In Grid Connected Rooftop or small SPV Systems, the DC power generated from SPV panel is converted to AC power using Power Conditioning Unit (PCU) and it is fed to the Grid. These SPV systems generate power during the day time which is utilized fully by powering captives loads and feed excess power to the grid as long as grid is available. In case, where solar power is not sufficient due to cloud cover etc. the captive loads are served by drawing power from the grid.

• Solar PV Modules/Solar Panels – The Solar PV modules/Solar Panels convert solar energy to DC (direct current) electrical energy. They are available in different technologies such as crystalline silicon, thin film silicon, CIGS, CdTe, HIT, etc. Crystalline Silicon Solar PV panels are most commonly used in solar rooftop system. Multiple panels are connected together to form arrays as per the desired capacity of the system.
• Inverter – Inverter converts variable DC output of Solar PV panels into AC power. Inverter also synchronizes with the grid so that generated power from the module can be injected into the grid.
• Module mounting structure – The module mounting structure is the support structure that holds the Solar PV panels in place for full system life and is exposed to all weather conditions. These are normally fixed at particular angle and orientation in case of solar rooftop system. But these can also be of type that tracks the Sun, called as trackers.
• Bi-direction Meters – Meters are used to record the generation or consumption of electricity. Bi-direction (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.
• Balance of System – These consist of cables, switchboards, junction boxes, earthing system, circuit breaker, fuses, lightning protection system, etc.

Such SPV systems can be installed at the rooftops of residential and commercial complex housing societies, community centres, Government organizations, private institutions etc.

About 10-12 Sq.m of shadow-free area is required to set up 1 kWp Grid Connected Rooftop Solar PV System.

Solar modules (and cells within) need uninterrupted sunlight to produce maximum electrical energy. With the shadow even on a part of the module, the generation reduces to a great extent thereby wasting installed system capacity. Also, prolonged (regular, though intermittent) shadow on some cells or modules reduces their life substantially and these become useless much before their standard life of over 25 years.

Rooftop solar PV systems can be installed on any type of roof having sufficient load bearing capacity.

On a clear sunny day, 1 kWp solar power plant can generate around 4 to 5 units in a day.

No, the daily energy generation from the RTS shall be dependent on the temperature and solar irradiance among other parameters and these may not be same every day.

• Plant Location
• Quality of equipment used
• Number of sunshine hours
• Workmanship
• PV module tilt angle and orientation
• Module Cleaning
• O&M activities etc.

No. On exposure to sunlight and outside environment, the solar modules lose their generation capacity over time. This is called degradation. Typically, solar panels degrade at about 0.5% to 1% per year, meaning after 25 years they might still produce 75-80% of their original output.