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In order to determine what characteristics influence participation in this program I gathered data from multiple sources. I use a panel dataset of household water consumption that spans 12 years of approximately 300,000 homes. I merged this dataset with home structural characteristics, geographical, and demographic context. I then use these characteristics in a linear probability model, with school enrollment zone fixed effects to determine their influence on a household’s probability of participation. School zones are used to control for unobserved characteristics, such as demographics, which are not at a household level. I then utilize these school zone fixed effects in a 2nd stage regression to decompose these elements and analyze their effect on participation.
I find that a household’s water costs, as reflected in the marginal price faced in the summer and the differential between summer and winter water bills, as well as yard size are primary factors that influence participation. I also show that changes in rebate value and water rates can affect different types of households. There is also evidence to support that neighborhood characteristics affect a household’s likelihood of participating.



After a brief introduction to Functional Magnetic Resonance Imaging (fMRI), this paper presents some common misunderstandings and problems that are frequently overlooked in the application of the technology. Then, in three progressively more involved examples, the paper demonstrates (a) how use of fMRI in pre-surgical mapping shows promise, (b) how its use in lie detection seems questionable, and (c) how employing it in defining personhood is useless and pointless. Finally, in making a case for emergentism, the paper concludes that fMRI cannot really tell us as much about ourselves as we had hoped. Since we are more than our brains, even if fMRI were perfect, it is not enough.

In recent years, concerns have grown over the risks posed by climate change on the U.S. electricity grid. The availability of water resources is integral to the production of electric power, and droughts are expected to become more frequent, severe, and longer-lasting over the course of the twenty-first century. The American Southwest, in particular, is expected to experience large deficits in streamflow. Studies on the Colorado River anticipate streamflow declines of 20-45% by 2050. Other climactic shifts—such as higher water and air temperatures—may also adversely affect power generation. As extreme weather becomes more common, better methods are needed to assess the impact of climate change on power generation. This study uses a physically-based modeling system to assess the vulnerability of power infrastructure in the Southwestern United States at a policy-relevant scale.
Thermoelectric power—which satisfies a majority of U.S. electricity demand—is vulnerable to drought. Thermoelectric power represents the backbone of the U.S. power sector, accounting for roughly 91% of generation. Thermoelectric power also accounts for roughly 39% of all water withdrawals in the U.S.—roughly equivalent to the amount of water used for agriculture. Water use in power plants is primarily dictated by the needs of the cooling system. During the power generation process, thermoelectric power plants build up waste heat, which must be discharged in order for the generation process to continue. Traditionally, water is used for this purpose, because it is safe, plentiful, and can absorb a large amount of heat. However, when water availability is constrained, power generation may also be adversely affected. Thermoelectric power plants are particularly susceptible to changes in streamflow and water temperature. These vulnerabilities are exacerbated by environmental regulations, which govern both the amount of water withdrawn, and the temperatures of the water discharged. In 2003, extreme drought and heat impaired the generating capacity of more than 30 European nuclear power plants, which were unable to comply with environmental regulations governing discharge temperatures. Similarly, many large base-load thermoelectric facilities in the Southeastern United States were threatened by a prolonged drought in 2007 and 2008. During this period, the Tennessee Valley Authority (TVA) reduced generation at several facilities, and one major facility was shut down entirely. To meet demand, the TVA was forced to purchase electricity from the grid, causing electricity prices to rise.
Although thermoelectric power plants currently produce most of the electric power consumed in the United States, other sources of power are also vulnerable to changes in climate. Renewables are largely dependent on natural resources like rain, wind, and sunlight. As the quantity and distribution of these resources begins to change, renewable generation is also likely to be affected. Hydroelectric dams represent the largest source of renewable energy currently in use throughout the United States. Under drought conditions, when streamflow attenuates and reservoir levels drop, hydroelectric plants are unable to operate at normal capacity. In 2001, severe drought in California and the Pacific Northwest restricted hydroelectric power generation, causing a steep increase in electricity prices. Although blackouts and brownouts were largely avoided, the Northwest Power and Conservation Council estimated a regional economic impact of roughly $2.5 to $6 billion. In addition to hydroelectric power, it has also been theorized that solar energy resources may also be susceptible to predicted increases in surface temperature and atmospheric albedo. One study predicts that solar facilities in the Southwestern U.S. may suffer losses of 2-5%.
The aim of this study is to estimate the extent to which climate change may impact power generation in the Southwestern United States. This analysis will focus on the Western Interconnection, which comprises the states of Washington, Oregon, California, Idaho, Nevada, Utah, Arizona, Colorado, Wyoming, Montana, South Dakota, New Mexico and Texas. First, climactic and hydrologic parameters relevant to power generation are identified for five types of generation technologies. A series of functional relationships are developed such that impacts to power generation can be estimated directly from changes in certain meteorological and hydrological parameters. Next, climate forcings from the CMIP3 multi-model ensemble are used as inputs to a physically-based modeling system (consisting of a hydrological model, an offline routing model, and a one-dimensional stream temperature model). The modeling system is used to estimate changes in climactic and hydrologic parameters relevant to electricity generation for various generation technologies. Climactic and hydrologic parameters are then combined with the functional relationships developed in the first step to estimate impacts to power generation over the twenty-first century.

In an effort to provide drinking water treatment options that are simple to operate, two hybrid resins have been developed that can treat multiple pollutants in a single step. A parent weak base anion exchange resin is embedded with nanoparticles made of either iron hydroxide or titanium dioxide (Fe-WBAX and Ti-WBAX, respectively). These provide targeted treatment for both arsenic and hexavalent chromium, common groundwater pollutants of recent regulatory significance. The project goal is to evaluate the environmentally preferable choice between Fe-WBAX and Ti-WBAX resin for simultaneous treatment of arsenic and hexavalent chromium in drinking water. The secondary goal is to identify where in the product life cycle is the most opportunity to reduce the environmental impact of the use of either product.

The ultimate goal of this LCA is to give Arizona State University specific advice on possible changes in lighting systems that will reduce environmental impacts and support ASU’s sustainability efforts. The aim is to assess the potential for a decrease in specific environmental impacts (CO2 emissions and energy use) and economic impact (cost) from changing to a different type of lighting in a prototypical classroom in Wrigley Hall. The scope of this assessment is to analyze the impacts of T8 lamps lasting 50,000 hours. Thus, a functional unit was defined as 50,000 hours of use, maintaining roughly 825 lumens. To put this in perspective, 50,000 hours is equivalent to 8 hours of use per day, 365 days per year, for approximately 17.1 years.


Results are available here.
The environmental life cycle assessment of electric rail public transit modes requires an assessment of electricity generation mixes. The provision of electricity to a region does not usually adhere to geopolitical boundaries. Electricity is governed based on lowest cost marginal dispatch and reliability principles. Additionally, there are times when a public transit agency may purchase wholesale electricity from a particular service provider. Such is the case with electric rail modes in the San Francisco Bay Area.
An environmental life cycle assessment of San Francisco Bay Area public transit systems was developed by Chester and Horvath (2009) and includes vehicle manufacturing/maintenance, infrastructure construction/operation/maintenance, energy production, and supply chains, in addition to vehicle propulsion. For electric rail modes, vehicle propulsion was based on an average electricity mix for the region. Since 2009, new electricity contract information and renewable electricity goals have been established. As such, updated life cycle results should be produced.
Using recent wholesale electricity mix and renewable electricity goal data from the transit agencies, updated electricity precombustion, generation, transmission, and distribution environmental impacts of vehicle propulsion are estimated. In summary, SFMTA Muni light rail is currently purchasing 100% hydro electricity from the Hetch Hetchy region of California and the Bay Area Rapid Transit (BART) system is purchasing 22% natural gas, 9% coal, 2% nuclear, 66% hydro, and 1% other renewables from the Pacific Northwest . Furthermore, the BART system has set a goal of 20% renewables by 2016. Using the GREET1 2012 electricity pathway, a life cycle assessment of wholesale and renewable electricity generation for these systems is calculated.
Chester and Horvath (2009)

The US-Canadian electricity grid is a network of providers and users that operate almost completely independently of one another. In August of 2003, First Energy’s (FE) Harding-Chamberlain transmission line near Akron, Ohio went offline starting a series of cascading failures that eventually led to 8 US states and 1 Canadian province totaling nearly 50 million people without power. The failure of transmission lines are common occurrences relating to the inability to exactly predict the electricity demand at any time (as will be discussed later in this document). The inability to properly monitor and react across multiple organizations to the downed line was the true failure that led to the blackout. This outage not only left homes and businesses without power but paralyzed critical public services such as transportation networks and hospitals. The estimated cost of the outage is between 4 and 6 billion US dollars.