Solar energy
Our daily energy needs are covered almost exclusively from conventional energy sources, such as petrol, gasoline and coal. The electricity we use derives from these sources, which, despite their great contribution to our modern culture, pollute the environment beyond remedy and are rapidly diminishing. On the other hand, Renewable Energy Sources can be replenished through natural cycles and are considered practically inexhaustible. Greece provides considerable RES use capabilities, through the sun and wind, sources which never run out and their use does not pollute the environment.

Solar energy is a clean, inexhaustible, mild renewable energy source. Solar radiation cannot be controlled by anyone and constitutes an inexhaustible energy source, which provides independence, predictability and security of energy supplies. One way to use solar energy is through photovoltaic elements. Photovoltaic elements produce electricity when the photons of the solar light are absorbed by the photovoltaics and knock electrons into a higher state of energy. There are three types of photovoltaic elements, the so-called monocrystalline, polycrystalline and amorphous silicon solar cells which are low-efficiency and low-cost. However, they all share the following advantages:
• zero pollution
• silent function
• reliability and long life duration (may reach 30 years)
• independence from fuel supplies for remote regions
• expansion potential depending on needs
• minimal maintenance

A photovoltaic installation may constitute an independent system which covers the overall energy needs of a household, without a connection to the DEH grid. For constant consumer service, the installation must also include a storage unit (battery) and energy management unit. Alternatively, a photovoltaic electricity production system may be used together with the DEH grid. In this case, electricity is consumed from the grid when the photovoltaic system is insufficient, and energy is supplied (at a much higher sale price than the market price due to the grant) to the grid, when the production exceeds the needs of the household. Photovoltaics produce constant electricity. This means that they are used with direct current appliances or we convert this direct current into a 230V alternating current (i.e. the same current as that used by the DEH grid) with the help of some electronical devices. Lighting, telecommunications, cooling, audio coverage and any other energy need can be covered by a specially designed photovoltaic system.