Renewable Energy

Solar Solar energy is harnessing energy from the sun’s rays – Passive Solar – Placing buildings strategically to take advantage of the sun’s heat Example: Log Homes – Active Solar – uses solar panels to convert energy into a usable form such as electricity

Benefits of Solar: – Readily available – Renewable – Fairly simple system – Pollution free energy source – Can sell back extra energy to the power company Drawbacks of Solar: High start up cost for active solar energy system Location dependent (Seattle would not be a good city for solar energy)

Wind Wind energy is converted into a usable energy form by using wind turbines

Benefits of Wind Power: – Readily available – Can sell back extra power – Pollution free energy source Drawbacks of Wind Power: – Disrupts migration patterns – Turbine farms are not aesthetically pleasing – Turbines are expensive – Good for specific locations only

Hydro Hydro power is mechanical energy derived from water Most hydropower is generated by damming rivers Using waves or ocean currents is being researched as a source of hydropower

Three Gorges Dam in China

Three Gorges Dam 1.5 miles long 574 feet deep $23 billion 13 cities and 1,300 villages were flooded

Benefits of Hydropower – Readily available – No pollution produced – Constant source of power Drawbacks of Hydropower – Damming rivers disrupts ecosystems, causes sediment to build up and disruptst he natural flow of a river

Geothermal Geothermal energy uses natural underground heat sources When heat escapes the earth in the form of steam, the steam is used to turn a steam turbine which converts the heat energy into electrical energy

Benefits of Geothermal: – When drilled correctly, little pollution is produced – Takes up a relatively small area, does not disrupt the landscape Drawbacks of Geothermal: – Can only be used in a limited capacity – Very location specific – May run out of steam – May release hazardous gasses or minerals if drilled improperly

Biomass Biomass is burning biomass fuel in a specialized burner. Steam generated turns a steam turbine which turns mechanical energy into electrical energy

Biomass at the Denver Zoo! Trash and animal waste is converted into pellets The pellets are put into a gassifier and heated to 400 degrees! When hot enough, a gas is emitted that is converted by micro gas turbines into electrical energy Denver Zoo

Benefits of Biomass – Less waste in landfills Readily available Drawbacks of Geothermal – Not currently available on a large scale basis