May 1, 2005

Bio-fuels picking up steam

Does it make sense to garner power from a source that will someday disappear, or would it be smarter to generate energy from a renewable source?

If you talk to Dr. Darwin Foster, a Texas Cooperative Extension forestry program leader, that is an easy answer because he sees a wood-fueled electricity generating plant in your future. In fact, he said that future could be sweeping west as some Scandinavian countries are already using wood to generate power.

"In Sweden, they're already bundling up what we're leaving in the forest after a timber harvest and using it as bio-fuel," Foster said.

"Bio-fuel" includes any renewable resource used to generate energy. As with ethanol distilled from small grain byproducts and methane from animal-waste, wood is another renewable energy source.

The key word is "renewable," Foster said. "As compared to fossil fuels which take hundreds of millennia to create and are not renewable," he said.

Using forest biomass, limbs, bark, and tree tops as bio-fuel has seen use in the U.S. wood product manufacturing companies already burn wood residue in steam boilers. The steam will drive electrical generators and supply part of the energy needed to run the plant.

Other mills use black liquor, a lignin-rich residue of the pulp and paper industry, for heat, steam, and electric power.

In both cases, a company makes the residue used at the plant during the manufacturing process. It is not recycled from the harvest site as many European countries do, Foster said.

The use of forest bio-fuel is not limited to energy production of forest industry plants. With prices of natural gas, crude oil, and other non-renewable sources rising, scientists are looking at using bio-fuels for residential consumption, Foster said.

Austin, Texas-based Green Mountain Energy is taking on that challenge as it uses wood residue to generate a part of the electricity it produces and sells to Austin area clients.

When a developer harvests a site in the U.S. and other countries, tree tops remain left behind. Though there is quite a bit of debris, developers consider these tops unusable, and they are left where they fall to bio-degrade or end up burning on site to speed up the process.

Science and economic studies say forest residue can be an economically viable energy source. What's required is for everyone involved in the forestry industry to rethink how they do things, Foster said.