Off-grid Solar system is a battery-backed system and does not need to be connected to your electrical supply. This system is commonly used for backup power which may be used for running the loads in non-sunny hours e.g. powering traffic signals and streetlights, billboards, backup power for houses, pumps, etc. in cities and remote rural locations that have either fluctuating grid connectivity or do not have access to grid electricity.
The design of your Rooftop Solar PV system depends on the availability of electricity, power quality, electricity tariff and your energy consumption pattern.
If you have grid connectivity, we recommend on-grid systems because they can more economically meet your energy requirements and provide flexibility of using a grid-hybrid system also. By using grid-hybrid systems, you can even store solar energy generated during the day for your night-time loads. If you need to choose Solar PV systems for schools, colleges, etc. which are closed on weekends, you can use net-metering mechanism to feed-in the extra power to the grid thereby avoiding any loss of solar power generated.
If you don’t have grid supply or have a poor (fluctuating) voltage, you may consider an off-grid system. This system is more expensive than an on-grid system because of the additional installation and maintenance cost of batteries.