Who are we?

Energy Storage NL is the business association for the Dutch energy storage industry and part of FME, entrepreneurs' organization for the technology industry.
With over one hundred members (companies, grid operators, research institutes and funders) we want to connect parties in a meaningful way to create sustainable business cases for energy storage and contribute to a successful transition to a clean, reliable and affordable energy supply.

Ambition and activities

A clean, reliable and economically viable energy supply, in which energy storage and conversion plays a prominent role.

Participants are affiliated with Energy Storage NL because of the broad and high-quality network of affiliated parties and contacts with government and stakeholders. They use Energy Storage NL to expand their own network and to exchange knowledge with other participants and the Energy Storage NL office.

Energy Storage NL uses this knowledge for high quality advocacy for the broad energy storage sector. Together with its participants, Energy Storage NL promotes the necessity of energy storage in the energy transition and offers members a platform to promote their products and services.


Energy Storage NL maintains contacts with external stakeholders such as Netbeheer Nederland (association of grid operators), Holland Solar and other industries. In this way, we promote a common voice for the deployment of energy storage in the energy system of the future. We are also a member of the European Association for Storage of Energy (EASE), where we contribute to the representation of interests in Brussels.


The Board is a balanced representation of the various participant groups within Energy Storage NL. Board members advise on the long-term strategy.


Maarten van den Heuvel

I have felt involved in our environment and the deployment of renewable energy for many years.

Since 2006, as director of Cirmac International, I have been actively involved in realizing worldwide projects for biogas reprocessing into green gas from both biogas and landfill gas. This green gas is used in various ways but also fed directly into the natural gas grid.

At Bredenoord in recent years (since 2014) I co-direct the development and deployment of innovative products, which achieve a significant reduction of both fuel and CO2 emissions for our customers. We do this with various systems, but central to this are our mobile storage systems (battery) in various forms. These products are used both stand-alone and hybrid.

In this way we try to adequately help steer the energy transition of which we are all a part.


Alexander Savelkoul

Meer informatie over Alexander volgt binnenkort op deze pagina.


Fokko Mulder

After studying physics in Leiden, I received my PhD on a solid state physics topic (cum laude). For about twenty years I have been associated with TU Delft doing research on energy storage materials, since 2008 as a professor in the Faculty of Applied Physics. The research includes battery materials, hydrogen storage and production methods. In terms of teaching, I helped shape the new master’s program “Sustainable Energy Technology” in Delft, and have been teaching various energy storage-related courses there since 2006.

The intention is to work on electricity storage and conversion solutions that should eventually be applicable on a large scale; the systems should be able to contribute to the coming energy transition. Hence, research is going into more efficient batteries based on hydrogen, lithium or sodium, and the production of hydrogen and ammonia as fuels and as industrial feedstock. I am (co-)author of about 150 publications in international scientific journals and of several patents. Furthermore, I am involved in committees of NWO, NVAO, and an international working group within the ‘EU-SET Plan’ in the field of battery research and development, among others.


Jeffrey Bartels

I’m Jeffrey Bartels and I believe that a sustainable world starts with us. You choose how you generate, use, sell and share energy with others. And you have all the financial benefits. You are helped by an ICT company that analyzes data and not by an energy company that burns gas.

Hans van der Spek asked me to join the board in 2016. Not because I have so much board experience, but because I know how our members can optimally deploy certain assets (such as batteries) in the energy market.

The experience I have since gained on our board is very positive: the board members are very active and together we know how to put energy storage well on the map. And I am proud to be able to make my contribution!

I live in Amstelveen, have a wife and two children and play water polo in my spare time.

Feel free to give me a call if you want to know something or send me an email!


Margien Storm van Leeuwen

Drs. Margien Storm van Leeuwen studied Chemistry at Utrecht University. She worked at DSM, NedStack and Bredenoord and worked as product manager, purchasing manager, sales manager, business development and held various positions in management teams. She loves the combination of new technology and marketing in the field of energy transition.

Thus, she worked with various plastics, coatings, fuel cells, generators, batteries, PV and renewable fuels. Currently, she is Chief Commercial Officer at QuinteQ, a young high-tech company focused on developing, manufacturing and marketing the most advanced flywheel that fits the emerging need for robust storage technology in defense, subways and trains, fast charging plazas for larger electric logistics, ports and cranes, and various microgrids in industry with infinite cycles and circularity.


Ruud Nijs

I really want to help make the world a little better, and to do so in a business-like way.

Since 2018, I have been the CEO of GIGA Storage. GIGA storage develops, manages and invests in large-scale battery storage in Europe. It invests in projects for both grid stability and optimization of energy supply.

Before that, I focused on sustainable finance and Artificial Intelligence (including neural networks). I had the opportunity to work at both ABN Amro Bank and Rabobank for many years, with my last role at Rabobank being Director of Corporate Social Responsibility. I have also had the opportunity to sit on various Investment Committees of sustainable funds and have been involved in entrepreneurship in developing countries through BID Network and IFAD.

Energy storage, in my opinion, is incredibly important to keep our electricity grid stable and ready for the future, where much more real green energy is being generated in many places around the country.


Koen Broess

Dr. Koen Broess has a PhD in biophysics and a master’s degree in chemistry. As segment leader of energy storage & EVs, he is responsible for business development in Northern Europe. He is also key account manager. He has more than 11 years of experience with energy storage projects, new services and business models in the energy market and has set up and coordinated several (inter)national projects. He is responsible for quality control of proposals and involved in the development of the battery safety test center. At the national level, he was involved in the Dutch climate agreement, the energy storage roadmap and the electric vehicle batteries roadmap for the Dutch government. He is a member of the Ministry of Infrastructure and Water Management’s working group on battery safety and regulation. He is a member of the executive board of the European Association for Storage of Energy (EASE).

Hans van der Spek

I am the “founding father” of Energy Storage NL. The platform grew out of a theme afternoon I organized in 2013 on energy storage. That turned out to be so successful that I started to further develop the shared interest into Energy Storage NL together with a network of professionals and interested parties.

I work at FME, entrepreneurs’ organization for the technological industry, where I am program director CleanTech and cluster manager energy. I am also a board member of the TKI Smart Grids and coordinator of the ‘innovation and commercialization’ domain of the National Energy Agreement.


Siebe Geerts

After my bachelor’s degree in engineering (2011), I worked for several years as a production manager, including in my parents’ company (RENA; development and production of control electronics and LED technology). An internship in Canada, and a long trip through North and South America stimulated my interest in international business. Therefore, I took the plunge and left for China, where I lived and worked for 5 years. Active in supply-chain & manufacturing for the first few years, then moved on to product development and product management within a fast-growing startup.

Meanwhile, my dad had sought and found another challenge, “something with thermal storage. After looking into the (potential) role of Thermal Energy Storage in the energy system of the future, I decided to come back to the Netherlands, and contribute to the heat transition with HoCoSto.

My first period at HoCoSto was mainly operational: preparing and supervising some pilot projects. This is now shifting more towards facilitating the growth of the company. We are building a young and ambitious team, with common interests in innovation, technology and sustainability. We focus on scaling up the application of peak and seasonal buffers in collective heat systems, complemented by smart controls and optimal energy management.

Project Office

The project office focuses on the day-to-day operations of Energy Storage NL.