Renewable energy projects can now store and sell curtailed power using co-located battery systems

New Delhi: The power ministry has allowed renewable energy projects to use electricity curtailed under temporary general network access (T-GNA) to charge additional co-located battery energy storage systems and sell the stored power, people aware of the development said.

A no-objection certificate will not be required from the procurer under the existing power sale agreement. The ministry, in a letter dated August 27 seen by ET, has clarified that stored electricity can be sold to any entity through power exchanges or other arrangements.

"To facilitate optimum utilisation of renewable energy (RE) generation, it is hereby clarified that RE projects, awarded under the applicable bidding guidelines, may utilise the renewable energy curtailed under T-GNA for charging an additional co-located BESS, not covered under the existing PPA/PSA (power purchase agreement/power sale agreements)," the ministry said.


The clarification follows representations made by the developers seeking an enabling clarification on the matter, which was recommended by the renewable energy ministry, a senior government official told ET.

In a representation made in June, the National Solar Energy Federation of India had said around 90% of the power scheduled under T-GNA in the northern region was being curtailed. The association had also made a case for the same and said that the merchant BESS would constitute a new element and would not form part of the contracted project configuration under power purchase agreement (PPA).

As the PPAs didn't explicitly provide for such an arrangement, member developers had approached the renewable energy development agencies including Solar Energy Corporation of India and NTPC, seeking project specific no-objection certificates to use curtailed energy for charging merchant BESS and subsequently sell the stored energy at their discretion.

The move by the power ministry brings relief to renewable energy developers, provides a route for developers to monetise renewable power that would otherwise be curtailed under T-GNA by storing it in a separately deployed, co-located battery energy storage systems and selling the stored electricity independently.

The additional battery energy storage systems should not be covered under the project's existing power purchase agreement or power sale agreement.

The clarification is aimed at facilitating optimum utilisation of renewable energy generation, the power ministry said. T-GNA allows power generators to temporarily access the interstate transmission system, but constraints in transmission availability may result in generation being curtailed, or electricity generated is not evacuated.

Developers had sought greater flexibility to use this curtailed power, including charging co-located battery storage and selling the stored electricity separately.