OAKLAND (CBS SF) — Port of Oakland officials said Friday they are encouraging more vessels to plug into the power grid while berthed to reduce emissions.

Port executive director Chris Lytle spoke recently with technical experts from five international shipping lines that are members of the Washington, D.C.-based World Shipping Council that visited Oakland to study shore power, known as “cold-ironing” in port vernacular.

By plugging in, ships can turn off their diesel engines while at berth. More than 70 percent of ships visiting the port use shore power, but Lytle said in a statement that “our goal is to plug in every vessel.”

Aerial View of Port of Oakland

A container ship docked at the Port of Oakland. (David Paul Morris via Getty Images)

He said port officials are trying to identify reasons why some ships don’t plug in, such as ill-equipped ships or a lack of electrical vaults on shore.

Port officials are considering various enhancements to increase shore power use, including adding electrical vaults, more substations, or standardizing the process for crews plugging in.

“If there are ways to strengthen our Port electrical

infrastructure to promote more use of electrical power from our grid, we will do it,” Lytle said. “We will collaborate with shipping lines and the marine terminal operators here in Oakland to build on the progress we’ve already made.”

The shore power program, which started at the Port of Oakland in 2012, has helped reduce diesel emissions at the port by 75 percent in the past decade, port officials said.

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