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Cities increasingly face challenging regulatory requirements for their aging sewer systems. Population density and can contribute to changes in impervious cover that limit infiltration, expedite the rate of water drainage, and overwhelm the conveyance system. This work presents a method for applying high-spatial resolution population-based scenarios to pre-existing stormwater models. We explore the impact of two long-term population growth scenarios for the Pittsburgh region. We find that an extreme 79% growth in population results in 24% increase in impervious area and an 11% increase in total overflows. In contrast, a moderate 15% rise in population yields an 8% increase in impervious area and a corresponding 5% increase in overflows. As the relationship between population growth, impervious area, and total sewer overflow is non-linear, it is of critical importance to understand neighborhood-level changes. Our work fills a critical scalar gap for adding robustness analysis to these projections.

Using data on a mid-sized community college in northeast Ohio as a case study, we examine patterns of enrollment in petroleum technology credential programs and labor market returns to those credentials. The enrollment analysis yields mixed results. Strong industry conditions represented by an increase in oil prices is associated with a decline in program enrollment; however, higher wages for petroleum workers is associated with increased program enrollment. Earning analyses were unambiguous: Obtaining a certificate or an associate’s degree was associated with outsized quarterly earnings returns of $2,900 and $5,500, respectively. This study suggests that partnerships that align subbaccalaureate postsecondary education to the needs of local labor markets may result in occupational credentials with substantially larger returns than those observed in the literature.

Pipelines are responsible for the transportation of a significant portion of the U.S. energy supply. Unfortunately, pipeline failures are common and the consequences can be catastrophic. Drawing on data from the Pipeline and Hazardous Materials Safety Administration (PHMSA) that covers approximately 40,000 incidents from 1968 to 2009, this paper explores the trends, causes and consequences of natural gas and hazardous liquid pipeline accidents. The analysis indicates that fatalities and injuries from pipeline accidents are generally decreasing over time, while property damage and, in some cases, the numbers of incidents are increasing over time. In five of the ten cases considered in this paper, the damage from pipeline accidents – in terms of injuries, fatalities and volume of product spilled – are well characterized by a power-law distribution, indicating that catastrophic pipeline accidents are more likely than would be predicted by more common “thin-tailed” distributions. The results also indicate that relatively few accidents account for a large share of total property damage, while smaller, single-fatality and single-injury incidents account for a large share of total fatalities and injuries (43% versus 32%, respectively).

This second of five annual reports focuses on employment and wages in energy and advanced manufacturing–related industries and on science, technology, engineering, and mathematics (STEM) education in the Ohio, Pennsylvania, and West Virginia region. These reports will capture trends about which localities might have greater demand for educating or employing local talent in STEM careers and guide investments and collaborative work.

When wind or solar energy displace conventional generation, the reduction in emissions varies dramatically across the United States. Although the Southwest has the greatest solar resource, a solar panel in New Jersey displaces significantly more sulfur dioxide, nitrogen oxides, and particulate matter than a panel in Arizona, resulting in 15 times more health and environmental benefits. A wind turbine in West Virginia displaces twice as much carbon dioxide as the same turbine in California. Depending on location, we estimate that the combined health, environmental, and climate benefits from wind or solar range from $10/MWh to $100/MWh, and the sites with the highest energy output do not yield the greatest social benefits in many cases. We estimate that the social benefits from existing wind farms are roughly 60% higher than the cost of the Production Tax Credit, an important federal subsidy for wind energy. However, that same investment could achieve greater health, environmental, and climate benefits if it were differentiated by region.

This brief summarizes the outcomes of two summers of voluntary academic programming (2013 and 2014) on 3,192 low-income urban students accepted into the programs who had completed third grade before the first summer.

This first of five annual reports focuses on employment and wages in energy and advanced manufacturing–related industries and on science, technology, engineering, and mathematics (STEM) education indicators in the Appalachia Partnership Initiative (API) region. These reports will inform the regional stakeholder community about localities with greater demand for STEM careers and guide API investments and collaborative work.

There is growing interest in reducing emissions from electricity generation in the United States (U.S.). Renewable energy, energy efficiency, and energy conservation are all commonly suggested solutions. Both supply- and demand-side interventions will displace energy-and emissions-from conventional generators. Marginal emissions factors (MEFs) give a consistent metric for assessing the avoided emissions resulting from such interventions. This paper presents the first systematic calculation of MEFs for the U.S. electricity system. Using regressions of hourly generation and emissions data from 2006 through 2011, we estimate regional MEFs for CO(2), NO(x), and SO(2), as well as the share of marginal generation from coal-, gas-, and oil-fired generators. Trends in MEFs with respect to system load, time of day, and month are explored. We compare marginal and average emissions factors (AEFs), finding that AEFs may grossly misestimate the avoided emissions resulting from an intervention. We find significant regional differences in the emissions benefits of avoiding one megawatt-hour of electricity: compared to the West, an equivalent energy efficiency measure in the Midwest is expected to avoid roughly 70% more CO(2), 12 times more SO(2), and 3 times more NO(x) emissions.

Although the benefits of distributed cogeneration are widely cited, adoption has been slow in the United States. Adoption could be encouraged by making cogeneration more economically attractive, either by increasing the expected returns or decreasing the risks of such investments. We evaluate the expected returns from demand response, capacity markets, regulation markets, accelerated depreciation, pricing CO 2 emissions, and net metering. We find that (1) there is an incentive to overcommit in the capacity market due to lenient non-response penalties, (2) there is significant revenue potential in the regulation market, though demand-side resources are yet to participate, (3) a price on CO 2 emissions will make cogeneration more attractive relative to conventional, utility-supplied energy, and (4) accelerated depreciation is an easy and effective mechanism for improving the economics of cogeneration. We go on to argue that uncertainty in fuel and electricity prices present a significant risk to cogeneration projects, and we evaluate the effectiveness of feed-in tariffs at mitigating these risks. We find that guaranteeing a fixed electricity payment is not effective. A two-part feed-in tariff, with an annual capacity payment and an energy payment that adjusts with fuel costs, can eliminate energy-price risks.