overall dimensions and electrical parameters (output, voltage) meet certain contractual terms. In addition, it must be protected from the atmospheric impact (covered with glass or other transparent refractory coating, sealed), easy to install and maintain. Monocrystal and polycrystal silicon photovoltaic modules are made up of a number of low power (typically 0.5 to 4 watts) small photo electric cells, which, while combining series connection and parallel connection, are connected in such a way that you get proper conventional electrical module parameters. Monocrystal solar cell-based battery is almost twice as efficient as compared with amorphous silicon (thin-film) batteries: the same power production using monocrystal solar panels will double the space of less than thin film modules;

Amorphous silicon modules (thin film) are produced by covering metal substrate with thin silicon layer. These modules are not composed of a single low-power processing elements (cells), but they have one large and thin solid photoelectric surface, consuming the entire module area. The power of modern photoelectronic modules ranges from a few watts to 300 W. If you need to get more power through the combination of parallel and series connections, the modules are connected into larger modules. These modules can be used as a wall or roof surface or for semi-transparent balcony, attic, stairwell glazing. Thin film modules are designed to reduce the rising current, increasing the tension generated by transfer of almost 3 times less current than polycrystal modules. This is especially true in the construction of many low-power solar arrays. In addition, thin-film solar battery losses due to high temperature are almost twice lower than other solar cells. The solar battery system based on thin film technology generates about 20% more power in the diffused sunlight conditions (i.e. cloudy days or rain). Currently, polycrystal and monocrystal modules cost is almost equal. Thin film modules are more than 20% cheaper.

(In order to compare the technologies of solar elements, the table provides the same power (Wp), different production technologies and solar technical parameters)