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Cargo ship plugs in at the Port of Oakland to reduce diesel emissions

on May 31, 2011

Gigantic 10-story tall ships that stretch three football fields long line the wharf at the Port of Oakland. There’s constant movement as big white cranes load and unload colorful shipping containers on and off the boats. Most of the ships look pretty much the same, equipped with lifeboats, pulley systems and flags hoisted on the decks. But one vessel has something different: two thick cables, which look like over-sized extension cords, that hang off the side of the boat and connect to the dock.

These cables are part of a new system called “cold-ironing,” which will reduce diesel emissions at the Port of Oakland. The first ship of its kind at the Port of Oakland, the APL Singapore, turned off its diesel engines on Friday and started using electricity to power the boat’s operations while dockside.

The state of California has mandated that half of all shipping company’s fleets must be able to cold-iron at all California ports by 2014. Currently, only a handful of ships in California have converted to cold-ironing and the APL Singapore is the only one that docks at the Port of Oakland to do it.

“Today we are announcing a clear air milestone,” said APL Americas President Gene Seroka at a press conference to unveil the boat’s new system last Friday. “APL will eliminate 50,000 pounds of nitrogen oxide here at the Port of Oakland, that’s what creates smog and that makes our air cleaner.”

While dockside, cargo ships need to stay powered to keep goods refrigerated and control electricity on the boat. That means they have to keep their diesel generators turned on, idling and burning fuel, the entire time they’re dockside, which is usually 24 hours. This creates smog, pollution and toxic soot.

“You can see there’s no diesel exhaust coming out of it,” said Seroka as he pointed over to the APL Singapore. “What we are announcing here today is the beginning of a new era on the Oakland waterfront… We will cold iron at every port call.”

APL is a Singapore-based container shipping line that works with 140 different ports around the world, including four on the west coast of the U.S. For the last two years, APL has been the Port of Oakland’s biggest customer. “If you walk into a Wal-Mart or Target or Macy’s, just about everything in there is coming in on a ship,” said Vincent Rankin, APL’s director of refrigerated sales. For export, he said that the U.S. ships out everything from lumber to grapes to chicken.

According to the North American Marine Environment Protection Association, 90 percent of the world’s goods travel by sea, so different protection agencies are looking into how to reduce and regulate this industry’s diesel emissions.

“We can balance economic growth and environmental protection,” said Anthony Eggert, assistant secretary for energy policy for the California Environmental Protection Agency, at Friday’s press conference. “These not need be mutually exclusive goals.”

Another benefit of reducing emissions at the Port of Oakland is cleaner air quality for local residents. Alameda County Supervisor Nate Miley, who also serves on the board for the Bay Area Air Quality Management District, said that cold-ironing will improve the health of people in West Oakland. “Pollution causes respiratory problems and aggravates asthma for those workers on board, on the dock and people in nearby neighborhoods,” he said at the press conference. “When we improve the quality of air we all are winners.”

But cold-ironing isn’t as simple as just plugging a ship in. Each vessel has to be completely retrofitted with cables, high-voltage transformers and upgraded power management systems. The dock also needs new infrastructure such as a substation with a transformer and switchgear and cables to connect to the public utility power grid. The Port of Oakland has just started a simultaneous project of building shore power connections at 12 of its berths.

The two cables that hang off the side of the ship bring in 6.6 kilovolts of electricity onto the boat, which is then transferred into 12 smaller cables that carry 460 volts and are wired to the ship’s main switchboard. The centerpiece of the whole system is a non-descript looking machine called the transformer, which weighs 16 tons and switches the kilovolts to volts. It’s housed in a yellow metal cage and is hung with signs that say “Danger, high voltage. Keep out.”

“If the diesel generators were on you’d hear them,” said Michael Saganey, the ship’s chief engineer noting the relative quiet while the ship was in port. Before cold-ironing, there were three auxiliary diesel generators that kept the ship running at dock. Not using the diesel engines on five of APL’s boats cuts 50,000 pounds of nitrogen oxide (a leading component of smog) and 1,500 pounds of particulate matter (soot) per year. In one 24-hour port call, that’s 1,000 pounds of nitrogen oxide and 30 pounds of particulate matter per boat that is eliminated.

APL has now retrofitted five of its ships for cold-ironing. The project took two years and cost $11 million. The company was awarded $4.8 million in grants from the California Air Resources Board and the Bay Area Air Quality Management District to do the retrofits both on the boat and at the port; APL paid for the remaining $6.2 million.

In addition to cold-ironing, APL is doing other environmentally focused projects on its fleet. For example, the company introduced low-sulfur fuel in ships that berth in Seattle, New York, Hong Kong and other ports, which is designed to reduce diesel emissions. The company is also purchasing bigger ships that carry more containers and will therefore have fewer ships out at sea; the APL Singapore carries 5,000 containers and the new ships will carry 10,000. Another project APL has started is “slow steaming,” which means slowing boats down from 22 knots to 18 knots while at sea—thus burning less fuel. “We are saving money and we are helping the environment,” said APL’s vice president of communications Mike Zampa.


  1. Brian on May 31, 2011 at 4:04 pm

    Nice bit of reporting there folks. Way to beat the majors to a big story.

  2. […] The first cargo ship to shut off its diesel generators and power off the grid docked in the Port of Oakland this week. California is now requiring that all shipping fleets be able to “cold iron” at California ports by 2014, but so far only a couple have met the standard. Idling ships typically run off diesel systems while docked for upwards of 24 hours, contributing significantly to ambient air pollution. Connecting instead to the electrical grid requires the upgrades to the vessels and new infrastructure on shore. [Read more – Oakland North]. […]

  3. […] Published May 31, 2011 on Oakland North […]

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