This chapter examines hydrogen’s potential role in the electricity sector, focusing specifically on its contribution to addressing extended renewable generation shortfalls during Dunkelflaute events—periods of simultaneously low wind and solar output. While most power-system flexibility can be delivered through batteries, interconnection, and demand-side response, these options become insufficient or prohibitively costly during multi-day or seasonal energy deficits. In such circumstances, hydrogen offers a distinctive advantage as a form of long-duration and large-scale energy storage that can bridge prolonged gaps between renewable supply and demand. The United Kingdom’s Hydrogen-to-Power Business Model illustrates growing policy recognition of this targeted role, framing hydrogen as a complementary asset for system resilience rather than a mainstream source of generation. Nevertheless, hydrogen-to-power applications face significant barriers, including low round-trip efficiency, high capital costs, and uncertainties across the emerging hydrogen value chain. A balanced strategy therefore recognises hydrogen’s specific value where technical and economic conditions justify its use—namely in systems with very high shares of variable renewables, available storage infrastructure, and supportive policy frameworks—while relying on more mature technologies for short- and medium-term flexibility.