Updated May 8: This post was updated to reflect the governor signing the bill into law.

Dive Brief:

• Gov. Jay Inslee, D, on Tuesday signed Washington state’s 100% clean energy bill, making it the fourth state in the country to commit to such a goal.

• Senate Bill 5116 passed the House 56-42 without bipartisan support in April, and will require the state to power 100% of its electricity from carbon-free resources by 2045. The legislation phases out coal entirely by 2025 and requires all electricity sales to be carbon-neutral by 2030.

• Inslee released a clean energy legislative package in December, which included five policy goals to reduce the state's carbon emissions, including the 2045 and 2025 goals in the bill.

Dive Insight:

Washington is committing to 100% clean energy at a time when it is 75% of the way there. The majority of the state's energy portfolio — 67.68% — comes from hydropower, while coal and natural gas make up about 24%.

The bill passed along party lines, despite favorable conditions intended to spur Republican support.

“What we did hear a lot on the floor debate around the bills was just continued concerns around cost and reliability,” Lauren McCloy, senior policy energy advisor for Washington Governor Jay Inslee said during a telepresser before the bill’s signing.

Although provisions were added to quell utility concerns, it "simply wasn't enough to get us over the line to get us a bipartisan vote,” she added.

The state has a governor who has pushed hard on climate change for the majority of his career. Inslee in March announced that he would be running on the Democratic ticket for president in the 2020 election, and has made climate change a central component to his campaign.

Although the state already runs the majority of its power on renewable resources, it is not taking nuclear or other non-renewable, carbon-free resources off the table, consistent with Inslee's rhetoric on how to best propel the clean energy transition forward.

"I think that we have to be open to all low-carbon, zero-carbon potential sources given the urgency of this effort," he told reporters after an American Council on Renewable Energy event. He said development should focus on making nuclear energy cost-competitive and building better waste disposal systems or eliminating waste altogether.

The state has one operating nuclear plant that makes up a little over 4% of its generation mix. All its coal is imported from Montana and Wyoming, which powers its only coal plant, a 1,340 MW facility in Centralia, Washington.

While support for carbon-free generation is strong in the state, efforts to clean up existing carbon sources have failed — during the midterm elections, voters struck down a ballot initiative for a third time that would have added a carbon emissions fee.

Inslee noted that "90% of the [expected] carbon emissions reduction took place from the investment side not the pricing" and added that other initiatives — including the 100% clean energy bill, as well as other bills in his legislative package that would eliminate super pollutants, incentivize electric vehicles and construct carbon-free buildings — were likely stronger paths to eliminating greenhouse gas emissions.

"I don't think we should take carbon pricing off the table, but whether I propose it or not that remains to be seen," he said.

Washington joins the ranks of Hawaii, California, New Mexico, Puerto Rico and the District of Columbia in setting a 100% clean energy goal. Minnesota, Illinois, Nevada and New York, among others, are also considering increasing their renewable portfolio standards.