Ocean Thermal Energy Conversion (OTEC)

OTEC harnesses the temperature gradient between warm surface and cold deep ocean water to drive a heat engine

Temperature Profile

Surface Temp28°C

Deep Water Temp4°C

ΔT24°C

Depth Intake1000 m

Controls

Surface Temperature: 28°C

Cold Water Depth: 1000 m

OTEC Efficiency

Carnot Efficiency8.1%

Real Efficiency (~50%)4.0%

Net Power (50 MW plant)2.0 MW

η_Carnot = 1 − T_cold/T_hot
T in Kelvin
Real η ≈ 50% of Carnot

About OTEC

OTEC is viable where ΔT > 20°C — tropical oceans between 20°N–20°S. The cold water pipe is the engineering challenge. Georges Claude demonstrated the first OTEC plant in Cuba (1930).