In one line
Energy storage technologies discharging for 10+ hours, targeting renewable integration beyond what 4-hour BESS can solve.
What it means
Long-Duration Energy Storage (LDES) covers technologies discharging for 10 or more hours — beyond the 2–4 hour duration where lithium-ion BESS dominates. Candidates include flow batteries (vanadium, iron), compressed air, pumped hydro, gravity, thermal, and hydrogen-electricity round-trip. LDES is technology-uncertain in 2026 with no clear winner; deployment volumes remain under 5 GW globally vs ~200 GW of 4-hour lithium BESS.
Related terms
Browse every term in the renewable energy glossary, or read the latest analysis on Battery storage.