DERC Clears BSES Rajdhani’s 1.5 GW Solar Plus Storage Deal With SECI to Meet Delhi’s RPO, FDRE Goal

The Delhi Electricity Regulatory Commission (DERC) has recently approved BSES Rajdhani Power Ltd.'s petition to develop a large-scale storage project at a locked-in tariff of around ₹3.52–₹3.53/kWh for a 1500 MW Solar power with 750 MW/3000 MWh Energy Storage System (ESS) project. Post DERC’s approval, BSES Rajdhani can now buy 1,500 MW of firm solar power from SECI to meet Delhi’s renewable and reliability requirements at stable long-term tariffs.

This approval is subject to SECI’s trading margin and CERC’s directions. This would help Delhi meet its Renewable Purchase Obligation (RPO) and firm, dispatchable renewable energy (FDRE) needs. Moreover, it approved the Purchase Sale Agreement (PSA) signed between the parties, and DERC, in its latest ruling, approved the formal PSA signed on March 13, 2025.

This petition is also a major push toward integrating storage-backed renewable energy in a large urban grid (Delhi), which could improve supply stability, help meet peak demand, and support the transition to clean energy. Moreover, the decision also sets a regulatory precedent under ISTS-connected solar + storage PPAs, potentially paving the way for similar deals with other distribution utilities in Delhi or elsewhere.

Case Background

The latest case also allows BSES Rajdhani Power Ltd. (Delhi DISCOM) to meet its energy commitment of a total of about 3036.8 MUs annually, with flexibility margins (+10%/-15%) for 25 years.

The approval gives a broader grid-supply and reliability mandates, including firm/dispatchable renewable energy (with storage). Under the Power Sale Agreement, SECI invited bids (under MOP’s 2023 guidelines for firm & dispatchable renewable power + storage) for 2,000 MW ISTS-connected solar + storage. BRPL is committed to taking 1,500 MW + 750 MW/3,000 MWh storage after the competitive e-reverse auction. 

The competitive bidding resulted in a discovered tariff of ₹ 3.52–3.53/kWh (plus SECI’s trading margin). BRPL submitted this PSA for DERC’s approval, along with compliance with applicable Delhi regulations. 

Previous Solar Plus Storage Projects in Delhi

Delhi’s First BESS Project:
Delhi has been steadily expanding its battery energy storage capacity, beginning with its first commercial project supported by the Global Energy Alliance for People and Planet (GEAPP). The 20 MW/40 MWh BESS installation will be set up at BRPL’s 33/11 kV Kilokari substation. IndiGrid — an Indian power-sector Infrastructure Investment Trust (InvIT) — subsequently commissioned one of India’s first regulated utility-scale standalone BESS projects of 20 MW/40 MWh in Delhi, operated through Kilokari BESS Private Limited (KBPL).

Delhi Approves Petition to Develop 2-Hour BESS Project:
In a separate petition filed by BSES Rajdhani Power Ltd. (BRPL) for commissioning a 12.5 MW/25 MWh Battery Energy Storage System (BESS) at the 33/11 kV Shivalik Grid, the Delhi Electricity Regulatory Commission (DERC) has approved BRPL’s proposal for a 2-hour BESS configuration.

To meet the city’s growing requirements, DERC noted that a 2-hour BESS is adequate for peak shaving, frequency response and congestion relief at the distribution level. It further observed that a combination of 2-hour and 4-hour systems could effectively meet Delhi’s cumulative 4-hour storage needs.

Delhi Grants Approval for 500 MW Solar Plus 250 MW/1000 MWh ESS:
Delhi had earlier received another major clearance from BSES. On November 24, it secured a second, larger approval for an agreement signed on 13.03.2025 for 500 MW of solar power along with a 250 MW/1000 MWh Energy Storage System.

This project is part of SECI’s ISTS Scheme (Tranche XVII), which includes 2,000 MW of solar power with 1,000 MW/4,000 MWh of energy storage. The agreement executed between another Delhi discom, BSES Yamuna Power, and SECI discovered a tariff of ₹3.52–3.53 per kWh, plus the applicable SECI trading margin.

Among Delhi's three discoms, BSES Yamuna, BSES Rajdhani and Tata Power DDL which handles NDMC areas only, the national target of 43.3% for RPO or renewable purchase obligation is well within reach. Tata Power seems ahead of the curve at this stage, with the two BSES discoms now beginning to play catch up.