Convert Watt-Hours to Petajoules
Convert Watt-Hours (Wh) to Petajoules (PJ) instantly and accurately.
Conversion Formula
PJ = Wh × 3.600000000e-12
About Watt-Hours
A watt-hour (Wh) is the energy delivered by 1 watt for one hour - exactly 3,600 J. It is the practical unit for small-scale electrical energy: a 10,000 mAh 5 V power bank stores 50 Wh; a laptop battery holds 50-90 Wh; a smartphone battery holds 10-15 Wh; an AA alkaline cell stores ~3 Wh. LED lamps labelled 9 W save 51 Wh/h over a 60 W incandescent. IATA dangerous-goods rules use Wh as the threshold for lithium batteries in aircraft: cells >20 Wh and batteries >100 Wh need special approval. 1 Wh = 3,600 J = 3.412 BTU.
About Petajoules
A petajoule (PJ) is 10¹⁵ J - the national energy policy scale. IEA reports primary energy in PJ/year: Sweden ~600 PJ; Germany ~12,500 PJ; the United States ~93,000 PJ. World total primary energy supply is ~605,000 PJ = 605 EJ. The 1883 Krakatoa eruption released ~200 PJ ≈ 48 megatons TNT. A 1-megaton nuclear weapon releases 4.184 PJ. Global annual steel production embeds ~38,000-47,000 PJ of energy. 1 PJ = 10¹⁵ J = 277.78 GWh = 238.85 ktoe = 23.88 ktoe.
Quick Reference Table
| Watt-Hours (Wh) | Petajoules (PJ) |
|---|---|
| 1 Wh | 3.6 × 10-12 PJ |
| 2 Wh | 7.2 × 10-12 PJ |
| 5 Wh | 1.8 × 10-11 PJ |
| 10 Wh | 3.6 × 10-11 PJ |
| 25 Wh | 9 × 10-11 PJ |
| 50 Wh | 1.8 × 10-10 PJ |
| 100 Wh | 3.6 × 10-10 PJ |