In my last post I had tried to explain what net metering was all about and how the billing mechanism is followed. Continuing with the same, I shall now try to cover as to who all are eligible for installing a net metering system and what are the terms and conditions. I shall try and explain using the policy being followed in Maharashtra State of India as an example.
Generally, everybody who is a client of a DISCOM (Distribution Company) or utility company which is offering net metering is eligible for the scheme. However, is Gujarat state of India, it is categorically mentioned that the applicant should be the owner of the rooftop. Also, the DISCOMs put a minimum and maximum limit on the size of plant that can be installed under the net-metering scheme. This limitation may have been put in place either due to infrastructure constraints or to minimise any losses to the DISCOM. Why? Well, if seen from the DISCOM's perspective, a person who opts for net metering is reducing what he/ she buys from the DISCOM (reducing their revenue while still using their infrastructure) and forces the DISCOM to buy power from an additional source.
Coming to the example of Maharashtra. Here, any person who is a client of the DISCOM is eligible to install a rooftop solar system with a net metering facility. By client, it means that the energy bill generated by the DISCOM should have this person's name mentioned on it. Anyone interested in installing such a system needs to apply to the DISCOM and get into a Power Purchase Agreement post approval of the application. The service is offered on a first come first serve basis.
So what are the limitations? Well, the rooftop solar plant capacity should not exceed the sanctioned load of the premises. Additionally, 40% of the capacity of the transformer supplying energy to the premises should not be exceeded. For example let your sanctioned load be10 KW and the transformed capacity be 200 KW. So as per rule 1 you can install a rooftop solar plant of capacity 10 KWp with net metering.
Now, this transformer would be supplying to a number of premises. Hence cumulative net metering load on the transformer should not exceed 80 KW (40% of 200 KW). Now if say other premises have already installed net metering worth 75 KW, then as per Rule 2, you can install a rooftop solar plant of capacity 5 KWp only even when your sanctioned load is 10 KWp.
Additionally, there are further limitations, if you have a single phase connection, the plant size cannot exceed 8 KWp. If you have a 3 phase 415 V connection the maximum plant size can be either 80 KWp or 150 KWp based on whether you are a rural or urban consumer. For industries with 11KVA connections, the plant size can vary from 80 KWp to 1000 KVA depending on your location.