Solar rooftop power plant generates adequate energy for any consumer, from the energy received by sunlight throughout the day. Solar PV (photo-voltaic) is a technology that works on the principle of converting light energy to electrical energy.

Cross-section of a Solar PV cell

In this system, the Solar PV panels generate Direct Current (DC) electrical power when sunlight hits their surface. Solar PV panels are manufactured by connecting a series of Solar PV cells in a circuit that generates enough energy to be made useful.

Multiple Single Solar PV Cells in a Single Solar Panel. || Multiple Solar Panels in a Solar Array

Each Solar PV cell, on its own, produces very little power that could be of any use. To overcome this limitation they must be combined in multiple numbers as one circuit (as a module/panel) to make it practically useful. On Solar Rooftop installation, we use multiple such solar modules in an even larger circuit (called a Solar Array) to further scale its potential to achieve the desired capacity as needed.

Electricity Supply Company Grid Operator (Eg. BESCOM)

This generated electrical power is a Direct Current, but the electrical connection that is supplied by the grid electricity supply companies (such as BESCOM, GESCOM, HESCOM, etc..) is of Alternative Current (AC) in nature. Therefore in order to make it useful just like the grid, we use an Inverter to convert the DC power to AC power.

Since our intention is to reduce electricity consumption (to save on expensive electricity bills), we need to connect the Solar Rooftop system to transact with the grid. So in this case, a specific type of inverter is used that is widely known as a "Grid-Tied Inverter", also known as an "On-Grid Inverter".
The on-grid inverter is designed to work in synchronization with the electrical grid and cannot operate on its own. This means that, if the grid-supply fails, the inverter also shuts down and no power is converted from the Solar PV panels. This is a safety feature incorporated (international standard) within the design of the inverter for safety reasons.

Now this converted AC electricity that the On-Grid Inverter supplies will be utilized locally within your building, any electrical power that is unused which is an excess generation will be sent back to the grid through a bi-directional energy meter.


A bi-directional energy meter is an electrical energy meter that records both the consumption (import of electrical energy) from the grid and also the production (exported electrical energy). The Rooftop-Solar system that is installed on most of the buildings is transacted with a billing scheme popularly known as net-metering. Sometimes the bi-directional meter is also called as Net-Meter for this particular reason.

The energy transactions recorded in the bi-directional energy meter are used to generate electricity bills. In the electricity bill, the consumed energy is charged according to the regular tariff after deducting the (Solar) energy that was exported back to the grid. If the energy exported is more than consumed, then the consumer will be credited with the amount according to the Solar tariff that is as per the contract agreed.


Currently (for F.Y. 2022-23), the Solar Net-Metering Tariff is at INR 4.02 per unit (kWh) for domestic consumers, while the tariff for commercial consumers is INR 3.19.


New domestic installations can avail of Subsidy up to (maximum) INR 94,522/-, for up to 10kWp capacity. Check out the calculations table on the Calculator page.