About solar rooftop system

In grid connected rooftop solar system, the DC power generated from solar panel is converted to AC power using PCU/Inverter. We can use this AC power in our premises or fed to 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:Cables, Switchboards, Junction Boxes, Earthing System, circuit breaker, fuses, lightning protection system, etc.

1 kW Solar rooftop system generally requires 8 - 10 sq. meters of shadow-free area. However, actual area requirement may vary depending on the selection of solar module, and site location etc.

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.

Solar Rooftop systems can be installed on any type of roof having sufficient load bearing capacity. Generally the roof having its slop in south direction is most suitable for Solar Rooftop Systems.

On a clear sunny day, 1 kW Solar Rooftop System can generate 4 to 5 units in a day.

No, the daily energy generation from the Solar Rooftop System shall be dependent on the temperature and solar irradiance among other parameters and these may not be same every day. It is also depend on cleaning of Solar Rooftop System.

Plant Location

Quality of equipment used

No. of sunshine hours


Tilt Angle and Orientation of PV Modules

Module Cleaning

O&M activities etc.

No. On exposure to sunlight and outside environment, the solar modules lose their generation capacity and this is called degradation. Generally it is 0.8% during a year.

Cost of system and subsidies

The current cost of grid connected Solar Rooftop Systems can be seen on our website at https://sssolarsystem.in

Subsidy is available only for residential sector grid connected solar rooftop projects only. For other sectors e.g. Govt., institutional, social, commercial, industrial etc. subsidy is not available.

Subsidy @ 40% for project capacity up to 3 kWp

Subsidy @ 20% for project capacity beyond 3 kWp and up to 10 kWp

Subsidy @ 20% for GHS/RWA capacity up to 500 kWp (limited to 10 kWp per house and total upto 500 kWp)

Yes, But the consumer shall be required to pay some minimum charges like fixed charges, etc. even if the consumed energy is all self-generated. However, ‘electricity charges’, a major component of the monthly bill, can be reduced to zero by optimally designing and maintaining the SRT. The monthly electricity bill may come to zero in States which give revenue for surplus power generated.

Metering arrangement for solar rooftop

All solar PV systems generate power only during daytime when sun is available. In net metering systems, the generated power is utilized for self-consumption, and excess power is exported to the grid as long as grid is available. In case, where solar power is not sufficient due to cloud cover etc. and power consumption during night time, power is drawn from the grid to power the loads. A bi-directional or net meter records the energy flow in both the directions and at the end of billing period net energy used is calculated. The beneficiary has to pay for only the net energy used.

In gross metering the power generated from the Rooftop Solar plant is only fed to the grid. The system owner gets paid by the DISCOM for such exported power at a predefined tariff.

Yes, the plants which are not connected to the grid are normally called behind the meter plants or Off-grid Solar Plants and The subsidy is not available for such plants even for residential sector. However, it is required to follow rules and regulations specified for this purpose by the state authorities.

Installation of solar rooftop system

You can apply for installation of solar rooftop system through our website at https://sssolarsystem.in or contact us for the same.

Yes, The Solar Rooftop system under any framework like net or gross metering can be installed by the electricity consumer. So, if you have electricity connection in your name and you pay regularly the electricity bill in your own name and also you have the permission of use the roof for solar rooftop installation from the owner, you can install the Solar Rooftop system.

With several common rooftops available in a society, there is a great potential for harnessing solar energy through rooftop PV systems. The energy generated from these systems is used to offset the common loads of the society (common lighting, lift, pumps, etc.). A Net Meter shall be provided against, the Single Point Delivery (SPD) common meter of Cooperative Group Housing Society (CGHS). In this, the society ultimately gets benefitted in terms of reduced monthly electricity expenses.

Operation and maintenance of solar plant

Solar PV modules used in solar power plants /systems are warranted for their output peak watt capacity, which should not be less than 90% at the end of 10 years and 80% at the end of 25 years.

The mechanical structures, electrical works including inverters/charge controllers/maximum power point tracker units/distribution boards/digital meters/switch gear/storage batteries, etc. and overall workmanship of the SPV power plants/ systems are warranted against any manufacturing defects for a minimum period of 5 years.

Compared to most other power generating technologies, solar PV systems have very low maintenance and servicing requirements. However, suitable maintenance of a PV plant is essential to optimize energy yield and maximize the life of the system.

Some of the maintenance activities typically may include but not limited to the following:

Module cleaning is required periodically (dust, bird dropping and other debris can cause decrease in power generation). Periodicity depends on local conditions like dust, birds, air pollution, etc.

Other items should be checked periodically as stated below:

Checking module connection integrity

Checking junction boxes / string combiner boxes

Inspecting mechanical integrity of mounting structures

Tightening cable connections that have loosened

Replacing blown fuses

Repairing lightning damage

Repairing equipment damaged by intruders or during module cleaning

The solar modules are made up of toughened or tempered glass top and so are not easily broken due to monkeys or any falling objects. These can be broken if deliberately someone throws stones. Guarding of module surface with wire mesh is one solution for monkey menace, but not recommended because this regularly casts shadow on the modules.

General information about solar rooftop

India is endowed with vast solar energy potential. About 5,000 trillion kWh per year energy is incident over India’s land area with most parts receiving 3-5 kWh per sq. m per day. Based upon the availability of land and solar radiation, the potential of solar power in the country has been assessed to be around 750 GW.

National Institute of Solar Energy (NISE), An Autonomous Institute under the Ministry of New and Renewable Energy has estimated a potential of 43 GW for Grid Connected RTS in the country.

Government of India has set the target of installing 40,000 MW of Solar Rooftop (SRT) Power by the year 2022.