The round-trip efficiency (RTE) of pumped hydro storage typically ranges from about 70% to 87%, with most sources and data converging on roughly 79% to 80% on average. This means that for every unit of electrical energy used to pump water uphill (store energy), about 79% to 80% of that energy is recovered when the water is released to generate electricity later.
When compared to other energy storage technologies, utility-scale batteries commonly operate with a slightly higher round-trip efficiency, averaging around 82% in 2019 in the U.S. This indicates that batteries generally lose less energy during the storage cycle than pumped hydro. Other storage technologies may vary, but pumped hydro is often noted for its large capacity and long discharge duration, making it very valuable despite slightly lower efficiency compared to batteries.
Summary comparison:
| Storage Technology | Typical Round-Trip Efficiency |
|---|---|
| Pumped Hydro Storage | 70% – 87%, often ~79%–80% |
| Utility-Scale Batteries | ~82% |
Pumped hydro remains the largest energy storage resource by capacity, providing about 92% of U.S. storage capacity as of 2020, despite its modestly lower efficiency compared to batteries.
In conclusion, pumped hydro storage has a somewhat lower round-trip efficiency than advanced batteries but offers significant benefits in scale and duration of storage, making it a crucial technology in grid energy storage portfolios.
Original article by NenPower, If reposted, please credit the source: https://nenpower.com/blog/how-does-the-round-trip-efficiency-of-pumped-hydro-storage-compare-to-other-energy-storage-technologies/
