What is Green Power?
According to a Pembina Institute report, the two primary characteristics of green power are: Electricity is generated from renewable resources and does not compromise the ability of future generations to access reliable, efficient and affordable energy supplies.
Electricity is generated as to ensure health and environmental quality. According to BC Hydro, power projects qualify as "green" under the following criteria:
- Renewable: The energy source must be replenishable by natural processes within a reasonable length of time - at the longest, within about one average human life span. For example, hydroelectric generation relies on water, which is a renewable resource. Natural gas electrical generation relies on a fossil fuel, a resource that does not meet this renewable criterion.
- Licensable: The project must meet all relevant regulations an standards.
- Socially responsible: The project must be developed in a socially responsible manner. This criterion must be judged on a site-specific basis. Every project within BC Hydro's green acquisition process is reviewed according to specific social responsibility criteria.
- Low environmental impact: The project must avoid unacceptably high environmental impacts such as damage to fish populations, endangered species, or air quality. This criterion is evaluated on a site and technology-specific basis. Every green project within BC Hydro's acquisition process is reviewed according to the criteria that correspond to the project's technology.
Emission offsets are the avoided environmental costs of producing electricity from renewable energy sources rather than from thermal (fossil fuel or non-renewable) sources. Most of British Columbia's power is derived from large hydroelectric facilities, however some energy is imported from the United States and Alberta. Imported electricity was used to cover approximately 15% of BC demand in 2006 and this number is expected to increase. Most electricity generated in Alberta is from coal and natural gas, while a large portion of electricity produced in Washington State is generated from natural gas and nuclear. Therefore, by developing green power projects within the province, British Columbia reduces its reliance on imported electricity generated from "brown" or non-renewable sources, thus offsetting the greenhouse gases emitted from these facilities.
There are a number of methods whereby the potential emission offsets are calculated. One method is that for every mega-watt-hour of green power produced, 0.36 tonnes of CO2 is displaced from thermal power plants. In other words, a power plant that produces 50 GWh/yr (50,000 MWh) of energy has the potential to displace nearly 26,000 tonnes of CO2 annually. This is equivalent to the amount of carbon dioxide emitted by approximately 5200 cars per year. It is also approximately equivalent to the amount of CO2 absorbed by over 4000 hectares (or, approximately 9900 acres) of trees.