DNV, the independent energy expert and assurance provider, has acted as technical advisor during a technical due diligence (TDD) process for financing of a €50 million portfolio of three standalone battery energy storage systems (BESS) being developed by the independent energy storage provider and infrastructure developer, Return Energy, in the Spanish province of Bizkaia.
The projects, located in Güeñes, Barakaldo, and Lezama, will provide a combined power capacity of 55 MW and storage capacity of 220 MWh. The portfolio is, to date, the largest standalone battery storage portfolio in Spain to reach financial close.
As technical advisor, DNV provided an independent assessment of the project design, technology selection, contracts, and key technical risks, together with recommendations to mitigate those risks and support the financing process.
Spain’s electricity system is expected to require substantial growth in energy storage capacity as the share of variable renewable generation increases. BESS can help balance differences between electricity production and demand, support grid stability, and provide additional flexibility to the power system. The projects form part of Return Energy’s wider pipeline in the Basque Country, which exceeds 1400 MWh of energy storage capacity and 352.6 MW of power capacity.
Brice Le Gallo, Vice-President and Regional Director for Southern Europe, MEA & LATAM, Energy Systems at DNV, commented: “Energy storage is becoming an increasingly important part of Spain’s power system as renewable generation grows. DNV’s Energy Transition Outlook for Spain shows that a more electrified, renewables-based energy system will require substantially more storage to provide flexibility and support grid stability. Projects reaching financial close are an important part of moving energy storage development from planning into deployment. Our role is to provide an independent view of the technology, design, and technical risks so that the parties involved can make investment decisions with greater confidence.”
Steve Sceery, Country Head for Return Energy in Spain, added: “DNV has been a key partner to help us complete the financing for this landmark transaction in Spain. They brought to bear their full technical expertise on what is a new asset class here in Spain which was instrumental in ensuring a swift and successful transaction. We valued both their knowledge and agility in this process.”
Carlos Albero, Market Manager for Iberia, concluded: “DNV combines experience from established battery storage markets including the US, the UK, the Nordics, and Chile with its local energy expertise in Spain. Our work on the Bizkaia portfolio reflects the growing role of independent technical assessment as standalone storage moves from an emerging segment towards wider deployment in the Spanish market.”
Spain’s National Energy and Climate Plan foresees a substantial expansion of storage capacity by 2030: 22.5 GW, including 12.5 related to BESS. With deployment still at an early stage, projects now reaching financing and construction will help determine how quickly storage can scale alongside renewable generation.
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