Barmer district is situated at the 71° 23' East Longitude and 25° 45' North Latitude in west of state Rajasthan and country India. Total area is 28387 km2. Even 1% of this area can produce 24GWh electrical energy per year. The average sun shines for 340 days a year. The Sun gives light energy @ 1KW per square meter at 25 ° cell (solar cell) temperature and 1.5 air mas The solar insolation is 2400KWh per year. This means that if we install 1KW solar power plant at home, we can get energy of 2400KWh per year. This amount of energy is sufficient for average house hold. Besides this small power plant we can construct big plants in the range of 1MW to 500MW or more. These big plants can be grid connected for further supply to destinations. Though the energy cost of generated electricity is Rs.15/- per KWh, but it is pollution free energy. 1KW solar plant saves 0.8tones carbon. The solar energy is not only environmental friendly, but it also generates employments. The land owners can be made partner for that power plant.The secret of solar power plant is that it can be constructed in 1KW, 2Kw, -----1MW, 10MW ,100MW and so on
There are two types of solar plants.
1. Photovoltaic Stand alone system
2. Electric grid connected system.
Stand alone system is independent system which generates electrical energy from photovoltaic cells. This can be installed on home's roof to fulfill the requirement of home owner. It consist of solar panels, deep cycle batteries for power back up, inverters, charge controllers & power panel etc. The part of system other than solar panel is called B.O.S(Balance of system).The grid connected system is the same as stand alone system but it has no back-up batteries, the electricity is generated and sent to electric grid. One can use also back flow meter to sell the excess amount of energy at day time and receive back when there is no sun, in night or cloudy season. Commercially grid connected systems are of two types. 1. Photovoltaic 2. Solar thermal. The photovoltaic is described as above, but the solar thermal power plant is different one. It uses parabolic concentrated glasses, a liquid passes through it and heated to 600°centigrade, this temperature produces super heated steam and power is generated from steam turbines just like fossil power plants. .
1. Photovoltaic solar cell stand alone system:- 1KW
It is useful small houses for lighting purposes, water pump sets. It can be installed on the roof of house or ground. It consists of :- .
1 Solar panels made of mono crystalline or poly crystalline silicon cells 1000Watt.
2 Deep cycle battery 500AH
3 Combiner box
4 Charge controller
7 Utility circuits A.C and D.C
Site selection:- The solar panel should be mounted at shade free areas. Atleast the sun should remain during 3.0 hours before and 3.00hours after solar noon. The roof area should be 200 Square feet (Approx. 20.M2).The roof should bear wind load and panel weight. If you are installing solar panels on the ground, than these should be protected with fencing.
Solar panels mounting:- Solar panels are mounted on iron fixtures so that it can withstand wind and weight of panels. The direction of panel is south facing for maximum power tracking. The tilt angle of panels will be 25° from horizontal. This angle is called axis tracking angle. You can set 40° degree tracking angle in the month of December and 10° degree in the month of June. In the month of September & March it will be 25° degree.
Determination of south:- For correct mounting of panels you should determine the true south. Erect a 5 to 6 feet wooden stick vertically on the ground and see the shadow of this stick at the mid day time. ( watch the time of sun rise & sun set of any day and get total sun day, make it half and add to sun rise. This time is called solar noon.). The shade indicates true south and true north. You need not to find magnetic compass. Because for Barmer true north and magnetic north are approximately equal.
Deep cycle batteries:- Do not use automobile batteries. These batteries are different from ordinary automobile batteries. These batteries can be discharged up to 80% as compare to automotive batteries, which can be discharged up to 20%. Batteries are connected series and parallel in such a way to produce 48 Volts. 500Ah battery is sufficient.
Combiner box:- Solar panels are connected parallel or series to produce 48 nominal volts.
Charge controller:- Maximum power tracking charge controller should be used. Solar power increases from sunrise and become maximum at noon and decreases to sun set. So charge controller regulates the power output.
Inverter:- It converts D.C to A.C. 48Volts D.C is converted into 230Volt A.C at frequency 50 cycles/second. Do not use U.S.A standard inverter because it uses 60c/s.
Grounding:- Solar panels should be grounded properly to save from lightening.
Utility- A.C & D.C circuits: We can use both utility electric circuits for our basic needs.
Water pumps:- Batteries and inverter is not used in this system. Two axis trackers are used to maximize power out put.
Govt. rebates :- In Rajasthan REDA is the govt. agency for registration of solar thermal & solar photovoltaic power plant.
- Rs.12/- rebate for 1KWh for photovoltaic power plant.(Commercial only)
- Rs. 10/- rebate for 1KWh for solar thermal power plant.(Commercial only)
- 100% depreciation for all
Cost and life of plant: The cost of 1KW power plant is approx. $8000/- (Rs.4.0 Lac)
The life of solar panel is 25years. The battery life is 5 to 8 years depends upon us.
In the last solar energy is pollution free energy. It helps to reduce global warming. It is energy for future. U.S.A, Canada and Australian govt. are giving individual subsidy $8000/- per KW. Our govt. should provide such subsidy. Govt. should impose carbon tax to huge consumers of electricity and discharges green house gases.
By: Chandanmal Jain
Mahaveer circle , Barmer(Rajasthan)