Nearly all US locomotives are propelled by diesel-electric drives, which emit 35 million tonnes of CO2 and produce air pollution causing about 1,000 premature deaths annually, accounting for approximately US$6.5 billion in annual health damage costs. Improved battery technology plus access to cheap renewable electricity open the possibility of battery-electric rail. Here we show that a 241-km range can be achieved using a single standard boxcar equipped with a 14-MWh battery and inverter, while consuming half the energy consumed by diesel trains. At near-future battery prices, battery-electric trains can achieve parity with diesel-electric trains if environmental costs are included or if rail companies can access wholesale electricity prices and achieve 40% use of fast-charging infrastructure. Accounting for reduced criteria air pollutants and CO2 emissions, switching to battery-electric propulsion would save the US freight rail sector US$94 billion over 20 years.
International maritime shipping—powered by heavy fuel oil—is a major contributor to global CO2, SO2, and NOx emissions. The direct electrification of maritime vessels has been underexplored as a low-emission option despite its considerable efficiency advantage over electrofuels. Past studies on ship electrification have relied on outdated assumptions on battery cost, energy density values and available on-board space. We show that at battery prices of US$100 kWh−1 the electrification of intraregional trade routes of less than 1,500 km is economical, with minimal impact to ship carrying capacity. Including the environmental costs increases the economical range to 5,000 km. If batteries achieve a US$50 kWh−1 price point, the economical range nearly doubles. We describe a pathway for the battery electrification of containerships within this decade that electrifies over 40% of global containership traffic, reduces CO2 emissions by 14% for US-based vessels, and mitigates the health impacts of air pollution on coastal communities.
The role of bicyclists as consumers is explored through an examination of the relationship between travel mode and shopping behavior. As cities develop policies to combat congestion and reduce emissions from the transportation sector, tension often develops when scarce road space must be allocated, particularly in dense urban cores. The challenge is to accommodate all travel modes and ensure that local businesses are not negatively affected by infrastructure changes. Previous studies in the United States and abroad focused primarily on consumable goods, not retail expenditures. These studies demonstrated that bicyclists made more frequent purchases than their car-driving and transit-riding counterparts and tended to shop at small businesses close to home, whereas motorists spent more money on single occasions. The objective of this study was to examine differences in shopping behavior between bicyclists and motorists–-two groups that are in perpetual competition for parking space and other infrastructure accommodations–-in downtown Davis, California. Two cross-sectional online surveys in 2009 and 2010 that asked questions about recent shopping in downtown Davis provide the data set. Respondents who biked on their most recent trips downtown spent, on average, slightly more on their purchases each trip than their car-driving counterparts. Bicyclists also made more frequent shopping trips and thus spent more money at downtown establishments than customers traveling by car.
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