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Jevons Paradox

Simulate how efficiency improvements can increase total resource consumption through the rebound effect. In 1865, economist William Stanley Jevons observed that improved steam-engine efficiency led to more coal consumption, not less.

Real-world scenarios

Parameters

50%

How much more efficient is the new technology? 50% means the same service uses half the resource.

5%100% (2× efficiency)200% (3× efficiency)
0.8

By what percentage does demand increase for every 1% price drop? 0 = no rebound, 1 = proportional, >1 = amplified.

0 (inelastic)1 (unit elastic)3 (highly elastic)
1,000 units/year
10010,000

Results

Original
1,000
units/year
Naive Expected
667
units/year (no rebound)
Actual (with rebound)
844
units/year
Net Change
-156 units/year(-15.6%)
Rebound Effect
53.3% of savings eroded
Moderate rebound

Consumption Comparison

Original1,000 units/year
Naive Expected (no rebound)667 units/year
Actual (with rebound)844 units/year

How the math works

Efficiency factor f = 1.500 — the new technology delivers 1.50× more service per unit of resource.
Effective price drop = (f − 1) / f = 33.3% — cost per unit of service falls by this amount.
Demand increase = elasticity × price drop = 0.8 × 33.3% = 26.7%
New consumption = 1,000 × (1 + 26.7%) ÷ 1.50 = 844 units/year
Jevons Paradox occurs when elasticity > f. Currently: 0.8 ≤ 1.50 → Paradox does not occur