Student, Assem Atchabarova, research supervisor, Ph.D., Vladimir Sapa

Kostanay State University A. Baitursynov, Kazakhstan

Photovoltaic plants in agriculture

In agriculture, there are great opportunities for the application of solar installations - in crops, livestock, and horticulture. The result of applying - solar greenhouse; dryers; hot water and heating captive breeding of cattle, pigs, poultry; heating water in pools for fish farming.

For example, consider a modern cattle-breeding complex for 500 head of dairy cattle. Need a farm with a milking parlor - 40 kW • h batteries installed in the summer will help cover the needs of the farm (Fig. 1). Excess energy can be given to the electrical network.

Photovoltaic plant consists of 280 polycrystalline modules with capacity 245-250 W tolerant capability (-0 / + 5W). They are installed on the roof of the building. Installed capacity of 70 kW. 280 solar panels and three inverters convert elaborated battery DC to AC. In winter, this plant produces 10 ... 20 kW, the rest of the energy is taken from the network.

The cost of a solar panel in an average of 100 thousand tenge. For our farm costs for solar panels will make about 28000000 million tenge. With the average cost of electricity for farmers 18 tenge per kW ∙ h. Station should be recouped in about 7...8 years. Such station will work much more payback period (not less than 25 years). In this case, the cost of electricity will be about half the price. Introduction of new technologies - the basis of successful business.

When calculating for each region to be analyzed statistics solar activity for some years. On the basis of these data must be averaged to determine the actual power of the solar flux per square meter of the earth's surface. These data can be obtained from local or international meteorological services. Statistical data allow to predict the minimum error of the solar energy system, which will be converted into electricity by solar panels.

Fig. 1. The use of solar panels to agriculture

The main advantage of solar panels - they are extremely constructive simplicity and the absence of moving parts. As well as a small specific gravity and simplicity combined with high reliability. As simple installation and minimal maintenance requirements during operation. Representing a flat elements of small thickness, they are quite successfully placed on the converts to the sun roof slope or on the wall. Do not require additional space and the construction of separate bulky designs. The only condition - nothing should obscure them as much as possible during the time.

The efficiency of photovoltaic cells falls within the lifetime. Wafers eventually degrade and lose their properties. The efficiency of solar cells is even less. Prolonged exposure to high temperatures accelerates this process. For 25 years the efficiency of the solar cell is reduced by only 10%. The normal life span for today's solar cells is at least 25 ... 30 years.

When choosing solar photovoltaics should pay attention to the dependence of the voltage produced by illumination - it should be as small as possible.

The disadvantages of photovoltaic plants include sensitivity to contamination. Even unobtrusive layer of dirt on the surface of the photocells or safety glass can absorb a significant share of sunlight and saves energy. In the dusty town that would require frequent cleaning of the surface of solar cells, especially installed horizontally or with a slight slope. The same procedure is necessary after every snowfall, and after the dust storm.

Taking into account the long life and the opportunity to work for a long time without any maintenance, photovoltaics for his life may well pay off more than once, and not only in remote areas.

References:

1. Yurchenko, A.V.; Savrasov F.W.; Yurchenko V. The real cost of energy - from resources to consumer // Bulletin of the Tomsk Polytechnic University. - 2009. - P. 43-46.

2. Stepanenko, N.I.; Gubin, V.E. Prospects for the use of alternative and renewable-energy sources in the conditions of Siberia // Modern Techniques and Technologies: Proceedings of IX Intern. Conf. students, graduate students and young scientists. - Tomsk, 2003. - T. 1. - P. 47-48.

3. Lukutin, B.V.; Surzhikova O.A.; Shandarova, E.B. Renewable energy in decentralized energy supply. - M .: Energoizdat, 2008. - 231 p.