Sustainable energy for Interior villages?

Nancy Fresco and her child in the taiga.

While researching carbon dynamics for her doctoral dissertation with SNRAS in the IGERT program, Nancy Fresco (now with SNAP) found a way to assist rural Alaska communities in solving their energy needs.

Studying ways the state could become more carbon neutral, Fresco stumbled on biomass conversion, which could change the way villages create electricity. By harvesting sustainable timber that only takes dozens of years to replace, rather than the millions of years required for oil and gas, not only is the carbon footprint smaller but the benefits on the side are numerous. “The potential is huge for communities to become more independent from fossil fuels and from the vagaries of the market and to become more self-sufficient,” Fresco said.

Stressing that she speaks from an academic perspective and has not visited the possible sites, Fresco noted that each village is different and could make the proposal work only on a case by case basis. “Whether this would be desirable is up to the communities. It’s an option.”

Converting electrical power generation systems to wood energy could play a significant role in addressing the high cost of electrical generation, wildfire risk, unemployment, and environmental contamination from diesel fuel, Fresco asserts. Under the direction of UAF Professor F. Stuart Chapin III, she assessed the feasibility of switching power generation systems in 33 rural communities in forested regions of interior Alaska and discovered that all but one of those communities could meet all their electrical demand and some heating needs with a sustainable harvest of biomass within a radius of eight kilometers of the village.

Black spruce, Picea mariana, along the Copper River. Photo  from NOAA.

The focus of the study was on black spruce that could be burned in simple, easily maintained small-scale boilers to generate electrical power. Whole-tree wood chips or chunks were oxidized with excess air circulation and the hot flue gases released produce steam in the heat-exchange sections of the boiler. Fresco and Chapin assumed an efficiency of 28 percent for electrical production, keeping their estimates intentionally conservative. They took into consideration the installed cost of a biomass power system per kilowatt of generation capacity, the total biomass capacity installed, the actual energy offset, diesel efficiency, diesel price, the fraction of nonfuel costs offset by use of biomass, total nonfuel costs, biomass energy generated, and biomass energy costs. The installation costs could be recouped within 12 years.

“Biomass fuels are likely to increase the long-term social and ecological resilience of village communities to externally-driven changes, including fluctuations in fossil fuels prices, variability in Alaska’s economic outlook, and changes in fire risk and fire management,” Fresco said.

Social factors likely to affect the feasibility of fuel substitution included:

• Existing social infrastructure related to village electrical utility management and funding, fire prevention, and biomass harvest;
• Threshold requirements (make-or-break factors needed within a particular community or at a broader scale, e.g., a minimum level of local technological expertise);
• Existing institutional barriers to change;
• Potential positive social feedback (e.g., autonomy, employment);
• Potential negative social feedback (e.g., reactions to system quirks or failures);
• Lessons learned from existing biomass projects in rural Alaska.

Further reading:

• “Biomass fuels: local energy, local jobs, and community resilience,” by Nancy Fresco and F. Stuart Chapin III, Agroborealis 40.1, Spring 2009 (in press).

• Researcher seeks energy answer in biofuels, SNRAS Science & News, October 28, 2008.