Unit Four

1. Unit Four “Renewable Energy Alternatives – Conventional & New Methods”

2. Recap from Chapter 18 • CO2 is a greenhouse gas that exist naturally in the atmosphere • CO2 is also a chemical released as a byproduct of electricity generation (coal) and the use of internal combustion engines (gas in cars) • Too much CO2 may be causing global warming • Coal and oil reserves are still present, and will be available for at least 20 or more years – Will society keep using them at the same rate until they are totally depleted?

3. Current Energy Usage • Fossil Fuels account for 80% of the world’s supply of primary energy • http://www.eia.gov/totalenergy/data/annual/pecss_diagram.cfm U.S.A. Energy Breakdown

4. Conventional Alternatives to Fossil Fuels • There are three alternatives that are not considered new technology, and as a result, are called “conventional”: • Nuclear • Biomass • Hydroelectric

5. Nuclear Power Benefits • A fraction of the amount of nuclear fuel is needed compared to coal to generate the same amount of electricity – it is a more efficient fuel source • If there are good safety measures in place, a meltdown is highly unlikely – look to France for examples • There is no pollution emitted from nuclear power facilities

6. Nuclear Power Drawbacks • It is nonrenewable as there is only a finite amount of “fuel” available within the earth • There has been only one major incident involving nuclear power – Chernobyl in 1986 • The spent fuel rods must be stored somewhere safe (no moisture, secure from terrorists) for hundreds of years • Public perception is the biggest problem in reference to establishing more nuclear power facilities

7. Types of Nuclear Power • Fission – the splitting of atomic nuclei thereby releasing energy (heat and radiation) • Breeder Nuclear Fission is the most efficient form of nuclear power by using less fuel, producing more power, and also much less waste • Fusion – combining two small atoms into a larger one thereby releasing large amounts of energy (heat and radiation) • The Sun: Hydrogen atoms fuse to form Helium atoms, and by doing so, release massive amounts of energy • This process requires very high temperatures, and therefore is not used currently to generate electricity

8. Nuclear Fission

9. Nuclear Fusion

10. Biomass Energy • Any organic material that can be burned to generate heat or fuel an internal combustion engine • Biopower – heat used in power plants • Wood • Manure • Biofuels – fuels that power automobiles • Crops • Crop Residues (corn stalks – ethanol)

11. Biofuel Benefits • It is a renewable source of fuel and does not require extraction from the earth • It reduces car emissions • The “Big Three” car makers in the U.S.A. manufacture cars that run on a mix of 85% ethanol and 15% gasoline: E-85 fuel • In Brazil, half of all new cars are flex-fuel cars • Many other nations now have cars that can use ethanol as fuel

12. Biofuel Drawbacks • Growing crops specifically for fuel leads to monocultures, which leads to loss of nutrients from the soil and eventual desertification • Biofuels lead to higher costs for other consumer products because corn is a feed for cows and other farm animals

13. Biomass Benefits • It is a renewable source of energy • It is fairly cheap and does not require extraction from the earth • It releases no net carbon into the atmosphere; net carbon flux to the atmosphere is reduced • Biomass is fairly equally distributed across the globe • More energy efficient than fossil fuels • Reduces pollution emissions (sulfur and nitrogen) that are released in coal fired power plants

14. Biomass Drawbacks • Harvesting wood at a rapid rate leads to deforestation, soil erosion, desertification, and lastly, loss of biodiversity • Burning manure can cause noxious odors that can negatively affect the quality of life and possible health of citizens nearby

15. Hydroelectric Power • Two main types of Hydroelectric Power Plants • Reservoir/Storage – Lake Meade and the Hoover Dam • “Run of River” – Niagara Falls

16. Reservoir/Storage

17. “Run of River”

18. Hydroelectric Power Benefits • It is a renewable energy source • It does not generate any pollution • “Run of River” has minimal impact on the surrounding ecosystems

19. Hydroelectric Power Drawbacks • Can only build these power plants where water is plentiful (near large lakes or rivers) • Reservoir/Storage technique has a substantial negative impact on surrounding ecosystems

20. New Renewable Energy Reason for “New” moniker 1) They are not yet used on a wide scale as that of fossil fuels and conventional energy alternatives 2) They are harnessed using technology that is still being developed and refined 3) They will most likely come to play a larger role in our global energy production in the future

21. New Renewable Energy Reason for “New” moniker 1) They are not yet used on a wide scale as that of fossil fuels and conventional energy alternatives 2) They are harnessed using technology that is still being developed and refined 3) They will most likely come to play a larger role in our global energy production in the future

22. New Renewable Energy The benefits of all new renewable energy forms are as follows: 1) emits no pollution 2) requires no mineral extraction/ altering of the landscape 3) infinite supply 4) reduces the U.S.A. dependence on foreign sources of energy 5) energy source is free of charge (do not pay to use the energy from the sun or wind etc.)

23. New Renewable Energy Examples Solar Wind Geothermal Ocean Water 0.2% 2.3% 5.6% 0% ** U.S. total primary energy from new renewable sources in 2004

24. Solar Energy Passive Solar – buildings are designed and constructed to maximize direct absorption of sunlight in winter, and to keep the interior cool in summer Example: Student Union at UCF

25. Solar Energy Active Solar – utilization of components and devices that focus, move, or store solar energy Example: Solar Array https://solarems.net/kiosks/157

26. Passive Solar Specifics Focuses on designing the most energy efficient edifice in reference to building materials used and placement of windows and overhangs If constructed properly, a passive solar building will save money on energy bills by keeping it cool in the summer and warm in the winter It does so by using the energy from the sun and the building materials in the most effective manner

27. Passive Solar Specifics Electricity providers can assist with energy audits to enable citizens to become more passively solar efficient UCF Green Roof is an example of passive solar techniques in action (with a twist) http://www.progress-energy.com/shared/stw/main.html http://www.fpl.com/residential/electric/highbill.shtml

28. Active Solar Specifics Energy to Electricity Steps 1) Photovoltaic cells collect and convert the sun’s radiant energy to electricity (moving electrons) 2) electricity is stored in batteries for use when the sun is not available (night) *** An Array is made of a Panel, which is made of many PV Cells

29. Current Solar Use Used on a very limited basis mainly due to a lack of investment Federal funding for Solar Power has been erratic as a response to the availability and cost of oil As the cost of PV Cells and batteries decline, the amount of electricity generated as a result of the sun’s radiant energy will increase

30. The future of Solar There are only two major disadvantages to solar power: 1) some regions are not conducive 2) initial set up cost *** The future looks “bright” for solar power

31. Wind Energy Wind energy is available due to the action of the sun’s differential heating of air masses causing the movement of those air masses (wind) Wind Turbines are used to generate electricity – they convert the kinetic energy of wind into electrical energy

32. The Process of Wind Energy 1) Winds turn a blade 2) The blade causes the shaft to spin 3) the shaft enables the magnets and copper wire to move passed each other thereby generating electricity

33. Current Wind Use The U.S.A. (16%) ranks second to Germany in it’s total wind capacity California and Texas account for 2/3 of the wind power generated in the U.S.A. Globally, only a very small portion of this resource is being used

34. The Future of Wind Meteorological evidence suggest that wind power could supply the entire electrical needs of the U.S.A. Off shore sites may be an excellent place to build wind farms as the wind speed is fairly high and constant – need to address initial cost of set up, ongoing maintenance, and protection from strong wave action

35. The Future of Wind Only three disadvantages: 1) intermittence of wind 2) transmission of electricity from wind farm to urban areas 3) NIMBY phenomenon http://www.pickensplan.com/index.php?bcpid1842760405?bclid=1842745810&bctid=1653634930&page=white

36. Geothermal Energy This form of quasi-renewable energy (aquifer levels and geothermal activity) does not come from the sun Magma is expelled through fissures in the tectonic plates within the earth’s crust and heats water in aquifers throughout the world Magma is very hot and this energy can be used to heat water into steam that turns a turbine thereby generating electricity Can harness this energy at the surface via Geysers, but usually electricity is generated from water heated within aquifers located in the Earth’s crust

37. The Process of Geothermal Energy 1) Hot water from the Aquifer (close to the fissure) is pumped to the surface 2) heat is transferred to water in the closed turbine section 3) the heated water in the closed turbine section turns into steam 4) the force of the steam turns the turbine which generates electricity in the generator through the interaction of copper wire and magnets

38. Current Geothermal Use Currently Japan, China, and the U.S.A. lead the world in use of geothermal power Northern California has several geothermal facilities which operate due to the presence of geysers Iceland has high geothermal activity and the country is taking advantage of this resource to generate electricity

39. The Future of Geothermal Very little electricity is generated worldwide from geothermal activity There is much room for growth of this form of energy for use in electrical generation http://geothermal.marin.org/geomap_1.html

40. Ocean Water Energy Similar to the Hydroelectric process in that the motion of water (kinetic energy) is used to turn a turbine to generate electricity Main disadvantage is the remoteness of wave/tidal farms to urban centers Two types of ocean water energy: 1) Wave Motion (air turns turbine) 2) Tidal Motion (water turns turbine)

41. Tidal Energy

42. Wave Energy

43. Future of Ocean Water Energy Highly underutilized resource currently Waters off the coast of Scotland have great potential for tidal energy use The “Aqua Buoy” may be the future of wave energy http://www.youtube.com/watch?v=A5AY71sFeUw

44. Hydrogen as a Renewable Energy Source This technology is being developed mainly to address the transportation needs of the planet The energy source, water, is renewable The exhaust from this type of engine is water vapor This is a very promising technology in reference to sustainable automotive travel http://www.youtube.com/watch?v=oy8dzOB-Ykg