電動車長期的使用費，比汽油和卡車便宜，不會製造污染也不加劇氣候變遷，但美國人反應並不熱烈。
美國總統歐巴馬在2011年國情咨文演說中，發下2015年讓1百萬台電動車上路的豪語。當時產業分析師和業界人士皆認為不可能──現在看來的確如此──2010年電動車上市至今，美國車商只賣出25萬輛電動車。
價格高 充電站數少 電動車銷路不如預期
根據研究公司Autodata Corp的網站motorintelligence.com調查，美國車商2013年賣出超過1千3百萬輛汽油客車、小貨卡、休旅車和小巴，2014年則超過1千4百萬輛。
美國能源部認為這也和電動車的售價高昂有關。電動車價格從15,000到70,000美元不等，越高檔的電動車，價格越讓人卻步。
康乃爾大學學者童朗和李善軍認為，美國電動車普及速度慢其實是雞生蛋、蛋生雞的問題。雞是美國城市和高速公路的電動車充電站數量有限；蛋則是電動車業者因為電動車數量不多，不願意增加充電站。
童朗和李善軍主張，充電不便是電動車發展的主要瓶頸。他們發現，充電站多的城市，電動車數量較多，而城市的充電站數量只要每1百萬人增加10%，就能讓該城市的電動車市佔率增加10.8%。
他們也認為市中心、購物中心停車場、集合公寓和商業區需要更多充電站。分析2011年至2013年353個都會區的電動車季銷量後，童朗認為，「電動車市佔率和充電站的普及程度之間有高度相關。」
市場要普及 充電技術需革新
童朗和李善軍的研究計畫：「電動運輸的工程和經濟解決方案」，目標之一是發展出讓電動車可以透過既有電網大規模充電、而且具有成本效益的技術變革。
目前大部分電動車主用120V家用插座充電整晚。有些人在家安裝240V充電站，讓充電時間減半。第三種方法是買可直流快速充電的電動車。充電速度比交流電快6倍，不過價格在15,000到25,000美元之間。
童朗和李善軍相信，更有效率、能節省電費的充電方式將有助電動車的普及。
他們正在研究車庫太陽能板充電和當地儲能的可能性，以及如何利用電力市場的價格差異幫助電動車普及。同時，他們也在設計高效率、大規模的充電設施，利用智慧能源管理系統，使購物中心和停車場的電動車充電成本最佳化，讓電動車可以直接從電網充電。
President Barack Obama set a goal in his 2011 State of the Union speech – put one million electric vehicles on the road by 2015. But auto analysts and executives doubted that was possible. Turns out the doubters were right. U.S. car dealers have sold just over 250,000 electric vehicles since they were introduced in 2010.
U.S. car dealers sold more than 13 million petrol-powered passenger cars, light pickup trucks, SUVs and vans in 2013 and more than 14 million in 2014, according tomotorintelligence.com, a site provided by Autodata Corp.
The U.S. Department of Energy says the high purchase price of EVs is partly to blame. Electric vehicles range in price from about US$15,000 to more than $70,000. At the upper end of that scale, the purchase price can be prohibitive.
EVs are cheaper to operate than petrol-powered cars and trucks in the long run and they produce no air pollution. Nor to they contribute to climate change. But American drivers have been slow to switch.
Trying to solve the riddle of Americans’ sluggish acceptance of electric vehicles, Lang Tong and Shanjun Li, researchers at Cornell University, frame the issue as a traditional chicken and egg riddle – which came first, the chicken or the egg?
The chicken is the limited number of EV charging stations in U.S. cities and along highways.
Tong and Li contend this poses a major roadblock to greater acceptance because recharging EVs can be inconvenient, if not impossible, in many places.
The egg is that investors are reluctant to build more charging stations, when there are so few electric vehicles on the road.
Through their research Tong and Li found that cities with more charging stations also have more electric cars.
In their analysis, a 10 percent increase in the number of charging stations per million people in a city would result in a 10.8 percent increase in the market share of electric vehicles in that city.
They say more charging stations are needed in parking garages in urban centers, parking lots in shopping malls, apartment complexes and business sites.
After analyzing a data set of quarterly EV sales in 353 metro areas from 2011 to 2013, Tong, a professor of engineering at Cornell, said, “As one might expect, there is a strong dependency between the growth of electric vehicle market share and the available charging options.”
One goal of Tong’s and Li’s INSPIRE project, entitled “An Engineering and Economic Pathway to Electric Vehicle-Based Transportation,” is to consider how to engineer transformative technologies for large scale charging of electric vehicles that can work with existing electric grids in a cost-effective way.
Currently, most EV owners plug in to a standard 120-volt home outlet and charge their batteries overnight. Others pay to install a 240-volt charging station at home, cutting charging times roughly in half.
A third alternative is to purchase an electric vehicle equipped with electrical connections for high, direct-current charging. This can recharge an electric vehicle four to six times faster than an alternating current charger; but the cost typically runs $15,000 to $25,000.
Tong and Li believe more efficient charging options that lower electricity costs would speed up electric vehicle adoption.
They are investigating vehicle charging with solar panels on garages, examining possibilities for local energy storage and studying how to better utilize price differentials in the electricity market.
They also are designing efficient, large-scale charging facilities using an Intelligent Energy Management System that optimizes the cost of vehicle charging at malls or parking garages where many cars could draw energy from the power grid all at once.
※ 全文及圖片詳見：ENS
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In my healing journey and learning to attain the breath awareness, I become aware of the reality that all the creatures of the world are breathing the same breath. Take action, here and now. From my physical being to the every corner of this out of balance's planet.
