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What is Energy and Power?
Energy: the capacity to do work (the amount of work one system is doing on another)
Power: The amount of work done in a certain period of time
Two kinds of Energy!
1. Potential Energy: the mechanical energy that a body has by virtue of its position; stored energy
2. Kinetic Energy: Energy in motion
Conventional Energy Supplies
Fossil Fuels: coal, oil, gasNuclear Energy: fissionHydroelectric power: falling water
Energy Consumption
The United States uses a lot of energy—nearly a million dollars worth each minute, 24 hours a day, every day of the year. With less than five percent of the world’s population, we consume about one fourth of the world’s energy resources. We are not alone. People in Asia and Europe also use a large amount of energy.
The average American consumes six times more energy than the world average. Every time we fill up our cars or open our energy bills, we notice the cost of that energy.
Energy Conservation
Energy conservation is any behavior that results in the use of less energy.
Energy efficiency is the use of technology that requires less energy to perform the same function.
Which is more energy efficient?
What can you do to conserve energy?• Buy energy efficient appliances• Buy compact florescent light bulbs• Car pool, walk, ride a bike, use public transportation• Insulate your home• Use landscaping and architecture to warm and cool your home• Drive fuel efficient cars• Reduce, Reuse, Recycle
RECYCLING GUIDE
MATERIAL CAN be recycled CAN’T be recycled HOW TO DO IT
GLASSJars, bottlesClear, green, amber
Light bulbs, dishes, Pyrex, crystal
Rinse, remove lids.Separate by color
PAPER
Newspapers, boxesegg cartons, phone books,white office paper
Waxed, glued,plastic, or foil coated
Keep clean and dry
ALUMINUM
All aluminum—canspie pans, foil wrap, old windows, lawn furniture
Rinse and crush
STEEL Steel (tin) food Rinse and crush
PLASTICS All plastics Check with your recycler Rinse
Solar Energy
Photovoltaic energy is the conversion of sunlight into electricity through a photovoltaic (PVs) cell, commonly called a solar cell. A photovoltaic cell is a nonmechanical device usually made from silicon alloys.
Solar thermal power plants use the sun's rays to heat a fluid, from which heat transfer systems may be used to produce steam. The steam, in turn, is converted into mechanical energy in a turbine and into electricity from a conventional generator coupled to the turbine
Biomass EnergyBiomass is organic material made from plants and animals. Biomass contains stored energy from the sun. Plants absorb the sun's energy in a process called photosynthesis. The chemical energy in plants gets passed on to animals and people that eat them. Biomass is a renewable energy source because we can always grow more trees and crops, and waste will always exist. Some examples of biomass fuels are wood, crops, manure, and some garbage. When burned, the chemical energy in biomass is released as heat. If you have a fireplace, the wood you burn in it is a biomass fuel. Wood waste or garbage can be burned to produce steam for making electricity, or to provide heat to industries and homes.
Hydro Energy
Of the renewable energy sources that generate electricity, hydropower is the most often used. It accounted for 7 percent of total U.S. electricity generation and 75 percent of generation from renewables in 2004.
Tidal Energy
Tidal-power is the power achieved by capturing the energy contained in moving water mass due to tides. Two types of tidal energy can be extracted: kinetic energy of currents between ebbing and surging tides and potential energy from the difference in height (or head) between high and low tides. The former method - generating energy from tidal currents - is considered much more feasible today than building ocean-based dams or barrages, and many coastal sites worldwide are being examined for their suitability to produce tidal (current) energy.
Geothermal Energy
Volcanic energy cannot be harnessed (controlled and collected), but in a few places heat from the earth, called geothermal energy, can be collected. Usually, engineers try to collect this heat in the rare places where the Earth's crust has trapped steam and hot water. Here, they drill into the crust and allow the heat to escape, either as steam, or as very hot water. Pipes carry the hot water to a plant, where some of the steam is allowed to "flash," or separate from the water. That steam then turns a turbine - generator to make electricity.
Activities to complete on Alternative Energies
Energy Source Web Quest
20 Questions- web activity