Skip to main content
Advanced Search

Filters: Categories: Publication (X)

37,843 results (217ms)   

Filters
Date Range
Extensions
Types
Contacts
Categories
Tag Types
Tag Schemes
View Results as: JSON ATOM CSV
This study proposes a new use of Data Envelopment Analysis (DEA) to measure the operational, environmental and both-unified efficiency measures of US coal-fired power plants. The power plants produce not only desirable outputs (e.g., electricity) but also undesirable outputs (e.g., CO2 and NOx) as a result of their plant operations. A Range-Adjusted Measure (RAM) is used as an original non-radial DEA model. Then, it is reformulated for handling undesirable (bad) outputs. The proposed use of DEA models measures the environmental and unified performance of power plants under two variable alternatives (with and without CO2 emission control) in order to examine both the influence of US Clean Air Act (CAA) on the acid...
Categories: Publication; Types: Citation; Tags: Fact, Silicon, carrier, energy, perspective
This study proposes a new use of Data Envelopment Analysis (DEA) to measure the operational, environmental and both-unified efficiency measures of US coal-fired power plants. The power plants produce not only desirable outputs (e.g., electricity) but also undesirable outputs (e.g., CO2 and NOx) as a result of their plant operations. A Range-Adjusted Measure (RAM) is used as an original non-radial DEA model. Then, it is reformulated for handling undesirable (bad) outputs. The proposed use of DEA models measures the environmental and unified performance of power plants under two variable alternatives (with and without CO2 emission control) in order to examine both the influence of US Clean Air Act (CAA) on the acid...
The Swedish programme for geological disposal of spent nuclear fuel is approaching major milestones in the form of permit applications for an encapsulation plant and a deep geologic repository. This paper presents an overview of the bedrock and surface modelling work that comprises a major part of the on-going site characterization in Sweden and that results in syntheses of the sites, called site descriptions. The site description incorporates descriptive models of the site and its regional setting, including the current state of the geosphere and the biosphere as well as natural processes affecting long-term evolution. The site description is intended to serve the needs of both repository engineering with respect...
This paper distinguishes between Social Impact Assessment (S1A) and the Public Involvement (PI) process and makes a case for PI as an integral part of SlA. PI is seen as activity within the SIA process that provides the social impact assessor with a means to obtain quantitative information regarding social impact assessment variables. In North America during the 1970s SIA began to evolve both separately and as a component of environmental impact assessments. However, the utilization and implementation of SIA procedures have moved forward in an uneven manner among federal agencies. Furthermore, the practice of SIA at the federal or ministerial level has been hindered by the unfortunate equating of SlA with public...
This paper distinguishes between Social Impact Assessment (S1A) and the Public Involvement (PI) process and makes a case for PI as an integral part of SlA. PI is seen as activity within the SIA process that provides the social impact assessor with a means to obtain quantitative information regarding social impact assessment variables. In North America during the 1970s SIA began to evolve both separately and as a component of environmental impact assessments. However, the utilization and implementation of SIA procedures have moved forward in an uneven manner among federal agencies. Furthermore, the practice of SIA at the federal or ministerial level has been hindered by the unfortunate equating of SlA with public...
The United States decided to develop a nuclear power industry in part to justify the continued development of its nuclear weapons program. One result of this decision was the repression of solar energy technology. This paper examines the technical, economical, and political factors which have affected the use of solar energy tech- nology in the United States. I look at how solar and nuclear technologies have devel- oped in the light of competing theories about autonomous and dependent tech- nology. I also outline a strategy for the development of solar photovoltaic technology as an alternative to nuclear power plants.
Very detailed models often hinder the ability to develop a broad, highlevel understanding of system behavior. A system-of-systems perspective combined with a policy analysis approach offers an alternative approach for policy decision-making. This paper specifies the elements of the energy system-of-systems using this new approach and illustrates its use via an example from the Dutch residential sub-sector. The resulting comprehensive problem representation provides meaningful insights into the interdependencies of relevant factors and values among different levels of the system-of-systems covering both the supply and demand side. The paper also shows that despite the high complexity of the energy sector, an energy...
This paper uses the Jobs and Economic Development Impacts (JEDI) model to estimate economic impacts from 1398 MW of wind power development in four counties in west Texas. Project-specific impacts are estimated at the local level (i.e., within a 100-mile radius around the wind farms) and at the state level. The primary economic policy question addressed is how investment in wind energy affects the state and local communities where the wind farms are built. During the four-year construction phase approximately 4100 FTE (full time equivalents) jobs were supported with turbine and supply chain impacts accounting for 58% of all jobs generated. Total lifetime economic activity to the state from the projects equated to...
Categories: Publication; Types: Citation; Tags: Economic impacts, Texas, Wind energy
We have developed a state-scale version of the MARKAL energy optimization model, commonly used to model energy policy at the US national scale and internationally. We apply the model to address state-scale impacts of a renewable electricity standard (RES) and a carbon tax in one southeastern state, Georgia. Biomass is the lowest cost option for large-scale renewable generation in Georgia; we find that electricity can be generated from biomass co-firing at existing coal plants for a marginal cost above baseline of 0.2-2.2 cents/kWh and from dedicated biomass facilities for 3.0-5.5 cents/kWh above baseline. We evaluate the cost and amount of renewable electricity that would be produced in-state and the amount of out-of-state...
We have developed a state-scale version of the MARKAL energy optimization model, commonly used to model energy policy at the US national scale and internationally. We apply the model to address state-scale impacts of a renewable electricity standard (RES) and a carbon tax in one southeastern state, Georgia. Biomass is the lowest cost option for large-scale renewable generation in Georgia; we find that electricity can be generated from biomass co-firing at existing coal plants for a marginal cost above baseline of 0.2-2.2 cents/kWh and from dedicated biomass facilities for 3.0-5.5 cents/kWh above baseline. We evaluate the cost and amount of renewable electricity that would be produced in-state and the amount of out-of-state...
Hydraulic fracturing tests with mud is the most inexpensive method for determining the minor in situ horizontal stress in deep petroleum wells. This paper presents a unified model of pump-in=shut-in and pump-in=flowback tests. The key element of the model is the system stiffness resulting from the stiffness of the fluid volume pressurised, and the stiffness due to the fracture. It is shown that the change in system stiffness at fracture closure is observed in both kinds of tests. The model is used directly in the design and interpretation of the flowback tests, where direct measurement of pressure versus flowback volume, and hence system stiffness is possible. However, the model also predicts the time development...
During the last years, the preservation of the atmospheric environment has played an increasingly important role in society. The Diesel engine can be considered an environmentally friendly engine because of its low consumption and the subsequent carbon dioxide (CO2) emissions reduction. However, in the near future it will face strong restrictive emission standards, which demand that the current nitrogen oxides (NOx) and soot emissions are halved. To comply with these restrictions new combustion concepts are emerging, such as PCCI (premixed charge compression ignition), in which the fuel burns in premixed conditions. Combustion noise is thus deteriorated and consequently end-users could be reluctant to drive vehicles...
The sustainability of the second-generation biofuels requests to confirm that the energy produced from lignocellulosic biomass is significantly greater than the energy consumed in the process. As lignocellulosic biomass does not affect the food supply, sugarcane bagasse was analyzed as a raw material for second-generation biofuels production. Exergy analysis serves as a unified and effective tool to evaluate the global process efficiency. Exergy analysis evaluates the performance of sugarcane bagasse and its sustainability in the bioethanol production process. In this work, four ethanol production topologies using the typical daily amount of residual biomass produced by the sugar industry were compared. The exergy...
Joseph A. Dammel, Jeffrey M. Bielicki, Melisa F. Pollak, and Elizabeth J. Wilson at the University of Minnesota Center for Science, Technology, and Public Policy have published a feature article titled “A Tale of Two Technologies: Hydraulic Fracturing and Geologic Carbon Sequestration” that appears in the online version of the science journal, Environmental Science & Technology [subscription required]. In comparing, contrasting, and analyzing the regulatory landscape governing the use of hydraulic fracturing and geologic carbon sequestration, they conclude that “A shift toward a 21st Century vision of regulation is required. Hydraulic fracturing and geologic sequestration are both technologies that could reduce...
Categories: Publication; Types: Citation; Tags: coal, dynamics, investment, model, system
This paper uses a panel threshold regression (PTR) model to investigate the influence that energy prices have on renewable energy development under different economic growth rate regimes. The empirical data are obtained from each of the OECD member-countries over the period from 1997 to 2006. We show that there is one threshold in the regression relationship, which is 4.13% of a one-period lag in the annual gross domestic product (GDP) growth rate. The consumer price index (CPI), in so far as it relates to variations in energy, is significantly positively correlated with the contribution of renewables to energy supply in the regime with higher-economic growth, but there is no relationship in the regime with lower...
Energy subsidies are widespread around the world but they vary greatly in importance and type of fuel and country. The fossil fuel consumption rate is growing every year and in about 50 years we will have depleted most of our fossil fuel reserves, so it is necessary to find alternative sources of energy before that happens. However, the only solution to this challenge is through investment on energy conservation programmes and renewable energy source. In line with this challenge and confusion on fund appropriate for energy. This paper is aimed at examining the effect of energy subsidy on energy conservation and renewable energy in developing countries. The study intends to quantify and analysis a case study of Trinidad...
This paper analyzes the co-benefits of transport sector electrification in terms of reductions of greenhouse gas and local environmental emissions, improvement in energy security and employment generation during 2015–2050 in the case of Nepal—a developing country with large hydropower potential. A bottom up energy system model of Nepal based on the MARKAL framework was developed to assess the effects of meeting a part of the land transport service demand through electrified mass transport system and electric vehicles. The present study shows that if the share of electricity based transport services is to grow from 10% in 2015 to 35% by 2050, the hydropower generation capacity would have to increase by 495 MW by...
One unconfined compressive strength (UCS) test and four high-pressure triaxial stress tests were conducted on coal cores in order to best emulate the key issues regarding horizontal wellbore stability, coal strength, permeability change, and coal fines generation during the life cycle of a coalbed methane reservoir. The four non-trivial stress paths were: Loading Compression (LC), where the axial stress is increased while the confining stress is held constant; Loading Extension (LE), where the axial stress is held constant while the confining stress is increased; Unloading Compression (ULC), in which the axial stress is held constant while the confining stress is decreased; and Unloading Extension (ULE), during...
This paper is about understanding the role and importance of public responses to offshore wind power. It builds on a framework for understanding social acceptance and opposition to onshore turbines, and reviews the emerging research on offshore wind. While less is known about how people will respond to offshore than onshore wind, there is now an emerging body of research. From this literature, several common factors which influence responses have emerged and are discussed here: the (continued) role of visual impact; place attachment to the local area; lack of tangible benefits; relationships with developers and outsiders; and the role of the planning and decision-making systems. The paper argues that, as with onshore...
The cumulative availability curve shows the quantities of a mineral commodity that can be recovered under current conditions from existing resources at various prices. The future availability of a mineral commodity depends on the shape of its cumulative availability curve (determined by geologic considerations, such as the nature and incidence of the available mineral deposits), the speed at which society moves up the curve (determined by future demand and the extent to which this demand is satisfied by recycling), and shifts in the curve (determined by cost-reducing technological change and other factors). While the shape of the curve for any given mineral commodity may or may not be known, it is knowable since...