The number of installed stationary battery energy storage systems (BESS) is growing significantly. According to recent estimates, today’s annual global market volume of about US$1 billion is expected to increase more than twentyfold in less than 10 years, reaching a staggering US$20–25billion by 2024. Florian Mayr of Apricum Consulting looks at this growth in the context of specific use cases for storage in two of its most advanced regional markets, the US and Germany.