The European Bank for Reconstruction and Development is due to consider on 22 July an up to €30 million senior secured project-finance loan for a major expansion of the Tenevo hybrid renewable complex in southeastern Bulgaria.
The financing would support a 246 MW/512.5 MWh battery system developed by Tenevo Solar Technologies. The new two-hour installation will be co-located with an operational 242 MWp solar plant and an existing 65 MW/260 MWh battery.
Completion would give the complex total storage capacity of 311 MW/772.5 MWh, equivalent to approximately 2.5 hours of full-power discharge across the combined battery portfolio. The project is backed by Eurowind Energy and Renalfa IPP, the latter associated with Renalfa Solarpro Group and infrastructure investor RGREEN INVEST.
The proposed loan equates to roughly €58,500 per MWh of new storage capacity. That figure is not a construction-cost benchmark because the EBRD facility is expected to finance only part of the capital requirement, and no complete project cost has been disclosed. It does, however, demonstrate that commercial-scale battery portfolios are moving into conventional secured lending rather than relying exclusively on sponsor equity and grant support.
The co-location structure has several advantages. The battery can use the solar plant’s existing land, substation, grid connection and operating platform, while charging during low-value production periods and protecting the plant from curtailment and captured-price erosion. The four-hour duration of the existing battery complements the shorter new phase, giving the operator greater choice between high-power balancing services and longer energy shifting.
The revenue structure remains the decisive credit issue. No fixed tolling agreement, guaranteed availability payment or PPA-backed battery revenue has been disclosed. Debt service will therefore depend on some combination of wholesale arbitrage, balancing markets, ancillary services and avoidance of renewable curtailment. As competing Bulgarian batteries enter operation, income from individual balancing products may compress even while wider midday-evening spreads remain commercially attractive.
The EBRD decision is still pending, and first disbursement would be conditional on updated environmental and social documentation. Approval would nevertheless represent another step towards establishing Bulgaria as Southeast Europe’s most active utility-scale storage-financing market.
