| 6531281563 | solar cells | -Also called photovoltaics
-Thin pieces of purified silicon with small amounts of metals function as semi conductors
-When struck by sunlight, they emit electrons that flow to create an electrical current
-Each cell produces a small amount of power and is connected with batteries that store the energy | | 0 |
| 6531281564 | wind farms | Large numbers of windmills concentrated in a single area; usually owned by a utility or large-scale energy producer. | | 1 |
| 6531281565 | fuel cells | an electrochemical cell that uses replenishable substances such as hydrogen or oxygen or water to produce electricity | | 2 |
| 6531281567 | energy conservation | reducing or eliminating the unnecessary waste of energy | | 3 |
| 6531281568 | energy efficiency | the percentage of energy put into a system that does useful work | | 4 |
| 6531281569 | incandescent light bulb | use only 5% of the electricity it draws to produce light, with the other 95% wasted as heat; heat bulb | | 5 |
| 6531281571 | internal combustion engine | a motor vehicle with this type of engine wastes 94% of the energy in its fuel | | 6 |
| 6531281572 | nuclear power plant | a thermal power station in which the heat source is a nuclear reactor. | | 7 |
| 6531281573 | passive solar heating system | a system that uses the sun's energy without requiring mechanical devices (pumps or fans) to distribute the collected heat | | 8 |
| 6531281574 | active solar heating system | absorbs energy from the sun by pumping a heat-absorbing fluid through special collectors or racks | | 9 |
| 6531281576 | solar thermal plant | sunlight is collected and focused on oil-filled pipes running through the middle of a large area of curved solar collectors. | | 10 |
| 6531281577 | photovoltaic (PV) cells | cells, usually made of specially-treated silicon, that transfer solar energy from the sun to electrical energy | | 11 |
| 6531281578 | hydropower | -Water flowing from higher to lower elevations controlled by streams and reservoirs
-Flows through pipes to spin turbines, producing electricity
-United States is the largest producer (50% in West coast) | | 12 |
| 6531281581 | ocean thermal energy conversion (OTEC) | Electricity generation by making use of the temperature difference (as much as 20°C, or 68°F, in the tropics) between the top and bottom layers of the ocean to convert a fluid to vapor, which in turn powers a turbine generator. Low efficiency and saltwater corrosion are two current technical problems with the implementation of OTEC. | | 13 |
| 6531281582 | wind | air flows that are set up by the difference in solar heating of the earth between the equator and the poles, together with the earth's rotation | | 14 |
| 6531281583 | biomass | -Organic plant materials and animals wastes burned into fuel or converted into biofuels
-Make up 95% of energy in developing countries
-Most plentiful fuel source, renewable as long as it is not used faster than its produced
-Energy crops are cultivated to produce bioenergy | | 15 |
| 6531281584 | biofuels | fuels, such as ethanol or methanol, that are created from the fermentation of plants or plant products | | 16 |
| 6531281585 | fuelwood crisis | occurs when people are forced to meet their fuel needs by harvesting wood faster than it can be replenished | | 17 |
| 6531281586 | biomass plantations | area where large numbers of fast-growing trees, shrubs, perennial grasses, and water hyacinths are planted, harvested and burned to produce solid biomass fuel | | 18 |
| 6531281587 | ethanol | production of two useful forms of energy, such as high-temperature heat or steam and electricity, from the same fuel source | | 19 |
| 6531281588 | strawbale houses | super-insulated houses with walls made by stacking compacted bales of low-cost straw (an agricultural waste) and then covering the bales on the outside and inside with plaster or adobe | | 20 |
| 6531281589 | superinsulated house | Heavily insulated so direct sun, appliances, and human bodies can warm it
-Air-to-air heat exchanger prevents indoor pollution
-Costs five percent more, but the cost is later paid back | | 21 |
| 6531281592 | Corporate Average Fuel Economy (CAFE) | CAFE standards enacted into law in 1975, established fuel efficiency standards for passenger cars and light trucks. The fuel economy ratings for a manufacturer's entire line of passenger cars must currently average at least 27.5 mpg for the manufacturer to comply with the standard. 35 by 2020. | | 22 |
| 6531281594 | net energy | the net energy efficiency of a system used to heat your house is determined by the efficiency of each step in the energy conversion for the entire system | | 23 |
| 6531281595 | cogeneration | production of two useful forms of energy, such as high-temperature heat or steam and electricity, from the same fuel source | | 24 |
| 6531281596 | coal-burning power plant | heat produced by coal in a furnace boils water to produce steam, the steam spins a turbine to produce electricity, the steam is cooled and condensed, the steam returns to the furnace for reuse. 2/3 of the energy released by burning coal ends up as waste heat in the environment | | 25 |
| 6531281597 | switch grass | A promising candidate for producing bioethanol. A tall grass native to North American prairies that grows faster and needs less fertilizer than corn. It can also be grown on land unfit for crops and helps remove CO2 from the atmosphere | | 26 |
| 6531281598 | biodiesel | -Combines alcohol with vegetable oil extracted from renewable resources
-European Union produces/uses 95% of the world's biodiesel
-In the United States, soybeans supply 10% of diesel fuel needs
-Largest producers include Brazil, Malaysia, and Indonesia | | 27 |
| 6531281599 | methanol | alcohol containing one carbon atom per molecule, generally made from natural gas, with about half the energy density of gasoline, also known as 'wood alcohol' | | 28 |
| 6531281600 | geothermal energy | energy derived from the heat in the interior of the earth | | 29 |
| 6531281606 | gasohol | fuel blend of 10% ethanol and 90% gasoline | | 30 |
