As the government lays out the policy architecture of the next phase of its flagship rooftop solar (RTS) scheme, the PM Surya Ghar Muft Bijli Yojana, industry leaders and experts are calling for integrating it with the battery energy storage system (BESS).
The Ministry of New and Renewable Energy (MNRE), as part of its consultations with think tanks, industry executives, vendors and discoms, has received proposals for BESS integration and expansion to rural areas, it told Business Standard last week.
While the consultations are at a preliminary stage and no decision has been taken, the intention is to identify implementation challenges and explore measures to support the long-term growth of the RTS ecosystem, the ministry said.
Battery storage can increase solar self-consumption, reduce grid dependence, and lower electricity bills, according to Alekhya Datta, fellow and director (electricity and renewables division), The Energy and Resources Institute (Teri).
Datta is part of the deliberations.
According to Teri’s preliminary assessment, rooftop solar, combined with appropriately-sized batteries, can generate value for consumers and utilities.
Datta highlighted the fact that hybrid BESS architecture would be preferable because it would include household batteries for consumer resilience, community or feeder-level batteries for local network management, and utility-scale systems for bulk balancing and renewable-energy integration.
If the BESS component is added as part of the scheme, the upfront investment could increase substantially requiring capital support.
“The support could be linked partly to actual discharge during evening and peak hours, when the value to the system is higher,” said Rohit Vijay, associate fellow, Centre for Social and Economic Progress.
However, he added that it could be enforceable only if eligibility was restricted to communicable inverters or battery management systems conforming to a notified protocol.
Experts also pointed out that financial assistance must be directed towards segments and interventions where market adoption would otherwise remain weak. “Support should be differentiated. Lower-income households need higher direct assistance and easier access to the roughly 7 per cent collateral-free loans that already exist, with eligibility drawn from databases the government already has, such as Pradhan Mantri Awaas Yojana or sanctioned load,” said Vijay.
Under the current scheme, the government has implemented utility-led aggregation (ULA) models for low-income households. Through this demand is aggregated and implementation is supported by distribution utilities. Under the model, the ministry has sanctioned about 1.3 million RTS installations across 10 states or Union Territories.
While this model, along with arrangements for tenants and housing societies, can help reach households without an owned roof or the ability to make the upfront investment, they need to become easier to implement at discom level, according to industry representatives.
They also call for avoiding sudden policy changes as those can be counterproductive. Shreya Mishra, co-founder of SolarSquare, a rooftop solar company, said that during the consultations with the ministry, there were representations about ensuring that there was no discontinuity in the market to restore consumer sentiment.
