Renewable energy


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Renewable energy

  1. 1. Energy Efficiency and Renewable Energy Chapter 18 Living in the Environment, 14 th edition, G. Tyler Miller
  2. 2. - What is energy efficiency? Miller says we waste about 43% of our energy unnecessarily. - Why worry about it? -Do you consider energy conservation and/or efficiency in your house? “ Tired of heating or cooling an empty house while you're away? In about an hour, you can be on your way to a more comfortable home. Depending on the model you select, you can program day and night temperatures and even a setting for every day of the week. You'll be more comfortable with your heating and cooling bill too.  Lowe's is happy to provide this information as a service to you.”
  3. 3. What’s a renewable energy source? What are some examples we can think of?
  4. 4. Making our homes & offices more efficient <ul><li>Sears tower consumes more energy in a day than a city of 150,000 people! (Miller) </li></ul><ul><li>Super insulation, plug leaks! </li></ul><ul><li>Use heat from the sun </li></ul><ul><li>Energy efficient windows </li></ul><ul><li>Landscaping, roof top gardens </li></ul><ul><li>Miller gives lots of other ideas in our text </li></ul><ul><li>The ING Bank in Netherlands, uses 92% </li></ul><ul><li>less energy than a conventional </li></ul><ul><li>building of its size </li></ul><ul><li> </li></ul>
  5. 5. How can we fuel our cars? <ul><li>Hybrids? </li></ul><ul><ul><li>Gasoline, diesel or natural gas & battery </li></ul></ul><ul><ul><li>30-300! mpg </li></ul></ul><ul><ul><li>Lower emissions </li></ul></ul><ul><li>Fuel Cells? </li></ul><ul><ul><li>H 2 will have to be generated </li></ul></ul><ul><ul><li>Efficient, 2H 2 + O 2 -> 2H 2 O </li></ul></ul><ul><ul><li>No moving parts, low maintenance </li></ul></ul><ul><ul><li>Get the costs down </li></ul></ul><ul><ul><li> </li></ul></ul><ul><li>E85 1) </li></ul>2)
  6. 6. More about ethanol… <ul><li>CH 3 CH 2 OH </li></ul><ul><li>Made from sugar, corn & other grains by fermentation </li></ul><ul><li>Have you heard of gasohol? (10-23%) </li></ul><ul><li> reduced emissions of CO 2 and CO </li></ul><ul><li> potentially renewable </li></ul><ul><li> net energy loss, higher cost </li></ul><ul><li> may compete with growing food </li></ul><ul><li> corrosive, harder to start car in cold weather </li></ul><ul><li>Also read about methanol CH 3 OH </li></ul><ul><li> </li></ul>
  7. 7. Renewable energy for heat and electricity <ul><li>Passive solar </li></ul><ul><li>Active solar </li></ul><ul><li>Solar thermal </li></ul><ul><li>Solar cells </li></ul><ul><li>Hydropower </li></ul><ul><li>Wind power </li></ul><ul><li>Biomass </li></ul><ul><li>Ethanol </li></ul><ul><li>Geothermal </li></ul><ul><li>Hydrogen </li></ul>
  8. 8. Renewable energy provides 16% of world’s energy in the world and 6% in the U.S. <ul><li>Miller says renewable resources haven’t received tax breaks, subsidies and R & D funding as fossil fuels and nuclear power have. </li></ul><ul><li>Prices we pay for fossil fuels & nuclear </li></ul><ul><li>don’t include environmental & health costs </li></ul>
  9. 9. Wind Energy! <ul><li>Mendota Hills Wind Farm </li></ul><ul><li>Global Wind energy </li></ul><ul><li> </li></ul><ul><li> </li></ul>
  10. 10. Solar energy…a myriad of possibilities <ul><li>Passive solar…absorbs and stores heat directly…use with good insulation </li></ul><ul><li>Need access to the sun </li></ul><ul><li>Need heat storage system </li></ul><ul><li>Back up system? </li></ul>
  11. 11. Active solar heating…. <ul><li>Uses heat absorbing fluids and pumps </li></ul><ul><li>Popular for heating water in homes </li></ul><ul><li>High set up costs, high maintenance and unappealing appearance </li></ul>
  12. 12. <ul><li>Solar thermal systems </li></ul><ul><ul><li>Collect and transform radiant energy from the sun into heat, used directly or converted to electricity. Used in desert areas. </li></ul></ul><ul><ul><li>Sunlight collected and focused on solar collectors. High temps produce steam to run turbines for electricity. </li></ul></ul><ul><ul><li>These need backup systems or storage, high cost of installation, high land use </li></ul></ul>
  13. 13. Photovoltaic cells (PV) <ul><li>You’ve seen them in calculators </li></ul><ul><li>Quick installation and can be moved; installed on roofs so little land use </li></ul><ul><li>Low environmental impact, no CO 2 </li></ul><ul><li>Long lasting, no moving parts </li></ul><ul><li> need backup systems </li></ul><ul><li> high costs currently </li></ul>
  14. 14. Hydropower <ul><li>Works based on water flowing from high to low elevations </li></ul><ul><li>Controlled by dams and reservoirs and used to spin turbines & produce electricity </li></ul><ul><li>20% of world’s electricity </li></ul><ul><li>Very efficient, low cost electricity </li></ul><ul><li>No air pollution or waste disposal </li></ul><ul><li>High construction costs </li></ul><ul><li>Alters animal habitat </li></ul><ul><li>Danger of collapse </li></ul><ul><li>Large dams high environmental impact </li></ul><ul><li> </li></ul>
  15. 15. Animation at this site! Go there!
  16. 16. Energy from biomass <ul><li>Plant & animal wastes burned to provide heat or electricity </li></ul><ul><li>Wood logs, pellets, wood chips, branches </li></ul><ul><li>Agricultural waste </li></ul><ul><li>Animal dung </li></ul><ul><li>“ Urban waste” = garbage; cardboard and paper, wood waste </li></ul><ul><li>Used for heating, cooking, industrial processes or to create steam to power turbines for electricity </li></ul><ul><li>Some argue that that the wastes should be left to feed livestock, recycle into the soil, prevent erosion </li></ul><ul><li>Biomass can also be converted to biogas (methane and CO 2 ) use bacteria and chemical processes to do this. </li></ul>
  17. 17.
  18. 18. Geothermal: energy from the earth <ul><li> </li></ul>
  19. 19. more on geothermal…. <ul><li>Low environmental impact; we’re tapping natural heat sources such as volcanic rock, geysers and hot springs. </li></ul><ul><li>Energy efficient and cost effective </li></ul><ul><li>1% of world’s electricity </li></ul><ul><li> Cost is high so source must be concentrated and accessible </li></ul><ul><li> Reservoirs can be depleted if heat is removed faster than resupplied . </li></ul><ul><li>Chevron graphic to see how geothermal works…. another animation </li></ul>
  20. 20. Hydrogen…a fuel of the future? <ul><li>2020-2030 </li></ul><ul><li>2H 2 + O 2 -> 2H 2 O </li></ul><ul><li>We’ll need to make the H 2 </li></ul><ul><li> high costs right now </li></ul><ul><li> no fuel distribution system in place </li></ul><ul><li>No green hou se gases </li></ul><ul><li>Safe, nontoxic, nonpollut ing, itself. </li></ul>
  21. 21. So what of the future? <ul><li>Wide variety of sources…no one answer </li></ul><ul><li> </li></ul><ul><li>What’s the energy policy in this country? </li></ul><ul><li>How does politics play into this? </li></ul><ul><li>Aging electrical grid system </li></ul><ul><li>What can YOU do? </li></ul><ul><li> </li></ul><ul><li> </li></ul>