Solar Energy

Solar energy - the use of solar radiation to produce energy in any form. Solar power uses a renewable energy source and in the future may be clean, that is not generating hazardous wastes.

Today, solar energy is widely used in cases where the inaccessibility of other energy sources, coupled with an abundance of solar radiation justify its cost.

The advantages of solar energy:.

a. Accessibility and inexhaustible source of.

2. Theoretically, the complete safety of the environment ( but currently in the production of solar cells and in themselves contain hazardous substances). It is likely that the widespread implementation of solar energy can change the albedo of the earth's surface and lead to climate change (but at the present level of energy consumption is extremely unlikely).

Disadvantages of solar energy:.

a. The fundamental problem.

Because of the relatively small value for the solar constant, solar energy requires the use of large areas of land for power plants (for example, 1-GW power plants it may be several tens of square kilometers). However, this disadvantage is not so great, such as hydro outputs from the use of much larger tracts of land. In addition, the photovoltaic cells on the large solar power plants are installed at a height of 1.8-2.5 meters, which allows the use of land for the power plant for agricultural purposes, such as grazing.

The problem of finding large areas of land for solar power is solved in the case of solar power balloon, suitable for both terrestrial and maritime and high-rise home for the.

The flow of solar energy on Earth's surface depends strongly on latitude and climate. In various places the average number of sunny days per year can vary greatly.

2. Technical problems.

Solar power does not work at night and not effectively work in the morning and evening twilight. The peak power consumption falls on the evening. In addition, power plants can fluctuate dramatically and unexpectedly due to weather changes. To overcome these shortcomings need or use efficient electric accumulators ( today it is an unsolved problem ), or to build a pumped storage station, which also occupy a large area, or use the concept of hydrogen energy, which also is far from cost-effectiveness.

The problem of dependence of the power of solar power on time of day and weather conditions is solved in the case of solar balloon power.

The high cost of solar cells. Probably, the development of technology will overcome this disadvantage.

Lack of efficiency of solar cells (probably soon to be increased).

The surface of the graphic panels should be cleaned of dust and other contaminants. With their area of ​​several square kilometers of it may be difficult.

The efficiency of photovoltaic cells decreases markedly when they are heated, so there is a need to install cooling systems, water is usually.

After 30 years of operation efficiency of photovoltaic cells begins to decline.

3. environmental issues.

Despite the ecological purity of the received energy, photovoltaic cells themselves contain toxic substances such as lead, cadmium, gallium, arsenic, etc. Dr.. , And their production consumes a lot of other dangerous substances. Modern solar cells have a limited life (30-50 years), and the massive use of supply in the near future the same time a difficult question of their disposal, which also does not yet acceptable from an environmental point of view of the.

Because of environmental problems and deficits arising silicon begins to actively develop the production of thin-film solar cells, which include those containing only about 1 % of silicon. In addition, thin-film solar cells are cheaper to produce, but there are less effective. For example, in 2005. company. «Shell». decided to concentrate on the production of thin-film elements, and sold his business for the production of silicon photovoltaic cells.

according to the materials. Wikipedia. py.