Newsletter Archive

New technologies allow farmers to turn animal waste into useful energy - addressing both environmental and energy needs while turning waste management costs into income.

Management of livestock manure is a serious environmental concern for America's farmers. Animal manure contains nitrogen, phosphorus and other nutrients that can react in the environment. When animal waste is used as fertilizer, or when waste management practices fail, those nutrients run off into the groundwater and can contaminate our nation's waterways.

In the 1970's, the Environmental Protection Agency (EPA) instituted regulations for livestock and poultry producers to ensure national standards for handling, storage, land application and disposal of animal manure. However, in recent years, market forces, technological changes, and regulatory influences have resulted in an increase in the number of confined animal feeding operations (CAFO), where livestock are kept and raised in a confined area. This unprecedented increase in CAFOs coupled with insufficient availability of cropland has led to the need for new solutions for animal waste management.

Federally funded R&D is now aggressively working to develop new and better technologies to convert animal waste into energy. Major technology areas at the U.S. Department of Energy (DOE) include:

• Dry animal waste is converted into steam or gas for the production of energy. This process allows the nutrients from animal waste such as nitrogen and phosphorus to be concentrated into ash and then transported safely from the facility.

• Manure with high moisture content is processed in an anaerobic digester and converted to a combustible methane gas. If managed properly, the methane gas recovered from this process can be used to directly produce electricity on a farm.

• Crops such as switchgrass, hybrid poplars, and willow can be developed to directly absorb all nutrients from the manure, which will prevent the nutrients from leaching into groundwater.

One DOE-supported project currently planned is the Multi-Farm Dairy Manure Digester in Tillamook County, Oregon. This project would address water quality problems related to the 160 dairy farms in the county, the Port of Tillamook Bay Municipal Corporation. It would involve a plug flow anaerobic digestion facility designed to process manure from 2,000 mature Holsteins from the local Tillamook Bay area. A truck would collect 35-40,000 gallons per day of manure. The digester would annually generate 2.6 million kilowatt-hours of power, 13,000 MMBtu of hot water per year, and 38,000 cubic yards of fiber [RCM and Mattocks, 4/18/01].

DOE-supported technology development efforts at West Virginia University are working to convert manure to a liquid resembling diesel fuel. To date, this project has been able to convert poultry litter to a liquid fuel and preliminary engine tests have shown that the fuel compares favorably to diesel fuel. It is anticipated that dairy, beef, and hog manure could also be converted to a diesel fuel substitute using the same technology.

Market and tax incentives are helping to drive the development of technologies that produce energy from animal waste. The U.S. Senate's proposed energy bill (S.1766) includes a national renewable portfolio standard that will allow retailers to obtain credits by generating power from renewable energy sources such as animal waste. Renewable portfolio standards, tax credits, and new and advanced technologies will continue to improve the economic viability of systems that produce electricity from animal waste.

At the state level, some states have already enacted, or are considering, renewable portfolio standards, which require a specific percentage of the power supplied by utility companies to come from renewable sources. Also, Minnesota, Ohio and other states are offering tax incentives to promote development of energy projects using animal waste. Some states, such as Iowa, Maine, and Texas, are enacting Net Metering Programs, which allow utility customers to generate their own electricity through alternative sources including animal waste, and then sell any excess power they produce back to the utility.

Systems that produce energy from biomass offer farmers the ability to generate additional revenue while reducing disposal and management cost. They also provide a new source of energy for on-site operations or for sale to the grid.

The result -- an increasing number of farmers are considering or are already installing energy-from-manure systems. In the 1990's, eighteen new farm-scale digester systems were installed at commercial livestock farms across the United States, which more than doubled the number of successful systems installed in prior years. As of 2001, there were 31 farm-scale digester systems in operation at commercial livestock farms, 23 of which are used to generate electrical power and heat.

Continued R&D at the Department of Energy and by industry should expand the technology opportunities for energy production from animal waste.

Minnesota ranks 19th in the nation in power generation from biomass. In 1999, nearly 1.3 million Mwh out of a total 49 million Mwh of electricity generated in the state came from biomass sources. Agriculture and forest products are among the industries in the state that are excellent sources of biomass material. In addition, animal waste from livestock and poultry operations will address a major waste disposal issue for Minnesota's farmers while offering new opportunities to produce energy.

A growing number of organizations in Minnesota are generating energy from animal waste.

• Minnesota is the number one turkey-producing state in the nation and ranks fifth overall in livestock production. Turkey manure was recently certified as a renewable energy resource in response to concerns from turkey farmers who hope to use animal waste as fuel for a power generating plant. Backers believe that turkey manure could be generating energy in the state as early as 2004.

• Minnesota hosts the Haubenschild Farm project, which has generated interest in energy circles for its digester. The project has produced thousands of dollars worth of energy in addition to reducing greenhouse gas emissions.

• The 2001 Legislature authorized an incentive payment of $0.015/kWh to new qualifying digester systems, which could push many otherwise marginal projects into profitability.

In addition to energy from animal waste, Minnesota is promoting energy production from other biomass sources:

• The Minnesota Department of Commerce funded a successful demonstration of the use of biofuel in over 15 diesel generators that provided the electricity for the Taste of Minnesota festival in St. Paul in 2000.

• In the 1980s, the disposal of municipal wastes in the state was a large environmental concern. The State Legislature tackled that concern by offering incentives for building combustors. Minnesota currently burns about a quarter of its municipal solid waste in municipal waste combustors.

• The Minnesota Valley Alfalfa Producers (MnVAP) is a farmer-owned cooperative focusing on gasification of alfalfa stems for electricity production and co-product marketing of pelletized alfalfa leaves as a high-protein animal feed. MnVAP is involved with several alfalfa processing facilities in southwestern Minnesota that will produce biomass fuel and value-added alfalfa products.

• To encourage alfalfa production for energy, the state has appropriated $200,000 to support development of the alfalfa production and processing capabilities, and approved favorable regulatory changes and personal property and sales tax exemptions (worth more than $3 million per year). In 1996, MnVAP purchased an existing alfalfa processing plant and designed, installed, and successfully operated the fractionation system to separate the alfalfa stems from leaf material. More than 50,000 tons of alfalfa were produced and processed by MnVAP in its first year of operation.

Finally, the wood and wood products, and pulp and paper sectors of the forest products industry produce valuable waste that can be turned directly into power or converted into new products. This combined with the many opportunities available in the agricultural and livestock industries ensure a promising future for biomass technologies in the state.

Minnesota Mandates Biodiesel Use
Minnesota has passed a law mandating that by June 2005 all diesel fuel sold in the state contain a 2-percent biodiesel blend. In the latest "Oil Crops Outlook" the USDA estimates that Minnesota may require 120 million pounds of soybean oil annually for biodiesel. Implementation of the Minnesota law could be accelerated upon development of adequate biodiesel production capacity within the state and enactment of a Federal excise tax credit. Although other fats and recycled oils can be substituted in biodiesel production, soybean oil may be the primary material initially. http://www.agweb.com

New Research Turns Sewage Farms Into Power Plants
Researchers at the University of Warwick's Warwick Process Technology Group have devised a process to extract very pure levels of hydrogen from wet bio-matter, such as sewage or paper mill waste. This pure hydrogen can then be used in fuel cells to power homes, factories and cars. Eventually the research team's "plated membrane reactors" could be built as small industrial units, no bigger than a large room in some cases, and added directly to the sites of sewage plants or paper mills. This process is clean, it produces no more CO₂ than would be produced naturally from the material biodegrading and it produces no other emissions such as nitrous oxides. http://www.spacedaily.com

Turning Wet Bio-Waste Into Energy
Scientists at the University of California, Riverside, are developing a way of converting "wet waste," such as sewage sludge and grass clippings, into synthetic diesel fuel and electricity. The research is funded by Riverside Public Utilities and Eastern Municipal Water District. The research is currently in the testing phase. If it is successful, a full-scale demonstration unit could be produced and operating by 2004. The five wastewater plants at Eastern Municipal Water District produce about 130 tons per day of biosolid waste. If just that waste were run through the new process, it could produce each day up to 26 barrels (1092 gallons) of synthetic diesel fuel and up to 34 megawatt-hours of electricity, enough power for about 3,000 homes. www.spacedaily.com

Perryton, TX Approves Grant For Fiberboard Plant
The Perryton, TX City Council voted to approve a $275,000 economic development grant that would bring a $200 million plant to town. All Fiber Group, an Atlanta-based firm, will build a facility that will manufacture fiberboard from wheat straw, process ethanol from corn, deliver food for livestock and grow hydroponic crops. The plant will produce about 130 jobs, and All Fiber Group expects construction to begin within 120 days. The facility will take in 30 million tons of wheat straw per year and produce 40 million square feet per year of fiberboard, which would be used for flooring and other construction uses. The ethanol plant will be a cutting-edge facility and will produce 100 million gallons of ethanol per year from corn. www.amarillonet.com

Data Sources:
OxyFuel News: Ethanol (U.S. Avg: Terminal); MTBE (Houston, TX: spot); Gasoline (Gulf Coast: spot, regular grade)
USDA-National Agricultural Statistics Service, "Agricultural Prices," "Grain Stocks"

Data Sources:
U.S. DOE-Energy Information Administration, "Petroleum Supply Monthly"
USDA-National Agricultural Statistics Service, "Agricultural Prices," "Grain Stocks"