Environmental Engineering Reference
In-Depth Information
Farms located in the ocean may have negative unintended im-
pacts on the ecosystem.
No waste disposal.
Geothermal
Geo
means "of the Earth," and
thermal
means "heat"; therefore, geothermal energy is using the Earth's heat to
generate electricity. Geothermal heat in the form of hot underground rock formations, molten rock, and hot
subterranean water is used to turn a water source into steam, which drives electrical turbines. The top three
countries in geothermal energy production are the United States, the Philippines, and Mexico. The system can
be used to heat a house in the winter and to cool the house in the summer. Currently less than 1 percent of hu-
man energy use is generated by geothermal. Scientists estimate that using 1 percent of the energy stored in the
top 5 kilometers of the Earth's crust would provide 250 times more energy than all the Earth's crude oil and
natural gas reserves combined.
Geothermal
Advantages
Disadvantages
Water and heat can be depleted, diminishing energy produc-
tion.
Lower CO
2
emissions than fossil fuels.
Geothermal energy is clean and somewhat
renewable.
There are limited locations for building plants since access to
geothermal activity is required.
Water supply is replenished by rain, and heat
is replenished by the Earth's interior.
Building a geothermal energy plant can diminish a fragile local
ecosystem.
Digging into underground sources of geothermal energy can
release hazardous gases, including hydrogen sulfide.
It is relatively inexpensive.
There is no waste disposal or transport.
There is low land disturbance. Geothermal
power plants do not have to be large.
Energy source (fuel) does not require trans-
port.
Ocean and Tidal Waves
Although the concept is not new, the collection of energy from ocean and tidal waves is not widely used at this
time. As shown in the figure below, this type of energy generation starts when the wave hits a platform, which
in turn pushes on air in a chamber, pushing on the turbine. This turns a generator to convert the energy into
electromagnetic energy. There are also other methods that capture ocean and tidal waves to generate electricity.
