Grassland buffers protect Wisconsin’s waterways from excess nutrient runoff from agriculture. Photo: Anonymous.
Bioenergy? production requires the flow of biomass? material from the land to its eventual end use. Along the way, biomass passes through a series of processes in what is called the biomass supply chain?.
Various segments of the biomass supply chain require unique sets of knowledge, technology and activity. These include growing, harvesting, transporting, aggregating, storing and converting biomass. Additionally, and depending on the biomass type and the conversion technology used, pre-processing may also be a necessary step along the pathway from the land to energy use.
Transport, storage and handling are key issues throughout the supply chain and link the various segments to each other (figure 1). The various stages along the biomass supply chain are frequently interdependent and interconnected, with changes in productivity and technology in one stage effecting that in other stages.
CLICK ON THE SUPPLY CHAIN MENU ABOVE TO EXPLORE THE VARIOUS STAGES ALONG THE PATH FROM LAND TO CONSUMER.
Additional key issues are of concern within specific segments of the supply chain. For producers key issues include crop selection, achieving sustainability, and improving farm profitability (see More). For pre-processing there are issues of scale? of operation and whether to approach pre-processing as an opportunity for on-farm added value to biomass, or to approach pre-processing as an opportunity for a new, separate industry (see More). A major issue in conversion of biomass is scale-up of cellulosic biofuel? technology (see More). Among consumers, key issues are availability, affordability and ease of use of bioenergy (see More)..
Currently in Wisconsin, biomass markets for bioenergy are limited and somewhat fragmented. Woody biomass is the primary feedstock? used for biopower? in Wisconsin. Corn grain is the only feedstock currently used for commercial production of biofuel and soybeans are the primary feedstock for biodiesel in the state. Nonetheless, use of perennial herbaceous feedstocks is being promoted through publically funded research (see Great Lakes Bioenergy Research Center), entrepreneurial activities of private companies (see for e.g., Agrecol), and pilot projects with private or public support (see for e.g., Nelson Dewey Generating Station). These efforts could lead to markets in the future. However, market certainty is not guaranteed (see the Chicken and Egg Dilemma). But as producers and businesses continue to express interest in bioenergy, momentum continues to build for creating and developing grassland- and agriculture-based biomass markets (see for e.g., more).
In Wisconsin, there are two main bioenergy markets: biopower (electricity and heat/steam) and processing plants that convert biomass to ethanol. Biopower facilities within the state currently utilize forest-based and waste-based biomass. The Nelson Dewey Generating Station recently acquired permits for test-burns that will include agriculture- and grassland-based biomass. All of the commercial-scale processors of ethanol in Wisconsin are corn grain-based, and one pilot project is converting sawmill wastes (e.g., sawdust) to ethanol. Corn grain production for ethanol is typically done under contract with on-farm storage for delivery at a specified date, although other arrangements are possible. Of course, grain producers may also sell on spot markets. However, these exchange instruments do not yet exist for non-forest cellulosic materials in Wisconsin.
As non-forest cellulosic bioenergy develops in Wisconsin and the Midwest, it may be possible to buy and sell biomass through Craigslist-type on-line tools, brokers, or commodity exchange systems. Craigslist-type exchange can occur between individual buyers and sellers who negotiate their own terms of exchange (see for e.g., North American Biomass Exchange, Minneapolis Biomass Exchange). Brokers work on a commission-basis to connect seller and buyer (see for e.g., BiomassXchange, and AtmosClear). The Biomass Commodity Exchange project is currently working to develop a formal commodity exchange system. Since commodity systems do not yet exist in the Midwest, however, Wisconsin producers of herbaceous cellulosic biomass who do not have a contract with a conversion facility must locate a buyer themselves via on-line tools or they must use a consultant to locate a potential buyer.
Planning and continual operation of a bioenergy project requires steady and reliable supply of biomass. Reliability of supply can be influence by biomass purchase agreements (as described above) and through logistical planning. Logistical planning is necessary for overcoming challenges of storage, handling and transportation. Bioenergy projects require feedstock throughout the year, although non-forest biomass is grown only during limited growing seasons annually. Therefore, biomass must be stored for later use. Feedstock must meet quality and moisture content specifications which should be assessed upon delivery to ensure efficient conversion and fair payment. These biomass characteristics will be affected by storage method. Feedstock must be handled and transported as it is moved along the supply chain. Handling and transportation must be done as cheaply as possible to limit overall costs of bioenergy. Because of its low bulk density biomass must be densified to reduce transportation costs (see Densification). Other pre-processing may be necessary to transform biomass into more suitable forms for specific conversion technologies.
The public image of biomass production and conversion into bioenergy is contentious in many locations. To improve the likelihood of stakeholder support, and therefore project success, it is essential that bioenergy projects consider environmental and social impacts, and seek the input of stakeholders (figure 2). Bioenergy developers, producers and community stakeholders should address these questions:
- What types of and amounts of biomass resources are available and can be produced sustainably?
- Are there competing uses for this biomass and would its use for energy impact other end uses?
- What supply chain (and corresponding conversion technology) developments available now, or in the future, will enable environmentally acceptable bioenergy products?
- What impacts will the increasing use of biomass in a regional have on the local environment, water supplies, and local economies and communities?
- Will there be beneficial social issues such as employment, rural development, improved health, improved equity, and opportunities for increased skills and knowledge of producers?
- Will there be opportunities for innovation on behalf of various participants in the supply chain?
International Energy Agency. 2007. Good practice guidelines: bioenergy project development & biomass supply. Organization for Economic Co-operation and Development (OECD). Paris, France. Available at: http://www.iea.org/publications/freepublications/publication/biomass.pdf; verified Jan. 8, 2013.
Leboreiro J and AK Hilaly. 2011. Biomass transportation model and optimum plant size for the production of ethanol. Bioresource Technology 102:2712-2723.
Rentizelas, AA, AJ Tolis and IP Tatsiopoulos. 2009. Logistics issues of biomass: the storage problem and the multi-biomass supply chain. Renewable and Sustainable Energy Review 13:887-894.