The AmstelbatterEi: An innovative energy solution for grid balancing

Last Easter, it finally happened: the Amstelvogel laid its first egg – the AmstelbatterEi. A true milestone in the energy transition. A brand-new cooperative energy storage system (EOS) from the energy cooperative De Windvogel and Emmett Green has recently been operational at the base of the wind turbine in Ouderkerk aan de Amstel. It's the result of three years of intensive collaboration and preparation. A 2 MW/4 MWh installation that intelligently stores sustainable energy, can reduce grid congestion, and helps balance the electricity grid.

Cooperative ownership and professional implementation

The project is so special because of the collaboration between De Windvogel and Emmett Green. De Windvogel is a renowned energy cooperative that has been working for years on local ownership of sustainable energy, and Emmett Green is an independent consultant with experience in innovative energy solutions. Each party shares 50% responsibility for the battery's ownership.

Emmett Green served as the delegated developer and was therefore responsible for the entire process: from drafting contracts to coordinating the permitting process, coordinating with grid operator Liander and other parties, and conducting financial and technical feasibility studies. All of this was done in close consultation with the cooperative, ensuring a smooth collaboration.

Digital Twin for data-driven battery sizing

Prior to construction, Emmett Green developed its own digital twin of the site using its advanced Energy Management System (EMS): a simulation model that can calculate different battery sizes, capacities, and market strategies based on historical data. These simulations provided insight into how the battery, combined with the wind turbine, would behave in various electricity markets, such as imbalance, day-ahead, and intraday markets, and under various grid constraints.

The result? A well-founded choice for a 2 MW/4 MWh battery, capable of flexibly responding to price fluctuations and grid demands without hindering the wind turbine's ability to generate green energy. The beauty of it is that the same algorithms from this simulation phase are also used to control the battery in practice. What was calculated beforehand is therefore exactly what happens in real time.

MLOEA for smart behind-the-meter optimization

Another unique aspect of the AmstelbatterEi is the application of MLOEA: Multiple Suppliers on One Connection. In this setup, the wind turbine and the battery share the same physical grid connection and are co-located, but are administratively separated.

Because the battery uses the same grid connection as the wind turbine, no additional grid connection or transmission capacity is required from the grid operator. The battery is therefore fully charged using wind energy. Emmett Green's EMS addresses all limitations, ensuring the battery can be charged directly with the sustainable power generated by the Amstelvogel and discharged when the wind drops. This maximizes existing grid capacity, and the smart combination of technology and structure ensures that the wind turbine and battery reinforce each other.

The power of advanced control and market optimization

The battery is controlled by Emmett Green's Energy Management System (EMS). This system continuously analyzes the current situation: the Amstelvogel's production, the energy markets, available capacity, and connection restrictions. Based on this data, the EMS determines how the battery can be optimally deployed.

This happens incredibly fast. The wind turbine can vary its output by more than 500 kW in a second, and the EMS responds instantly. Simultaneously, the system continuously monitors market opportunities such as imbalance, intraday, day-ahead, and redispatch. When power is cheap, the battery charges. When prices are high, and demand is therefore relatively high, it feeds back into the grid.

Insights and future perspectives

As with any innovative project, the AmstelbatterEi also yielded valuable insights. The added value of the combination of technical expertise and local involvement from the Energy Cooperative was clearly demonstrated in the collaboration between Windvogel and Emmett Green. Both parties clearly share many common goals in realizing these kinds of projects, despite their different perspectives. The project also demonstrates that a business case exists for a battery that integrates with renewable energy sources and doesn't require its own grid connection.

At a time when grid congestion is one of the biggest challenges in the energy transition, the AmstelbatterEi shows that innovation lies not only in hardware, but also in smart organizational choices.

Emmett Green is proud to support this exciting project by providing simulation and control via the EMS, thus facilitating the smart MLOEA construction. Together, we are building a future-proof energy system.