BOSS project

Danish battery system to balance tomorrow's renewable power grids

Monday 02 May 22


Chresten Træholt
Associate Professor, Head of Section
DTU Wind
+45 45 25 35 18

About the BOSS Project

BOSS is short for BOrnholm Smartgrid Secured- by grid connected battery systems

Purpose: The project will develop and demonstrate a 1100kW/1100kWh Danish battery system at Bornholm, exploring cost-effective and market-based battery services and business cases

Period: March 2019 – December 2022

Budget: Total: 30 million DKK. Grant: 19 million DKK (EUDP)

Watch a video about the project here

Partners and contributions

Danfoss: Delivering advanced converter solutions, providing inputs to control hierarchy requirements, and handling real time part of converter control.

Bornholms Energi & Forsyning and TREFOR El-net: Facilitating grid connection and clarifying related legal issues primarily with the municipality and Energinet.

DTU: Managing the project and leading the research activities focusing on the application of artificial intelligence in the control and operation of battery systems.

European Energy: Validating the project’s commercial perspective and working with the practical integration in existing or future solar PV projects at Bornholm.

Lithium Balance: Developing and demonstrating the battery management systems and site controllers.

Nuvve: Demonstrating Nuvve’s vehicle-to-grid (V2G) platform for aggregation, market access, and business models of battery energy storage.

PowerLabDK: Developing and demonstrating battery system control interfaces, data collection platform and data management system.

The BOSS project succesfully demonstrated a large Danish battery energy storage system at Bornholm, with the capacity of 1100 kWh, 1100 kW. Batteries are keys to retiring fossil-fueled power plants.

People walking near Åkirkeby at the Danish island of Bornholm might have looked twice as trucks with several outdoor, freezer-size lithium-ion battery and converter racks arrived at the local transformer station recently. Surrounded by multiple wind turbines and solar PVs, Åkirkeby is the perfect test site for the BOSS grid connected battery system. The project demonstrating the battery system is called BOrnholm Smartgrid Secured – by grid connected battery systems (BOSS), with the total budget of 30 million DKK, co-financed by the Danish Energy Technology Development and Demonstration Program (EUDP).

Goodbye fossil-fuelled power plants

Renewable technologies are becoming more cost-effective, and the need for integration of renewable energy sources (RES) into energy systems continues to attract significant political and business attention.
By increasing the share of RES in energy systems, flexibility becomes a top priority for power grids across the world. Through history, fossil-fueled power plants have ensured a balanced grid, and by phasing these power plants out, we need other technologies and solutions to keep power systems secured. Batteries are among the most attractive solutions, explaines Project Leader of the BOSS project, Dr. Seyedmostafa Hashemi Toghroljerdi from the Technical University of Denmark.
“It is important to develop, test and demonstrate battery systems that are fast, flexible, efficient, cost-effective, and cyber-secured. Within the BOSS project, in a close collaboration between academia and industries, we are developing and demonstrating exactly such battery systems, to meet needs of future renewable-based power systems”, says Dr. Seyedmostafa Toghroljerdi.

The capacity and features of the BOSS Battery System

The BOSS battery system installed at Bornholm has a capacity of 1100 kWh, 1100 kW. The BOSS project was uniquely configured to study how sizable, grid-connected battery systems can create value through various grid services. By demonstrating the BOSS battery system at Bornholm, it is now ready to provide various anciliary and grid services in the Nordic Region, including frequency regulation services and reactive power support. It can also be utilized to store excess electricity from flucturating energy sources such as wind turbines and solar PVs and feed the stored electricity back into the grid, when needed. Moreover, its special design principles and control features allows it to supply hundreds of customers when the connection to the main grid is not available or power outage happens in the main grid. Majority of these functionalities have been tested using the BOSS scaled-down system demonstrated at DTU, PowerLabDK. The scaled-down system has the same design, control and functinalites as the Bornhholm one, and has been in operation since 2021.

Next Step

BOSS project partners are now ready and eager to start tests and experiments in the field. It will give them valuable learnings on principal hardware requirements, control logics and regulatory frameworks, and the possibility to highlight BOSS battery system capabilities and novel solutions. Testing a broad range of innovative grid services and potential business cases will be done at Bornholm using the BOSS battery system.