Energy Efficiency and Renewable Energy Chapter 16

16-1 Why Is Energy Efficiency an Important Energy Resource?  Concept 16-1 We could save as much as 43% of all the energy we use by improving energy efficiency.

We Waste Huge Amounts of Energy  Energy conservation A decrease in energy use as a result of a decrease in the amount of wasted energy – “Use less”  Energy efficiency The measure of work we can get out of a unit of energy we use – “Use it better”  Four widely used devices waste large amounts of energy: Incandescent light bulb: 95% lost as heat Internal combustion engine: 94% of the energy from fuel wasted Nuclear power plant: 92% of energy is wasted through nuclear fuel and energy needed for waste management Coal-burning power plant: 75-80% of the energy released by burning coal is lost

Flow of Commercial Energy through the U.S. Economy  84% of all commercial energy used in the U.S. is wasted.  41% wasted due to the 2 nd law of thermodynamics.  Only 9% of the total energy put into the U.S. economy results in useful energy.

Advantages of Reducing Unnecessary Energy Waste

16-2 How Can We Cut Energy Waste?  Concept 16-2 We have a variety of technologies for sharply increasing the energy efficiency of industrial operations, motor vehicles, and buildings.

 Industry accounts for 38% of U.S. energy consumption. It can save energy and money by: Produce both heat and electricity from one energy source (cogeneration or combined heat and power, CHP) Use more energy-efficient electric motors Recycle materials Switch from low-efficiency incandescent lighting to higher- efficiency compact fluorescent (CFL) and LED lighting Update the old/wasteful electrical grid system (how electricity is transmitted from the power plant to the consumer) Utility companies promote use of energy Instead, should promote conservation We Can Save Energy and Money in Industry

We Can Save Energy and Money in Transportation  Transportation accounts for 2/3 of U.S. oil demand and is a major source of air pollution.  We can save energy in transportation by increasing fuel efficiency and making vehicles from lighter and stronger materials.  Corporate Average Fuel Economy (CAFE) standards The average fuel economy, in miles per gallon (mpg), of a manufacturer’s fleet of passenger cars and/or light trucks  Fuel-efficient cars are on the market  Tax breaks for buying fuel-efficient cars

Average Fuel Economy of New Vehicles Sold in the U.S. and Other Countries  CAFE standards did not increased from 1985 to  In 2009, the Obama administration increased the standards to 35.5 MPG by  In 2012, the Obama administration increased the standards again to 54.5 by This represents the doubling of the original CAFE standards

 Hybrid vehicles have two types of engines working together to achieve higher gas mileage ( 15-70% more ) and lower engine exhaust emissions: A standard gas powered engine An electric motor assist powered by a rechargeable nickel-metal hydride (NiMH) battery pack  Gasoline-electric hybrid car Mostly gas…some electric  Plug-in hybrid electric vehicle Mostly electric…some gas  Electric vehicle (EV’s) ALL electric More Energy-Efficient Vehicles Are on the Way

Solutions: A Hybrid-Gasoline-Electric Engine Car and a Plug-in Hybrid Car

 Hybrid cars accounted for 3.5% cars on the road in Up from than 1% in 2007  Typically cost $3-4,000 more than non-hybrid models.  Plug-in hybrids can get twice the mileage of gasoline- electric hybrid cars, but… How is the electricity generated? Electricity from coal or nuclear power plants = JUST AS BAD Electricity produced by wind or solar energy = GOOD  Analysts estimate that hybrid cars could make up as much as 20% of the car market by the year The boost in sales will be pushed by consumer demands and possible government regulations on CO 2 emissions. More Energy-Efficient Vehicles Are on the Way

Science Focus: The Search for Better Batteries  Current obstacles to hybrid or electric vehicles: Storage capacity of battery Currently about 100 mile range Charging time 8 hours for a Nissan Leaf (available NOW) 3 hours for a Ford Focus EV (available in 2013) Use of rare earth metals for battery construction

We Can Design Buildings That Save Energy and Money  Green architecture Makes use of passive solar heating, natural lighting, natural ventilation, rain water collection, cogeneration of heat/electricity, geothermal heat pumps, and recycled building materials  Living or green roofs  Superinsulation  U.S. Green Building Council’s Leadership in Energy and Environmental Design (LEED) Graded on 100 possible points: Certified points Silver points Gold points Platinum - 80 points up

We Can Save Energy and Money in Existing Buildings  Insulate and plug leaks  Use energy-efficient windows  Stop other heating and cooling losses  Heat houses more efficiently  Heat water more efficiently  Use energy-efficient appliances  Use energy-efficient lighting  About 1/3 of the heated air in typical U.S. homes and buildings escapes through closed windows, holes, and cracks.

Individuals Matter: Ways in Which You Can Save Money Where You Live

 Low-priced fossil fuels and few government tax breaks or other financial incentives for saving energy promote energy waste. Why Are We Still Wasting So Much Energy?

 A variety of renewable-energy resources are available but their use has been hindered by a lack of government support (subsides) compared to nonrenewable fossil fuels and nuclear power. Direct solar Moving water Wind Geothermal We Can Use Renewable Energy in Place of Nonrenewable Energy Sources