Spain, Oct. 28 -- DNV 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 independent energy storage provider and infrastructure developer Return Energy, in the Spanish province of Bizkaia.The projects, located in Gueñes, Barakaldo and Lezama, will provide a combined power capacity of 55 MW and storage capacity of 220 MWh. This 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 ...