energy
Ability to do work
convection
Process by which, in a fluid being heated, the warmer part of the mass will rise and the cooler portions will sink.
conduction
Form of heat transfer where heat energy is directly transferred between molecules through molecular collisions or direct contact.
high quality energy
organized & concentrated; can perform useful work (fossil fuel & nuclear)
low quality energy
disorganized, dispersed (heat in ocean or air wind, solar)
power
the rate of doing work
power units
are watts and horsepower
turbine
machine that converts mechanical energy (wind, moving water, steam) into electrical energy by use of a generator
generator
A device that uses electromagnetic induction to induce electrical current by rotating loops of wire through a magnetic field
first law of thermodynamics
Energy can be transferred and transformed, but it cannot be created or destroyed.
second law of thermodynamics
when energy is changed from one form to another, some useful energy is always degraded into lower quality energy (usually heat)
fossil fuel
a nonrenewable energy resource formed from the remains of organisms that lived long ago; examples include oil, coal, and natural gas
coal seam
A layer of coal, usually 1 to 2 m thick.
natural gas
Fossil fuel consisting of methane that occurs naturally underground
methane
colorless, odorless, flammable gas present in natural gas and formed by the decomposition of organic matter; can be produced by living organisms
exploratory wells
used to drill and sample a particular area for fossil fuel deposits, can provide estimate the proven reserve
crude oil
petroleum as it comes out of the ground and before it has been refined or processed into useful products.
pressure extraction
when mud, saltwater, and CO2 are pumped into the ground to pressurize the oil so it comes to the surface
anthracite
the cleanest-burning coal; almost pure carbon.
underground mining
involves the sinking of shafts to reach underground deposits. In this type of mining, networks of tunnels are dug or blasted and humans enter these tunnels in order to manually retrieve the coal.
strip mining
a process in which rock and soil are stripped from the earths surface to expose the underlying materials to be mined
overburden
Overlying layers of soil and rock over mineral deposits. - Removed during surface mining
oil reserves
oil that has been discovered, but remains unused in the ground
shale oil
Slow-flowing, dark brown, heavy oil obtained when kerogen in oil shale is vaporized at high temperatures and then condensed. Can be refined to yield gasoline, heating oil, and other petroleum products
tar sands
Unconventional form of oil, liquid petroleum can be extracted with hot water, however not widely used because of the cost and environmental impacts.
electrostatic precipitators
A device used for removing particulates from smokestack emissions. The charged particles are attracted to an oppositely charged metal plate, where they are precipitated out of the air.
natural gas pros
ample supply, high net energy yield, low cost, low pollution emissions and environmental impact, easily transported, low land use, good fuel (fuel cells, gas turbines)
natural gas cons
Releases CO2 when burned, methane can leak- pipelines, shipped across oceans (Explosive LNG), burned off and wasted because of low price
coal pros
Ample supplies, high net energy yield, low cost
coal cons
highest environmental impact, severe land use and disturbance, severe land/air/water pollution, severe human health impacts, high CO2 and CH4 emissions, mercury and heavy metals, radioactive isotopes, SOX
petroleum pros and cons
cheap, easily transported, high-quality energy. Cons: reserves depleted soon, pollution during drilling, transport and refining, land subsidence, burning oil produces CO2
nuclear fission
Nuclear change in which the nuclei of certain isotopes with large mass numbers (such as uranium-235 and plutonium-239) are split apart into lighter nuclei when struck by a neutron. This process releases more neutrons and a large amount of energy.
parts of a nuclear reactor
core, control rods, moderator, steam, generator, turbine, containment building
nuclear power pros
(A) Large fuel supply
(B) Low environmental impact (without accidents) and emits 1/6 amount of CO2 as coal
(C) Less Land disruption
(D) Low risk of accidents
nuclear power cons
Waste product (spent fuels) and other radioactive waste difficult to store and contain; Must first be stored in pools to cool the fuel or in specialized dry storage; Water used in cooling process causes thermal pollution; Half life of uranium used for fue
half life
length of time required for half of the radioactive atoms in a sample to decay
meltdown
Severe overheating of a nuclear reactor core, resulting in melting of the core and escape of radiation.
thermal pollution
a temperature increase in a body of water that is caused by human activity and that has a harmful effect on water quality and on the ability of that body of water to support life
nuclear accidents
Three mile Island (U.S.) had a meltdown occured through one half of one reactor core. Chernobyl (Ukrain) was worst, with an explosion that destroyed the reactor and sent clouds of radioactive debris into the atmosphere. Recent example Fukushima, Japan wit
radioactive waste
Particles from a nuclear reaction that emit radiation; contact with such particles may be harmful or lethal to people and must therefore be safely stored for thousands of years.
Yucca Mountain
in Nevada as a permanent storage site for high-level radioactive wastes from commercially operated nuclear power plants
nuclear fusion
2 isotopes of light elements (H) forced together at high temperatures till they fuse to form a heavier nucleus. Happens in the Sun, very difficult to accomplish on Earth, prohibitively expensive.
hydroelectric
pertaining to the generation and distribution of electricity derived from the energy of falling water or any other hydraulic source
hydroelectric pros
renewable
electricity with no pollution
no mining
easy to make and cheap after dam is built
fish ladders
A stair-like structure that allows migrating fish to get around a dam.
issues with dams
Change rivers (Nile) , canyons, wildlife. Limited lifespan (50-75 years) because of silting (build up of sediment behind dam). Displacement of population from reservoir behind dam
hybrid vehicle
A vehicle that uses both an electric motor and internal combustion engine for propulsion. This type of vehicle gets
better gas mileage and has lower emissions than conventional
vehicles.
mass transit
solution to an urban problem; methods of moving large numbers of people. Ex: Buses, subway
passive solar
Features of ______ designs are adobe walls used for heat storage, windows on the south side of the house, summer cooling vents on the roof, and flagstone floor used for heat storage.
active solar
A method of capturing the sun's energy and distributing it using pumps and fans.
photovoltaic cell
solar energy cells, usually made from silicon, that collect solar rays to generate electricity
hydrogen fuel cells
combines hydrogen gas and oxygen gas fuel to produce electricity and water vapor. Fuel efficient, reduce fossil fuel use if hydrogen isn't extracted from one.
biomass
plant materials and animal waste used as fuel; wood, charcoal, animal waste
ethanol
a fuel made from corn and wheat that is used like gasoline but is a renewable resource
biodiesel
A diesel-equivalent, processed fuel derived from biological sources (such as vegetable oils), that can be used in unmodified diesel-engine vehicles.
wind turbine
A propeller driven by the wind and connected to a generator. The wind makes it turn the generator, which produces electricity.
wind energy pros
Clean emissions
Free energy source
Affordable power
tidal energy
energy produced by the rise and fall of ocean levels; used to generate electricity
geothermal
A resource uses the earths thermal energy to heat water and uses the steam to turn a generator to produce electric energy.
fracking
The pumping of water at high pressure to break apart rocks in order to release natural gas