KDF Search Results

Sustainable production of algae will depend on understanding trade-offs at the energy-water nexus. Algal biofuels promise to improve the environmental sustainability profile of renewable energy along most dimensions. In this assessment of potential US freshwater production, we assumed sustainable production along the carbon dimension by simulating placement of open ponds away from high-carbon-stock lands (forest, grassland, and wetland) and near sources of waste CO 2 .

Bio-oil derived via fast pyrolysis is being developed as a renewable fuel option for petroleum distillates. The compatibility of neat bio-oil with 18 plastic types was evaluated using neat diesel fuel as the baseline.

Energy market conditions have shifted dramatically since the USA renewable fuel standards (RFS1 in 2005; RFS2 in 2007) were enacted. The USA has transitioned from an increasing dependence on oil imports to abundant domestic oil production. In addition, increases in the use of ethanol, the main biofuel currently produced in the USA, is now limited by the blend wall constraint. Given this, the current study evaluates alternative biofuel deployment scenarios in the USA, accounting for changes in market conditions.

This analysis estimates the cost of selected oil and biomass supply shocks for producers and consumers in the light-duty vehicle fuel market under various supply chain configurations using a mathematical programing model, BioTrans. The supply chain configurations differ by whether they include selected flexibility levers: multi-feedstock biorefineries; advanced biomass logistics; and the ability to adjust ethanol content of low-ethanol fuel blends, from E10 to E15 or E05.

As a promising alternative energy source, biofuel imparts a remarkable role for the sustainability and security in energy sector. Strategies, including policy recommendations have been set to put forward the development and implementation of biofuel by different countries. Recent exploitation of Asian biofuels policy is one step towards destination. These types of activity behind the biofuels would be the catalyst for the productiveness of policy set by individual territory like Malaysia, Thailand, Vietnam, etc.

This paper estimates household preferences for ethanol as a gasoline substitute. I develop a theoretical
model linking the shape of the ethanol demand curve to the distribution of price ratios at which individual
households switch fuels. I estimate the model using data from many retail fueling stations. Demand
is price-sensitive with a mean elasticity of 2.5�3.5. I find that preferences are heterogeneous with many
households willing to pay a premium for ethanol. This reduces the simulated cost of an ethanol content

This report is an update of the original version, which was published in October 2008. This updated report includes results from the complete 16-vehicle fleet (the original report included only the first 13 vehicles tested) as well as corrections to minor errors identified in some of the originally reported data. Conclusions drawn from the complete dataset are nearly identical to those from the
original 13-vehicle fleet but with increased statistical confidence.

We quantify the emergence of biofuel markets and its impact on U.S. and world agriculture for the coming decade using the multi-market, multi-commodity international FAPRI (Food and Agricultural Policy Research Institute) model. The model incorporates the trade-offs between biofuel, feed, and food production and consumption and international feedback effects of the emergence through world commodity prices and trade.

The objective of the research here is to more carefully investigate the claims of localized
impacts on two fronts. The first is the impact a local ethanol plant has on the rate of agricultural
land conversion to other uses (if an ethanol plant increases the value of local agricultural land as
a result of increased commodity prices, one might expect a slower rate of conversion relative to
other communities). Second, we investigate whether the siting of an ethanol plant has had a
negative impact on local residential land values.

This study is a statistical analysis to estimate the significance of factors that influence the volume of E85 sales to the general public in Minnesota from 1997 to 2006.

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

This report identify the issues associated with intermediate ethanol blends with an emphasis on the end-use or
vehicle impacts of increased ethanol levels and compile a current and complete bibliography of key references on intermediate ethanol blends.

The market for E85�a fuel blend of 85 percent ethanol and 15 percent gasoline�is small
but growing rapidly. I use data for E85 sales at fueling stations in Minnesota to estimate
demand for E85 as a function of retail E85 and gasoline prices. I find that demand is
highly sensitive to price changes, with an own-price elasticity as high as -13 and a gasolineprice
elasticity as high as 16 at sample mean price levels. Demand is most sensitive to
price changes when the relative price of E85 is at an intermediate level, at which point

Discussions of alternative fuel and propulsion technologies for transportation often overlook the infrastructure required to make these options practical and cost-effective. We estimate ethanol production facility locations and use a linear optimization model to consider the economic costs of distributing various ethanol fuel blends to all metropolitan areas in the United States. Fuel options include corn-based E5 (5% ethanol, 95% gasoline) to E16 from corn and switchgrass, as short-term substitutes for petroleum-based fuel.

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.

Technology for producing transportation fuel from biomass is moving out of the laboratory and into the marketplace. In the past decade, advances in biotechnology have allowed us to reduce the projected cost of bioethanol by nearly 25%.

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.