The battery system will be integrated with Ecorus’ 25.5 MWp Heldair II solar park and directly supply a nearby Fastned fast-charging station through a cable pooling arrangement, despite the project having 0 kW of contracted grid consumption capacity.
Den Helder, the Netherlands, 1 July – Ecorus has reached Financial Close for the 9.6 MW / 18.5 MWh battery energy storage system at Heldair II, in collaboration with ING. The transaction follows the financing of the Heldair II solar park in December 2024, which has since been completed. The addition of battery storage marks the next step in the development of Heldair II, combining solar generation, storage and EV charging within one co-located energy system. The BESS will be connected to the 25.5 MWp solar park and a nearby Fastned fast-charging station in Den Helder. Ecorus is the developer of the project and will also act as the main EPC contractor for the BESS.
Developed within severe grid constraints
Heldair II is located in one of the most grid-congested regions of the Netherlands. New requests for grid consumption capacity in the Den Helder region are on hold until 2036. The solar park has secured a grid connection for electricity export, but has 0 kW of contracted grid consumption capacity. Electricity can therefore be supplied to the public grid, but cannot be imported from it. At the same time, Fastned plans to operate a fast-charging station adjacent to the project without its own contracted grid consumption capacity. To make this possible, Fastned is connected directly to the Heldair II energy system through a cable pooling arrangement. Electricity for the charging station can be supplied from the solar park and BESS, while Heldair II itself remains connected to the public electricity grid for export only.
Adding storage to secure local energy supply
Battery storage is a key component of this configuration. Ecorus analysed the expected solar production of Heldair II together with the anticipated demand from the Fastned charging station. The resulting system design combines 9.6 MW of battery power with 18.5 MWh of storage capacity. This enables solar electricity generated during the day to be stored and used when generation is insufficient, supporting year-round energy availability for the charging station without importing electricity from the public grid. A site-specific Energy Management System will coordinate the different assets and energy flows, ensuring the system remains within its technical and contractual boundaries.
From Financial Close to realisation
Reaching Financial Close brings together a project with several interdependent components: an operational solar park, battery storage, a direct connection to Fastned and a grid connection that can only be used for export. The BESS Financial Close builds on the existing collaboration between Ecorus, ING and Fastned. Fastned and Ecorus have a long-term agreement under which renewable electricity from Heldair II supports Fastned’s charging network in the Netherlands. With financing secured, Ecorus will now move forward with the realisation of the BESS, with early 2027 currently targeted for completion.
