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Green War Games

U.S. Navy's "great green fleet" uses biofuels in Pacific demonstrations

2 min read
Green War Games

The "world's largest maritime exercise" has a bit of an environmentally friendly sheen to it this year. The U.S. Navy unveiled its "Great Green Fleet" during the Rim of the Pacific (RIMPAC) war games this week, featuring fighter jets and several ships running on mixes of conventional fuel with various types of biofuels. The military has long been out in front of much of the U.S. government when it comes to energy initiatives, realizing early on that reducing the use of oil is a logical step to take for many reasons.

Secretary of the Navy Ray Mabus was on board the USS Nimitz on Wednesday, an aircraft carrier that took on 180 000 gallons of 50-50 fuel. The mix includes jet fuel along with algal oils and recycled cooking grease. Not, of course, to run the Nimitz itself -- the carrier is nuclear powered -- but for use in F/A-18E/F Super Hornets and other aircraft. Several other vessels, including the USS Chafee, the USS Chung Hoon, the USS Princeton, and the USNS Henry J Kaiser will also participate in the green fleet demonstration. The surface vessels will burn 350 000 gallons of a mixture of renewable diesel fuel and standard marine diesel.

Mabus has set a goal of getting fully 50 percent of the Navy's energy from "alternative sources" by 2020. Even more aggressively, by 2015 he wants the commercial vehicle fleet to reduce petroleum use by 50 percent. Such numbers would sound far-fetched in civilian life, but the military might be well suited to actually reaching these goals. There are still controversies over the actual environmental impacts of various types of biofuels, of course, and critics say the Navy's specific ideas are economically impossible, but it's a step in the right direction.

The demonstration going on right now in the waters near Hawaii is just a showcase for the viability of using alternative fuels in large-scale naval operations. RIMPAC, which dates back to 1971, includes 22 countries engaging in more than a month of war games exercises. More than 40 ships and submarines are involved, along with hundreds of aircraft and 25 000 military personnel. According to the Navy, the point of RIMPAC is to help "participants foster and sustain the cooperative relationships that are critical to ensuring the safety of sea lanes and security on the world's oceans," but at least for a few days and on a few ships it's also about transitioning to cleaner energy sources as well.

Image: Navy Secretary Ray Mabus observes transfer of biofuels to the USS Princeton during RIMPAC 20. Via US Navy.

The Conversation (0)
This photograph shows a car with the words “We Drive Solar” on the door, connected to a charging station. A windmill can be seen in the background.

The Dutch city of Utrecht is embracing vehicle-to-grid technology, an example of which is shown here—an EV connected to a bidirectional charger. The historic Rijn en Zon windmill provides a fitting background for this scene.

We Drive Solar

Hundreds of charging stations for electric vehicles dot Utrecht’s urban landscape in the Netherlands like little electric mushrooms. Unlike those you may have grown accustomed to seeing, many of these stations don’t just charge electric cars—they can also send power from vehicle batteries to the local utility grid for use by homes and businesses.

Debates over the feasibility and value of such vehicle-to-grid technology go back decades. Those arguments are not yet settled. But big automakers like Volkswagen, Nissan, and Hyundai have moved to produce the kinds of cars that can use such bidirectional chargers—alongside similar vehicle-to-home technology, whereby your car can power your house, say, during a blackout, as promoted by Ford with its new F-150 Lightning. Given the rapid uptake of electric vehicles, many people are thinking hard about how to make the best use of all that rolling battery power.

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