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.