Energy Efficiency and Renewable Energy

Energy Efficiency and Renewable Energy G. Tyler Miller’s Living in the Environment 13th Edition Chapter 16 Dr. Richard Clements Chattanooga State Technical Community College

Key Concepts • Improving energy efficiency • Types and uses of solar energy • Types and uses of flowing water • Uses of wind energy • Types and uses of biomass • Use of hydrogen as a fuel • Use of geothermal energy • Decentralized power systems

The Importance of Improving Energy Efficiency • Net useful energy • Life cycle cost Least Efficient • Incandescent lights • Internal combustion engine • Nuclear power plants Fig. 16-2 p. 381

Efficiencies (fig. 16-4 p. 382)

Ways to Improve Energy Efficiency • Insulation • Elimination of air leaks • Air to air heat exchangers • Cogeneration • Efficient electric motors • High-efficiency lighting • Increasing fuel economy

Electric and Hybrid Cars Fig. 16-10 p. 365 • Rechargeable battery systems • Hybrid electric-internal combustion engine • Fuel cells • Emissions • Transition • technology

Using Solar Energy to Provide Heat • Passive solar heating -free • Active solar heating – low cost

Using Solar Energy to Provide High-Temperature Heat and Electricity Fig. 16-23 p. 398 Fig. 16-25 p. 400 • Solar thermal systems • Photovoltaic (PV) cells

Solar (photovoltaic cells) • Can be stored in batteries • New tech: thin panels, • nanochips in exterior paint • $1 per watt, or $.08 per kwh

Producing Electricity from Moving Water • Large Scale Hydropower – river is blocked by dam, • rushing water through turbines creates power • Negative: wildlife, silting, flooding, hab. destruction, • water loss (increased surface area to evaporate), • Small Scale Hydropower- waterwheel creates power, does not affect wildlife, 100 kW or less, requires specific flow • Tidal power plant – more predicatable, • Increase turbidity, decrease salinity, affect wildlife • Wave power plant-not commercially available.

Producing Electricity from Heat Stored in Water • Ocean thermal energy conversion (OTEC) • Heat engine between area of warm water and cooler water, as it passes • through, creates energy. $0.07 per kwh, not widely used yet • Saline solar ponds-due to salinity • heat trapped at bottom is used for thermal energy • for local buildings –rural and developing areas, • Evaporated freshwater must be replaced. • Low efficiency. • Freshwater solar ponds

Producing Electricity from Wind Fig. 16-28 p. 402 Fig. 16-29 p. 402

Wind • Advantages • Disadvantages

Producing Energy from Biomass Fig. 16-31 p. 404 • Biofuels • Biomass plantations • Crop residues • Animal manure • Biogas • Ethanol • Methanol

The Solar-Hydrogen Revolution Fig. 16-33 p. 386 • Extracting hydrogen efficiently • Storing hydrogen • Fuel cells

Geothermal Energy Fig. 16-36p. 409 • Geothermal reservoirs • Dry steam • Wet steam • Hot water • Molten rock • Hot dry-rock zones

Geothermal Reservoirs Fig. 16-37 p. 410

Entering the Age of Decentralized Micropower Fig. 16-40 p. 411 Fig. 16-39 p. 411 • Centralized power systems • Decentralized power systems • Micropower systems

Solutions: A Sustainable Energy Strategy Fig. 16-44 p. 414

Energy Efficiency and Renewable Energy