Large Scale Sources of Electrical Energy Lesson 4

Around 89% of all of the energy resources used in Canada are non-renewable. If focusing on electricity generation alone. 59 - 69% of electricity in Canada is from Hydroelectric, the rest is from the combustion of gases or nuclear power plants and only 1.3% is from renewable energies

Generators A generator is a machine that turns mechanical energy into electrical energy It needs energy to turn wire coils in the magnetic field of the permanent magnets.

Non-renewable Resources

Fossil Fuel generating stations Fossil fuel generating stations can use three main types of fuel; Oil, coal and natural gas. The gas is burned, and the chemical energy released is used to heat water and produce steam (1). The high pressure steam is then used to turn a set of fanlike wheels called turbines (2).

Fossil Fuel generating stations As the turbine wheels spin, they turn an electromagnetic generator (3) that finally produces electrical energy. This electrical energy is then converted in a transformer (4) to the correct voltage before it is sent to people’s homes.

the fuel is burned to boil water to make steam the steam makes a turbine spin the spinning turbine turns a generator which produces electricity the electricity goes to the transformers to produce the correct voltage

Of the total electricity generation in Canada, approximately 17% (107 million megawatt hours) can be attributed to the combustion of coal and oil. Steam electric plants (boilers), combustion turbines, and internal combustion engines currently provide a generating capacity of 36,300 megawatts. Coal-fired boilers account for 73% of this capacity. Natural gas uses the same technique but is much cleaner and produces 5% of Canada’s energy, but its supply is limited.

Environmental issues due to pollutants Coal and oil-fired facilities account for the majority of air emissions from the electric power sector. Emissions Environmental issues due to pollutants -Carbon dioxide -Toxic metals - Acid Rain -Sulphur dioxide -mercury - Smog -Particulate matter - Nitrous oxides - toxic substances -Climate change

Nuclear Generating Stations Of the total electricity generated in Canada, approximately 15% (72 million megawatt hours) is nuclear energy. Current nuclear generating capacity is about 10,301 megawatts. The process of nuclear generation is very similar to that of fossil fuels. The basic difference is that instead of chemical energy of fuel to heat water, the energy used is from nuclear reactions. Nuclear reactions occur when uranium atoms are split by bombarding the atoms with neutrons.

Nuclear Generating Stations The reaction is called nuclear fission and it creates enormous amounts of heat which is used to heat water that is converted into steam which powers turbines. The turbines then turn a generator which produces the electricity

Nuclear Generating Stations

Nuclear Generating Stations The use of nuclear power plants is controversial. Below is a list of pros and cons for the use of nuclear power. Pros Cons -Low amounts of CO2 production -Available to use now, it does not need to be developed -Large amounts of power from one plant -Radio active waste -Risk of accidents -Limited supply of uranium -takes 20 -30 years to build a plant -Heats up large amounts of water

Renewable Resources

Hydroelectric Power Of the total electricity generated in Canada, approximately 60% (350 terawatt hours) is from large-scale hydro power. Current hydro generating capacity is approximately 65,000 megawatts. A hydro electric power plant uses the energy of falling water to turn a turbine. The turbine is attached to a generator which sends the power generated to a transformer which converts the energy to a suitable voltage to be send on the power lines.

Hydroelectric Power

Hydroelectric Power Pros Cons -Renewable -Low emission - Destroys land animal habitat - Destroys fish habitat - Submerged vegetation emits greenhouse gas. - Mercury in rocks is released into the food chain by bacteria on the rotting vegetation.

Other Renewable Resources (Green Power) Sources of green power are wind, solar, tidal, geothermal, biogas-fuelled and biomass-fuelled power sources. These sources have little or no greenhouse gas emissions, and smog, acid-rain or toxic pollution are zero. While green power currently makes up only a small percentage of Canada's electricity, Canada's green power resource potential is enormous - perhaps sufficient to account for up to half our electricity needs, contributing to substantial reductions of greenhouse gas and other air pollutant emissions compared to conventional fossil-fuelled generation. Growth of the industry would also provide significant potential for innovation, job creation and regional diversification.

Wind Power Wind power is created by using windmills. The wind turns giant rotors that turn electromagnetic generators. These generators then send the power to transformers which then convert the voltage to a useable amount before it is sent into distribution. These can now be seen popping up all over Canada.

Wind Power Pros -No Pollution Cons Need wind Small amount of energy produced Needs lots of space Kill birds

Solar Power The sun is used to knock elections off atoms. The electrons flow then creates a current which must be converted into AC by an inverter.

Solar Power Pros Cons -No pollution -Reliable -Need a lot of light -Small amount of electricity -Expensive

Biomass Methane produced from rotting garbage and waste is burned. This is then used to heat water and use the steam to turn a turbine to create electricity.

Biomass Pros Cons -readily available -Simple -lots of energy lost -Pollution

Geothermal With Geothermal, water is pumped down into the earth where it is really hot. The water turns into steam which then rises to the surface and turns a turbine which turns a generator and creates electricity.

Pros No Fuel needed Sustainable Cons Expensive May cool down

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