Pumped hydro storage (PHS) and lithium-ion batteries differ notably in terms of round-trip efficiency:
- Pumped Hydro Storage Efficiency: PHS typically achieves a round-trip efficiency ranging from about 70% to 87%, with many sources converging around 80% efficiency for the full cycle of pumping and generation. The variability depends on the specific technology, site conditions, and operational parameters. Losses occur primarily during the pumping process and from evaporation but overall, the system is considered quite efficient for large-scale energy storage.
- Lithium-Ion Battery Efficiency: While not directly cited in the search results, lithium-ion batteries are well known to generally provide higher round-trip efficiencies, typically in the range of 85% to 95%. This means lithium-ion batteries can convert stored electricity back to usable power slightly more efficiently than pumped hydro, due to lower conversion losses.
Comparison Summary
| Aspect | Pumped Hydro Storage | Lithium-ion Batteries |
|---|---|---|
| Round-trip Efficiency | 70% to 87%, ~80% average | Usually 85% to 95% |
| Scale | Very large energy capacity | Modular, scalable but limited by size and cost |
| Lifetime | Several decades to 100+ years | Typically 10-15 years (utility scale) |
| Geography Dependence | Requires suitable topography | Location flexible |
| Response Time | Seconds to milliseconds | Milliseconds to seconds |
| Cost Efficiency | Low cost per stored energy over lifetime | Higher upfront cost, but improving |
In essence, lithium-ion batteries generally offer higher round-trip efficiency than pumped hydro, but pumped hydro excels in large-scale, cost-effective, long-duration storage with very long lifespans and grid stability benefits. The choice between them often depends on storage duration, scale, site conditions, and cost considerations rather than efficiency alone.
Original article by NenPower, If reposted, please credit the source: https://nenpower.com/blog/how-does-pumped-hydro-storage-compare-to-lithium-ion-batteries-in-terms-of-efficiency/
