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Energy Efficiency


									Energy Efficiency

                  Energy Efficiency
• Measure of useful energy
  produced compared to energy
• Also known as the total net
  energy yield
    – Ex: nuclear power plants
      produce a lot of energy from
      small amount of fuel but the
      energy put into mining,
      smelting, etc is greater so it is
      hard to “break-even”
• Light given off from light bulb is
  useful but heat given off is
    – Incandescent bulb (regular
      bulb) is 5% efficient
    – Fluorescent bulb is 22%
Energy Efficiency in the Home
      Compact Fluorescent Light (CFL)
           Bulbs & Your Home
• 1CFL is equal to 13 regular bulbs
• CFL’s are a little more expensive
  but you save money on bulbs &
  electric bill later
    – 1 Sylvania CFL- $6.98
    – 24 Sylvania regulars- $9.98
• CFL’s use lower wattage to get
  same amount of light
    – 13 watt CFL can give off as much
      light as 60 watt regular bulb using
      ¼ of electricity
    – By replacing 25% of your regular
      with CFL, you can save 50% on
      energy bill.
• Incandescents & Halogens give off
  more heat than CFL’s
    – In summer this can cause you to
      use your air conditioning more.
• Same quality of light

                                                            23W Compact
                      Bulb Type 100W Incandescent

                 Purchase Price               $0.75                $11.00
                Life of the Bulb          750 hours          10,000 hours

   Number of Hours Burned per
                                            4 hours               4 hours

                                     About 6 over 3
      Number of Bulbs Needed                              1 over 6.8 years

            Total Cost of Bulbs               $4.50                $11.00
              Lumens Produced                 1,690                    1,500

        Total Cost of Electricity
                                             $35.04                    $8.06
        (8 cents/kilowatt-hour)

   Your Total Cost over 3 years              $39.54                $19.06

    Total Savings over three years with the Compact

Source: U.S. Department of Energy, Energy Information Administration
     CFLs and the environment
• 20 watt CFL used instead
  of 75 watt incandescent
  bulb saves 550 kWh of
• This saves 500 pounds of
  coal which keeps 1300
  pounds of carbon dioxide
  emissions and 20 pounds
  of sulfur emissions out of
  the air.
  Energy Star Products
• Joint program of the U.S.
  EPA and the U.S. DOE
• Designed to protect the
  environment thru energy-
  efficient products &
• In 2005, programs
  coordinated thru Energy
  star saved $12 billion in
  utility bills and avoided
  greenhouse gas
  emissions equivalent to
  23 million cars.
Energy Efficiency & Cars
             State Energy Program
Energy conservation Act (1975)
• Set up Strategic Petroleum Reserve so we can stockpile crude oil
• Established programs to foster energy conservation in federal buildings and major
   U.S. industries
• Provide states with funding for renewable energy and energy efficiency projects
• Corporate Average Fuel Economy (CAFE) standards set. See next slide about CAFE

Energy Policy Act (1992)
• States play crucial role in regulating local energy industries
• Expanded states role in policy development & technology deployment
• Allowed “revolving” funds for renewable & energy efficient projects

Energy Funding Allocation- how is the money distributed by Department of Energy
• 1/3 distributed equally
• 1/3 based on population
• 1/3 based on energy consumption
• 20% must be provided by state
                     CAFE standards
•   Corporate Average Fuel Economy
•   Average fuel economy for a manufacturer’s fleet of cars that have a gross
    vehicle weight rating (GVWR) of 8,500 lbs or less. Expressed in miles per
    gallon (mpg). Tested by company or EPA.
•   Passenger cars standard- 27.5 mpg
•   Light truck standard- 22.2 mpg
•   SUV’s, Pickup trucks, and large vans are exempt
•   Achieved thru better engine design, efficiency & weight reductions
•   If car/truck does not meet standards, may be penalized.
     – Charged $5.50 per 1/10th of a mpg that does not meet target rate
•   Can earn credits during “passing” years that can be used during “non
    passing” years to help them “pass” and not have to pay so much in penalty
•   From 1975-1985 fuel efficiency increased. Since 1985, fuel efficiency has
    leveled off.
     Gas Cars vs. Electric Cars vs.
             Hybrid cars
• 1 gallon of gas weighs 6 lbs
  and when burned releases 20
  lbs of CO2!
• Electric cars produce no
  emissions (from the car) but
  must be recharged between
  uses (every 50-100 miles).
  This slow recharging process
  draws a lot of electricity so you
  still have energy generated
  from coal power plants which
  still causes pollution.
• Hybrid cars- increase mileage
  of gas (reduce emissions) and
  do not have to be recharged.
   Hybrid Cars
• Gasoline-electric engine
• High efficiency, lowest
• An electric motor run by
  batteries supplements gas
  engine so uses less gasoline.
• Can get 40-50 miles per gallon
  in many hybrid cars
• Cons- higher initial cost
• Pros-
   – lower operating costs later on
   – Economic incentive: Can earn
     tax credits of up to $3,000
            Types of Hybrids
• Parallel- fuel tank that supplies gasoline to
  engine & set of batteries that supplies power to
  electric motor; both gas & electric supply power
  to wheels; shuts down gas at a light &
  accelerates using electric (Toyota, Lexus, Ford)
• Series- gas engine turns generator, which
  charges the batteries &/or powers an electric
  motor; gas engine is not used to make car go
  (General Motors)
• Plug-in- added battery; plugged into 120 volt
  outlet to charge (60 miles per charge); when run
  out of charge, switches to fuel tank
              Hydrogen Fuel Cells
• Works like a battery
    – Cathode & anode separated
      by membrane
    – Oxygen passes over one,
      hydrogen over the other
    – Hydrogen reacts with anode &
      is converted to negatively
      charged electrons & positively
      charged hydrogen ions.
    – Electrons flow out of cell to be
      used as electrical energy.
    – Hydrogen ions move thru the
      electrolyte membrane to the
      cathode where they combine
      with oxygen to make water

• Only have to refill the hydrogen
  to keep reaction going.
How a Hydrogen Fuel Cell Works
          Hydrogen Fuel Cells
• Pros                           • Cons
  – Waste is pure water            – Takes energy to produce
  – Ocean or freshwater can          hydrogen from either water
    be used to obtain hydrogen       or methane
  – Does not destroy wildlife      – Changing from fossil fuels
    habitats                         to hydrogen fuel would be
  – Causes minimal                   very expensive & cost
    environmental impact             people their jobs
  – Energy used to create          – Hydrogen gas is explosive
    hydrogen could come from       – Currently difficult to store
    solar power                      hydrogen gas for cars
  – Hydrogen easily
    transported thru pipes
  – Can be stored in
    compounds to make it safe
    to handle
What can be done to help?
            Negawatts program
• Programs sponsored by
  energy companies
• Easier to finance education &
  conservation projects than
  build new coal power plants
• “demand avoidance”
• Conservation projects (public
  education, home improvement
  loans, efficiency labels,
  reduced taxes on energy
  saving appliances) cost about
  $350 per kWh saved
• New nuclear power plants cost
  $3000-$8000 per kW of
  installed capacity
• New coal power plants with
  latest air pollution control
  equipment is $1000 kW
                  What can you do?
•   Drive less; make fewer trips
•   Use public transportation, walk or ride bike
•   Carpool; drive smaller car; reduce speeds
•   Use stairs instead of elevator
•   Insulate home or add more insulation. Higher the “R” value on insulation,
    the better it is
•   Turn thermostats down in winter & up in spring
•   Weather strip or caulk around windows & doors
•   Add plastic sheets to windows
•   Open blinds during day and close at night trapping heat stored during day
•   Turn off lights, TVs, computers when not in use; use compact fluorescent
•   Stop faucet leaks- especially hot water
•   Use low flow shower heads, take shorter, cooler showers
•   Recycle glass, metals, paper; compost organic matter
•   Eat locally grown food in season- reduces transportation cost & use of gas
•   Buy locally made, long-lasting materials
          Interesting Links

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