A.H. Tleuov D.Sc.,  I.A. Pyastolova Ph.D., A.A. Tleuova Ph.D.

S.Seifullin Kazakh Agro Technical University, Kazakhstan

The use of solar power plants in Kazakhstan

These days, people provide themselves with energy mainly traditional-governmental ways: build thermal power plants operating by the burning of natural resources (gas, coal and oil), erect hydro cascades, using the power of rushing rivers, and nuclear power plants, which extract the energy of atomic nuclei. The three main components of energy, which is called the "lifeblood" of civilization, on the one hand, provide a high standard of living, on the other - have caused enormous damage to the environment.

Everyone knows that the natural resources are being depleted. But it's not close, as recently thought of exhaustion (coal reserves, for example, will last for many hundreds of years) - concerned primarily detrimental effect of using non-renewable energy resources in the human environment. The main drawback of combustion in thermal power plants (TPP) of fossil fuels - Environmental pollution by harmful emissions. Even TPP working with the use of modern high-efficiency technologies, such as coal combustion in a fluidized or circulating fluidized bed, from an environmental point of view, is far from perfect. In addition, the cause irreparable damage to the production, processing, transportation fuel, and a useless gas flaring and oil. We must not forget that in addition to the natural raw material to the power station burns atmospheric oxygen, planetary reserves are not unlimited, too.

Requirements for development and the development of energy from renewable resources is becoming increasingly important with the increasing demand for fuel, oil in particular, the growth of population and the requirements of the standard of living and changes in environmental conditions on Earth.

This increase energy production is difficult to ensure without the use of new energy sources have been increasing needs for energy fuel reserves are being depleted. Regardless of their attitude to nuclear power energy programs of all countries contain, as a rule, the two main points to improve energy supply:

§ development of energy from renewable energy sources;

§ improved utilization of produced and consumed energy.

Renewable sources of energy - it is based on sources constantly existing or recurring environmental energy flows. A typical example - the solar radiation with a characteristic repetition period of 24 hours

The main determining factor for determining the performance of solar systems is the flux density of the total solar radiation in the plane of the collector.

To predict the thermal performance solar plants need, from our point of view, to consider the mutual influence on each other the following conditions:

- Temporal and latitudinal distribution of the total incoming solar radiation;

- The impact of solar activity on the amount of solar radiation on the surface of the Earth.

The duration of sunshine, as well as the duration or length of the day, are important characteristics to determine the duration and timing of the operation of solar heating and hot water.

The most common characteristics of sunshine duration are the possible duration of the absence of clouds, the actual duration of the subject of clouds, the ratio of the actual duration of sunshine to the possible and the number of days without sun.

Possible daily sunshine duration is the most stable and reliable characteristics. It is determined by the time of sunrise and sunset view of its refraction, i.e. is purely astronomical figure.

As a result of the S.Seifullin Kazakh Agro Technical University studies for the day duration in Republic of Kazakhstan between sunrise and sunset is from 7 in January and up to 17 hours in June.

The distribution of sunshine duration at an average conditions of clouds in the Northern region of Kazakhstan from 80 to 320 hours in January. In the year - 2000-2200 hours.

The distribution of the average monthly number of days without the sun is 8 to 1, and the annual number - 55 - 70.

All of this suggests the prospects of using solar systems not only in the South but also in the north of the Republic of Kazakhstan.

Serious consideration should be given to the installation of solar hot water systems, as they are easy to build and use a private farming.

Solar heating has developed in many foreign countries. Most units are equipped with solar heating solar collector. Only in the U.S. are operated solar collector area of 10 million square meters, which provides annual savings of up to 1.5 million. The use of solar energy today is reduced mainly to the production of low-grade heat using simple flat-plate solar collectors, which is used for hot water, heating water in swimming pools and, to a lesser extent, for heating systems.

In Israel passed a law that requires every home was equipped with a water heater. Therefore, there is set around 800 thousand solar collectors that produce approximately 15 million GJ of energy and provide 70% of the hot water.

In new homes are attempts to connect collectors with elements of house roof, making it easier and cheaper to install. Complete water heater includes besides collectors insulated storage tank (which is embedded in the backup electric heater) required valves and automation. The collector is usually set fixed angle to the horizontal approximately equal to the latitude areas. On the single-family house with an area of about 100 square meters of collector is usually set 1-2, with an area of absorber 1-1.5 square meters each and the storage tank capacity of 150 liters. Such a plant in the western market today is about 500 per square meter of collector area. Heating capacity of such a facility depends significantly on the insolation, ambient temperature and other climatic parameters. Depending on latitude and climate annual influx of solar energy on 1 square meter of surface changes very much. For latitudes 40-55 ° it is up to 6.4 GJ/(m²year). The cost of the heat produced by such facilities for long service life makes these plants attractive to consumers. In any case, in terms of Kazakhstan solar water heaters can be used as seasonal, according to our calculations, this is 6-8 months in a year.

The average annual value of the total solar radiation at latitude 50^o, which stands for the day of 20 square meters, level surface is 50 ... 60 kWh. This corresponds to the energy cost of heating homes of 60 square meters.

The most important task should be considered as the development of methodology for assessing the contribution of the solar system in the energy balance of the house. The final percentage of solar energy is usually expressed as a percentage. In projects of solar homes with a combination of passive and active systems proportion of solar radiation in meeting the energy needs of homes ranges from 80% (in areas with the highest levels of solar radiation) to 40% (in northern areas).This makes it possible to determine at least roughly the effectiveness of the solar system. 

These calculations are based not immediate, today's economy, and cost analysis for the lifetime of the system, which is approximately 20 years. A comparison of the cost of operation of conventional and solar homes during this period shows that, although the use of the solar system gives an increase in the capital cost of construction by 10%, this increase is offset by a decrease of 60% in heating costs. The ultimate savings in this case was 18%. According to the publication ASES, the cost of conventional fuels by using solar systems can be reduced by 50-70% with an increase in capital expenditures for the construction of only 3%. However, the main achievement should be considered after all the social and ecological impact. 

Over the past 15-20 years, "solar" house began to grow like mushrooms after rain. In the simplest and most common form most of the energy needs of the house is provided by solar light and heat, thereby decreasing the cost of other energy by 40-60% (depending on the design of the building and its location). A "solar" home, equipped with efficient thermal plant, can fully meet the needs of its residents in the warmth and light even without the use of other energy sources. And yet - no blackouts and power outages, no wires from the outside, no counters, no stockpiles of wood, coal or fuel oil. 

The main thing in the concept of "solar" dwelling house - the maximum, based on the terrain and climate, the use of solar radiation, converting it into heat and store thermal energy in the house with minimal losses. The implementation of this approach provides significant cost savings and improve environmental conditions (due to the minimal use of all other energy sources) in the atmosphere is less than the combustion products, the roads are exempt from heavy vehicles carrying millions of tons of fuel wood saved from being cut down for firewood and so on.