Solar Panels
Solar pump in Bangladesh
Solar pump is one of the important inventions for irrigation system.
The power generated by solar energy is use for water pump,
which is useful for irrigation purpose. Using local technology
the renewable energy resource center of Dhaka University
invented solar pump. This solar pump can be used for
irrigation purpose.6th September 2009 a news briefing
about this invention was given by the resource center.
Bangladesh is an agricultural country here irrigation
is most important for cultivation. But only 35 % cultivable
land under irrigation, 65% is not perfectly irrigate.
The invention of this solar pump will perform important
role for irrigation system. To make this solar pump local
inverter was used. So price is less than the general pump.
If the farmer buys this pump they will able to use at
least 25-30 years. Now time comes for Bangladeshi
engineers to concentrate their mind how can make our
country free from load sheading. For this purpose solar
energy can play important role.
Solar energy
Solar energy is one kind of energy in which solar radiation is used for production of energy. Among the various non-conventional source of energy solar energy seems to hold out the greatest promise the mankind. The solar energy is free, inexhaustible, nonpolluting and friendly for environment. The rapid depletion of fossil fuels and combined crisis of pollution and of steep rise in oil price have brought about an upsurge of interest in Solar energy. The existing source of energy such as coal, oil, water and uranium may not be sufficient to meet the increasing energy demands. This requires that scientists and engineers should undertake resources work which would help in exploring the possibilities of harnessing energy from several nonconventional source of energy.
Application field of solar energy
But energy production rate is small so most applicable field are
to operate irrigation pump, navigational signals, high way lighting,
rail road crossing signal and so many little consumption devices.
It also use to power supply for microwave repeater station , radio
and television receiver,solar water heater, solar refrigeration etc.
Flate plate collector
Flate plate collector is made in rectangular panel are relatively simple to construct and erect. Flate plate collect and absorb both direct and scattered solar radiation, that effective even cloudy days where there is no direct radiation.At first solar ray pass into transparent cover and fall on absorbing surface. this absorbing surface is usually made of copper aluminium. By flat plate collector it is not possible to generate steam , so this system can not be used directly to run steam generating unit.
insulation is used to prevent loss of heat from the absorber and heat transforming fluid. This insulating materials commonly used are fibreglass or styrofoam
Solare energy collector
Solar collectors transform solar radiation into heat and transfer that heat to a medium (water, solar fluid, or air). Then solar heat can be used for heating water, to back up heating systems or for heating swimming pools.
There are various ways that can be exploited solar energy
a. Direct conversion to fuel by photosynthesis
b. Direct conversion to electricity by photovoltic cell
c. By conversion to electricity via thermo electric power system
Solar Cell
Solar cell or Photo voltaic cell (PVC) is device which directly convert solar energy to D.C power.
This cell made of semiconductor that generate electricity when it absorb light. Gallium arsenide is the another solar cell material.Solar cell made of gallium ,arsenide can retain efficiency at much higher temperature,than cell made of silicon.The best known application of photo voltaic cell for electrical power generation. In space craft silicon solar is the most highly developed type.
Various Advantages of solar cell are:
a. Need little maintenance.
b. life is longer.
c. Do not cause environmental pollution.
d.Easy to fabricate.
e. Energy source for solar cell is unlimited.
Disadvantages are:
a.Cost of production of electrical power very high compare to other.
b. Output electrical power varies with the time and weather , generally power produce in day.
c. Solar cell produce small amount of power compare to the other.