Approx 100 sqft is needed per KW of rooftop installation.
Yes the system will produce power in cloudy weather.
A 1KW PV system will generate about 1450KWH/year & 36000KWH in 25 years.
Normally it wont break as the PV module can resist a high impact loads but it can break if the impact load is greater than that specified by the PV module manufacturer.
A gird-tied PV system can run any type of load including air conditioners, heating elements etc.
Yes if you are not a beneficiary of subsidy.
The return of investment time of a PV system is typically between 3 to 4 years.
Residential, Institutional & Social Sector roof top projects can get subsidy. Private, Commercial and industrial sector cannot get subsidy but they can avail depreciation & tax benifits.