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What is Renewable Energy?

Renewable energy is any sustainable energy source that comes from the natural environment. The most common forms of renewable energy are solar, wind, water or hydro, biomass and geothermal energy. Renewable energy sources are maintained or replaced by nature after use. Other energy resources, such as coal, oil and natural gas, cannot be replenished by nature as fast as they have been used; it took hundreds of millions of years to form fossil fuel deposits and they are in limited supply.

Sunlight, wind, water and biomass are the sources for most of Canada's renewable energy. Sunlight can be converted to electricity using photovoltaic (solar electric) panels. This electricity can be used to operate a multitude of electrical appliances. The sun's energy (light, heat, ultraviolet) can also be converted into heat using solar thermal (heating) panels. The heat can be used to heat water or air for residential, commercial and industrial use.

Wind and flowing water can be used to generate electricity.

Trees can provide wood for heating and materials for buildings, while grains, such as corn and wheat, can be fermented into ethanol and used as a fuel for automobiles.

Reasons for Renewables

Global environmental concerns, the depletion of the earth's finite resources and economic considerations are all incentives to interest consumers in renewables. Although renewables cannot yet replace all existing energy sources, they can supplement power generated by utilities and increase the diversity of our energy supply. Global climate change due to pollution and the effects of pollution on the environment have become major environmental issues since the Rio Summit in 1992.

As well, the two oil crises in the 1970s forced the industrialised world to examine carefully its resource use and reconsider its virtual dependence on a single fuel source. Intensive research has been undertaken in the developed world to find technology-driven clean energy substitutes for traditional fossil fuels.

The rapidly increasing industrialisation in developing countries puts a strain on already limited resources and adds to the continuing deterioration of the global environment. Finding alternative sources of energy is crucial.

Economically, the advances that have been made in renewable energy technologies in the last two decades, including higher efficiencies, improved quality and increased reliability, have made applications of renewable energy more attractive. On a small scale, renewable energy is not competitive when compared to bulk power generation, but it does have practical applications in innovative niche markets, such as consumer products, remote/off-grid and telecommunication applications. The cost of renewable energy technologies will drop once the benefits of renewable energy, including its sustainable nature and the minimal pollution it creates, are recognized by a larger percentage of the population.

Renewables are Not New

Renewable energy sources have been used for centuries. Until the mid-1800s, most of our energy came from two biomass sources, wood and peat. The location of many large plants and mills during the industrial era in Europe and North America was determined by the availability of fast flowing streams to generate power.

It wasn't until the latter stages of the Industrial Revolution, the mid-1850s, and following the widespread incorporation of the steam-engine into factories, that fossil fuel use, mainly coal and oil, became commonplace. By incorporating fossil fuels into the manufacturing process instead of using water, industrialists were not limited to locations by rivers or streams. Plants could be located closer to sources of raw materials, markets or major shipping ports.

Renewable Energy in Remote Areas

One of the greatest benefits of renewable energy is its potential to provide affordable and clean sources of electricity to remote populations in Canada and to developing countries. Although many people do not have an economical connection to an electrical grid, renewable energy technologies can capture natural sources of (electrical and heat) energy in non-conventional locations and in non-conventional ways. It has been estimated that up to three billion people do not have electricity and renewable energy can play a key role in the economic development and modernisation of areas where many of these people live.

Renewables and Global Warming

The earth's atmosphere acts like glass in a greenhouse: sunlight can pass through, but the resulting heat can not escape. Gases, such as carbon dioxide, are particularly effective at trapping heat. When burned, coal, oil and natural gas increase the amount of carbon dioxide in the atmosphere and the earth's average temperature is raised. Renewable energy initiatives will result in reduced demand for fossil-fuelled electricity generation, thereby reducing greenhouse gas emissions.

Renewing Sustainable Development

In 1987, a United Nations commission chaired by Gro Harlem Brundtland, the then Norwegian Prime Minister, was formed to determine how to reconcile economic development with environmental protection. The term 'sustainable development' was first used in the commissions' report, Our Common Future. The report recognized that renewable energy sources are essential for sustainable development because they provide us with constant sources of energy with fewer effect on the environment. It also identified that globally, there was the need for more efficient use of energy and that the industrialised world, especially, had to improve its conservation efforts to lessen the impact of economic development on the environment.

Renewable Energy Sources

The following terms are used to describe the various forms of renewable energy:

Active solar energy
The sun can be used directly to heat water for pools, homes and industry, to provide space heating and to generate electricity. The sun's energy can also be used to distill water and cook food.
Biomass energy
The sun's energy is stored in organic materials such as wood, grains and peat. Wood and peat are both burned to provide heat. Grains can be fermented into ethanol and used as a liquid fuel.
Geothermal energy
Heat from the earth's core can be used to generate electricity. It can also be used directly (with heat pumps) to heat and cool buildings.
Passive solar energy
Passive solar energy is incorporated into energy efficient building and landscape design, e.g. window placement to heat retaining walls and floors.
Small hydro
Small hydro projects will generate power by using falling water at an average capacity of 20 megawatts or less. A 'run-of-the-river' project also uses falling water by directing water to the turbine using pipes, rather than dams.
Wave or tidal energy
The movement of waves and tides, particularly in shallow water, can be harnessed and converted to electricity.
Wind Energy
The energy from the wind can be harnessed by wind turbines and windmills to generate electricity and also to pump water.

References

World Commission on Environment and Development,
Our Common Future, (Oxford: Oxford University Press, 1987).
Davidson, Alex, and Michael Dence,
The Brundtland Challenge and the Cost of Inaction, (Halifax: The Royal Society of Canada and The Institute for Research on Public Policy, 1988).
Noble, Duncan and Robert K. Swartman,
The Canadian Renewable Energy Guide, (Burnstown: General Store Publishing House, 1995).
Woods, Elizabeth,
If Only Things Were Different: A Model for a Sustainable Society, (Victoria: Woods Works, 1992).

Information

For more information on renewable energy sources, active solar energy, passive solar energy, and photovoltaic solar energy, please contact:

Solar Energy Society of Canada Inc.
Tel: (613) 234-4151
Email: sesci@sympatico.ca

Canadian Solar Industries Association
Tel: (613) 736-9077 
Email: cansia@magmacom.com

Canadian Wind Energy Association
Tel: 1 (800) 922-6932 
Email: canwea@cadvision.com

Kortright Centre for Conservation 
Energy Theme Co-ordinator 
Tel: (905) 832-2289  
Email: kcc@interlog.com

Natural Resources Canada
Tel: (613) 996-6220
Email: rudy.lubin@nrcan.gc.ca

Ontario Hydro, Environment and Sustainable Development Division
Jackie Hennessy
Tel: (416) 592-8487
Email: jackie.hennessy@hydro.on.ca

Ontario Ministry of Environment and Energy
Tel: (416) 325-4000

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E-mail: sesci@sympatico.ca
29 November 1997 URL: http://www.newenergy.org/newenergy/sesci/publications/pamphlets/renewable.html