S4 Almelo
Future proof performance

By future-proofing the S4 Almelo project, we are extending our ability to support grid imbalances over longer periods. This enhanced grid support is critical to enabling greater penetration of renewable energy into the Dutch electricity system, directly supporting the Netherlands’ ambition to reduce carbon emissions by 55% by 2030 in line with the Paris Agreement.

S4 Almelo has evolved in step with changing energy market dynamics and rising power demand. The project demonstrates S4’s ability to adapt and enhance existing assets by investing ahead of the curve to extend asset life, increase system flexibility, and deliver long-duration grid support. It reflects a proactive, portfolio-led strategy that anticipates future system needs and ensures continued relevance as the energy system transitions.

Technically, S4 Almelo exemplifies the evolution of energy storage solutions. The site has transitioned from a kinetic energy facility to a hybrid configuration combining kinetic storage and battery energy storage systems (BESS), and ultimately to a fully 4-hour BESS site. This phased development approach highlights S4’s capability to integrate next-generation technologies and actively future-proof its portfolio, positioning the project at the forefront of modern energy storage solutions.

S4 Almelo is designed and operated in full compliance with the highest Dutch and international safety standards. The installation fully adheres to PGS 37-1 guidelines for permitting and construction, ensuring safe design, installation, and operation of all electrical systems. 

The battery systems are IEC and UL certified, including UL 9540A-tested technology to guarantee proven fire and thermal safety performance. In addition, the project includes a comprehensive fire safety and emergency response plan, reviewed and approved by the Brandweer (fire brigade) and Omgevingsdienst, ensuring safe and coordinated operation under all conditions.

We meet the Dutch legal requirement for BHV (bedrijfshulpverlening) training. S4 have trained BHV employees, to ensure there is always adequate coverage for emergency response, basic first aid, and evacuation procedures. The certificates and training are renewed annually. 

All on-site technicians are VCA-accredited, ensuring they meet recognised safety, health, and environmental standards for working in operational and potentially hazardous environments. In addition, several personnel are NEN3840 certified for the safe operation and management of electrical installations.

For the Almelo BESS project, cooperation with the municipality of Almelo, the Province of Overijssel, and regional partners was organised through early coordination on permitting, spatial planning, and alignment with local sustainability goals.

S4 Energy worked in partnership with Energiefonds Overijssel and maintained transparent communication with relevant public authorities throughout the development and realisation phases.
The Almelo BESS installation contributes directly to the regional energy transition by improving grid stability and enabling greater integration of renewable energy.

The project provides local economic value through the use of regional suppliers and contractors and strengthens Almelo’s position as a centre for sustainable energy innovation in Overijssel.
Where possible, landscape integration and environmental measures were applied to ensure responsible site development and minimal local impact.