FREE ESSAY ON GEOTHERMAL ENERGY STUDY GUIDE

GEOTHERMAL ENERGY STUDY GUIDE

GEOTHERMAL ENERGY S T U D Y G U I D E
WHAT IS GEOTHERMAL ENERGY?
BASICALLY GEOTHERMAL ENERGY IS HEAT THAT COMES FROM WITHIN THE EARTH. "GEO" MEANS EARTH
AND "THERMAL" MEANS HEAT. GEOTHERMAL ENERGY IS EARTH'S INTERIOR HEAT MADE AVAILABLE BY
EXTRACTING IT FROM HOT ROCKS AND WATER.
HOW IS IT CREATED?
GEOTHERMAL ENERGY COMES FROM DEEP WITHIN THE EARTH'S CORE. IN THE UPPER MANTEL OF THE
CRUST IS WHERE THE HEAT IS PRODUCED MOSTLY BY THE DECAY OF RADIOACTIVE ELEMENTS. THROUGH
DIFFUSION THE GEO THERMAL ENERGY IS MOVED TO THE SURFACE OF THE EARTH. MOST COMMON
OCCURRENCES OF THIS GEOTHERMAL ENERGY ARE GEYSERS AND HOT SPRINGS. WHEN THE WATER OF HOT
SPRINGS AND GEYSERS ARE UNDER GROUND, IT CAN BE AS HOT AS 300 DEGREES FAHRENHEIT.
WHERE WAS GEOTHERMAL ENERGY FOUND?
THERE ARE TWENTY-TWO COUNTRIES IN THE WORLD THAT AT ONE TIME HAD GEOTHERMAL ENERGY POWER
PLANTS AND SOME HAVE BEEN SHUT DOWN ALREADY. THE UNITED STATES IS BY FAR THE BIGGEST USER
OF GEOTHERMAL ENERGY. THE WORLD'S LARGEST GEOTHERMAL POWER COMPLEX IS IN THE GEYSERS OF
NORTHERN CALIFORNIA. IN 1991 THE GEYSERS HAD A GENERATING CAPACITY OF 1,400 MEGA-WATTS
WHICH IS ENOUGH TO SATISFY MOST OF, IF NOT ALL THE ELECTRICAL DEMAND OF SAN FRANCISCO.
THERE ARE OTHER POWER PLANTS SET UP IN UTAH, HAWAII, AND NEVADA THAT USE GEOTHERMAL
ENERGY.
IS IT A VIABLE ENERGY SOURCE?
SEVERAL ATTRIBUTES OF GEOTHERMAL RESOURCES MAKE IT A GOOD SOURCE OF ENERGY. ENERGY CAN BE
EXTRACTED FROM THE RESOURCE WITHOUT BURNING A FOSSIL FUEL SUCH AS COAL, GAS OR OIL.
THEREFORE, CARBON DIOXIDE AND OTHER GASES FORMED DURING COMBUSTION OF FOSSIL FUELS ARE
NOT EMITTED INTO THE ATMOSPHERE WHEN GEOTHERMAL RESOURCES ARE USED. GEOTHERMAL FIELDS
PRODUCE ONLY ABOUT ONE-SIXTH OF THE CARBON DIOXIDE THAT A NATURAL GAS FUELED ELECTRICAL
GENERATING POWER PLANT PRODUCES AND NONE OF THE NITROUS OXIDE OR SULFUR BEARING
GASES. USE OF GEOTHERMAL RESOURCES IS ALSO BENEFICIAL BECAUSE GEOTHERMAL ENERGY REPLACES
THE USE OF IMPORTED ENERGY SOURCES, SUCH AS OIL. 
IS IT COST EFFECTIVE? 
THE LOWEST COST GEOTHERMAL PRODUCERS ARE NOW SELLING GEOTHERMALLY GENERATED ELECTRICAL
POWER FOR $0.015 PER KILOWATT HOUR. AT THE GEYSERS, THE WORLD'S LARGEST GEOTHERMAL FIELD,
POWER IS SOLD AT ABOUT 3 TO 3.5 CENTS PER KILOWATT HOUR. A POWER PLANT BUILT TODAY WOULD
PROBABLY REQUIRE ABOUT 5 CENTS PER KILOWATT HOUR. SOME GEOTHERMAL 
POWER PLANTS RECEIVE MUCH MORE PER KILOWATT HOUR DURING SOME TIME PERIODS BECAUSE OF
VARIOUS INCENTIVES RELATED TO RELIABILITY OF GENERATION AND POWER PROVIDED DURING PEAK
DEMAND.
BINARY CYCLE/FLASH STEAM POWER PLANTS
THE TWO DIAGRAMS BELOW SHOW HOW A BINARY CYCLE POWERPLANT WORKS AND HOW A FLASH STEAM
POWER PLANT WORKS. ALSO THERE IS A PICTURE OF A REAL BINARY POWER PLANT AND FLASH STEAM
POWER PLANT.