The project focuses on the safety guidelines, regulations, and knowledge gaps surrounding Battery Energy Storage Systems (BESS) across various countries.
The report provides a review of these guidelines, with a particular emphasis on Denmark’s guideline, developed by the Danish Emergency Management Agency (DEMA). Aside from presenting a viable opportunity for energy storage or balancing electrical grids, BESS present significant fire and explosion risks, due to employment of Lithium-ion batteries (LIB), which are susceptible to thermal runaway (TR). These risks are heightened by the growing number of installations, and notable incidents have underscored the need for further development of validated safety measures.
However, Denmark's existing guidelines, particularly for fire and explosion safety, lack detailed provisions on several critical fronts, including risk assessment or wastewater management.
While identified as a key risk, the Danish guidelines do not provide detailed measures to mitigate thermal runaway, unlike other countries where Battery Management Systems (BMS) are recommended. Denmark also lacks specific protocols for Lithium-ion battery fire and explosion testing, e.g., UL 9540A, which is a benchmark test recommended in many other countries. Danish guidelines may furthermore provide more clarification on when and which suppression systems should be installed, depending on BESS design parameters. While Denmark emphasizes collaboration with fire services, there is a lack of clear tactics and water management strategies, a gap covered by countries like Sweden and Australia.
Some of the identified knowledge gaps include limited understanding of explosion prevention and fire suppression in large-scale BESS settings. Furthermore, practical fire risk assessment tools may improve the design process. Additionally, it is necessary to evaluate safety hazards in BESS installations built from 2nd life LIB.
To improve the existing Danish guidelines, a more detailed description of the documentation circulation and liabilities may be introduced and the application of standard fire testing, already used in other countries, would further improve safety. The guidelines may also specify preventive measures against the mechanical impacts and the risk assessment and hazard mitigation analysis could be used in situations where the expected design is outside the scope of the guidelines. Other aspects to be incorporated are guidelines on handling extinguishing water, contaminated runoff, and post-incident management.
Several research directions are suggested in this report including, development of practical fire risk assessment tools and approaches for BESS systems as well as investigating the critical conditions for explosions and explosion risk mitigation measures. Determining heat release rates and the heat fluxes at different distances from LIB and BESS system at different scales may further allow for more optimal design.
