Type of energy storage | Efficiency | Life time 20 years | SOC−1 factor |
Ultra capacitor | 99% | none | 0.9 |
Lithium-ion battery | 96% | 1 - 2 | 0.3 |
lead acid battery | 75% | 4 - 6 | 0.5 |
Fly wheel | 93% | maintenance | 1 |
Flow battery | 80% | unknown | 1 |