Energy Laws

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Energy Study Guide
Energy Laws
1st law of thermodynamics
The total amount of energy in the universe always remains conserved, or constant. However, energy can be changed
from one form to another.
2nd law of thermodynamics
Some energy is always wasted in the form of heat when chemical reactions like combustion occur.
Fossil Fuels
 Coal
 Oil
 Natural Gas
Primary energy source
Energy stored in c-c bonds
Energy released through breaking those bonds up
in the presence of oxygen (combustion)
EXAMPLE: CH4 +O2  CO2 + H2O
Used for electricity production, transport,
residential & industrial purposes
Pros – available, effective, cheap, easy to use
Cons - inefficient (30%), destructive mining
practices, CO2 production, non renewable, not
always domestic
Greenhouse effect
Caused by green house gasses in
the air soaking up solar radiation
and keeping from bouncing back
out into space (this heats up the
earth)
Nuclear Power
Fusion of Uranium 235 splitting of atoms release heat energy  can be used
to turn water to steam and spin steam turbines to generate electricity
Accidents
3 mile island & Chernobyl
Pros – less fuel needed, less waste, little to no emissions
Cons – more dangerous nuclear waste, higher potential for large accidents
Renewables
Solar
Active and passive
 Solar water heating
 Solar thermal power plants
 Photovoltaic cells
 Passive solar architecture
Wind
No emissions
Sporadic some environmental impact on wildlife, NIMBY problem
Geothermal
Geothermal power plants
Passive geothermal for home heating and cooling
Hydro
Dams generate free renewable energy but can cause heavy environmental impact
Biomass
Biofuels like ethanol and biodiesel
Waste to energy plants
Landfill recovery
Know how to read one of these
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