1 / 60

Renewable Energy

Renewable Energy. Alternatives to Fossil Fuels and Nuclear Power. Alternative energy sources that are more or less continuously made available in a time framework useful to humans. Nonrenewable Energy.

awhitson
Télécharger la présentation

Renewable Energy

An Image/Link below is provided (as is) to download presentation Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author. Content is provided to you AS IS for your information and personal use only. Download presentation by click this link. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server. During download, if you can't get a presentation, the file might be deleted by the publisher.

E N D

Presentation Transcript

  1. Renewable Energy

  2. Alternatives to Fossil Fuels and Nuclear Power • Alternative energy sources that are more or less continuously made available in a time framework useful to humans

  3. Nonrenewable Energy • Energy sources that are dependent upon fuels or a resource that that may be used up much faster than it is replaced by natural processes

  4. Types of Renewable Energy • Solar • Water • Wind • Biomass • burning • conversion to liquid fuels • Geothermal • Solar-Hydrogen

  5. Current Sources of Energy

  6. Direct Solar Energy • Used to • Heat houses and buildings • Heat water • Create high temperature heat • Create electricity

  7. Solar Energy Usage

  8. Passive Solar Heating • Based on Architectural Design • Considers exposure direction, windows, building materials, eaves • Requires no energy to use • Absorbs/stores/slowly released

  9. Active Solar Heating • Uses mechanical power and pumps to circulate air • A heat absorbing fluid is heated by the sun and then transported into the structure • High cost, needs maintenance, unattractive

  10. Water Heating • Flat box with glass on top, black on the bottom, water tubes in middle • Hot water coming out of tubes is placed in top of tank • Cooler water from bottom is returned to collector

  11. High Temperature Heating • Solar Towers • many solar panels are used to focus solar energy for immediate, or later use

  12. High Temperature Heating • Solar Cookers - inexpensive • metal lined box and mirrors focus solar energy to cook food

  13. Solar Electricity • Photovoltaic cells or solar cells • When photons from sunlight hit a thin wafer of metal, a small electric current is produced

  14. Solar Electricity • Many cells must be linked together to produce usable energy • Mostly used in remote areas, calculators, watches

  15. Costs of Photovoltaic Cells

  16. Solar-Hydrogen Energy- Theory • Hydrogen gas can be used for energy in two ways: • burned directly - since no carbon, it burns cleanly, producing water • combined with oxygen gas to produce water (fuel cells)

  17. Solar-Hydrogen Energy • Problem: • Hydrogen gas is very rare in the environment • H2 gas is costly to make through chemical reactions

  18. Solar-Hydrogen Energy • Solution: • H2 and O2 can be produced easily by running a current through water - electrolysis • Solar cells can be used to create electricity to fuel electrolysis H2 gas

  19. Salt Water Solar Ponds • Heat accumulates in bottom layer • Layer is pumped out and used for heating or electricity

  20. Fresh Water Solar Ponds • Holes are dug and lined with black. • Water heats up, but heat is prevented from escaping • Both methods are cheap, do not pollute • Don’t require expensive storage: Save energy.

  21. Indirect Solar Energy • Methods of creating electricity • Biomass Energy • Wind Energy • Hydropower • OTEC • Waves & Tides

  22. What is BIOMASS? • Organic matter produced by photosynthetic producers • Total dry weight of all living organisms at each trophic level in a food web • Dry weight of all organic matter in an ecosystem; plant materials and animal wastes used as fuel.

  23. METHODS OF USING BIOMASS ENERGY Method #1 Burning Biomass to create heat Method #2 Gaseous Biofuels Liquid Biofuels

  24. Method #1 - Burning • Dung, Reeds, Wood • Biomass must not be removed faster than it can be replaced

  25. Biomass - Burning • Primarily used in developing countries • Trash can also be burned • Efficient when harvested locally • Burning dung takes nutrients from fields

  26. METHOD #2 • Convert solid biomass into gas and liquid biofuels • BIOGAS (60% methane) • Ethanol • distilled and fermented grains • Methanol • high cost: produced from sewage sludge, wood, wood wastes, agricultural wastes, garbage & coal

  27. Biogas - Landfills • Puente Hills Landfill • Uses local solid waste as source

  28. Landfill Mound • “Capped” landfill mound • Methane bubble trapped beneath

  29. Gas Extraction Wells • Gas Extraction wells on top • Reclaimed as a nature center • Return of wildlife • Parks for recreation

  30. Gas Wells • Gas pressure, temp constantly monitored • Automatic shutdown if necessary

  31. Burn-Off Pipe • Burn-off for noxious materials • Goes out regularly; has to be relit or BOOM! Someone on constant duty

  32. Gas Compressor • Concentrates methane

  33. Turbine for Electricity • Gas mixture burned • Generates steam; turns turbine

  34. Ethanol and Methanol • Excess grain stocks can be fermented by bacteria to produce these fuels which can then be burned as fuel • Burning both of these fuels still produces CO2

More Related