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This article is from the In-Depth Report Alternative Energy and the Future of Our Fuels

First Dedicated Biorefinery Could Wean Hawaii Off Imported Oil

New technology converts all kinds of plant waste into usable fuel--and is part of a growing array of technologies aimed at island energy independence
hawaii-biorefinery



Courtesy of Honeywell / UOP

On former pineapple fields outside of Honolulu, an industrial tube has been erected, ensconced in a steel scaffold. Dwarfed by the nearby oil refinery, the modest tube represents an attempt to one day wean Hawaii from imported oil. It is the nation's first dedicated biorefinery, employing high heat to turn plant matter into oil, followed by chemical catalysis to upgrade that oil into a usable fuel, just like the much larger refinery down the road.

The biorefinery "makes a fuel which is usable in generator sets, boilers and also possibly in marine engines," says chemical engineer Jim Rekoske, vice president of renewable energy and chemicals at Honeywell's UOP, the company responsible for building and operating the facility. By next year, UOP hopes to have the full biorefinery in place, which will be able to make almost any transportation fuel.

As the company has demonstrated elsewhere in the world, it is possible to make jet fuel from plant oils—whether they come from jatropha seeds, the flowering weed camelina or any other oil-producing plant. The same is true for other forms of transportation fuel, whether corn ethanol for cars or algal oil to power ships. The new facility in Hawaii will be the first integrated biorefinery dedicated to churning out bio-based versions of the full range of fuels more commonly made from petroleum.

Island state
Hawaii relies almost entirely on oil for its energy, whether it be gasoline for its cars, jet fuel for the planes that shuttle tourists in and out or even heavier oil to burn in its power plants. All of that oil comes in by supertanker, and even the island's most defensive inhabitant—the U.S. military—is nearly completely reliant on shipped-in fuel. All told, the state imports 45 million barrels of oil a year, nearly a third of which goes to run power plants.

The new biorefinery is a first step to changing that. It will take in biomass—the generic term for the leaves, stems and other bits of plants not typically used for food for humans and livestock. That will include inedible components of Hawaiian crops, such as macadamia nuts and sugarcane, as well as guinea grass and eucalyptus. The oil-rich jatropha plant and other so-called "energy crops" being grown on the island may also pass through the industrial plant, as long as growers are willing to part with it for free (though that may prove unlikely). "We're going to use whatever we can get our hands on," Rekoske says, in a bid to demonstrate the flexibility of the technology. 

The biomass is ground into tiny bits and dried to drive out the water that can make up as much as half of the weight of fresh plant material. The plant flecks fly through the tube where ordinary sand heated to 500 degrees Celsius flashes them to an oil vapor in less than 800 milliseconds in a process called pyrolysis. What is left is the sand and the bits of biomass that cannot be vaporized, such as various salts and some residual char. The vapor exits and the solid bits drop to the bottom, where the char is burned to reheat the sand. "There is enough heat in the combustion of the char to heat the sand up to a high enough temperature to run the pyrolysis," Rekoske claims.

The oil vapor, meanwhile, is condensed into a liquid fuel, which is then further upgraded and processed to make a green fuel similar to the bunker fuel that is used in cargo ship engines and industrial boilers, for example, except it lacks the pollution-causing sulfur common to the bunker fuel refined from petroleum. Potential partners thus range from the U.S. Pacific Command (USPC), based in Honolulu, to local electricity cooperatives. And next year, when the full biorefinery is complete, UOP will be able to make everything from gasoline to jet fuel. "The idea is to make a whole barrel of product out of the biorefinery," Rekoske says.

At present, the new biorefinery is expected to churn out five barrels a day, which, thanks to rules attached to the $25-million U.S. Department of Energy (DOE) grant that made the project possible, will be free to anyone who wishes to test the biofuel. Ultimately, this facility may be able to convert as much as 1,000 metric tons of biomass per day into liquid fuel; the goal is to build a commercial-scale facility that would churn out 50 million gallons (189.2 million liters) of transportation fuels per year.

Yet even an output of that scale would only account for 1/45 of Hawaii's annual oil use. To really make a dent, the state would have to build many such facilities—and grow much more biomass, though that is at least a feasible undertaking, given current land availability. The islands now boast some 400,000 acres (161,874 hectares) of fallow land (though more and more of that is being taken up by biotech test crops). The other alternative is more condominiums, which may ultimately prove fatal to attempts to revive Hawaiian agriculture. "This is a tremendous opportunity to make a product, which is in demand in Hawaii, which is expensive in Hawaii, from land that is not being productively used," Rekoske argues. This, in fact, is part of the reason the company located there rather than competing on the mainland with cellulosic ethanol makers for corn stover or the like.

Of course, the biorefinery is just part of Hawaii's efforts to wean itself from imported oil.  Other measures range from the military running a test fleet of hydrogen fuel cell vehicles from General Motors to burning trash to produce electricity to help feed the electric car–charging stations beginning to appear across Honolulu. Hawaii even has an ongoing effort to turn ocean thermal energy conversion technology into a reality, as well as an actual algal agriculture industry—the algae are largely grown for nutraceutical purposes but have also been turned into jet fuel on the mainland by UOP.

Naval force
The biggest user of oil on the islands—and possibly the entire world—is the U.S. military, which burns through more than 300,000 barrels a day, worldwide. In Hawaii, all of that oil is imported. As a result, the USPC has taken a keen interest in diversifying its supply of fuels, and the U.S. Department of Defense as a whole has pressed for plans to invest $510 million with the DOE and Department of Agriculture to help commercial development of a domestic biofuels industry. "We would never let countries that sell us fossil fuels build our military vehicles, but we give them a say in whether they operate," U.S. Secretary of the Navy Ray Mabus said at the Bloomberg New Energy Finance Summit on March 20. The Navy has embraced biofuels that can immediately substitute for petroleum in conventional engines, "mainly to make us better war fighters," Mabus said.

That switch has received criticism, largely because such alternative fuels are more than 10 times more expensive than petroleum-derived fuels. "From wind to coal and coal to oil to nuclear, there have always been naysayers," said Mabus, recalling previous Navy efforts to switch motive fuels. As it stands, however, the Navy has spent more than $5 billion more than budgeted in the past year just on oil and it has set a goal of securing half its fuel needs from biofuels by 2020.

The Navy's effort extends beyond just biofuels, of course, and includes projects such as lightening loads for U.S. marines by using solar cells to replace heavy batteries. "When you think of a marine, the first thing you think of is probably not an ardent environmentalist," Mabus noted. "They truly have embraced this" because it saves lives. Indeed, for every 50 fuel convoys in Afghanistan, one marine dies.

This July the Navy intends to demonstrate a "Great Green Fleet" in Hawaii, which will include a nuclear-powered carrier and submarine but also all aircraft and surface ships burning a 50-50 blend of biofuels and petroleum-derived fuels. It is a bid to demonstrate that the U.S. Navy can power its vehicles with more secure domestic biofuels that also happen to reduce the greenhouse gas emissions causing climate change. Already, the USS Ford has cruised from Washington State to San Diego on a 50-50 blend of marine diesel and biodiesel, among other demonstrations in recent years.

That type of fuel is exactly what UOP aims to provide in the long run. "The idea is to demonstrate that the combination of our pyrolysis and our upgrading technology provides superior economic returns for people who own biomass and want to turn it into transportation fuels," Rekoske says—an effort that could be useful on other islands or even the U.S. mainland. "We'll show the world this ravenous teenager of a technology we have that can eat anything and turn it into transportation fuel."

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