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Abstract: This paper analyzes the welfare effects of slot controls on major US airports. We consider the fundamental tradeoff between benefits from queuing delay reduction and costs due to simultaneous schedule delay increase to passengers while imposing slot limits at airports. A set of quantitative models and simulation procedures are developed to explore the possible airline scheduling responses through reallocating and trimming flights. We find that, of the 35 major US airports, a more widespread use of slot controls would improve travelers’ welfare. The results from our analyses suggest that slot caps at the four airports that currently have slot controls (Washington Reagan, Newark, New York LaGuardia, New York John F. Kennedy) are set too high. Further slot reduction by removing some of the flights at these airports could generate additional benefits to passengers. Slot controls can potentially reduce two thirds of the total system delays caused by congestion. A number of implementation and design issues related to the use of slot controls are also discussed in the paper. [Copyright &y& Elsevier]

• Aggregation and cooperation among peers will expand beyond prosumers in microgrids. • Growth in IoT and metering infrastructure is empowering end-use consumers. • Methodology allows aggregated consumers to schedule load and share energy. • Application demonstrates a significant cost reduction while assuring fairness. • Offers a novel cost-sharing strategy guided by cost minimization and Nash bargaining. End-use consumers (peers) are being empowered to aggregate for direct demand-side participation through load scheduling and energy sharing. This is the result of the growth of Internet of Things (IoT) enabled loads, availability of advanced metering infrastructure, and the move towards real-time (RT) pricing of electricity. Peer-to-peer (P2P) cooperation has received significant interest in recent years, though the focus of this growing body of research is on modeling prosumer behavior in microgrids. Hence, there is a need for new methodologies to examine empowerment of all end-use consumers (not limited to prosumers) to form aggregations and develop fair rules of cooperation to reduce cost. This paper offers an optimization based methodology to address the above need for power systems. It minimizes the total cost and considers fairness using a Nash bargaining approach. Since cost and fairness are often in conflict, trade-off strategies are also presented. The model to asses fairness is nonlinear. Hence, it is transformed into a second order cone program (SOCP) and solved using GUROBI software version 7.5.2. The methodology is implemented on a sample 5-bus network, built using price and demand data from one of the load zones of Pennsylvania, New Jersey, and Maryland (PJM) power network in the United States. It is shown that two aggregations of peers participating in the sample network can reduce their total cost by 14.17% and 22.7%, while maintaining fairness. Concluding remarks highlight some of the limitations of the methodology. [ABSTRACT FROM AUTHOR]

• Substitution of 2nd generation for 1st generation biofuel is investigated. • An optimization model for the 2nd generation biofuel supply chain is proposed. • Both economic and environmental performance measures are examined. • 2nd generation biofuel is more cost effective than 1st generation biofuel. • Considering stover handling or not leads to different environmental performances. Multiple generations of biofuel manufacturing technologies have been proposed and developed, among which first generation technology is the most mature. It typically utilizes corn grain as feedstock in bio-refineries in many countries such as the United States. However, the use of edible matter of crops like corn may lead to a food-versus-fuel competition. To address such an issue, second generation biofuel manufacturing technology using the non-edible matter of crops has been developed. In this paper, the economic viability and environmental sustainability are analyzed and quantified, when restructuring the biofuel supply chain from employing first generation manufacturing technology to the one utilizing second generation technology considering the existing supply chain infrastructure. Two supply chain restructuring strategies, i.e., distributed and centralized preprocessing deployment, are modeled for implementing biomass preprocessing for second generation biofuel manufacturing. Bi-objective optimization formulations for the corn stover-sourced biofuel (a typical second generation biofuel) supply chain considering both economic and environmental aspects are proposed under both strategies. Different decision variables such as the locations selected for constructing preprocessing centers and the corresponding corn stover handling capacities of such centers, as well as the material flows between farms, preprocessing centers, and bio-refinery plants are identified. A case study based on the state of Missouri in the United States is implemented to illustrate the effectiveness of the proposed model and analyze the performance of different strategies. The results of the case study show that when corn stover is used as feedstock in bio-refineries, the unit cost of bioethanol production can be reduced, while the unit emission is increased compared to the corn-sourced supply chain under both supply chain restructuring strategies. Specifically, in Missouri where the daily stover handling amount per bio-refinery plant is relatively low and the stover collection radius is relatively small, the centralized strategy outperforms the distributed one with a higher cost reduction and a smaller increase in emissions. It reduces the unit cost by 27.39%, while increasing the unit emission by 24.42%, compared to the corn-sourced supply chain. [ABSTRACT FROM AUTHOR]

Highlights • We analyze the economic value of a U.S windfarm using long-term LCOE information. • Long-term LCOE of wind energy is obtained from two decades of history. • Monte Carlo and Risk-Neutral valuation is used to valuate a reference windfarm. • Managerial flexibilities and generation cost uncertainty make windfarms more valuable. • Real Option accounts for the flexibility of decision-making with stochastic costs. Abstract Renewable energies are a natural replacement for conventional or fossil fuel energy generation. One of these sources, wind energy, has exhibited significant cost reductions during the last decades. Even though this historical cost reduction trend is well known in the industry and in the academia, information on this cost trend and volatility has been scarcely incorporated in previous works, thus a natural concern arises when assessing their influence on the economic valuation of wind farms. Moreover, wind projects are modular in size and have a short time-to-market, providing a valuable managerial flexibility to defer investment under non-attractive market conditions, such as high development cost scenarios. Traditional evaluation tools often consider those scenarios, wrongly assuming that wind-developers would move forward with the project under such conditions. Accordingly, this paper analyzes the effect of incorporating both generation cost history and investment flexibility in the valuation of wind farms in the United States using Real Options methodology. Taking two decades of cost data and a reference wind farm, this "uncertainty-flexibility" effect is incorporated and valued, finding that the value of the wind project is 14.2% larger than the one neglecting such effect – where cost stochasticity and managerial flexibility are ignored. Therefore, traditional tools for project valuation, such as discounted cash flow and scenario analysis can no longer solely be used, as they do not properly account for the cost reduction trend, uncertainty, and managerial flexibility that a wind farm could face. [ABSTRACT FROM AUTHOR]

Graphical abstract Highlights • Technology cost and utility rate structure are key drivers of economic viability of solar and storage systems. • Solar-plus-storage systems are more often economical under time of use and demand charge rates. • Savings from storage-only projects come mainly from demand charge reductions; solar combined with storage also provides energy charge savings. • Savings from solar with storage is largely independent of building load variability, likely due to the energy cost reductions from the solar. Abstract This paper explores the economics of solar-plus-storage projects for commercial-scale, behind-the-meter applications. It provides insight into the near-term and future solar-plus-storage market opportunities across the U.S. We explore the impacts of location, building load profile, technology cost, utility rate structure, and policies on solar-plus-storage economic viability, and identify which factors are most significant to project economics. While savings from storage-only projects are largely derived from demand charge reductions, solar combined with storage also provides significant energy charge savings. A common assumption is that load profiles with peaks are likely candidates for savings from storage, due to the opportunity for demand charge reduction. Our results indicate that potential for savings from combining solar with storage is independent of building load variability, likely due to the energy cost reductions from the solar. Systems are more often economical under time of use and demand charge rates, particularly when demand charges are >$10 per kilowatt. Where systems were found to be economical, expected lifetime savings averaged between 7%–10%, with savings of 30% in numerous cases. Near term markets exist for solar-plus-storage in locations such as California and New York. As technology prices drop, the number of building types that can benefit increase, and additional markets appear in Colorado, New Mexico, and Alaska. All data from the study and interactive modeling results are available at: https://openei.org/wiki/Solar+Storage. [ABSTRACT FROM AUTHOR]

Abstract: NASA’s Discovery, Explorer, and Mars Scout mission lines have demonstrated over the past 15 years that, with careful planning, flexible management techniques, and a commitment to cost control, small space science missions can be built and launched at a fraction of the price of strategic missions. Many credit management techniques such as co-location, early contracting for long-lead items, and a resistance to scope creep for this, but it is also important to examine what may be the most significant variable in small mission implementation: the roles and the relationship of the principal investigator, responsible to NASA for the success of the mission, and the project manager, responsible for delivering the mission to NASA. This paper reports on a series of 55 oral histories with principal investigators, project managers, co-investigators, system engineers, and senior management from nearly every competitively selected Discovery mission launched to date that discuss the definition and evolution of these roles and share revealing insights from the key players themselves. The paper will show that there are as many ways to define the principal investigator/project manager relationship as there are missions, and that the subtleties in the relationship often provide new management tools not practical in larger missions. [ABSTRACT FROM AUTHOR]

Abstract: Optimization of combined cooling, heating, and power (CCHP) systems operation commonly focuses only on energy cost. Different algorithms have been developed to attain optimal utilization of CCHP units by minimizing the energy cost in CCHP systems operation. However, other outcomes resulting from CCHP operation such as primary energy consumption and emission of pollutants should also be considered during CCHP systems evaluation as one would expect these outcomes can be subject to regulation. This paper presents an optimization of the operation of CCHP systems for different climate conditions based on operational cost, primary energy consumption (PEC), and carbon dioxide emissions (CDE) using an optimal energy dispatch algorithm. The results for the selected cities demonstrate that in general there is not a common trend among the three optimization modes presented in this paper since optimizing one parameter may reduce or increase the other two parameters. The only cities that show reduction of PEC while also reducing the CDE are Columbus, MS; Minneapolis, MN; and Miami, FL. For these cities the operational cost always increases when compared to the reference case consisting of using a vapor/compression cycle for cooling and natural gas for heating. On the other hand, for San Francisco and Boston, CCHP systems increase the CDE. In general, if CCHP systems increase the cost of operation, as long as energy savings and reduction of emissions are guaranteed, the implementation of these systems should be considered. [Copyright &y& Elsevier]

Increasing “patient engagement” has become a priority for health care organizations and policy-makers seeking to reduce cost and improve the quality of care. While concepts of patient engagement have proliferated rapidly across health care settings, little is known about how health care providers make use of these concepts in clinical practice. This paper uses 20 months of ethnographic and interview research carried out from 2015 to 2016 to explore how health care providers working at two public, urban, safety-net hospitals in the United States define, discuss, and assess patient engagement. We investigate how health care providers describe engagement for high cost patients—the “super-utilizers” of the health care system—who often face complex challenges related to socioeconomic marginalization including poverty, housing insecurity, exposure to violence and trauma, cognitive and mental health issues, and substance use. The health care providers in our study faced institutional pressure to assess patient engagement and to direct care towards engaged patients. However, providers considered such assessments to be highly challenging and oftentimes inaccurate, particularly because they understood low patient engagement to be the result of difficult socioeconomic conditions. Providers tried to navigate the demand to assess patient engagement in care by looking for explicit positive and negative indicators of engagement, while also being sensitive to more subtle and intuitive signs of engagement for marginalized patients. [ABSTRACT FROM AUTHOR]

Context: Tobacco use is a leading cause of preventable death in the U.S. and around the world. Increasing tobacco price through higher taxes is an effective intervention both to reduce tobacco use in the population and generate government revenues. The goal of this paper is to review evidence on the economic impact of tobacco price increases through taxation with a focus on the likely healthcare cost savings and improvements in employee productivity.Evidence Acquisition: The search covered studies published in English from January 2000 to July 2012 and included evaluations of national, state, and local policies to increase the price of any type of tobacco product by raising taxes in high-income countries. Economic review methods developed for The Guide to Community Preventive Services were used to screen and abstract included studies. Economic impact estimates were standardized to summarize the available evidence. Analyses were conducted in 2012.Evidence Synthesis: The review included eight modeling studies, with seven providing estimates of the impact on healthcare costs and three providing estimates of the value of productivity gains. Only one study provided an estimate of intervention costs. The economic merit of tobacco product price increases through taxation was determined from the overall body of evidence on per capita annual cost savings from a conservative 20% price increase.Conclusions: The evidence indicates that interventions that raise the unit price of tobacco products through taxes generate substantial healthcare cost savings and can generate additional gains from improved productivity in the workplace. [ABSTRACT FROM AUTHOR]

Abstract: Consumer perception could play an important role in the adoption of renewable energy technologies. This study aims to explore the role of consumer acceptance and model its effect on residential photovoltaic (PV) adoption. A survey was conducted to understand consumer perceptions of the technology (perception variables), such as perceived cost, perceived maintenance requirement, and environmental concern. To further investigate the adoption potential of residential PV, this paper develops a fuzzy logic inference model to relate consumer perception variables (inputs to the model) to their purchasing probability (output from the model). This model is tested in a case study of residential PV adoption using data from a survey of homeowners in Arizona, United States. The quantitative results of the model demonstrate the role of each perception variable in the consumer acceptance of PV. Public has tended to emphasize on the role of cost reduction in promoting the adoption of residential PV. The results of this study show that other issues such as maintenance requirement and environmental concern are also important. [Copyright &y& Elsevier]

Abstract: In the distribution of international logistics, the choice of the ways of transportation is one of the key factors to reduce the costs of distribution. In view of the countermeasures for the outsourcing and self-run business of the distribution transportation, the author of present paper aims at establishing analytical models, providing solutions which are confirmed by a case study from the investigation conducted in the United States of America, solving the high-cost question that plagues the network of international distribution over a long time, and providing a kind of decisionmaking tools for Chinese products to squeeze into the international market and establish the distribution networks. [Copyright &y& Elsevier]

Abstract: This paper examines the evolution of domestic origin-destination air traffic and fares at the top 200 airports in the US between 1990 and 2008, with a focus on the impacts of low-cost carrier entry and growth. By 2008, 95 of the airports had an aggregate low-cost carrier market share of domestic traffic greater than 20%, up from 27 airports in 1990. Their entry or substantial growth at US airports has had significant impacts on lowering average fares and stimulating passenger volumes. This market stimulation effect has, however, diminished in recent years, as the difference in average fares between carrier types has narrowed and as the number of additional US domestic origin-destination markets able to support their entry has dwindled. [Copyright &y& Elsevier]

Abstract: This paper is the first in the literature to examine the determinants of US credit card penalty fees. Many critics of credit card fees – including a number of US Senators – have argued that credit card penalty fees reflect banks’ market share. Using a unique data set we find that fees are increasing in customer risk which supports the position of defenders of penalty fees, such as banks. However, our finding that fees are increasing in a bank''s market share is consistent with the concerns expressed by politicians and regulators. We also find card penalty fees are direct substitutes for card interest rates. [Copyright &y& Elsevier]

Abstract: Contracted service comprises a significant proportion of total operating expenses in the provision of fixed-route bus transit service in the US. Despite its importance, the literature on the economic effects of transit service contracting has been limited to only a few studies since the mid-1990s, and is inconclusive due to problems with the nature and methodology of the past studies. This paper examines how the cost efficiency of providing fixed-route bus transit service varies by the degree of contracting. I make several improvements to previous studies and conduct a regression analysis that: (1) addresses the endogeneity problem between the contracting decision and cost efficiency, (2) differentiates between agencies that contract out only a portion of service from those that contract out all service, (3) takes into account the moderating effects of several factors on the effect of contracting on cost efficiency, and (4) uses a relatively larger set of cross-sectional time-series data constructed from the National Transit Database from 1992 to 2000. The analysis results show that the combined effects of contracting lower operating costs by $4.09 and $2.89 per vehicle hour for partial and full-contracting agencies, respectively, in the average case. These average cost savings translate into 7.8% and 5.5%, using the average operating cost per vehicle hour of $53.06. However, this improvement is not universal, because the effects of contracting on cost efficiency vary by factors such as peak-to-base ratio, agency size, the wage gap between bus operators in the public and private sectors, and agency type. [Copyright &y& Elsevier]

Abstract: This paper evaluates the feasibility of a platinum leasing program for future fuel-cell vehicles (FCVs) in the United States. By internalizing the residual value of platinum in the vehicle''s upfront cost, a platinum lease may offer cost savings to the consumer. Several leasing scenarios were evaluated to estimate potential cash savings. The study concludes that under ideal conditions, the upfront price of platinum could be reduced by 40% compared to a no-lease scenario. However, even small increases in the lease rate greatly reduce these savings. The benefits depend on the extent to which lending risks are minimized, and on the vehicle''s platinum loading. These benefits will be greatest during initial stages of market penetration, when the technology is less proven and platinum loadings are highest. To ensure low lease rates, governmental support is likely necessary, both to minimize risk exposure and borrowing costs, and to optimize platinum recovery. [Copyright &y& Elsevier]

Abstract: We examine the impacts of the EU–US Open Skies agreement on the environment on emissions from the aviation sector. We use the Hamburg Tourism Model of domestic and international tourist numbers and flows, to estimate these impacts. The Open Aviation Area will result in increased competition between carriers and falls in the cost of transatlantic flights. This will not only have implications for the size and structure of the industry but also for climate policy. The paper assesses what effects the expected increases in passenger numbers will have on CO2 emissions and tests whether this increase in travel will result in a corresponding rise in emissions. Simulations show that passenger numbers arriving from the US to the EU will increase by between 1% and 14% depending on the magnitude of the price reductions because of substitution between destinations, the percentage increase in global emissions is much smaller (max. 1%) than the increase in cross-Atlantic traffic. [Copyright &y& Elsevier]

Abstract: In 2008 the ‘joint open aviation area’ between the US and EU will become reality. It is expected that competition will increase. The reaction of the airlines depends on the possibility to make profits in ‘new’ markets (markets that can now be entered). This, in turn, depends on network characteristics. In this paper we find that full liberalization of international markets by means of a bilateral agreement results in higher welfare than the formation of an alliance. Carriers, however, will also in fully deregulated aviation markets most likely opt for an alliance. This is a result of a built-in competitive effect of hub–spoke networks. Only in markets where the reservation price is very high (e.g. to London Heathrow), hub–spoke airlines may enter a competitive game. Low-cost airlines, which do not operate extensive hub–spoke networks, may find it profitable to enter new markets. [Copyright &y& Elsevier]

The United States biofuel mandate might be the largest operating program to reduce greenhouse gas (GHG) emissions. This paper uses regulatory information about abatement and compliance cost estimates to measure the greenhouse gas abatement cost curve of the mandate. Historical compliance costs per unit of biofuel appear readily available, yet findings here show that using these data along with observed biofuel quantities biases biofuel mandate abatement cost estimates upward. Unbiased estimation requires that related biofuel mandate costs and emissions are estimated along with associated market effects, including on fuel use, using an economic model. Moreover, this approach relates greenhouse gas abatement to the implications for crop prices and land use, taking account of interactions within the crop sector. Results show that the United States biofuel mandate causes up to 20 million metric tons of carbon dioxide equivalent abatement for compliance costs that are equivalent to carbon prices ranging up to $20 per ton, with a large part coming from reductions in petroleum product use as the mandate encourages substitution to biofuels. Abatement costs are reduced if ethanol is made at new facilities with fewer emissions or if petroleum output expansion causes greater emissions than the historical average. Findings also indicate that GHG abatement via the mandate is initially costly due to the nature of biofuel demand, there can be a trade-off between corn price increase and GHG reduction, and the increase in total area planted to crops in the U.S. is less important than the reallocation of land among crops. Image 1 • Biofuel mandate compliance costs can be used to estimate GHG abatement costs. • Historical mandate compliance data, alone, can miscount costs and abatement. • Economic simulations estimate the U.S. biofuel mandate abatement cost curve. • Mandate GHG abatement costs relate to commodity prices and land use. • Ethanol from new facilities and petroleum from new sources reduce abatement costs. [ABSTRACT FROM AUTHOR]