Frequently Asked Questions for Grid Connected Solar Rooftop PV Power Plants

Q 1. What is a Solar Rooftop System?

A. In a solar rooftop system, the solar panels are installed on the roof of any building like residential, commercial, institutional and industrial buildings.

Q 2. How many types of Rooftop Solar PV systems are there ?

A. There are two types of Rooftop Power Plants (i) Solar Rooftop System or Off Grid Systems with storage facility using battery. (ii Grid Connected Solar Rooftop PV System.

Q 3. What is a Solar Rooftop System with Storage facility?

A. Such rooftop system has battery as storage facility. The solar electricity is stored in the battery and can be utilized during night also when the sun is not available.

Q.3. What is a Grid Connected Solar Rooftop PV System?

A. In Grid connected Solar Rooftop PV system the DC power generated from SPV panel is converted to AC power using power conditioning unit .Generated Power by this system during the day time is utilized fully for powering captive loads and excess power is fed to the Grid.Grid connected Solar Rooftop system is operational so 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.

Q 4. What are the advantages of Grid-Connected Rooftop Solar System?

A. i) Electricity generation at the consumption center and hence Savings in transmission and distribution losses ii) Low gestation time iii) No requirement of additional land iv)Improvement of tail-end grid voltages and reduction in system congestion with higher self-consumption of solar electricity v) Local employment generation.

Q 5. Is it required to install the Grid connected Rooftop Solar PV Power Plant on the Roof top of the Building?

A. It is required that Rooftop Solar Power Plant System should be located in the premises of the consumer."Premises" means rooftops or /and elevated areas on the land ,building or infrastructure or part or combination therof in respect of which a seperate meter or metering arrangements have been made by the utility for supply of electricity.

Q 5. What is the average cost of grid connected rooftop solar systems?

A. The Benchmark cost of Grid connected rooftop solar PV systems determined by MNRE is about Rs. 75 per watt or Rs. 7.5crore per MWp capacity.

Q 6. What is the size of grid connected rooftop solar system?

A. The rooftop solar systems from 1 kWp upto 1000 kWp or in combination can be set up. However as per the Rooftop Solar PV Regulations 2015 ,the maximum peak capacity of the grid connected rooftop Solar PV system to be installed shall not exceed 100 % of the sanctioned connected load/contract Demand of the consumer. Also the capacity of Solar Rooftop shall not exceed 25 % of capacity of the distribution Transformer or any other Transformer from which power is fed tothe consumer .For ex if sanctioned connected load of the building is 10 KW then maximum RooftopSolar PV Power Plant of 10 KW capacity can be installed provided the capacity of the distribution transformer to which the Solar Plant will be connected or from which power is fed to the consumer is at least 50 KV.

Q 7. How much roof area is required to set up the grid connected rooftop solar system?

A. About 10sq.m area is required to set up 1 kWp grid connected rooftop solar system. for ex installation of 5 KW system will require 50 sq.m south facing shadow free area.

Q 8. What is subsidy available on installation of Grid connected Solar Rooftop Power Plants ?

A. A provision of Central Financial Assistance of 30% of the total cost or Rs. 24 per watt or Rs. 2.4 crore per MWp under the Grid Connected Rooftop and Small Solar Plants Programme of the Ministry. This CFA is available only for following categories.

1. All types of residential buildings

2. Institutional : School health institutions including medical colleges & hospitals, universities, educational institutions etc.[including those registered under the Societies Registration Act 1860 and the Indian Trust Act 1882.

3.Social Sector Community centres, Welfare homes, old age homes, orphanages, common service centres, common workshops for artisans or craftsman, facilities for use of community. Trusts/ NGO voluntary organization /training institutions, any other establishments for common public use etc. [including those registered under the Societies Registration Act under the societies Registration act 1860 and the Indian Trust Act 1882.1

NO CFA is available for

(a) Private Industrial and commercial Profit making establishments, which claim, accelerated depreciation.

Q 9. What is the meaning of "Net Metering" arrangement?

A. It is an arrangement for measurement of energy in a system under which rooftop solar PV system installed at consumer premises delivers surplus electricity ,if any to the Distribution licensee after off-setting the electricity supplied by the distribution licensee during the applicable billing period.

Q 10. What is Net meteringMechanism ?

A. 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.

Q 11.How the consumer will be compensated for excess electricity injected in Grid by the Rooftop solar PV system installed?

A. In case of electricity injected in the Grid exceeds the electricity consumed by the consumer in the billing period ( Monthly electricity bill ) ,such excess injected electricity shall be carried forward to the next billing period as electricity credit and may be utilised to net electricity injected or consumed in future billing periods but within the settlement period (-from 1st of April in an English calendar year and ending with the 31st of the March of next year ) .At the end of settlement period any electricity credits ,which remain unadjusted ,shall be paid at the rate of Rs 2.0/unit by the distribution licensee.

Q 12. Is it required by consumer to change the electrical meter already installed in his premises?.

A. Yes in case beneficiary goes for a net metered Solar system,Bidirectional meter will have to be installed .This approporiate meter may be procured ,installed and maintained by the Distribution licensee at the cost of the consumer ,or the consumer if desires may procure the meter at its level and present the same to Distribution licensee for testing and installation.

Q. Whom should you approach for installation of Grid connected Net metered Rooftop Solar PV Power Plant.?

A. On Ministry of New and Renewable Energy (MNRE) website www.mnre.org list of Empanelled Channel partners is available or on UPNEDA’s website www.upneda.org firms approved through bidding may be contacted.

Q 13. Is any provision for availaing loans for solar rooftop systems available?

A. 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.

Q 14. In case of grid failure, is there any chance for shocks to the person who is repairing?

A. In case the grid fails, the solar power has to be fully utilized or stopped immediately feeding to the grid so as to safe-guard any grid person/technician from getting shock (electrocuted) while working on the grid for maintenance etc. This feature is termed as ‘Islanding Protection’.

Q 15. What are the grid connectivity levels for such systems?

A. The Projects under these guidelines fall within two broad categories i.e.(a) the projects connected to HT voltage at distribution network (i.e.11KV and above ) (b) the projects connected to LT voltage i.e. 400/415/440 volts (3-phase) as the case may be or 230 volts (1-phase). Accordingly, the projects may be under the following two categories.

Q 16. For additional information or any clarification whom should be contacted?

A. Contact at UPNEDA'S toll free No 18001800 005 ,at UPNEDA's Customer care No -9415609080 or mail at compneda@rediffmail.com