The Maharashtra Electricity Regulatory Commission (MERC) has approved Brihanmumbai Electric Supply and Transport Undertaking’s (BEST) to procure 400 MW wind-solar hybrid power from Solar Energy Corporation of India (SECI).

In a petition, BEST had asked MERC’s approval to sign  Power Sale Agreement (PSA) for 400 MW of wind-solar hybrid power from SECI at a tariff of ₹2.41 (~$0.0326)/kWh discovered through competitive bidding plus SECI’s trading margin of ₹0.07 (~$0.0094)/kWh for 25 years.

The power was to be procured from SECI’s 1,110 MW interstate transmission (ISTS) connected wind-solar hybrid power projects (Tranche-III). In the auction held in December 2020, ABC Renewable Energy, a subsidiary of Axis Energy, was awarded 380 MW of projects, Adani Renewable Energy Holding Eight Limited was awarded 600 MW, and AMP Energy was awarded 130 MW for ₹2.41 (0.0326)/kWh. ACME Solar quoted ₹2.42 (~$0.0327)/kWh for 300 MW of projects but was only awarded 90 MW under the bucket-filling method.

Initially, SECI had approached BEST for 600 MW of wind-solar hybrid power at ₹2.41 (0.0326)/kWh plus SECI’s trading margin of ₹0.07(~$0.0094)/kWh. However, BEST consented to the signing of PSA for 400 MW.

The Commission said that the power procured from SECI would be considered for meeting BEST’s solar and non-solar renewable purchase obligations (RPO).

The Commission observed that BEST needs to enter fresh contracts for the balance quantity since it only had an existing solar energy contract that provides annual energy of around 32 MU.

As per BEST’s submission, the power supply from the proposed hybrid projects is expected to start from FY 2023-24. The renewable energy requirement for FY 2023-24 is 968 MU, while the proposed hybrid project would be supplying 1,371 MU which is more than the power required to meet the RPO.

The Commission also considered the rate of ₹2.48 (~$0.033)/kWh, which is lower than the variable cost of the power sourced from thermal stations and lower than the short-term power procured from other sources. The excess power would help BEST to lower its procurement cost and meet future RPO targets.

In April 2019, the Commission had ordered five entities, including BEST, to comply with their solar and non-solar RPO requirement for FY 2017-18 and FY 2018-19.