Power Without the Burn
Biodiesel is packed with power. Burning it in an engine is just one way of extracting its energy. Washington-based Innovatek Inc. has come up with an alternative to get at biodiesel's energy-a hand-sized processor that could make biodiesel a hot commodity in the electricity generation market.
Fuel cells capture electricity from chemical reactions, somewhat like a battery. Unlike a battery, fuel cells run off a fuel-hydrogen-and oxygen from the air, and can produce electricity as long as the hydrogen is flowing. Fuel cells are nearly silent and don't produce any exhaust except water. Fuel cells are also efficient at turning chemical energy into electrical energy, says Patricia Irving, president, chief executive officer and founder of Innovatek Inc. "Fuel cells have been receiving a lot of attention because they are more efficient than conventional technology," Irving says. "Fuel cells operate differently than internal combustion engines and therefore do not have those efficiency losses."
The downside of fuel cells is that until recently, they were expensive. This limited their use to specialized applications, such as powering space craft including the shuttle and the International Space Station. However, with research and innovative manufacturing techniques the price of fuel cells has fallen to the point where they are competitive in many applications including replacing batteries in back-up power systems. "Fuel cells are being used all over right now," Irving says. "They could be used more than they are now if a source of hydrogen could be made more available. They are being used now, but they have many, many, many more potential markets in the future."
Fueling the cells, however, remains problematic. Hydrogen must be stored at high pressure to be economical, and is explosive when released. Most hydrogen is also manufactured from natural gas, meaning that ultimately it's not a carbon-neutral fuel.
One way to solve the problem of transporting and storing hydrogen is to make it on the spot. The process for making hydrogen is fairly straightforward. A hydrocarbon is heated with steam at high pressure and temperature to form hydrogen and carbon dioxide, a process called steam reforming. Usually this is done in large production plants. "What Innovatek has done is scale that plant-that large plant-down to something that is actually portable," Irving says.
Innovatek's device is called the InnovaGen fuel processor. It uses microscopic channels and proprietary catalysts to continuously produce hydrogen from a variety of hydrocarbon sources. "Rather than natural gas, which is something we can also use, we have been focusing on liquid fuels," Irving says. "That includes things like biodiesel, vegetable oil and other renewables."
The fuel processor works by combining two feeds, one of a hydrocarbon and the other of water, in a catalytic reactor. "We use microtechnology to scale down the system into something that can be held in your hand, and produce hydrogen that can be fed directly into the fuel cell," Irving says. "Rather than using a huge plant that produces hydrogen that is compressed into cylinders, our device can be integrated directly into the fuel cell as a component of an overall system."
Using renewable sources of hydrogen makes the technology more environmentally friendly. "Depending on where the hydrogen gas comes from, over its life cycle the system still may produce pollutant gases," Irving says. "That's where biodiesel comes in. Innovatek's main philosophy is sustainability. We have been in business for 10 years now and that was our goal from the start. That goal of sustainability requires renewables. Our future objective is to see our reformers used with renewable fuels like vegetable oils and biodiesel."
Fuel cells can operate at many different scales, from portable devices to equipment that's large enough to power an industrial facility. Irving says the InnovaGen can provide fuel for just about any size application, but the company is focused on smaller applications. "The focus of our work has been more in the range of 1 kilowatt to about 50 kilowatts," Irving says. "Because of our microchannel technology our competitive advantage is in applications that require small footprints or portability. We can scale up in much the way computers now scale up, by adding to the number of microchips rather than making the unit bigger and bigger. We just add more microchannels to scale up the system."
By using liquid fuels, the fuel processor makes fuel cells practical in places far from the plants that produce commercial compressed hydrogen. "Getting hydrogen to the point of use is an issue," Irving says. "Right now that is done by using trucks to haul the compressed gas cylinders. With a liquid fuel like biodiesel, the fuel can be transported using our existing infrastructure just like gasoline and diesel fuel." Irving adds that liquid fuels have a much higher energy density than a compressed gas such as hydrogen, that is, the same volume of biodiesel can generate more electricity than a similar volume of hydrogen. A higher energy density means that the transportation costs for the fuel to generate a given amount of electricity are lower.
Even among liquid fuels there are significant differences that favor biofuels, Irving says. Fossil fuels such as gasoline and diesel fuel contain impurities that can degrade the catalyst in the fuel processor. The main culprit in catalyst degradation is sulfur. Biodiesel contains lower levels of sulfur than even ultra-low sulfur diesel. "For us, using biodiesel is less challenging," Irving says. "We love working with renewable fuels. Our catalyst works better with biodiesel than with regular fossil-based diesel fuel." Biodiesel is also nontoxic, she adds, so that even in the event of a spill the clean up is simpler than cleaning up fossil-based diesel.
A growing market for fuel cell technology is as back-up power for vital facilities such as hospitals. Generators running on diesel engines can be loud and release noxious fumes, while fuel cells are silent and odorless, Irving says. Another potential market is the military. Innovatek has been working to adapt its fuel processor to work with jet fuel (JP-8). "We have been encouraging the Navy, which funded us, to develop a reformer for JP-8, to very seriously consider biofuels as one of their sources of fuels," Irving says. "They are moving in that direction. So the Navy is seriously looking at converting some of its operations to biodiesel fuel."
Innovatek has been using biodiesel provided by Imperium Renewables Inc. Both companies are based in Washington state. Irving sees a bright future for the combination of renewable fuels and high technology, especially if the biodiesel industry can wean itself from feedstocks that have food uses. "I think it is crucial for the biodiesel industry to realize that they have to move beyond soybeans," she says. "Soy can be one of the sources, but the industry needs to move beyond that in order for the markets to be viable." n
Jerry W. Kram is a Biodiesel Magazine staff writer. Reach him at email@example.com or (701) 738-4962.