Ugrás a tartalomhoz

Local resources and product path management

Ruszkai Csaba

Eszterházy Károly College Faculty of Natural Sciences

Solar energy utilization

Solar energy utilization

Sun is a gaseous, globular, about one and a half million kilometres diameter of radiation body, the outer surface of which closes to 6000 Kelvin temperature. The energy yield of sun radiation is given by a constant, which gives the magnitude of the medium distance of the Sun-Earth, which stands angles to the radiation, per unit of surface, per unit of time accessing solar energy.

Value: 1853 w / m2

The energy content of the (direct) radiation which reaches the limit of the atmosphere has been reducing significantly during its journey in the atmosphere: is has been partly absorbed, partly it faults, and partly it has been reflected by the particles of the atmosphere.

One part of the direct radiation transform to disordered direction, (diffusive) radiation

Clouds have the greatest impact on the intensity of the radiation which reaches the Earth’s surface. The maximum value of intensity in the summer eve, in bright weather, only rarely exceeds the 1000 W / m2 value. Divergent weather condition is associated with another and another magnitude of clouding, thus they result in different intensity.

  • In very cloudy weather: 50 − 300 W/m2

  • In slightly cloudy, avarage weather 500 − 600 W/m2

  • In brighty, summer weather:: 900 − 1000 W/m2

Even so, currently there are hardly any use of this energy source, though, undoubtedly, a number of favourable factors pros to its application.

  • It is easy to reach for everyone,

  • It is a pure, eco-friendly energy source,

  • It will be disposable even for many million years,

  • It spares stock of raw material

  • It has positive effects on local economy,

  • It does not require delivery, system of public utilities is not necessary to obtain wind energy

  • Its transformational and reclamations costs are minimal

Solar collectors and solar panels are able to utilize solar energy for an effective way for us. (active solar energy utilization) In an indirect way, heat pumps are also able to exploit solar energy. The soil, the underground water, the air also conveys oar energy which may be exploited by heat pumps, too.

There are two types of solar energy exertion: Active and passive solar energy exploitation. Solar panel belongs to the actives, which generates electric power, and the solar collector with which warm water is produced. Passive energy utilization manifests itself in architecture., in the course of which it is possible to use solar energy for heating the buildings without a special additional device, such as with appropriate orientation, glazing, efficient heat insulation. Solar energy is utilized during the construction of active and passive houses which highly complies with contemporary environment protection ordinances

Figure 17. . Premiere passive house in Kassel (own Figure)

The essence of the operation of solar panels is that they directly transform incoming energy to electric power, the storage of which is solvable in accumulators. The resulting power may be used for operating electric gadgets, such as electric boilers, oven, televisions, computers or even for electric car charging. Green ride may be reached with the latest, which is one of the types of eco-friendly transport. If the produced power amount is not used, we may sell it to a power – company through inverters.

Solar collector

Three times more energy may be gained from the surface of solar collector what has the same size than a solar panel. The result of their operation is that they are able to heat warm water with incoming energy, wherewith family houses, panel building or offices can be heated. Storage of warm water may happen in containers. The achievable temperature is about 40°C.

One person normally use 50—60 litre water per day, to a production of which, about 2-3 KWH heat energy is necessary. In the summer averagely about 2, 2,5 kWH/day heat power may be generated with 1 m2solar collector.