One Key to Energy Independence
Woody Biomass will play a roll in our energy future, but what that roll will be is still hazy
By Barbara Coyner
Investing in Technology
For example, Range Fuels, a cellulosic ethanol company founded by Khosla Ventures, will build its first ethanol plant in Georgia this year, with capacity to produce over one billion gallons of ethanol annually. Georgia pine is to be the renewable fuel source. And Chevron and Weyerhaeuser have combined their corporate clout to investigate cellulosic ethanol production on a broad scale.
Using woody biomass for energy is nothing new for the forest products industry. • Sawmills have long operated co-generation plants that provide ready energy for mill operations and also supply excess power to the grid.
Activity in the Woods In a remote corner of western Montana, foresters are now evaluating slash and burn versus biomass, considering whole tree yarding. Adding a few extra minutes to the processing time, the extra 15 feet of topwood is limbed and stacked in a separate pile. The tops are then valued with a different pricing formula.
Those working around the Fortine Ranger District have learned to modify contracts to reflect the handling of such material. The recovered wood goes to hew wood, Fuels for Schools, pellets, posts and poles, and pulp. Records show that by the end of April 2007, Region 1 of the Forest Service had sold 300,000 tons of slash, with 980 million pounds of slash-related carbon dioxide taken out of the atmosphere.
In Medford, Ore., the city is removing wood debris from its landfill and finding other similar sources, now generating 17 percent of its power from wood waste. Biomass One, a 25-megawatt power plant, furnishes energy to some 25,000 households per year, and an added powerhouse will take the capacity to 30 megawatts in the near future.
Behind the Medford energy project is a roster of new technology, including electrostatic precipitators that remove fine ash particles from the boiler exhaust stacks. Three Morbark 1200 tub grinders provide the muscle to pulverize the wood waste, with 650 horsepower engines and twelve-foot diameter tubs handling the mass.
Equipment Makes the Difference
John Deere recently showcased its new, three-machine woody biomass processing system at John Day, Ore. In the demonstration sequence, the first machine, a harvester, goes into the area and cuts small-diameter wood. Right then, the operator makes the decision on how to utilize the tree cutting it into logs, poles, or limbs and slash. A slash bundler follows a short time later, using a boom arm to gather up the limbs, small debris, and slash for biomass bundles. The bundler can pick up 200 to 400 pounds in one bite and feed it into a roller that then compresses it into a “log” wrapped in heavy twine, with the resulting log dropping out the back.
The third machine, a forwarder, uses a knuckle boom loader to pick up the bundles, load them on a trailer, and haul them out of the woods.
One bundle of biomass material, produced by the John Deere 1490D, can produce one megawatt of electric power, according to the company. Biomass in this form can store up to two years, plus the combustion problems associated with chips are minimized. Similar forest biomass technology has been at work in Europe for six or seven years, but with stepped-up
North American interest, the U.S. could pass Europe in the number of operating forest biomass machines in as little as three years, if the lack of viable biomass markets don’t limit the expansion. On the Montana front, woody biomass transportation has been front and center for Montana Community Development Corporation. This July, the organization and its partners sponsored a demo on another aspect of the roll-off bin and bunk concept, adding roll-off capabilities to a forwarder. The roll-off concept allows more agile equipment to trade bunks and bins around to transport small logs and woody biomass out of the woods more efficiently and at lower cost.
Don’t Celebrate Yet
Gee thinks the nation has to reward risk and reduce barriers, to invite industry and venture capitalists to participate. He also knows communities and environmental organizations have to be on board. “If you don’t have these, you don’t have a woody biomass project.” For the experts, location is key to making woody biomass plants pay off. The generation plant must be near:
One possible crimp in the idealistic win-win scenario advanced by woody biomass proponents is, “Who gets the woody biomass?”
Take the case of fiberboard plants that rely on sawdust and wood chips some are already feeling the pinch as energy production chomps into wood fiber supply. A large fiberboard plant uses 800 to 1,500 tons of raw wood fiber and sawdust each day. They are in direct competition with Oregon’s ten (and counting) industrial sites using woody biomass combustion boilers to power steam-driven generators that produce electricity.
When it comes to energy, things are changing quickly. But a couple of things are not likely to change soon. The U.S. will continue to focus on renewable energy as it breaks free of its dependence on foreign oil. And woody biomass will continue to be an option for the emerging technologies that can make use of it.