| Energy Source | Type | Efficiency | Estimated Harvested Power |
| Light | Outdoor/Indoor | 10% - 25% | 100 mW/cm2 |
| Thermal | Human Industrial | ~0.1% ~3% | 60 µW/cm2 ~1 - 10 mW/cm2 |
| Vibration | ~Hz-human ~kHz-machines | 20% - 50% | ~4 µW/cm3 ~800 µW/cm3 |
| Electromagnetic | 900 - 2700 MHz Wi-Fi, WLAN | ~50% | 0.1 µW/cm2 0.001 µW/cm2 |
| RF GSM 1 GHz | Wireless GSM | ~50% | 0.1 up to 1 mW/cm2 |