Renewable energy resources and the environment

Introduction

Renewable energy sources produce electricity or thermal energy (steam or heat) without depleting resources. They include water, wind, solar, geothermal and biomass power, and energy from biomass waste. Renewable energy is replenished through natural processes or through sustainable management practices.

Renewable resources have long been an important source of energy. Wood has been used for centuries for space heating and cooking, and water and wind have been harnessed to generate mechanical power. Our ancient ancestors used geothermal heating and cooling when they lived in caves, and later when they used root cellars to prevent vegetables from freezing or spoiling.

In recent years, interest in these sources has grown as environmental awareness increases in our society and as governments and industry look for environmentally attractive alternatives to the use of fossil fuels.

Currently, hydroelectricity accounts for about 17 per cent of Canada’s primary energy supply. Canada has abundant water resources that provide a source of low-cost electricity. Thanks to a number of large hydro projects developed by electricity utilities over the past few decades, Canada obtains about 60 per cent of its electricity from hydro power.

Most of our country’s remaining renewable energy supply comes from biomass, which is produced by burning wood or plant materials and wastes, or converting these to gas or liquid fuels.

Other emerging forms of renewable energy in Canada include:

• wind for electricity generation and mechanical power
• geothermal for water heating, space heating and cooling, and electricity generation
• solar for thermal energy and electricity generation

Biomass and other emerging forms of renewable generation capacity contribute about three per cent of Canada’s electricity supply.

In many cases, the use of renewable energy can provide important environmental benefits, such as reduced impacts to air, land and water. It is also the driver behind a small but growing industry. In 1998, the renewable energy industry (excluding large hydro) employed nearly 5,000 Canadians and contributed about $1.1 billion to the economy.

But like other energy options, each renewable energy source has environmental impacts that must be considered, as part of energy planning and use.