Courtesy: www.nrcan.gc.ca
What is Renewable Energy?
Renewable energy is energy derived from natural processes that are replenished at a rate that is equal to or faster than the rate at which they are consumed. There are various forms of renewable energy, deriving directly or indirectly from the sun, or from heat generated deep within the earth. They include energy generated from solar, wind, geothermal, hydropower and ocean resources, solid biomass, biogas and liquid biofuels. Biomass, however, is a renewable resource only if its rate of consumption does not exceed its rate of regeneration.
A wide range of energy-producing technologies and equipment have been developed over time to take advantage of these natural resources. As a result, usable energy can be produced in the form of electricity, industrial heat, thermal energy for space and water conditioning, and transportation fuels.
With its large landmass and diversified geography, Canada has an abundance of renewable resources that can be used to produce energy. Canada is a world leader in the production and use of energy from renewable resources. Renewable energy resources currently provide 18.9 per cent of Canada’s total primary energy supply.
Hydroelectricity is by far the most important form of renewable energy produced in Canada. Wind and bioenergy also make an important contribution to Canada’s energy mix. Wind and solar photovoltaic power are experiencing the highest growth rates.
Hydroelectricity
The natural flow of water in rivers offers kinetic power that can be transformed into usable energy. Early usages included mechanical power for transformation activities, such as milling and sawing, and for irrigation. As well, rivers have been used for transportation purposes, such as moving logs from forests to industrial centers.
Currently, hydroelectricity is the major form of usable energy produced from flowing water. To produce hydroelectricity, the water flow is directed at the blades of a turbine, making it spin, which causes an electrical generator connected to the turbine to spin as well and thus generate electricity.
The amount of energy extracted from flowing water depends on the volume of water and its speed. Usually, a hydroelectric station is built at a sharp incline or waterfall to take advantage of the speed gained by the water as a result of gravity. Dams are built at some locations to help regulate the flow of water and, therefore, the electricity generation.
Canada has many rivers flowing from mountainous areas toward its three bordering oceans. In 2014, Canada had 542 hydroelectric stations with 78,359 megawatts of installed capacity. These stations include 379 small hydroelectric facilities, that is, facilities with a nameplate capacity of 50 megawatts or less, and they together represent 3.6 gigawatts, which is about 4.6 per cent of Canada’s installed capacity.