In a solar rooftop system, the solar panels are installed in the roof of any residential, commercial, institutional and industrial buildings. This can be of two types
(i) Solar Rooftop System with storage facility using battery, and
(ii) Grid Connected Solar Rooftop System.
2. What is a Grid Connected Solar Rooftop System?
In grid connected rooftop or small SPV system, the DC power generated from SPV panel is converted to AC power using power conditioning unit and is fed to the grid either of 33 kV/11 kV three phase lines or of 440/220 Volt three/single phase line depending on the capacity of the system installed at institution/commercial establishment or residential complex and the regulatory framework specified for respective States. These systems generate power during the day time which is utilized fully by powering captive 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.
3. Where can such system be installed?
Such rooftop systems can be installed at the roofs of residential and commercial complex, housing societies, community centers, government organizations, private institutions etc.
4. How much area is required for a 1 kW rooftop Solar PV system?
A 1 kW rooftop system generally requires 12 sq. metres (130 square feet) of flat, shadow-free area (preferably south-facing). Actual sizing, however, depends also on local factors of solar radiation and weather conditions and shape of the roof.
5. What is the average cost of grid connected rooftop solar systems?
The average cost of grid connected rooftop solar systems is about Rs. 69 per watt
6. What are the subsidies/capital support available from the Government?
Subsidies are available from multiple channels for setting up Rooftop PV projects.
(1) MNRE (Central Govt.) Capital Subsidy at the rate upto 30% of the benchmark cost for general category states and GEDA (State Govt.) subsidy of Rupees 10,000/- per Kilowatt, upto maximum 20,000/- Rupees is being given in residential, institutional (hospitals, educational institutes, etc.), social sector etc.
(2) Commercial and Industrial sectors will not be eligible for the above mentioned subsidies. But they are give tax benefit like, Under section 32 of direct taxes any energy conservation device is eligible for 80% accelerated depreciation in 1st year & remaining 20% in 2nd year.
(3) Government Institutions including Public Sector Undertaking (PSU) shall not be eligible for subsidy; instead they will be given achievement-linked incentives/awards.
* The percentage of subsidy varies according to the state policies.
7. What are the other fiscal incentives are available for Solar Rooftop Systems?
There are provisions of concessional import duty/ excise duty exemption, accelerated depreciation and tax holiday for setting up grid connected rooftop power plants.
8. Is Loan Finance available and What efforts is the Government making to provide loans for solar rooftop systems?
Yes, Loan Finance is available and Department of Financial services has instructed to all Public Sector Banks to encourage home loan/ home improvement loan seekers to install rooftop solar PV plants and include cost of system in their home loan proposals. So far, nine PSBs namely Bank of India, Syndicate Bank, State Bank of India, Dena Bank , Central Bank of India, Punjab National Bank, Allahabad Bank, Indian Bank and Indian Overseas Bank have given instructions to extend loan for Grid Interactive Rooftop Solar PV Plants as home loan/ home improvement loan.
9. What are the models for implementation of Rooftop PV systems?
(1) CAPEX Model : Here, the entire system is owned by the rooftop owners. Responsibility of O&M for the system lifetime (25 years) is also with the rooftop owner. Developer is responsible for installing the system and initial 2 years O&M.
(2) RESCO Model : Here, the entire system is owned by the developer. Responsibility of O&M for the system lifetime (25 years) is also with the developer. Rooftop owners may consume the electricity generated, for which they have to pay a pre-decided tariff on a monthly basis. Excess generation may be exported to the grid, subject to availability of requisite state regulations.
10. Which model is best for me?
(1) For consumers that have adequate manpower/expertise for O&M, rooftop access concerns, availability of funds upfront, CAPEX model is better. Consumers in states that have net- metering regulations can take benefit of the same.
(2) On the other hand, consumers who prefer not to take responsibility for the system O&M, do not have rooftop security concerns and prefer to pay on a monthly basis rather than bulk upfront payment may choose to go for RESCO model.
11. What is net-metering?
The grid connected rooftop system can work on net metering basis wherein the beneficiary pays to the utility on net meter reading basis only. Alternatively two meters can also be installed to major the export and import of power separately. The mechanism based on gross metering at mutually agreed tariff can also be adopted.
12. What is feed-in-tariff?
In feed-in-tariff the Government offers a tariff for purchase of the solar power generated from such plants.
13. What are requirements from State to promote grid-connected rooftop solar systems?
(i) States should have conducive solar policy to allow the grid connectivity. (ii) State Regulators have issued tariff order for appropriate tariff, netmetering/feed-in tariff and the grid connectivity, and (iii) The Distribution Companies agree to allow grid connectivity and purchase the electricity on feed-in-tariff or through net metering arrangement.
14. I want to install solar panels on the roof of my property. How should I go about it?
Consumers can get On-grid & Off-grid rooftop systems installed on your roofs through MNRE channel partners to avail government subsidy. You can find our company name M/s. J. J. PATEL’ on a MNRE channel partners listit can be found at http://mnre.gov.in/filemanager/UserFiles/list-of-Accredited-Channel-Partners-Rooftop-Gridconnected.pdf
15. What are the advantages of Grid-Connected Rooftop Solar System?
(1) Central & State Government Subsidies available for residential, institutional (hospitals, educational institutes, etc.), social sector etc. connections
(2) Tax benefits are given by Government for commercial & industrial connections.
(3) Pay-Back Period of Solar rooftop system is approximately 04 years
(4) After pay back period electricity generated will be totally free uptillsystem life of 35 years.
(5) Performance Warranty of Solar Panels is for 20 years.
(6) No pollution is generated.
(7) Board Supplied electricity’s rates will be increasing at regular time interval.
(8) Electricity generation at the consumption center and hence Savings in transmission and distribution losses
(9) Low gestation time
(10) No requirement of additional land
(11) Improvement of tail-end grid voltages and reduction in system congestion with higher self-consumption of solar electricity