PERFORMANCE OF CONICAL SOLAR STILL Smita B. Joshi Department of Physics, Sardar Patel University, Vallabh Vidyanagar

PERFORMANCE OF CONICAL SOLAR STILL Smita B. Joshi Department of Physics, Sardar Patel University, Vallabh Vidyanagar Abstract “KEDAR”, a laboratory scale solar still has being designed and developed offers high quality water because of the selection of materials viz.. Glass and copper. The model offers high efficiency as its conical shape allows the incident solar radiations independent of the position of the Sun. It can be used even during nighttime by supplying electrical back up (Hybrid model) which can distillate the water even at faster rate as the condensation rate depends on the difference of temperature of glass and pan. Application of black color on water pan can increase the absorption of solar radiation and hence its efficiency increases but at the same time it may add typical paint odor which makes the water non-usable. Application of coal instead of black paint can solve this problem as coal is cheap and easily available; it even works as deodorant for water which makes the water odorless. Coal starts fast evaporation even in early morning when solar radiation is inadequate. Application of Coal in monsoon season when the atmosphere is cloudy gives better performance. Wet ability of coal increases the effective evaporation surface area.

Forms of Energy

Gujarat State: Some Features An area of 1,96,000 sq.km Per capita consumption of electricity in : 1424 kWh (national average 717 kWh)

POTENTIAL OF RENEWABLE ENERGY IN INDIA India is well situated for exploring renewable energy resources. Being a tropical country, it receives solar insolation of the order of kw/m 2 /year for nearly days. Daily solar energy incidence varies between 5- 7 kwh/m 2 in different parts of country.

Potential of Solar Energy Larger potential for solar power  300 days of clear sun  Solar radiation kWh per sq.mt. per day

SODIS Solar Water Disinfection:

Impact Of SODIS

Design of KEDAR Solar Still

Comparison between Single cone and Double cone Solar Still Solar reflector Effect of coal

Comparison between solar still and distillery

Process Execution Electrical supply switched on at 2:22 pm Electrical supply switched off at 2:54 pm Distilled water obtained 338/32 minutes. Distilled water obtained 634/ hour supply of energy 220 volt x 8 Amp = 1760 watt nearly = 1.76 kw.

Drinking water standard

Advantages of Solar Distillation Solar distillation Environment friendly least costly Pollution free offers highest purity 99.99% true purification of most types of contaminated water -- especially in developing nations where fuel is too expensive.

CONCLUSION The water obtained is cheaper than bottled water, as there is no running cost. KEDAR model is eco friendly and cheaper than basin type solar still. The quality of water was tested at SICART and the results were very good.

References: Dayal, M. Renewable Energy : Environment and development M. A. S Malik, G. N. Tiwari, A. Kumar and M. S. Sodha, Solar distillation, pergamon press. N. Y H:\\SODIS-Solar Water Disinfection files

ACKNOWLEDGMENT The author thanks Prof. A.R.Jani for providing guidance and technical assistance.

Thank You

Efficiency of solar still η = ml /IA = 0.300x22.4/8oox0.04 =6.72/32 x100% =0.21 =7.5x 22.4 /800

Testing of water sample in SICART