Grenergy Renovables has finalized its first financial tolling agreement for a standalone battery energy storage system sited in Oviedo, Spain, the company announced.
The counterparty is described as an international utility with an investment grade credit rating from Moody's. Under the terms of the deal, the agreement will cover the day-ahead price spread on 80% of the project’s total capacity, based on an operational assumption of 1.5 cycles per day.
The contract runs for 10 years and is scheduled to commence in January 2028. The Oviedo project itself is designed with an installed power rating of 150 MW and an energy capacity of 600 MWh, and Grenergy expects the batteries to be operational in the first quarter of 2027.
Revenue streams for the asset will extend beyond daily trading: the project will also participate in all markets, including ancillary services, providing additional sources of income. The company noted that if Spain introduces capacity payments, those would represent another potential revenue channel for the facility.
Grenergy will retain responsibility for the operation and management of the battery installation. The batteries are estimated to have an operational life of about 20 years.
Contextual details and commercial structure
The financial tolling arrangement focuses on day-ahead price spreads, with coverage applied to the majority share of the project’s capacity rather than the full output. The use of an investment grade utility as counterparty is explicitly referenced, and the pricing exposure is specified to start under a fixed 10-year timeframe beginning January 2028.
Timing and lifecycle
The timeline provided indicates commercial operations are expected in the first quarter of 2027, with the tolling contract activating roughly a year later. The explicit operational lifetime estimate for the batteries is 20 years.
Financial implications noted by Grenergy
In addition to earnings from day-ahead trading spreads, Grenergy highlights revenue diversification through participation in ancillary service markets and other market segments. The company also references the possibility of future capacity payments in Spain as an additional income source, should such payments be introduced.