1,761 research outputs found
Winners and Losers: Spatial variations in labour productivity in England and Wales
This paper presents an investigation into the static and dynamic spatial pattern of aggregate labour productivity across England and Wales at the district and unit authority level. This analysis is complemented by plant-level regressions to identify the contribution of industrial sectors to each NUTS1 region’s average labour productivity. Using data for 1998 and 2005, our exploratory data analysis illustrates that there are stable spatial patterns in levels of labour productivity and that labour productivity change does not appear to be spatially dependent, at least not at this spatial scale. Furthermore the economic importance of different sectors to different regions evolves over time, which makes regional industrial policy formation problematic.Labour productivity; districts and local authorities; sectors; spatial autocorrelation
A unit commitment study of the application of energy storage toward the integration of renewable generation
To examine the potential benefits of energy storage in the electric grid, a
generalized unit commitment model of thermal generating units and energy storage
facilities is developed. Three different storage scenarios were tested—two without
limits to total storage assignment and one with a constrained maximum storage
portfolio. Given a generation fleet based on the City of Austin’s renewable energy
deployment plans, results from the unlimited energy storage deployment scenarios
studied show that if capital costs are ignored, large quantities of seasonal storage
are preferred. This operational approach enables storage of plentiful wind
generation during winter months that can then be dispatched during high cost peak
periods in the summer. These two scenarios yielded 94 million in
yearly operational cost savings but would cost hundreds of billions to implement.
Conversely, yearly cost reductions of $40 million can be achieved with one
compressed air energy storage facility and a small set of electrochemical storage
devices totaling 13GWh of capacity. Similarly sized storage fleets with capital
costs, service lifetimes, and financing consistent with these operational cost savings
can yield significant operational benefit by avoiding dispatch of expensive peaking
generators and improving utilization of renewable generation throughout the year.
Further study using a modified unit commitment model can help to clarify optimal
storage portfolios, reveal appropriate market participation approaches, and
determine the optimal siting of storage within the grid.Mechanical Engineerin
Can switching fuels save water? A life cycle quantification of freshwater consumption for Texas coal-and natural gas-fired electricity
Thermal electricity generation is a major consumer of freshwater for cooling, fuel extraction and air
emissions controls, but the life cycle water impacts of different fossil fuel cycles are not well understood.
Much of the existing literature relies on decades-old estimates for water intensity, particularly regarding
water consumed for fuel extraction. This work uses contemporary data from specific resource basins and
power plants in Texas to evaluate water intensity at three major stages of coal and natural gas fuel cycles:
fuel extraction, power plant cooling and power plant emissions controls. In particular, the water intensity
of fuel extraction is quantified for Texas lignite, conventional natural gas and 11 unconventional natural
gas basins in Texas, including major second-order impacts associated with multi-stage hydraulic
fracturing. Despite the rise of this water-intensive natural gas extraction method, natural gas extraction
appears to consume less freshwater than coal per unit of energy extracted in Texas because of the high
water intensity of Texas lignite extraction. This work uses new resource basin and power plant level
water intensity data to estimate the potential effects of coal to natural gas fuel switching in Texas’ power
sector, a shift under consideration due to potential environmental benefits and very low natural gas
prices. Replacing Texas’ coal-fired power plants with natural gas combined cycle plants (NGCCs) would
reduce annual freshwater consumption in the state by an estimated 53 billion gallons per year, or 60% of
Texas coal power’s water footprint, largely due to the higher efficiency of NGCCs.Mechanical Engineerin
Microeconomic foundations of geographical variations in labour productivity
This paper initially presents an exploratory spatial data analysis which indicates the presence of small-scale geographical variations in levels and standard deviations of labour productivity across England and Wales in 2005. We identify the presence of spatial autocorrelation for both measures. This finding motivates a subsequent review and extension of theories which suggest the possible presence of small-scale geographical patterns of labour productivity.Labour productivity; standard deviation; districts and local authorities; geographical autocorrelation
Evaluation of power generation operations in response to changes in surface water reservoir storage
We used a customized, river basin-based model of surface water rights to evaluate the response
of power plants to drought via simulated changes in reservoir storage. Our methodology
models surface water rights in 11 river basins in Texas using five cases: (1) storage decrease of
existing capacity of 10%, (2) storage decrease of 50%, (3) complete elimination of storage,
(4) storage increase of 10% (all at existing locations), and (5) construction of new reservoirs
(at new locations) with a total increase in baseline reservoir capacity for power plant cooling
of 9%. Using the Brazos River basin as a sample, we evaluated power generation operations in
terms of reliability, resiliency, and vulnerability. As simulated water storage decreases,
reliability generally decreases and resiliency and vulnerability remain relatively constant. All
three metrics remain relatively constant with increasing reservoir storage, with the exception
of one power plant. As reservoir storage changes at power plants, other water users in the
basin are also affected. In general, decreasing water storage is beneficial to other water users
in the basin, and increasing storage is detrimental for many other users. Our analysis reveals
basin-wide and individual power plant-level impacts of changing reservoir storage,
demonstrating a methodology for evaluation of the sustainability and feasibility of
constructing new reservoir storage as a water and energy management approach.Mechanical Engineerin
Accommodating migration to promote adaptation to climate change
This paper explains how climate change may increase future migration, and which risks are associated with such migration. It also examines how some of this migration may enhance the capacity of communities to adapt to climate change. Climate change is likely to result in some increase above baseline rates of migration in the next 40 years. Most of this migration will occur within developing countries. There is little reason to think that such migration will increase the risk of violent conflict. Not all movements in response to climate change will have negative outcomes for the people that move, or the places they come from and go to. Migration, a proven development strategy, can increase the capacity of communities to adapt to climate change. The fewer choices people have about moving, however, the less likely it is that the outcomes of that movement will be positive. Involuntary resettlement should be a last resort. Many of the most dire risks arising from climate-motivated migration can be avoided through careful policy. Policy responses to minimize the risks associated with migration in response to climate change, and to maximize migration’s contribution to adaptive capacity include: ensuring that migrants have the same rights and opportunities as host communities; reducing the costs of moving money and people between areas of origin and destination; facilitating mutual understanding among migrants and host communities; clarifying property rights where they are contested; ensuring that efforts to assist migrants include host communities; and strengthening regional and international emergency response systems.Population Policies,Climate Change Mitigation and Green House Gases,Health Monitoring&Evaluation,Climate Change Economics,Voluntary and Involuntary Resettlement
Why forums? An empirical analysis into the facilitating factors of carding forums
Over the last decade, the nature of cybercrime has transformed from naive vandalism to profit-driven, leading to the emergence of a global underground economy. A noticeable trend which has surfaced in this economy is the repeated use of forums to operate online stolen data markets. Using interaction data from three prominent carding forums: Shadowcrew, Cardersmarket and Darkmarket, this study sets out to understand why forums are repeatedly chosen to operate online stolen data markets despite numerous successful infiltrations by law enforcement in the past. Drawing on theories from criminology, social psychology, economics and network science, this study has identified four fundamental socio-economic mechanisms offered by carding forums: (1) formal control and coordination; (2) social networking; (3) identity uncertainty mitigation; (4) quality uncertainty mitigation. Together, they give rise to a sophisticated underground market regulatory system that facilitates underground trading over the Internet and thus drives the expansion of the underground economy
Job Loss and Effects on Firms and Workers
This paper serves as an introduction and (incomplete) survey of the wide-ranging literature on job loss. We begin with a discussion of job stability in the US and the commitment between firms and workers, and how this has changed in recent years. We then focus on the short and long-term consequences to workers (i.e. wages, health outcomes) following a layoff, and the effect which mass layoffs have on future firm performance. The changing nature of these relationships over the past several decades is a central theme of this paper. We review the common data sources used to examine these questions, and identify many influential papers on each topic. Additionally, we discuss alternative policies to the typical mass layoff, such as worksharing
Comparing post-combustion CO2 capture operation at retrofitted coal-fired power plants in the Texas and Great Britain electric grids
Stuart Cohen is with UT Austin, Hannah Chalmers is with University of Edinburgh, Michael Webber is with UT Austin, and Carey King is with UT AustinThis work analyses the carbon dioxide (CO2) capture system operation within the Electric Reliability
Council of Texas (ERCOT) and Great Britain (GB) electric grids using a previously developed
first-order hourly electricity dispatch and pricing model. The grids are compared in their 2006
configuration with the addition of coal-based CO2 capture retrofits and emissions penalties from 0 to
100 US dollars per metric ton of CO2 (USD/tCO2). CO2 capture flexibility is investigated by
comparing inflexible CO2 capture systems to flexible ones that can choose between full- and zero-load
CO2 capture depending on which operating mode has lower costs or higher profits. Comparing these
two grids is interesting because they have similar installed capacity and peak demand, and both are
isolated electricity systems with competitive wholesale electricity markets. However, differences in
capacity mix, demand patterns, and fuel markets produce diverging behaviours of CO2 capture at
coal-fired power plants. Coal-fired facilities are primarily base load in ERCOT for a large range of CO2
prices but are comparably later in the dispatch order in GB and consequently often supply intermediate
load. As a result, the ability to capture CO2 is more important for ensuring dispatch of coal-fired
facilities in GB than in ERCOT when CO2 prices are high. In GB, higher overall coal prices mean that
CO2 prices must be slightly higher than in ERCOT before the emissions savings of CO2 capture offset
capture energy costs. However, once CO2 capture is economical, operating CO2 capture on half the
coal fleet in each grid achieves greater emissions reductions in GB because the total coal-based
capacity is 6 GW greater than in ERCOT. The market characteristics studied suggest greater
opportunity for flexible CO2 capture to improve operating profits in ERCOT, but profit improvements
can be offset by a flexibility cost penalty.Mechanical Engineerin
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Development of a Rooftop Collaborative Experimental Space through Experiential Learning Projects
The Solar, Water, Energy, and Thermal Laboratory
(SWEAT Lab) is a rooftop experimental space at the
University of Texas at Austin built by graduate and
undergraduate students in the Cockrell School of
Engineering. The project was funded by the Texas State
Energy Conservation Office and the University’s Green
Fee Grant, a competitive grant program funded by UT
Austin tuition fees to support sustainability-related projects
and initiatives on campus. The SWEAT Lab is an on-going
experiential learning facility that enables engineering
education by deploying energy and water-related projects.
To date, the lab contains a full weather station tracking
weather data, a rainwater harvesting system and rooftop
garden.
This project presented many opportunities for students to
learn first hand about unique engineering challenges. The
lab is located on the roof of the 10 story Engineering
Teaching Center (ETC) building, so students had to design
and build systems with constraints such as weight
limitations and wind resistance. Students also gained
experience working with building facilities and
management for structural additions, power, and internet
connection for instruments.
With the Bird’s eye view of UT Austin campus, this unique
laboratory offers a new perspective and dimension to
applied student research projects at UT Austin.Cockrell School of Engineerin
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