Wind Energy

• Wind energy is harnessed by wind turbines, wind mills and wind pumps

• Used to create electrical power• Produces no greenhouse gas emissions

Advantages of using Wind Energy• Wind is created by air pressures, wave currents and

temperatures over bodies of water.– Thus wind energy is renewable as long as there is water on the planet.

• Produces no greenhouse gas emissions, as wind turbines use wind as a source of energy

• No fuel costs for wind sites, as wind is the ‘fuel’ for the equipment

• Only costs are cost of equipment and construction, land acquisitions and minimal maintenance costs

• Companies in the sector pass on benefits to communities by lowering electricity costs.

Disadvantages of using Wind Energy

• Approximately 6, 400 bird fatalities in U.S.A. each year caused by wind mills.

• Some communities around wind energy sites in countries believe windmills are an aesthetic disadvantage

• Noise factor limits the building of wind power sites in close proximity to each other as well as residential communities

• Varying strengths of winds year round mean there is no constant amount of wind available to generate electricity

Wind Energy – Disadvantages continued

• Not all regions worldwide can be used for generating wind energy– Sun unevenly heats the earth, with less heat & pressure near poles– Wind energy sites must be located in areas such as Europe, the

Atlantic Ocean, and the Northern Pacific Ocean

• Wind turbines are only effective if they are in a zone of a calculated Wind Power Density of 3(300–400 W/m2 at 50 m altitude) to 7 (800–2000 W/m2 at 50 m altitude)– These type of conditions are not ample when compared to the total

area of the earth– The United States only has 625,000 km2 with a classification of 3 or

higher.

Wind Energy in the World

• 2008: 121.2 gigawatts of world electricity was created using wind– approximately 1.5% of the worldwide consumption of electricity

• Countries utilizing wind power to generate significant amounts of electricity include: – Denmark: 19% of its electricity generated by wind– Spain and Portugal: 11%– Germany and Spain: 7%

• 81% of the worlds wind power installations are in Europe and the United States.

Wind Energy in the World continued• Wind energy industry beginning to play a major roll in the

economic energy marketplace – generating equipment and maintenance costUS$36 billion,– lowest maintenance costs - rivals hydroelectric power

• World Wind Energy Association predicts 160 MW generation of electricity by 2010, and a 21% increase in production per year

• Global Wind Energy Council predicts 15.7% increase in production by 2013

• End of 2008: maximum amount of power that can be economically extracted from wind is approximately 72 terawatts– 4.8 times the global electricity consumption of 15 terawatts in 2005.

Wind Energy Statistics

• Average 1 MW wind mill can generate approximately 3,066 MW·h– If total area that can be used for wind energy consumption in the

United States is utilized with these mills, approximately 734 gigawatts of electricity can be generated

– Excedes 474 GW of energy consumed in the U.S.A. in 2007.

• Cost per unit of energy produced was estimated in 2006 to be comparable to the cost of new generating capacity in the US for coal and natural gas:– wind cost was estimated at $55.80 per MW·h, – coal at $53.10/MW·h – natural gas at $52.50.

Hydro Energy

• Hydropower: power from force of moving water• Hydroelectric power generated by force of falling water• One of the cleanest sources of energy, and also the

most reliable and costs the least• Hydroelectric power plant converts water pressure into

electricity• Renewable source• Hydropower originally used for irrigation, and operation

of machines such as watermills, textile machines, and sawmills

How it Works• Water held behind a dam, forming an artificial lake, or reservoir• Force of the water being released from the reservoir through the dam spins

blades of a giant turbine• Turns potential energy of water gathered in dam reservoirs in high places,

into moving kinetic energy that rotates the turbines.• Turbines generate electricity by turning magnets around stationary metal

coils, until changes in the magnet’s polarity produces Alternating Currents; ie. AC.

• Turbine connected to generator that makes electricity as it spins • After passing through turbine, water flows back into the river on the other

side of the dam• Power generated passes through transformers to increase voltage and send

them to distribution facilities, in-charge of sending and regulating electricity through power lines

How it Works continued

• Second method: – Uses rise and fall of tides and the strong currents– Uses turbines that come in the form of rolling logs with horizontally

placed axes exposed to sea– As tide rises and falls, horizontal protrusions will spin like a log to

generate electricity– Similar to dam: sends the raw power to transformers and distribution

facilities for regulation

Advantages of using Hydro Power

• Once a dam is constructed, electricity can be produced at a constant rate.

• Low operation and maintenance costs.• If electricity is not needed, sluice gates can be shut,

stopping electricity generation.– Water can be saved for use another time when electricity demand is

high

• Dams are designed to last many decades– Can contribute to generation of electricity for many years

• Lake can be used for water sports and leisure activities– Large dams often become tourist attractions

Advantages continued

• Lake's water can be used for irrigation purposes.• Build up of water in the lake allows energy to be stored

until needed• Electricity produced by does not create green house

gases.– No pollution to atmosphere.

• Renewable form of energy; does not rely upon finite resources like natural gas or coal

• electricity costs lower and more stable because hydro power does not depend upon the price of uranium, oil, or other types of fuel

Disadvantages of using Hydro Power

• Dams: expensive to build and must be built to high standard– Must operate for many decades to become profitable

• Natural environment destroyed due to flooding• People living in villages and towns in the valley to be

flooded must move out– Farms and businesses lost– In some countries, people are forcibly removed

• Building of large dams cause serious geological damage– Ex. building of the Hoover Dam in the US triggered earthquakes and

depressed the earth’s surface

Hydro Energy in Ontario• Ontario Power Generation supplies about 85% of all

electricity consumed in Ontario• OPG working to develop resources in a safe and

environmentally responsible manner. Their projects include:– The Niagara Tunnel, when complete, will supply enough water to

OPG's Sir Adam Beck Generating Complex to power 160,000 homes annually.

– The 12.5 megawatt Lac Seul Generating Station recently completed.• Station built adjacent to existing facility: Ear Falls Generating Station.• New station captures water spilled past the existing station to maximize

use of available water resources at the site

Hydro Energy in Ontario continued

– OPG redeveloping three generating stations located on Upper Mattagami River and one on Montreal River• When completed, capacity of new generating stations will be 35

megawatts - 45% increase from the existing stations.

– OPG recently released the Notice of Commencement for the Little Jackfish project in Northwestern Ontario• Will generate up to 100 megawatts of new power

– Lower Mattagami project: currently in early planning stages• Project would add 450 megawatts of hydroelectric capacity to

Ontario’s electricity system