Engie, MasPV sign long-term BESS power agreements in Spain, Guatemala

Return and Engie have signed a 10-year full tolling agreement covering three battery energy storage system (BESS) projects in Spain’s Basque Country with a combined capacity of 55 MW/220 MWh.

Return will own, develop, and operate the battery systems, while Engie will optimize their flexibility across Spain’s wholesale and balancing markets. Commercial operations are scheduled to begin by the end of 2027.

The companies said the agreement demonstrates how long-term commercial contracts can support investment in battery storage by providing predictable revenue for asset owners while securing flexible capacity for electricity market participants. Construction of the three projects is already underway.

Separately, MasPV has signed 15-year PPAs with Guatemala’s Empresa Eléctrica de Guatemala (EEGSA) and Distribuidora de Electricidad de Oriente (Deorsa) for its Estanzuela solar-plus-storage project.

The project, in Guatemala’s Zacapa department, will combine 130 MWp of solar generation with a 100 MWh battery energy storage system. MasPV said the project, which represents an investment of more than $100 million, is expected to begin commercial operation before 2029.

From pv magazine España