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Bess

Tales of BESS #4 - Case Study: Technical Due Diligence on two Greek BESS Assets

Jul. 18, 2025
2 minutes

Technical Due Diligence on two Greek BESS Assets: 100MW / 250MWh (GRC)

 

 

Greensolver performed the technical due diligence of two standalone BESS assets in Greece 100MW/250MWh in the context of the project’s financing.

 

 

This audit covered both:

Technical aspects:

  • Site assessment & permitting: grid connection agreement, permits, EIA, connection signal with TSO, compensatory measures
  • Review of the selected equipment
  • Design review and capacity to operate on primary reserve markets
  • Contracts review: BESS supply & maintenance, construction, RTM, TSO
  • Insurance policy coherence with technological risks

 

 

Financial/aspects:

  • Audit of the revenue scenarios and Assumption sheet (revenue stacking), including FCR, aFRR, CRM, voltage supply markets, imbalance market
  • Review of the inputs of the financial model and validation of the Assumption sheet : CAPEX, OPEX, budgets, revenues, IRR

 

 

Based on the reviewed technical capabilities of the BESS project, Greensolver audited the expected revenue streams of the two BESS project. Our best expert analysed the detailed financial models provided by the project developer, encompassing all the types of (ancillary) services to be serviced by the BESS, according to its constructive capabilities.

Our expert detected many inconsistences & issues in the financial model due to assumptions with needed to be modified and discussed with the project’s sponsors, its consultant and the potential lenders.

 

 

These discussions allowed to have more a robust financial model. Our expert has also identified points of attention to be discussed and negotiated with the RTM operator and the TSO, in order to achieve the revenues and the economics of the BESS.

Battery energy storage system

Written by David Roissé

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