Two Portland, OR-based utilities on Monday turned loose long-standing plans to expand natural gas storage capacity in the Pacific Northwest to service expanded gas-fired and renewable generation sources. The project involves a $128 million storage expansion.

Portland General Electric Co. (PGE) notified NW Natural it wants to proceed with its plans to provide long-term non-notice underground gas storage services to PGE's Beaver and Port Westward generating plants (see Daily GPIAug. 3). The expanded PGE gas-fired generation would integrate more wind power into its generation mix.

Under the new storage service, PGE will be able to draw on its gas resources from NW Natural's Mist facilities in Oregon to satisfy fueling needs and rapidly respond to changing conditions in wind generation, a NW Natural spokesperson said.

The project gained approval for an amendment to its existing site certificate from the Oregon Energy Facilities Siting Council in April this year, and NW Natural executives confirmed that the project is on track to be in service during the winter of 2018-19.

"Adding this storage service further enables us to adjust quickly when renewable energy -- such as wind and solar -- rise and fall with natural variability," said PGE CEO Jim Piro, noting that the project increases the electric system's reliability on peak-demand days. "This type of flexibility is essential as we move toward 50% renewable energy in our resource mix by 2040."

Under the NW Natural-PGE agreement, the northern section of Mist would be expanded to include a new 2.5 Bcf reservoir, along with an added compressor station with design capacity for nearly 120 MMcf/d and a 13-mile pipeline connecting the PGE generation plans at Port Westward and Beaver, near Clatskanie, OR.

New NW Natural CEO David Anderson called the storage expansion "an important project to support our region's move to more renewable power" while strengthening the grid at the same time. Anderson called the planned expansion "unique, no-notice storage services," noting it is supporting the effort to make the PGE generation plants more flexible.

NW Natural earlier this year obtained its Oregon Siting Council permit for the storage field expansion, and in May it released a request for proposals for contractors for the $128 million project. The company is still evaluating final bids that were gathered in June, he said during an earnings conference call in August.

Anderson assumed his new role heading the company this past summer, succeeding Gregg Kantor, who retired after holding the top job since 2009.