[This print version is largely duplicated in our interactive Power Generation Map.]
From the late 1800s, when the first hydropower turbines were installed on Northwest streams, into the 1960s, water power supplemented by small steam plants fueled by coal, oil, and wood, provided most of the electricity in the Pacific Northwest. Then, as population increased and the regional economy grew, demand for electricity surpassed the output of the dams. Other types of power plants were built, steadily adding to the region’s electricity supply. Primarily, these were baseload coal and nuclear steam-electric plants and small peaking combustion turbines fueled by natural gas. Later, the system was further expanded by the addition of highly efficient natural gas combined-cycle plants. Recently, large numbers of wind turbine generators have been added to the system.
Electricity in the Northwest is still dominated by hydropower, which accounts for about 58 percent of the installed capacity. The amount of hydropower varies with water conditions. Most of the region’s hydropower is generated on the Columbia River and its tributaries, but there are also dams on other rivers, particularly those that empty into Puget Sound. In years when precipitation and runoff are normal, the region’s hydroelectric system can provide about 16,000 average megawatts of electricity (an average megawatt is one million watts supplied continuously for a period of one year). In approximate number, the amount can be as much as 20,000 in a wet year or as little as 12,000 in a dry year. About 12 percent of the region’s electricity capacity is at plants that burn coal, with plants that burn natural gas providing 16 percent. The region’s single operating nuclear plant, located in eastern Washington, accounts for about 2 percent of the region’s capacity. In all, the region’s power supply capacity totals about 59,000 megawatts.
The map in this brochure shows the diversity of the modern power supply in the Northwest, but not all of the power plants. The smallest plants are not shown because there are so many. The map also doesn’t depict the most important resource to the Power and Conservation Council — energy efficiency. Consistent with the Northwest Power Act of 1980, the federal law that authorized the four Northwest states to create the Council, energy efficiency gets planning preference over all other sources of electricity to meet future demand for power. At a cost that is less than the cost of building new generating plants, measures can be implemented to improve energy efficiency — insulation, double-paned windows, compact fluorescent light bulbs, low-wattage traffic lights, and energy-efficient industrial motors, for example. Between 1983 (when the Council completed its first Northwest Power Plan) and 2008 more than 3,700 average megawatts of energy efficiency have been achieved in the Northwest. Expressed as energy generation, that is more than enough power for three cities the size of Seattle.
