The ocean is a vast source of energy that can be harnessed to produce different forms of usable energy. For instance, technologies have been developed to convert the energy of ocean waves and tides into electricity or other useful forms of power. However, a number of technical, economic and environmental barriers remain and, as a result, ocean energy is currently not a widely exploited energy source.

Source: Natural Resources Canada

The kinetic energy in wind can be converted into useful forms of energy such as mechanical energy or electricity. Wind energy has been harnessed for centuries to propel sailing vessels and turn grist mills and water pumps. Today, wind is used increasingly to generate electricity. Turbines with large propellers are erected on ‘wind farms’ located in strategic areas that have good wind regimes and that are in proximity to existing electrical grids. Wind energy is captured only when the wind speed is sufficient to move the turbine blades, but not in high winds when the turbine might be damaged if operated.

Source: Natural Resources Canada

Geothermal energy can be captured from the heat stored beneath the earth’s surface or from the absorbed heat in the atmosphere and oceans. In the first instance, geothermal energy can be captured from naturally occurring underground steam and be used to produce electricity. In the second instance, heating and cooling can be achieved by taking advantage of the temperature differential between outside air and the ground or groundwater.

Source: Natural Resources Canada

To learn more on the installation and maintenance of a geothermal system, download Residential Earth Energy Systems: A Buyer's Guide, published by Natural Resources Canada.

Bioenergy comprises different forms of usable energy obtained from materials referred to as biomass. A biomass is a biological material in solid, liquid or gaseous form that has stored sunlight in the form of chemical energy. Excluded from this definition is organic material that has been transformed over long periods of time by geological processes into substances such as coal or petroleum.

Several types of biomass can be used, with the proper technology and equipment, to produce energy. The most commonly used type of biomass is wood, either round wood or wood waste from industrial activities. Wood and wood waste can be combusted to produce heat used for industrial purposes, for space and water heating, or to produce steam for electricity generation. Through anaerobic digestion, methane can be produced from solid landfill waste or other biomass materials such as sewage, manure and agricultural waste. Sugars can be extracted from agricultural crops and, through distillation, alcohols can be produced for use as transportation fuels. As well, numerous other technologies exist or are being developed to take advantage of other biomass feedstock.

Source: Natural Resources Canada

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.

Source: Natural Resources Canada

To learn more about hydroelectricity, visit Hydro-Québec's website.