Other electricity generation sources

Biomass

Biomass energy is derived from many different types of recently living organic matter (feedstock). However, in the context of producing large-scale energy, it is likely that the focus would be on harvesting forestry products as fuel for the biomass generator. Biomass works similar to many other thermally-based generators in that wood or other biomass products are harvested, treated and then transported to the generation plant to be used in place of other solid fuels such as coal to generate heat. The heat is then used to produce steam. The steam is in turn fed into a turbine that turns a generator to produce electricity.

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Coal

Coal has a long history as a fuel source in North America. It has been used to heat homes, power machinery and transportation, and power electric generators. While most of coal's uses have been phased out, coal remains a significant fuel-1 source for electrical generation. According to the federal government there are 51 coal burning units in Canada, which account for approximately 19 percent of the electric generating capacity in the country.

Coal-fired generating capacity produces 13 percent of Canada's total greenhouse gas (GHG) emissions. Of the 51 coal fired generating units, 33 are expected to come to the end of their economic lives by 2025.

Coal-fired electric generation draws its fuel from vast reserves of non-renewable, naturally occurring deposits of coal. Coal reserves are mined, processed and transported to the generation site where they are pulverised and fed into a boiler to generate heat energy. The heat energy is used to produce steam. The steam is used to power a turbine which turns an electric generator.

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Combined Cycle Combustion Turbine

A combined‐cycle combustion turbine (CCCT) consists of a simple cycle combustion turbine, a heat recovery steam generator (HRSG), and a steam turbine generator. CCCT technology is widely used in North America as a flexible and efficient generating alternative.

The exhaust of the CT is passed through a HRSG to produce steam. Steam from the HRSG powers the steam turbine generator. The condensed steam is then recycled back into the HRSG. The CT provides about two-thirds of the generated power and the steam turbine about one-third. The heat recovery from the CT provides a large efficiency improvement over a stand-alone CT.

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Geothermal Energy

Geothermal energy is heat energy that is contained within the earth. The temperature of the earth increases with depth and results in hot water zones deep in the earth's crust. By drilling deep wells into the earth's crust the hot water can be intersected and brought to surface and used to power generators to make electricity. The hot water can also be used to directly to heat buildings, pools, etc.

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Natural Gas

Natural gas is used as a fuel source for combustion turbines and combined cycle combustion Turbines.

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Nuclear

A nuclear reactor uses controlled nuclear reactions to produce heat energy. The heat energy is then used to produce steam. The steam is used to turn a steam turbine, which turns an electric generator to produce electricity.

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Simple Cycle Combustion Turbines

A simple cycle combustion turbine power plant (CT) consists of an air compressor, combustion chamber, turbine and generator. CTs can be operated using either natural gas or light fuel oil (LFO). CT operation begins with air being drawn into the front of the unit, compressed in a compressor, and mixed with natural gas or LFO in the combustion chamber. Next the mixture of compressed air and natural gas or LFO is ignited producing hot gases that rapidly expand. The expanding hot gas is passed through a turbine which turns an electric generator to produce electricity.

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Solar

Solar power is the conversion of sunlight into electricity. This is carried out by two main methods:

  1. Using sunlight indirectly, Concentrating Solar Power systems use lenses or mirrors and tracking systems to focus a large area of sunlight into a small beam to boil water which is then used to provide power.
  2. Using sunlight directly, a solar cell, or photovoltaic cell, is a device that converts light into electric current using the photoelectric effect. Currently in Canada, solar power is focused primarily on photovoltaics.

Photovoltaic (PV) literally means "light" and "electric." Photovoltaic technologies are used to generate solar electricity by using solar cells packaged in photovoltaic modules. The most important components of a PV cell are the two layers of semiconductor material. When sunlight strikes the PV cell, the solar energy excites electrons that generate an electric voltage and current. Extremely thin wires running along the top layer of the PV cell carry these electrons to an electrical circuit. A photovoltaic module is made of an assembly of photovoltaic cells wired in series to produce a desired voltage and current. The PV Cells are encapsulated within glass and/or plastic to provide protection from the weather. Photovoltaic modules are connected together to form an array. The array is connected to an inverter which converts the direct current (dc) of the PV modules to alternating current (ac).

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Wave and Tidal

Harnessing energy from the natural motion of the ocean currents and waves has long been considered and studied as a viable option for renewable energy production. Many different technologies have been proposed to approach the problem of extracting the wave and tidal energy to produce electricity.

Wave energy technologies work by using the movement of ocean surface waves to generate electricity. Kinetic energy exists in the moving waves of the ocean. That energy can be used to power a turbine. One type of wave generator uses the up and down motion of the wave to power a piston, which moves up and down inside a cylinder. The movement of the piston is used to turn an electrical generator.

Tidal power is based on extracting energy from tidal movements and the water currents that accompany the rise and fall of the tide. When the tide rises, the water can be trapped in a reservoir behind a dam. Then when the tide falls, the water behind the dam can be released through a turbine similar to a regular hydroelectric power plant.

The system uses sluice gates and a barrage to trap the ocean water when it reaches its high tide level. The water is released when the tide falls, and the movement of the water is used to turn a turbine and generator to produce electricity.

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