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| Fig. 1: An image of an electric bus made and used in Canada. (Source: Wikimedia Commons) |
The Environmental Protection Agency (EPA) reports the U.S. GHG emissions has increased by two percent within the 2012-2013 period. Based on the 1990-2011 U.S. Transportation Sector Greenhouse Gas Emissions Report, transportation vehicles accounted for over a quarter of U.S. GHG emissions in the year 2011. Within that 27 percent, the EPA reports that passenger cars represented 43% and medium and heavyduty trucks were of 22 percent. In addition, adding in light-duty trucks will cause the total percentage of these three sources to account for more than 75% of the transportation End-Use Sector GHG emissions. It is vital to note that the specific transportation greenhouse gases are listed: carbon dioxide, methane, nitrous oxide and hydro-fluorocarbons. Increased emissions from vehicle transportation mileage shows the majority of GHGs in the atmosphere are comprised of 82% carbon dioxide. 27% of the global GHG emissions come from the transportation sector. [1] In 2013, President Barack Obama introduced his Climate Action Plan (CAP). This comprehensive plan is the first of its kind and was developed by the Administration to strategically achieve three overarching goals: cut domestic carbon pollution, prepare the United States for climate change impacts, and lead international efforts to address global climate change. Strategies to meet this goal include reducing GHG emissions from the power sector and promoting energy efficiency and clean energy projects around the country. [2]
Electric school buses have not been implemented yet because of barriers that include high performance, cost measures and battery cost. Of course as you can assume the cost of hybrid school buses is extremely expensive. There has been success in using electric general transportation buses in countries such as Canada, as seen in Fig. 1. Electric vehicles are costly because of the expensive batteries that are used to power them. However, increased purchase of electric cars and batteries potentially offset the high costs and convinced manufacturers to decrease the price due to the high demand and supply. [2] Another huge pro is the energy conservation. The results show that the energy management strategy is effective to control the engine operating in a high-efficiency region as well as to sustain the battery charge state while satisfy the drive ability. The energy consumption is theoretically reduced by 30.3% to that of the conventional bus under transit bus driving cycle. [3] Although the longevity of electric buses have been questioned it is shown that the batteries for the hybrid buses outlast current automotive buses. [2] Only concern is the charging of the buses and if the buses can last as long as their intended bus route without running out of charge.
In regards to energy efficiency we are already seeing a rise in hybrid vehicles. Public transportation is already a huge step in sustainability and energy conservation, by making school buses energy efficient a huge step would be taken towards that goal. It also puts children in clean vehicles. Since rumors of electric buses coming in the near future have been spreading across the the country we should prepare for major enhancement in our energy conservation. Our legislation should continue along this trend and not work to undo all the traction we have gained in this realm. [4]
© Alameen Murphy. The author warrants that the work is the author's own and that Stanford University provided no input other than typesetting and referencing guidelines. The author grants permission to copy, distribute and display this work in unaltered form, with attribution to the author, for noncommercial purposes only. All other rights, including commercial rights, are reserved to the author.
[1] W. R. Morrow et al., "Analysis of Policies to Reduce Oil Consumption and Greenhouse-Gas Emissions From the US Transportation Sector," Energy Policy 38, 1305 (2010).
[2] M. Tubman, "President Obama's Climate Action PlanTwo Years Later," University of Texas at Austin. 27 May 15.
[3] B. Zhou et al., "Real-world Performance of Battery Electric Buses and Their Life-Cycle Benefits With Respect to Energy Consumption and Carbon Dioxide Emissions," Energy 96, 603 (2016).
[4] P. R. Russell, "Trump Reverses Obama Orders on Climate Change," Engineering News-Record, 29 Mar 17.
