renewable energy sources

Types Drawbacks

Wind Power Windmills have

been used for thousands of years

to mill grain, power sawmills and pump water.

Picture is of a Dutch windmill in Amsterdam built in 1757.

Wind PowerBenefits:

“Free” and clean. No digging to get it. Could produce

20%of our energy needs.

Drawbacks: Takes up space. Wind farms stand

idle 65-80% of time due to lack of wind.

No good way to store energy.

Blades can kill birds and bats.

Wind PowerThese things are huge!! Each blade of a standard commercial windmill is 100 ft. long. Some people complain that they block the scenery or view.

Wind farms have been proposed in Lake Erie and in New York state along the lake shore.

Water PowerWaterwheels have been used for thousands of years to mill grain and power machines.

Picture is of a waterwheel grist mill in Old Sturbridge Village

Water Power (Hydroelectric)Flowing water turns the wheels of a turbine which turns the shaft of a generator which generates the electricity.

Water Power (Hydroelectric)Picture of Hoover Dam in Nevada.

Water Power (Hydroelectric)The water from the Niagara River above the Falls was used to power the first hydroelectric power plant in the world. It was built in 1922.

Water Power Benefits:

“Free” limited, but reusable.

No digging to get it. Clean source of energy.

Drawbacks: Need to have a water

flow so it can only be used in certain areas.

Would provide small amount of our energy needs.

Solar PowerScientists say that Solar is the only renewable source capable of producing all our energy needs. The total power of the sunlight reaching the earth is 101,000 terawatts. Our current energy needs are 15 terawatts.

The picture is a solar farm in Sahara Desert.

Solar Power•Benefits:

• “Free”, clean and unlimited.

• No digging to get it.• Capable of producing all

our electrical needs.•Drawbacks:

• Works best in sunny areas, but can work in Erie, PA. (Home at right is in Erie)

• Takes up space.• Expensive and no way to

store energy for long periods of time

Collegiate Academy Solar Panels were installed in October 2009.

Below the surface of the earth the ground temperatures range from 45°F (7°C) to 75°F (21°C). Like a cave, this ground temperature is warmer than the air above it during the winter and cooler than the air in the summer.

The picture to the right is the geothermal field at Asbury Woods Nature Center. It is all underground so you can’t tell it is there.

A series of wells are dug for the pipes that carry a water/alcohol mix so it can reach a constant temperature.

Asbury Woods Nature Center has 16 wells at 300 ft. deep. At that depth, the ground temperature is 50°F. When the liquid gets to that depth it also becomes 50°F.

Electric pumps constantly bring the 50°F liquid into a heat transfer pump in the basement. The stored heat is used to heat the building during the winter. The opposite happens in the summer so you have instant air conditioning. There is a cost for the electric pumps and blowers, but, no more gas heating bills, or air conditioning bills.

Benefits: Can be used for homes and commercial buildings. Have lower operating costs than conventional heating and

cooling systems. The systems use 25% to 50% less electricity than

conventional electric heating or cooling systems. They are easier to maintain than conventional systems They are also quieter than air conditioners No more gas bill.

Drawbacks: Use of geothermal systems depends on the climate, soil

conditions, available land, and local installation costs. The primary argument against geothermal systems is their

cost.

Biofuels use plant materials to produce fuel. Corn, soybeans and even used cooking oil are used to produce biodiesel fuels.

Soybean field at right is on Sterrettania Rd. in Fairview, PA.

Biodiesel Plant in Erie, PA. Millcreek Township

School District Buses use 25,000 gallons of Biodiesel per year from the HERO Plant in Erie.

Benefits Renewable Corn and Soybeans are already produced in the United States Release less soot and other particulate matter into the

atmosphere than petroleum based gasoline and diesel fuels. Emit only the CO2 into the air that the plants have just taken in

for growth, so you are not putting extra CO2 into the air that happens when you burn petroleum based fuels.

It is easier to covert businesses, homes and vehicles to biofuels rather than wind or solar

Drawbacks There aren’t many gas stations that are set up to offer biofuels. The crops and land needed to raise biofuels will require more

forested land to be converted to farmland. Studies show that the energy needed to grow crops and then

convert them into biofuels will be more than what is produced.

Sahara Desert Solar Farm photo used with permission of the Rochester Public Utilities.

Worker inside the windmill photo used with permission of the NW Public Utility Service, Sumner, WA

Other photos are free downloads from Dreamstime.com, or taken by author.

Solar home in Erie taken with permission of Dave Skellie.