KDF Search Results

For analyzing sustainability of algal biofuels, we identify 16 environmental indicators that fall into six categories: soil quality, water quality and quantity, air quality, greenhouse gas emissions, biodiversity, and productivity. Indicators are selected to be practical, widely applicable, predictable in response, anticipatory of future changes, independent of scale, and responsive to management.

Biofuels are promoted in the United States through aggressive legislation, as one part of an overall strategy to lessen dependence on imported energy as well as to reduce the emissions of greenhouse gases (Office of the Biomass Program and Energy Efficiency and Renewable Energy, 2008). For example, the Energy Independence and Security Act of 2007 (EISA) mandates 36 billion gallons of renewable liquid transportation fuel in the U.S. marketplace by the year 2022 (U.S. Government, 2007).

This review on research on life cycle carbon accounting examines the complexities in accounting for carbon emissions given the many different ways that wood is used. Recent objectives to increase the use of renewable fuels have raised policy questions, with respect to the sustainability of managing our forests as well as the impacts of how best to use wood from our forests. There has been general support for the benefits of sustainably managing forests for carbon mitigation as expressed by the Intergovernmental Panel on Climate Change in 2007.

Adding bioenergy to the U.S. energy portfolio requires long‐term profitability for bioenergy producers and
long‐term protection of affected ecosystems. In this study, we present steps along the path toward evaluating both sides of
the sustainability equation (production and environmental) for switchgrass (Panicum virgatum) using the Soil and Water
Assessment Tool (SWAT). We modeled production of switchgrass and river flow using SWAT for current landscapes at a

A working paper review of current approaches to accounting for indirect land-use changes in green house gas balances of biofuels. This report reviews the current effort made worldwide to address this issue. A
description of land-use concepts is first provided (Section 2) followed by a classification of
ILUC sources (Section 3). Then, a discussion on the implications of including ILUC
emissions in the GHG balance of biofuel pathways (Section 4) and a review of methodologies
being developed to quantify indirect land-use change (Section 5) are presented. Section 6

Land-use changes are frequently indicated to be one of the main human-induced factors influencing the groundwater system. For land-use change, groundwater research has mainly focused on the change in water quality thereby neglecting changes in quantity. The objective of this paper is to assess the impact of land-use changes, from 2000 until 2020, on the hydrological balance and in particular on groundwater quantity, as results from a case study in the Kleine Nete basin, Belgium.

Agricultural activities have dramatically altered our planet?s land surface. To understand the extent and spatial distribution of these changes, we have developed a new global data set of croplands and pastures circa 2000 by combining agricultural inventory data and satellite-derived land cover data. The agricultural inventory data, with much greater spatial detail than previously available, is used to train a land cover classification data set obtained by merging two different satellite-derived products (Boston University?s MODIS-derived land cover product and the GLC2000 data set).

National interests in greater energy independence, concurrent with favorable market forces, have driven increased production of corn-based ethanol in the United States and research into the next generation of biofuels. The trend is changing the national agricultural landscape and has raised concerns about potential impacts on the nation?s water resources. This report examines some of the key issues and identifies opportunities for shaping policies that help to protect water resources.

Growing concern about climate change and energy security has led to increasing interest in developing renewable, domestic energy sources for meeting electricity, heating and fuel needs in the United States. Illinois has significant potential to produce bioenergy crops, including corn, soybeans, miscanthus (Miscanthus giganteus), and switchgrass (Panicum virgatum). However, land requirements for bioenergy crops place them in competition with more traditional agricultural uses, in particular food production.

Fertilizers used to increase the yield of crops used for food or bio-based products can migrate through the environment and potentially cause adverse environmental impacts. Nitrogen fertilizers have a complex biogeochemical cycle. Through their transformations and partitioning among environmental compartments, they can contribute to eutrophication of surface waters at local and regional scales, groundwater degradation, acid rain, and climate change.

Land-use change models are important tools for integrated environmental management. Through scenario analysis they can help to identify near-future critical locations in the face of environmental change. A dynamic, spatially explicit, land-use change model is presented for the regional scale: CLUE-S. The model is specifically developed for the analysis of land use in small regions (e.g., a watershed or province) at a fine spatial resolution.

A series of life cycle assessments (LCA) have been conducted on biomass, coal, and natural gas systems in order to quantify the environmental benefits and drawbacks of each. The power generation options that were studied are: (1) a biomass-fired integrated gasification combined cycle (IGCC) system using a biomass energy crop, (2) a direct-fired biomass power plant using biomass residue, (3) a pulverized coal (PC) boiler representing an average U.S. coal-fired power plant, (4) a system cofiring biomass residue with coal, and (5) a natural gas combined cycle power plant.

An analysis was performed at NREL to examine the global warming potential and energy balance of power generation from fossil and biomass systems including CO2 sequestration. To get the true environmental picture, a life cycle approach, which takes into account upstream process steps, was applied. Each system maintained the same constant generating capacity and any lost capacity due to CO2 sequestration was accounted for by adding power generation from a natural gas combined-cycle system. This paper discusses the systems examined and gives the net energy and GWP for each system.

The generation of electricity, and the consumption of energy in general, often result in adverse effects on the environment. Coal-fired power plants generate over half of the electricity used in the U.S., and therefore play a significant role in any discussion of energy and the environment. By cofiring biomass, currently-operating coal plants have an opportunity to reduce the impact they have, but to what degree, and with what trade-offs? A life cycle assessment (LCA) has been conducted on a coal-fired power system that cofires wood residue.

It is technically feasible to capture CO2 from the flue gas of a coal-fired power plant and various researchers are working to understand the fate of sequestered CO2 and its long term environmental effects. Sequestering CO2 significantly reduces the CO2 emissions from the power plant itself, but this is not the total picture.

This report discusses the development of greenhouse gas (GHG) emissions estimates for the production of Fischer-Tropsch (FT) derived fuels (in particular, FT diesel), makes comparisons of these estimates to reported literature values for petroleum-derived diesel, and outlines strategies for substantially reducing these emissions.

Coal has the largest share of utility power generation in the U.S., accounting for approximately 56% of all utility-produced electricity (U.S. DOE, 1998). Therefore, understanding the environmental implications of producing electricity from coal is an important component of any plan to reduce total emissions and resource consumption.

It has become widely accepted that biomass power offers opportunities for reduced environmental impacts compared to fossil fuel-based systems. Intuitively obvious are the facts that per kilowatt-hour of energy produced, biomass systems will emit less CO2 and consume less non-renewable energy.

A life cycle assessment (LCA) of different coal-fired boiler systems was performed at NREL in collaboration with the Federal Energy Technology Center. Three designs were examined to evaluate the environmental aspects of current and future coal systems.

Biodiesel is a renewable diesel fuel substitute. It can be made from a variety of natural oils and fats. Biodiesel is made by chemically combining any natural oil or fat with an alcohol such as methanol or ethanol. Methanol has been the most commonly used alcohol in the commercial production of biodiesel. In Europe, biodiesel is widely available in both its neat form (100% biodiesel, also know as B100) and in blends with petroleum diesel. European biodiesel is made predominantly from rapeseed oil (a cousin of canola oil).