Link to the website with documentation and download instructions for the PNNL Global Change Assessment Model (GCAM), a community model or long-term, global energy, agriculture, land use, and emissions. BioEnergy production, transformation, and use is an integral part of GCAM modeling and scenarios.
Landscape implications of bioenergy feedstock choices are significant and depend on land-use practices and their environmental impacts. Although land-use changes and carbon emissions associated with bioenergy feedstock production are dynamic and complicated, lignocellulosic feedstocks may offer opportunities that enhance sustainability when compared to other transportation fuel alternatives. For bioenergy sustainability, major drivers and concerns revolve around energy security, food production, land productivity, soil carbon and erosion, greenhouse gas emissions, biodiversity, air quality, and water quantity and quality. The many implications of bioenergy feedstock choices require several indicators at multiple scales to provide a more complete accounting of effects. Ultimately, the long-term sustainability of bioenergy feedstock resources (as well as food supplies) throughout the world depends on land-use practices and landscape dynamics. Land-management decisions often invoke trade-offs among potential environmental effects and social and economic factors as well as future opportunities for resource use. The hypothesis being addressed in this paper is that sustainability of bioenergy feedstock production can be achieved via appropriately designed crop residue and perennial lignocellulosic systems. We find that decision makers need scientific advancements and adequate data that both provide quantitative and qualitative measures of the effects of bioenergy feedstock choices at different spatial and temporal scales and allow fair comparisons among available options for renewable liquid fuels.
This report is a collective effort of the Scientific Committee on Problems of the Environment (SCOPE), including contributions from 137 researchers of 82 institutions in 24 countries. It concludes that land availability is not a limiting factor to bioenergy production and that bioenergy can contribute to sustainable energy supplies even with increasing food demands, preservation of forests, protected lands, and rising urbanization.
The report estimates that at least 500 million hectare of land are available for bioenergy production without compromising needs such as food production. This area of land is easily greater than the projected 50–200 million hectare that are needed to provide 10%–20% of primary energy supply in 2050. If pasture intensification and the use of marginal or degraded land is considered, the total available land rises to 900 million hectares.
The 21 chapters of this report document how the use of land for bioenergy is inextricably linked to food security, environmental quality, and social development. Potentially positive or negative consequences to bioenergy production essentially depend on how these linkages are managed.
The Scientific Committee on Problems of the Environment (SCOPE) is an international nongovernmental organization founded in 1969 that connects experts and institutions around the world across disciplines and across sectors. It is recognized for its authoritative, independent, and influential scientific analyses and assessments of emerging environmental issues that are caused by or impact humans and the environment. SCOPE collaborates with inter-governmental agencies such as the United Nations Educational, Scientific and Cultural Organization, the United Nations Environment Programme, and with other partners in the development of its scientific program and outreach activities.
Land-use change (LUC) is a contentious policy issue because of its uncertain, yet potentially substantial, impact on bioenergy climate change benefits. Currently, the share of global GHG emissions from biofuels-induced LUC is small compared to that from LUC associated with food and feed production and other human-induced causes. However, increasing demand for biofuels derived from feedstocks grown on agricultural land could increase this contribution. No consensus has emerged on how to appropriately isolate and quantify LUC impacts of bioenergy from those of other LUC drivers. We reviewed the literature and illustrate some strategies to minimize bioenergy-related LUC, including ways to increase land’s total productivity and the design and implementation of effective land use policies. The best strategies to reduce LUC risk will vary geographically, requiring a balancing of the advantages and limitations of potential options within the local context together with other goals (social, environmental, economic, energy security, and diversification).
Increasing demand for crop-based biofuels, in addition to other human drivers of land use, induces direct and indirect land use changes (LUC). Our system dynamics tool is intended to complement existing LUC modeling approaches and to improve the understanding of global LUC drivers and dynamics by allowing examination of global LUC under diverse scenarios and varying model assumptions. We report on a small subset of such analyses. This model provides insights into the drivers and dynamic interactions of LUC (e.g., dietary choices and biofuel policy) and is not intended to assert improvement in numerical results relative to other works.
Demand for food commodities are mostly met in high food and high crop-based biofuel demand scenarios, but cropland must expand substantially. Meeting roughly 25% of global transportation fuel demand by 2050 with biofuels requires >2 times the land used to meet food demands under a presumed 40% increase in per capita food demand. In comparison, the high food demand scenario requires greater pastureland for meat production, leading to larger overall expansion into forest and grassland. Our results indicate that, in all scenarios, there is a potential for supply shortfalls, and associated upward pressure on prices, of food commodities requiring higher land use intensity (e.g., beef) which biofuels could exacerbate.