A homeowner reached out to us
looking for a rooftop solar photovoltaic (PV) solution, for his residence in
Bangalore. The homeowner shared the following inputs before we got down to
designing the system,

·        
Solar to be the primary source of power

·        
Looking for independence from frequent grid
outages

·        
Aesthetically good looking structures

·        
Structures to be raised so that roof can be
accessed freely

A 3 kW battery based system was
proposed with ~6 hrs of back-up to power loads such as lights, fans,
televisions, music system, mixer, refrigerator, computers, water purifier, washing
machine etc. The modules have been mounted on customized raised structures made
of galvanized steel. The structures are non-penetrating, causing no damage to
the rooftop and are designed to withstand high wind speeds. The structures have
been raised ~7 feet from the lower edge of the module allowing for roof to be
used for other purposes.

The system consists of 12 number
of 250 Wp polycrystalline solar modules of 14.9 % efficiency, a 4 KVA
intelligent off-grid inverter which Is capable of handling high overload
capacities, eight number of solar tubular lead acid batteries along with a
battery rack. The inverter has been programmed to give solar priority over the grid
to charge the batteries and feed the loads. The system has been provided with
protection devices such as fuses, MCBs, AC and DC SPDs for the smooth running
of the system.