A Sustainable Energy Future
Renewable, Reliable,
Clean, Efficient
Solar Energy Renewable Energy Source – THE
Found every where at least part of the year.
Four (4) Types: Passive Solar Heating Active Solar Water Heating Solar Cells aka Photovoltaic cells Solar Thermal Systems
Passive Solar HeatingHow it works:
Build your home facing south.Large, double pane windows.Thick walls & insulation on north side.Concrete, adobe or stone construction.Venting for hot air out during summer.Drapes in winter to keep heat in at night.Deciduous trees planted on south side
Block sunlight in summerAllow sunlight in winter
Passive Solar Heating
Passive Solar Heating
ADVANTAGES
Free energy
Renewable
Clean
Safe
DISADVANTAGES
Unattractive
Is there enough available sunlight in all areas?
Construction costs
Requires backup heat source
Solar Water Heating (add this info on your chart underneath Passive Solar)
How it works:
“Solar Collectors” on roof
Pipes with water or anti-freeze are coiled through box on roof.
Heated water transferred to basement.
Heat exchanged to fresh water; water pumped back to roof to be reheated.
Solar Water Heating
Solar Water Heating
ADVANTAGES
Free energy
Renewable
Clean
Safe
DISADVANTAGES
Unattractive
Is there enough available sunlight in all areas?
Requires a backup hot water source
Solar Cells (Photovoltaics)
How it works:Converts sunlight to electricity!Sunlight strikes semi-conductorElectrons are excited and move; creates
electricity.Energy can be stored in a chemical battery for
use when sunlight is absent.
Photovoltaics (Solar Cells)
Photovoltaic Solar Cells
ADVANTAGES
Free energy
Renewable
Clean
Safe
DISADVANTAGES
Expen$ive!
Need large surface area
Unattractive
Is there enough available sunlight in all areas?
Requires a backup electricity source
Solar-Thermal Systems
Used to generate High-temperature heat and electricity.Central receiver = Power Tower!
w/ heliostats
Solar thermal plant
Power Tower!
Aka
Central Receiver System
Solar thermal plant
Oil-filled pipes collect the sun’s heat energy
Wind Energy How it works:
Sunlight heats Earth’s surface
Warm air rises; cooler air replaces it (wind)
Wind (mechanical E) turns giant blades
Connected to a generator; creates electricity
Wind Energy
ADVANTAGES
Free energy
Renewable
Clean
Well developed technology
Electricity is cheaper per watt than coal produced.
DISADVANTAGES
Unattractive
Few regions with consistent winds
Noisy
Interfere with microwave communications
Harm birds & wildlife
Wind Energy
Wind energy
http://www.youtube.com/watch?v=fNudnI5tzf8
Hydroelectricity
How it works:Dam is constructed to make a reservoir
Need height change to create enough power of moving water
Flowing water through dam turns turbines, turns generator, makes electricity
Hoover Dam
Hydroelectricity
ADVANTAGES
Free energy
Renewable
Clean
Flood control
Reservoir for recreation & irrigation
DISADVANTAGES
Disrupts ecosystems & floods upstream land
Tremendous environmental damage during construction
Dam construction is extremely expensive
Limited to areas with rivers & streams
Geothermal Energy
How it works:Uses Earth’s heat to create steam to make
electricityHot Dry Rock Method
Pump cold water below ground Turns to steam Extract pressurized steam Turns turbine, turns generator, creates electricity
Geothermal Energy
Geothermal Energy – Heat pumps
Geothermal Heat Tubes
Geothermal Energy
ADVANTAGES
Free energy
Potentially Renewable***
No greenhouse gases
Minimal environmental damage during set-up
DISADVANTAGES
Limited availability on Earth.
Earth takes a long time to replace the heat.***
Biomass How it works:
Burn organic matter to produce heatExamples:
Wood (#1 in world usage) Municipal Waste (garbage) Sugar cane (Hawaii) Chicken droppings
Biofuels Gaseous liquid
Waste to Energy Plant
Biomass
ADVANTAGES
Reduces “wastes”
Renewable
Conserves fossil fuels
Sell extra electricity to public
DISADVANTAGES
CO2 emissions
Noxious gases released
Who wants to live near a plant that burns trash or chicken poop?
Tidal Energy
How it works:Offshore Turbines
Similar to underwater windmills
Tidal Barrage Similar to hydroelectric dams
Offshore Turbines
Tidal Barrage
Tidal Energy
ADVANTAGES
Free energy
Renewable
Clean (non-polluting)
DISADVANTAGES
Affects ecosystems
Unattractive
Expensive to build
Affects shipping
Hydrogen Fuel Cells
Fuel source
Decomposition of water
2H2O 2H2 + O2
Combustion2H2 + O2 2H2O
water
Days or weeks
Ele
ctric
ity,
heat
or
light
Sto
rag
e a
nd t
rans
por
t
Electricity!
Waste heat
The Hydrogen energy cycle.
http://www.pbs.org/wgbh/nova/tech/fuel-cells.html
Hydrogen Fuel cells cars
NissanNissan
HondaHonda
Fueling StationFueling Station
What’s Next? Choose. You Choose.