Biomass
Overview
Bioenergy is a collective term for renewable energy made from the organic material of recently deceased plants or animals. Sources of bioenergy are called “biomass” and include agricultural and forestry residues, municipal solid wastes, industrial wastes, and terrestrial and aquatic crops grown solely for energy purposes. Bioenergy includes the generation of energy from biological sources such as landfill gas and the combustion of organic fuels to produce electricity or heat. Although oil and natural gas are energy sources derived from deceased plants and animals, they are not considered biomass because their organic material has not been a part of the carbon cycle for millions of years.
Biomass is an attractive petroleum alternative because, developed responsibly, it is a renewable resource that is more evenly distributed over the Earth’s surface than finite energy sources, and may be exploited using more environmentally friendly technologies. It is also considered “carbon neutral,” meaning the carbon absorbed during the lifespan of the organisms from which it was created counters the carbon released by the combustion of the biofuel. Today, biomass resources are used to generate electricity and power and to produce liquid transportation fuels, such as ethanol and biodiesel. Ethanol is the most widely used biofuel. Currently, a majority of ethanol in the United States is made from corn, but new technologies are being developed to make cellulosic ethanol from a wide range of agricultural and forestry resources, including organic waste byproducts such as sawdust or cornhusks. In Alaska, primary biomass fuels are wood, sawmill wastes, fish byproducts, and municipal waste, though there is also some potential to grow energy crops such as canola for biofuel development.
Waste wood and sawdust
- Wood chips for use in the Craig boiler. (City of Craig)
With 11.9 million acres of productive forestland (forest not in Park or Wilderness areas) and the ability to grow up to 3.5 million cords of wood a year, Alaska has the potential to develop a biomass industry that could supply abundant, cheap power to many towns. Wood is already an important renewable energy source for Alaskans, with over 100,000 cords per year used for space heating statewide. Alaska’s waste wood and wood products could provide an excellent source of fuel to help lower heating costs in many Alaskan communities. An estimated 2.3 million acres of forests in Alaska have been impacted by bark beetle infestations, and thinning of these forests is necessary for overall forest health.
Closure of the major pulp mills in Sitka and Ketchikan in the 1990s ended large-scale wood-fired power generation in Alaska. However, the price of oil has raised interest in using sawdust and wood wastes as fuel for lumber drying, space heating, and small-scale power production. In 2008, the City of Craig installed a sawmill waste-fired boiler to heat the city pool building, pool water, and school buildings. The boiler will save the city an estimated $120,000 per year and displace about 19,000 gallons of oil and 33,000 gallons of propane. Additional wood-fired boilers have been installed in Kasilof and Tanana, and over 15 projects in other communities are under development. Alaska has also seen renewed interest in converting low-value wood and wood wastes to liquid fuels such as ethanol, though further technological development is necessary before this use of wood waste becomes a possibility.
Biodiesel
Alaska’s pollock fishing industry produces about 21 million gallons of oil every year and about 8 million gallons of it is used to displace diesel used in electric generators and boilers at seafood processing plants. The Alaska Energy Authority estimates that an additional 13 million gallons is dumped into the sea each year in the form of unprocessed fish waste. The Alaska Energy Authority has partnered with fish processor UniSea Inc. to test the use of fish oil diesel blends in electric power generation in a 2.2 MW generator. UniSea now uses around 1 million gallons of up to 70% fish oil for electricity production each year in their Unalaska facility. Currently all processing of the fish oil into biodiesel is outsourced to a commercial facility in Hawaii. The Alaska Energy Authority hopes to use data from UniSea Inc’s trial generator to determine if a commercial biodiesel processing facility is feasible in Alaska.
Several groups in population centers throughout Alaska work to make traditional waste vegetable oil biodiesel available to a larger group of people. The Alaska Biodiesel and Straight Vegetable Oil (SVO) Network operates in Southcentral Alaska and provides resources and classes for people interested in making biodiesel or converting their cars to run on SVO. The Fairbanks Biodiesel Cooperative is a young cooperative that is currently limited to 10 members, but may provide the same services for the interior in the near future. Due to the fact that biodiesel solidifies at around 32 °F, the Alaskan cooperatives only operate during the summer. New technologies may change that in the near future. The Indiana Soybean Alliance recently conducted a successful test run of their Permaflo biodiesel, which has a gel point of approximately -67°F. In early March 2009, a group of scientists drove two vehicles from Anchorage to Fairbanks using the Permaflo technology.
At this time, the availability of used vegetable oil in Southcentral Alaska is limited. Until March 1, 2009, Alaska Mill and Feed sold cleaned vegetable oil recycled from local restaurants to be used in SVO vehicles or converted into biodiesel. Alaska Waste has taken over contracts for the removal of used vegetable oil from large restaurants for its own 500,000-gallon capacity biodiesel plant, scheduled to begin operation in 2009. Alaska Waste does not plan to sell the biodiesel produced at the plant, but rather will use it to fuel their own vehicle fleet. Anchorage biodiesel advocates are currently looking for alternative sources of waste oil.
Municipal Waste
Alaskans produce about 650,000 tons of garbage annually and have seven class I landfills (landfills that accept 20 tons or more solid waste daily) throughout the state. From 1997-2007, Eielson Air Force Base near Fairbanks used 600-3000 tons of densified paper from the Fairbanks landfill annually to co-burn with coal, producing up to 1.5% of the base’s heat and power. Chena Power currently plans to build a 400 kW biomass powerplant at the Fairbanks North Star Borough landfill that would run off of 5,000 tons of waste paper, cardboard, and land waste annually. Conventional recycling of paper, which comprises about half of Fairbanks waste stream, is economically marginal given the distance to Lower 48 markets.
Methane gas produced as a by-product of landfills can also be used to produce electricity. According to a report prepared in 2005 for the Municipality of Anchorage, energy recovery from the Anchorage landfill would capture methane with an energy equivalent of approximately 1.9 million gallons of diesel annually over the next ten years, the equivalent of about 2.5MW of electrical power.
Sources:
Alaska Energy Authority
Department of Energy Office of Energy Efficiency and Renewable Energy
City of Craig
Chena Hot Springs
Alaska Biodiesel and SVO Network
“Landfill Gas Utilization Economic Evaluation for Anchorage Regional Landfill”
Further resources:
Alaska Biodiesel and SVO Network (Southcentral)
Alaska Biofuels Alliance, call Jonathan Kamler at 790-1049 (Juneau)
