Geothermal Energy Presented by William Murray March 28

Geothermal Energy Presented by: William Murray March 28, 2007

What is Geothermal Energy? • Defined: Energy that is generated by converting hot water or steam from deep beneath the Earth’s surface into electricity. • Unique renewable • Natural Energy Flow – Heat Mining – Enthalpy

The Heat Source • Tiny quantities of radioactive isotopes liberate heat as they decay • Core heat transfer through convection • Accessible in locations where heats interior is brought within reach – Lithospheric Plates • Significant heat flow • Volcanic activity

The Heat Source Cont’d • High enthalpy systems are divided into two categories – Vapor Dominated • Best and most productive • Free of liquids – Liquid Dominated • Relies on water at boiling point • Often results in steam “flash” • Two-phase zone

Geothermal Potential • Nature of the resource – Fluid Temperature – Salinity – Fluid Pressure – Gas Content • Economies of Scale • Maximum efficiency

Four Main Types • • Dry steam power plant Single flash steam power plant Binary cycle power plant Double flash power plant

Dry Steam Power Plant

Single/Double Flash Steam

Binary Cycle Power Plant

Ground Source Heat Pump

Global Capacity • Worldwide use of geothermal 9. 3 GW – 28 GW used directly for heating – 100 GWt through ground-source heat pumps • Potential for 65 -138 GW • MIT claims 100 GWe by 2050 • 0. 3% of US energy consumption

Environmental Impact • Gaseous emissions – Less than 1/10 th of coal-fired carbon emissions – Dissolved gasses • Land use • Noise • Potential ground subsidence

Geothermal Usage • Iceland generates 26. 5% of energy from geothermal –. 1% Fossil fuels – 73% Hydro • In the US – Alaska (1 Plant) – California (4. 8% of electrical energy, 2. 4 GW installed capacity) – Hawaii (30 MW on largest island, 20% of electrical energy) – Nevada(15 plants, 254 MW) – Utah (reconstructed developing plants)

Applications in Belize • Belize is the only country in Central America that does not have the potential for geothermal energy according to the US Department of Energy

QUESTIONS? !!