Secondly cost of installing solar panel is very high and return on investment takes around 10-12 years in US. In India return on investment would be around 15-20 years. Maintaining solar panels isn’t easy, people are not trained to do so.

Lifetime of these solar panels is 15 - 20 years, thus they will cost more, will not supply enough energy (as needed) and will be more of a headache than help.

If solar panels were cheap and easy to work with Reliance Power wouldn’t have proposed 115 Gas powered power plants, they would have gone for solar panels. Secondly this kind of technology can only be used in deserts, do you know how many small plants rely on Sun’s light to grow? They wouldn’t get this energy if they are covered and shaded by solar panels because you’ll have to cover lots of land to put up such a power plant.

So solar plants are actually very bad for environment.
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But it is good to use solar panel. It heats the water naturally and prevent us from global warming. So, who so ever know the store of solar panels can be use and save environment from global warming
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It is unlikely we will see heavy industry using photovoltaic electricity for quite some time due to the much larger energy demand industry requires, but who knows where photovoltaic electricity will take us in future years

It is quite possible for a household to run completely off photovoltaic electricity from the use of solar panels, yet this is unlikely in most cases. The costs involved with supplying a whole house with electricity from solar energy would be quite high for the average homeowner. However, the use of solar electricity in the average home is still able to provide a substantial amount of electricity, reducing future energy bills
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Solar powered airconditioning is actually the use of Lithium Bromide Water Absorption Chillers designed to run on natural gas as a heat source but with hot water from an evacuated tube solar collector as the heat source. Therefore, they work rather well with natural gas as the backup. Also evacuated tube solar thermal actually works on cloudy and overcast days too though volume throughput must be reduced to maintain output temperatures.

Solar thermal systems have the capability of storing energy for some time in insulated water tanks so it’s not quite the use it, sell it or loose it of photo-voltaics.

The cost of a solar thermal would be much lower than photo-voltaic, probably $5,000 USD for the solar thermal versus $50,000 USD for photo-voltaic. Even if you take into consideration replacing the AC unit with a aborption chiller, it will still be a fraction of the cost of PV.

However, most people that can afford a conventional AC unit cannot afford both a Solar Collector system and an AC in the form of an absorption chiller so most people will just opt for a conventional AC.

Absorption Chillers have only recently been scaled down, traditionally they’ve been 150 ton and 300 ton plus units. A typical residential system would have to derate a 10 ton unit to provide the 3 to 5 tons needed for residential cooling hence you’re paying for twice of what you need. However there is one manufacturer of 3 ton chillers and I’m surprised that the Solar panel company whose link I’ve provided didn’t opt for that chiller (the other link).
References :
http://www.solarpanelsplus.com/solar-air-conditioning/
http://www.robur.com/us/products/gahp-line/air-to-water-reversible-heat-pump-ar-rtar-series/description.html