JUNCTION CITY — Shell Oil Products U.S. is expanding its New Energies facility in Junction City to produce renewable natural gas.

The company also announced plans for two more facilities at dairies in Idaho and Kansas.

The facility in Oregon uses cow manure and straw to produce 736,000 million Btu a year of renewable natural gas.

The expansion added six anaerobic digesters, changing the feedstock from food waste to manure and straw and replacing the biogas-fired electrical generator with a gas upgrading system.

The new RNG production facilities are the Shell Downstream Galloway at the High Plains Ponderosa Dairy in Plains, Kan., and Shell Downstream Bovarius at the Bettencourt Dairies in Wendell, Idaho.

Together, the two RNG facilities will produce approximately 900,000 million Btu a year of renewable natural gas.

The company does not disclose the specifics of the arrangements, including how much the dairies are paid and the relationships with the dairy farmers.

The byproduct of its manure-based biogas production depends on the facility and the needs of the dairy operations, according to the company. For the Junction City operation, the byproduct is fertilizer.

The RNG produced at the Shell facilities enters the pipeline and is commingled with the natural gas supply.

In the case of Junction City, Shell is selling the natural gas to the Northwest Natural gas utility.

Shell wouldn’t comment on future plans for additional manure-based biogas facilities or partnerships with dairies.

“Portfolio shaping is an ongoing process within Shell businesses to ensure we have the right mix of assets to deliver maximum value to our shareholders and deliver on our business strategy,” the company said.