Gov. Jay Inslee wants to take that down to zero over time.
To wean the state off coal-generated power, the Democratic governor will have to persuade the state's three private electric utilities - Puget Sound Energy, Pacific Power and Avista Corp. - to reduce or eliminate electricity they get from plants in Montana and Wyoming.
The utilities say coal-fired electricity is reliable and cost-effective and only part of a diverse portfolio that includes hydropower, natural gas and wind, and for now coal appears to be a part of their long-term energy plans.
Saying the state has a moral responsibility to act on climate change, Inslee signed an executive order last month directing state agencies to negotiate with utilities to phase out electricity produced from coal.
"It's not a trivial activity by any means, but I think it can be done," said Tony Usibelli, director of Washington's energy office, on eliminating coal-fired electricity from the state's fuel mix.
The state's only coal-fired power plant, the TransAlta facility in Centralia, is slated to shut down by 2025. Most of the state's coal-fired electricity, or coal by wire, is imported from the Colstrip power plant in eastern Montana and the Jim Bridger plant in Wyoming.
One elected official in Montana recently criticized Inslee's proposal as job-killing, while environmentalists cheered it as a big step toward making Washington coal-free.
"We have an unparalleled opportunity to be carbon free," said Doug Howell with the Sierra Club, which has targeted Colstrip and other coal-fired power plants over environmental and public health concerns from burning coal.
But Colstrip has its supporters. The mayor of the city of Colstrip, Rose Hanser, said Inslee's push would have serious consequences for jobs and people in her region.
"How are you going to provide this kind of energy at this dollar amount, and where are you going to replace these family wage jobs?" said Hanser.
Puget Sound Energy is the largest owner of the four-unit Colstrip plant, which can produce enough electricity to power about 1.75 million homes. PPL Montana operates the facility on behalf of six utilities, including Avista and PacifiCorp.
"Today, Colstrip is providing very cost-effective environmentally compliant electricity," said Grant Ringel, a PSE spokesman. He said regulations, the costs of coal or maintenance, or other factors "will drive whether or not it will make sense in the future."
PSE is a leading provider of wind energy, but coal made up about 30 percent of its fuel mix in 2012, according to the state's fuel mix disclosure report. In February, state utilities regulators asked the company for more information to determine whether it makes sense for the utility to continue to rely on the older coal-fired power plants in Colstrip.
Jessie Wuerst, a spokeswoman for Spokane-based Avista, said Colstrip "is a part of our long-term planning and remains in our long-term planning."
"It remains very reliable and inexpensive," she added.
Wuerst said that it would cost ratepayers about $50 million a year or more if the utility replaces electricity it gets from Colstrip.
Scott Bolton, vice president of community and government relations with Pacific Power, a subsidiary of PacifiCorp, said the utility has a diverse portfolio including hydroelectric, natural gas and wind power.
Coal-fired generation makes up the majority of Washington's electricity-related carbon pollution, and about 16 percent of the state's total greenhouse gas emissions.
With a host of potential new federal regulations on the horizon, coal-fired plants will have to make decisions in the future about whether to spend millions of dollars to upgrade their facilities to new standards, or close them, Sierra Club's Howell and others said.
"Coal is a very dirty resource," said Dave Danner, chairman of the Washington Utilities and Transportation Commission, which regulates the utilities.
The utilities submit plans every two years that look out over the next 20 years on what resources they need to provide service at the lowest cost, he said. All three will be submitting plans that make assessments about whether coal will be most cost effective resource, he added.
"We're going to look at the data, look at the information, look at modeling," Danner said. "But utilities themselves are aware of what their customers want. The people in Washington want to be coal-free."