While growing biofuels feedstocks on farms is becoming commonplace, actually making biofuels on the farm is fairly rare. Pacific Northwest efforts to develop advanced technologies for farm-scale production illustrate significant potential to produce fuels from local feedstocks for local use.

An agricultural residues project is being developed by Farm Power, a nonprofit dedicated to promoting farm-scale bioenergy production, partnered with USDA Agricultural Research Service. In a federal bioenergy research complex heavily focused on large-scale technologies, ARS is a welcome oasis for community-based bioenergy development.

ARS has conducted some first-order studies looking at biofuels potential of Northwest residues. But the challenge is that these feedstocks have low energy density and a certain amount must be left on the soil to preserve fertility. So ARS is interested in smaller-scale technologies that are less hungry.

The Farm Power project at Rockport, Washington a few miles south of Spokane fits the bill. It employs technology developed at ARS Western Research Institute using heat to convert biomass into energy gas. The project aims to make this a commercially replicable technology while assessing the agronomic and economic practicalities of using residues. The gasifier will be fed with residues from Kentucky bluegrass seed. This is a significant crop in the area, and farmers who can no longer burn fields due to air pollution restrictions need to find new ways to dispose of the residue.

"Within five miles there are 5,000 acres of Kentucky bluegrass," notes project manager Jack Zimmer. "That's plenty of straw to keep this thing going. When we have this unit done, it can feed itself from a 2,000-acre farm."

"Huge projects are fine," Zimmer adds. "But there are lots of biomass materials that can be used to produce energy that are readily available and do not have to be moved long distances. If you are not having to haul feedstock from 20-40 miles away, it becomes more viable."

Farm Power plans to place the gasifier on line by the end of 2007, process around 2,400 pounds of biomass per day and use the gas to run an electrical generator. Inland Power has agreed to take the surplus.

These projects underscore how biofuels production at the farm and community scale generates many environmental and economic benefits.

Community benefits--Corporate ownership of biofuels plants by large agribusiness corporations has raised criticism about who is gaining most of the benefits from this growing industry. While biofuels plants at any scale generate local economic benefits, local ownership keeps more of the money circulating closer to home. In developing nations, where concerns whether small farmers will actually benefit from bioenergy are greatest, farm-scale technologies could be hugely important.

Use of residues--Employing materials that now pose waste disposal problems is one way to increase biofuels production without competing with existing crops and markets. However, collecting enough residues to support a large-scale plant demands a substantial supply. Plants will also likely require fairly consistent material. So residues that exist in smaller quantities may not find a use in large-scale operations, but could readily feed farm-scale technologies. The proximity of farm fields to production has another crucial advantage--byproducts of production containing soil nutrients can be quickly sent back to the land to maintain fertility. Farm Power will do this with gasifier ash.

Transportation--Shipping biofuel feedstocks represents a major share of the energy employed to make biofuels, and thus is a global warming pollution contributor. So shortening transport distances improves the energy and pollution-reduction performance of biofuels.

Unlike the current petroleum-based system, biofuels will not grow in a "one size fits all" fashion. A diversity of feedstocks and markets will characterize biofuel growth, including small local feedstock streams that can readily supply community fuel demands. That is why work being done by outfits like Farm Power and ARS is vitally important to realize the farm-scale opportunity.

--Patrick Mazza, Climate Solutions Research Director. This is an edited article from a series available on http://www.climatesolutions.org. See website for full version.