Renewable Energy

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

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

Natural Gas or Electricity Water heater Electricity is produced at power plant via gas or coal and transferred via wire to your home Some energy is lost over the wire, …

Water Heater Tank Water is heated 365/24/7 Because heat is lost through the flue and the walls of the storage tank (this is called standby heat loss), energy is consumed even when no hot water is being used.

Water Heater Tankless The energy consumption of these units is generally lower since standby losses from the storage tank are eliminated. Demand water heaters with enough capacity to meet household needs are gas- or propane-fired. http://www.aceee.org/consumerguide/topwater.htm

Solar Energy Energy Efficiency 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 building’s heating or water heating needs. www.bio.miami.edu/beck/esc101/Chapter14 &15.ppt

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

Solar Domestic Hot Water (SDHW) An open circuit hot water system heats the domestic water directly on the roof of the building The water flows from the heat collector into the hot water tank to be used in the house Integration of solar energy conservation in homes can reduce energy consumption by 75-90%. www.iea-shc.org www.earlham.edu/~parkero/Seminar/ SOLAR%20AMERICA%5B1%5D.ppt

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

Inside the PV cell PV cells are made from silicon alloys PV module 1cm by 10cm cells 36 cells connected www.earlham.edu/~parkero/Seminar/ SOLAR%20AMERICA%5B1%5D.ppt

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

Solar Thermal Techniques Solar Two 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

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

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

History of Hydroelectric B.C. - Used by the Greeks to turn water wheels for grinding wheat into flour, more than 2,000 years ago 1775 - U.S. Army Corps of Engineers founded, with establishment of Chief Engineer for the Continental Army 1880 - Michigan's Grand Rapids Electric Light and Power Company, generating electricity by dynamo, belted to a water turbine at the Wolverine Chair Factory, lit up 16 brush-arc lamps. www.usd.edu/phys/courses/scst601/ hydroelectric/hydro.ppt

History of Hydroelectric By 1940 - 40% of electrical generation was hydropower Between 1921 and 1940 - conventional capacity in the U.S. tripled; almost tripled again between 1940 and 1980 Currently - about 10% of U.S. electricity comes from hydropower. www.usd.edu/phys/courses/scst601/ hydroelectric/hydro.ppt

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

Turbine Technologies Reaction fully immersed in fluid shape of blades produces rotation www.usd.edu/phys/courses/scst601/ hydroelectric/hydro.ppt

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

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

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

Rotary Windmill used to run water pumps, ~150,000 in U.S., provided means of pumping water. thousands of 2 – 3 kW units were installed in 30’s and 40’s REA and TVA phased out as they encouraged electrification www.usd.edu/phys/courses/scst601/wind_energy.ppt

Vertical Blades www.usd.edu/phys/courses/scst601/wind_energy.ppt

www.bio.miami.edu/beck/esc101/Chapter14 &15.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 North Dakota

Optimization Low Torque – Rapid Speed High Torque – Slow 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 don’t necessarily want a high speed pump because your holding tank has a limited capacity need to shut down with high wind speeds. tall towers are better Weibull distribution statistical plot optimize to average power from wind speed be careful of underestimating www.usd.edu/phys/courses/scst601/wind_energy.ppt

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

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

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

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

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

Geothermal Energy Efficiency Solar Energy Hydropower Wind Power Biomass Geothermal Sustainability www.bio.miami.edu/beck/esc101/Chapter14 &15.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 Direct-Use Power Plants shallow ground energy Direct-Use hot water can be piped to facilities Power Plants steam and hot water drive turbines dry steam plants flash steam plants binary cycle plants upper ten feet maintains a constant temp of between 50 and 60 degrees heat pump system consists of system of pipes buried in the ground, heat exchanger and ductwork winter: heat is extracted from the warmer ground (colder climate pipes may need to be deeper) summer: hot air is cooled via the ground summer heat removal can be used to heat water hot water can be used to heat buildings, grow plants in greenhouses, heat water for fish farming, pasteurize milk piped under sidewalks to melt snow (mostly used in western states) mile deep wells drilled into underground reservoirs tap steam and very hot water three t 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 includes problems with transport and storage of fossil fuels www.usd.edu/phys/courses/scst601/ geothermal/GeothermalEnergy.ppt

Flash Steam Power Plant Fluids above 200 degrees Celsius Fluid is sprayed into tank at lower pressure Fluid rapidly vaporizes Steam drives turbine www.usd.edu/phys/courses/scst601/ geothermal/GeothermalEnergy.ppt

Binary Cycle Power Plant Cooler water (below 200 degrees Celsius) Hot thermal fluid and a second fluid pass through heat exchanger www.usd.edu/phys/courses/scst601/ geothermal/GeothermalEnergy.ppt

Heat Mining Last week the Massachusetts Institute of Technology released a study concluding that heat mining could generate enough energy by 2050 to replace the coal-fired and nuclear power plants that are likely to be retired over the next several decades. Boston Globe Gareth Cook, Globe Staff  |  January 29, 2007 @ http://www.boston.com/news/globe/health_science/articles/2007/01/29/the_power_of_rocks/

At present the DHM project and drilling activities are financed by the Swiss Federal Office of Energy (SFOE), the canton of the city of Basel, the water and energy public utilities of Basel (IWB), a power company (Elektra Basel Land), and a private foundation (G.H. Endress) http://www.geothermie.de/iganews/no45/the_swiss_deep_heat.htm

Benefits Clean Energy Availability Homegrown Renewable 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

Location Hot geothermal fluid Low mineral and gas content Shallow aquifers Producing and reinjecting the fluid Private land Simplifies permit process Proximity to transmission lines 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 Dry hot rock heated by molten magma Drill into rock and circulate water www.usd.edu/phys/courses/scst601/ geothermal/GeothermalEnergy.ppt

Sustainability Energy Efficiency Solar Energy Hydropower Wind Power Biomass Geothermal Sustainability

Suggestions to make the transition to a more sustainable energy future. www.bio.miami.edu/beck/esc101/Chapter14 &15.ppt