Rooftop Solar
What is Rooftop Solar?

Solar Photovoltaic modules and allied electrical equipment are installed on residential and commercial rooftops and connected to the power grid. These are known as Grid- connected Rooftop Photovoltaic systems. The GRPV system comprises of electrical and electronic equipment, such as solar modules, inverters, cables, switch gears, etc. When all these components are combined together and placed in open space facing sunlight, the system starts generating electricity proportional to the intensity of sunlight. The electricity, thus generated, can be used directly by the consumer. If consumer is not able to use complete electricity generated by GRPV system, the excess electricity generated can be fed to the utility grid (DISCOM network) and the units get adjusted in the electricity bill. It is important to mention here that 1 kW of solar PV plant can generate more than 1200 units of electricity in a year.


The function of each component of solar PV system is explained as follows:

Solar PV Modules

Solar PV Modules are in the form of flat, rectangular panels which convert sunlight directly into electricity. Multiple panels are connected together to form arrays as per the desired capacity of the system.

Solar Inverter

Solar Inverters convert the DC electricity produced by the PV panels into AC electricity which can then be consumed by appliances within the premises or injected into the DISCOM grid.

Balance of System (BoS):

All components, other than the PV modules, are termed as balance of system. The components included in BoS are:

  • Mounting Structure: The mounting structure supports and holds the PV panels in place on the roof. The structure is designed depending on the roof type, structural strength, cost, wind loads, etc.
  • Wiring and cabling: DC cables are used to connect solar panels and connect the array with the inverter.
  • Safety equipment: Safety features protect the solar PV system from being damaged or harming people in events, such as lightning, power surge or malfunctioning of equipment. The safety equipment consists of safety disconnect, grounding equipment, and surge protection.
  • Bi-directional Meters: Bi-directional meters (or “Net” Meters) are used to keep track of the electricity that solar PV system injects to utility grid and the electricity that is drawn from the utility grid.