Renewable Energy Chapters15 Living in the Environment , 12 th Edition, Miller

Renewable EnergyChapters15Living in the Environment, 12th Edition, Miller Advanced Placement Environmental Science

Energy Efficiency Solar Energy Hydropower Wind Power Biomass Geothermal Sustainability www.bio.miami.edu/beck/esc101/Chapter14&15.ppt

Energy Efficiency • Increasing energy efficiency of common devices has economic and environmental advantages • Reducing oil imports • Prolonging fossil fuel supplies • Reducing pollution and environmental degradation • Saving money • Buys time to develop new technology • Creating jobs

Efficiency of Some Common Devices Device Efficiency (%) • Dry-cell flashlight battery 90 • Home gas furnace 85 • Storage battery 70 • Home oil furnace 65 • Small electric motor 62 • Steam power plant 38 • Diesel engine 38 • High-intensity lamp 32 • Automobile engine 25 • Fluorescent lamp 22 • Incandescent lamp 4

Energy Efficiency percentage of energy input that does useful work in an energy conversion system

Ways to Improve Energy Efficiency • Between 1985 and 2001, the average fuel efficiency for new motor vehicles sold in the United States leveled off or declined • Fuel-efficient models account for only a tiny fraction of car sales • Hybrid-electric cars are now available and sales are expected to increase • Fuel-cell cars that burn hydrogen fuel will be available within a few years • Electric scooters and electric bicycles are short-range transportation alternatives

Energy use of various types of transportation www.bio.miami.edu/beck/esc101/Chapter14&15.ppt

Ways to Improve Energy Efficiency • Superinsulated house is more expensive than a conventional house, but energy savings pay back the extra cost • Strawbale houses have the additional advantage of using an annually renewable agricultural residue, thus slowing deforestation

Ways to Improve Energy Efficiency • Existing homes can be made more energy efficient • adding insulation • plugging leaks • installing energy-saving windows • wrapping water heaters • installing tankless models • buying energy-efficient appliances and lights

Energy Efficiency Solar Energy Hydropower Wind Power Biomass Geothermal Sustainability

Solar Energy • Buildings can be heated • passive solar heating system • active solar heating system • Solar thermal systems are new technologies that collect and transform solar energy into heat that can be used directly or converted to electricity • Photovoltaic cells convert solar energy directly into electricity

Suitability of Solar Usage best when more than 60% of daylight hours sunny www.bio.miami.edu/beck/esc101/Chapter14&15.ppt

Solar Heating Passive system: Absorbs & stores heat from the sun directly within a structure Active system: Collectors absorb solar energy, a pump supplies part of a buildings heating or water heating needs. www.bio.miami.edu/beck/esc101/Chapter14&15.ppt

www.bio.miami.edu/beck/esc101/Chapter14&15.ppt

Photovoltaic (Solar) Cells Provides electricity for buildings www.bio.miami.edu/beck/esc101/Chapter14&15.ppt

Solar Thermal Techniques SolarTwo www.earlham.edu/~parkero/Seminar/ SOLAR%20AMERICA%5B1%5D.ppt

Heliostats • Heliostats provide concentrated sunlight to the power tower • The reflecting mirrors follow the sun along its daily trajectory www.earlham.edu/~parkero/Seminar/ SOLAR%20AMERICA%5B1%5D.ppt

Power Tower • Sunlight from mirrors are reflected to fixed receiver in power tower • Fluid transfers the absorbed solar heat into the power block • Used to heat a steam generator Solar One www.earlham.edu/~parkero/Seminar/ SOLAR%20AMERICA%5B1%5D.ppt

Solar-Hydrogen Revolution • Splitting water can produce H2 gas • If scientists and engineers can learn how to use forms of solar energy to decompose water cheaply, they will set in motion a solar-hydrogen revolution • Hydrogen-powered fuel cells could power vehicles and appliances

Basically…… 2 H2O + 2 e- 2 OH- + H2 2 H2O O2 + 4 H+ + 4 e-

History of Hydroelectric • Currently - about 10% of U.S. electricity comes from hydropower. http://techalive.mtu.edu/meec/demo/HydroelectricDam. tml www.usd.edu/phys/courses/scst601/ hydroelectric/hydro.ppt

www.usd.edu/phys/courses/scst601/ hydroelectric/hydro.ppt

Tidal Power Plant www.bio.miami.edu/beck/esc101/Chapter14&15.ppt

Rotary Windmill www.usd.edu/phys/courses/scst601/wind_energy.ppt

Energy from Wind • Production of electricity and hydrogen gas by wind farms is expected to increase • Western Europe currently leads in the development of wind power • Land used for wind farms also can be used for ranching or crops and most profits stay in local communities

Optimization • Low Torque – Rapid Speed • good for electrical generation • High Torque – Slow Speed • good for pumping water • Small generator • low wind speeds • captures small amount of energy • Large generator • high wind speeds • may not turn at low speeds www.usd.edu/phys/courses/scst601/wind_energy.ppt

Source: American Wind Energy Association www.usd.edu/phys/courses/scst601/wind_energy.ppt

Energy from Biomass • In the developing world, most people heat homes and cook by burning wood or charcoal • Plant materials and animal wastes also can be converted into biofuels, • Biogas • Liquid ethanol • Liquid methanol • Urban wastes can be burned in incinerators to produce electricity and heat www.bio.miami.edu/beck/esc101/Chapter14&15.ppt

Types of Biomass Fuel www.bio.miami.edu/beck/esc101/Chapter14&15.ppt

Biorefinery • Fuels: • Ethanol • Renewable Diesel • Methanol • Hydrogen • Electricity • Heat • Products • Plastics • Foams • Solvents • Coatings • Chemical Intermediates • Phenolics • Adhesives • Fatty acids • Acetic Acid • Carbon black • Paints • Dyes, Pigments, and Ink • Detergents • Etc. Conversion Processes • Biomass • Feedstock • Trees • Forest Residues • Grasses • Agricultural Crops • Agricultural Residues • Animal Wastes • Municipal Solid Waste • Acid Hydrolysis/Fermentation • Enzymatic Fermentation • - Gas/liquid Fermentation • - Thermochemical Processes • - Gasification/Pyrolysis • - Combustion • - Co-firing www.sc.doe.gov/bes/besac/BESACGarman08-02-01.ppt

Geothermal Energy • Geothermal energy can be used to heat buildings and to produce electricity • Geothermal reservoirs can be depleted if heat is removed faster than natural processes renew it, but the potential supply is vast

Technology • Geothermal Heat Pumps • shallow ground energy • Direct-Use • hot water can be piped to facilities • Power Plants • steam and hot water drive turbines www.usd.edu/phys/courses/scst601/ geothermal/GeothermalEnergy.ppt

Dry Steam Power Plants • Hydrothermal fluids are primarily steam • Steam goes directly to turbine • No fossil fuels www.usd.edu/phys/courses/scst601/ geothermal/GeothermalEnergy.ppt

Benefits • Clean Energy • one sixth of carbon dioxide vs. natural gas • very little if any nitrous oxide or sulfur compounds • Availability • 24 hours a day, 365 days a year • Homegrown • Renewable www.usd.edu/phys/courses/scst601/ geothermal/GeothermalEnergy.ppt

Environmental Effects • Only emission is steam • Salts and dissolved minerals reinjected • Some sludge produced • Mineral extraction • Little Visual Impact • Small acreage, no fuel storage facilities www.usd.edu/phys/courses/scst601/ geothermal/GeothermalEnergy.ppt

www.eren.doe.gov/power/consumer/ rebasics_geothermal.html

Future • Only tiny fraction is currently used (U.S is the #1 user) • Dry hot rock heated by molten magma • Drill into rock and circulate water www.usd.edu/phys/courses/scst601/ geothermal/GeothermalEnergy.ppt

Energy Efficiency Solar Energy Hydropower Wind Power Biomass Geothermal Sustainability

Renewable Energy Chapters15 Living in the Environment , 12 th Edition, Miller