Pumped Hydro vs Li-ion vs Flow vs Compressed Air vs Gravity
Grid Energy Storage Comparison
Comparison of 5 grid storage technologies — duration, efficiency, cost, lifetime, and deployment scale.
Pumped HydroLi-ionFlow (V-Redox)CAESGravity
Full Specification Comparison
| Specification | Pumped Hydro | Li-ion | Flow (V-Redox) | CAES | Gravity |
|---|---|---|---|---|---|
| Duration | 6-24 hr | 2-4 hr | 4-12 hr | 4-24 hr | 4-8 hr |
| Efficiency | 70-85% | 90-95% | 65-75% | 50-70% | 80-90% |
| Cost ($/kWh) | $100-200 | $150-300 | $200-350 | $100-150 | $150-250 |
| Lifetime (cycles) | 50+ years | 5,000-8,000 | 20,000+ | 30+ years | 10,000+ |
| Installed (GW) | 1,600 | 120 | 3 | 0.5 | 0.1 |
| Geographic Limits | Needs elevation | None | None | Needs caverns | Needs height |
| Response Time | Minutes | ms | ms | Minutes | Seconds |
Expert Verdict
Pumped hydro dominates with 95% of installed storage (1.6 TW); Li-ion is the fastest growing for 2-4 hr storage; flow batteries win for 8+ hr duration; CAES and gravity are emerging alternatives.
Subject Breakdown
Pumped Hydro
1 Category Wins
- ★ Installed (GW): 1,600
Li-ion
2 Category Wins
- ★ Efficiency: 90-95%
- ★ Response Time: ms
Flow (V-Redox)
1 Category Wins
- ★ Lifetime (cycles): 20,000+
CAES
0 Category Wins
Gravity
0 Category Wins