⚡ Energy Calculator
Efficiency, Sankey diagrams & the 10% rule
Efficiency Calculator
Efficiency = (Useful ÷ Total) × 100%
Total Input
J
Useful Output
J
25%
Wasted:
75 J
Useful 25J
Wasted 75J
Real-world examples:
💡 Old filament bulb: 5% efficient
💡 Korean LED bulb: ~80% efficient
🚗 German car engine: ~25%
⚡ Electric motor: ~90%
☀️ Solar panel in Nanjing: ~22%
🌊 Three Gorges Dam: ~46%
🌿 10% Rule — Food Chain Energy
Producer Energy
kJ
📊 Compare Efficiency
5%
Filament bulb
80%
LED bulb
25%
Car engine
90%
Electric motor
22%
Solar panel
46%
Hydroelectric