研究表明，電動自行車可以顯著減少溫室氣體排放

研究表明，電動自行車可以顯著減少溫室氣體排放

There are many reasons we love e-bikes (the real, legal kind, not the thing Simon Cowell got thrown from), the main one being that they have a way lower carbon footprint than cars. This would seem totally obvious, but nothing is so obvious that you can't do a study to confirm and quantify it. That's what Michael McQueen, John Macarthur, and Christopher Cherry did in "The E-Bike Potential: Estimating regional e-bike impacts on greenhouse gas emissions."

我們喜歡電動自行車有很多原因(真正合法的電動自行車，而不是被西蒙·考威爾拋棄的那種)，主要的一個原因是它們的碳足跡比汽車低。這似乎是顯而易見的，但沒有什么是不能通過研究來證實和量化的。這就是Michael McQueen, John Macarthur和Christopher Cherry在《電動自行車的潛力:評估區(qū)域電動自行車對溫室氣體排放的影響》一書中所做的。

The researchers study the impact of e-bikes in Portland, Oregon, and note that there are other benefits besides CO2 emission reductions, such as being "rewarding and fun for many users, is freeing for users with limited ability and mobility, and can even lead to a car-free household." They also confirm that people ride farther on e-bikes than they do on regular bikes, "meaning that e-bikes offer the opportunity to multiply the benefits already available through conventional cycling."

研究人員研究了俄勒岡州波特蘭市的電動自行車的影響，并指出除了減少二氧化碳排放外，電動自行車還有其他好處，比如“對許多用戶來說，它是有益的和有趣的，對那些能力和行動能力有限的用戶來說是自由的，甚至可以讓家庭無車。”他們還證實，人們騎電動自行車要比騎普通自行車走得更遠，“這意味著電動自行車可以成倍地增加傳統(tǒng)自行車帶來的好處。”

A man on an e-bike.

The researchers used data from a previous study of e-bike usage that examined e-bike users and how their transportation changed from driving or transit. Then they did the pretty straightforward mathematics for Personal Miles Traveled (PMT) by each form of transportation times the emissions for each with "local information about population, trip generation by mode, trip length by mode, auto occupancy, auto fuel economy, transit fuel economy by person mile, and e-bike emissions rate as inputs." They used Portland, Oregon as the case study because "of the availability of regional transportation data and the extensiveness of the city’s bike network that lends itself to e-bike uptake."

研究人員使用了之前一項關于電動自行車使用情況的研究數(shù)據(jù)，該研究調查了電動自行車使用者的使用情況，以及他們的交通方式從駕駛或運輸方式改變后的情況。然后他們用非常簡單的數(shù)學方法計算了每種交通工具的個人旅行里程，每一種交通形式乘以每一種交通形式的排放，輸入“當?shù)厝丝谛畔?、按模式計算的出行產生、按模式計算的行程長度、汽車占用率、汽車燃油經濟性、按個人里程計算的交通燃油經濟性，以及電動自行車的排放率”。他們以俄勒岡州的波特蘭作為案例研究對象，因為“當?shù)亟煌〝?shù)據(jù)的可用性和該市自行車網絡的廣博性，有利于電動自行車的使用。”

The study took into account the emissions profile of the local power supply but really, the energy used by an e-bike is so small that it barely matters; even with the dirtiest coal-fired power you get average emissions 12.568 grams/mile (perhaps the silliest unit I have ever seen, go metric or imperial, pick one!) whereas Portland is 4.9 grams/mile; a car is 274.

這項研究考慮了當?shù)仉娏呐欧徘闆r，但實際上，電動自行車所使用的能源太小了，幾乎無關緊要;即使是污染最嚴重的燃煤電廠，平均排放量也只有12.568克/英里(也許是我見過的最愚蠢的單位，用公制或英制單位，隨便選一個)，而波特蘭是4.9克/英里;一輛汽車是274。

In this case, we found that a 15% e-bike mode share by PMT could result in a 12% reduction in transportation CO2 emissions, with an average CO2 savings of 225 kg per e-bike per year.

在這種情況下，我們發(fā)現(xiàn)使用PMT共享15%的電動自行車模式可以減少12%的交通二氧化碳排放，每輛電動自行車每年平均減少225公斤二氧化碳排放。

While a 12% reduction in transport emissions is great, we need more. We need a much greater mode share than 15% to really make a difference. E-bikes make that easier; the authors note that "e-bikes have been shown to reduce barriers for riders with disabilities and mobility issues, older riders, and female riders compared to conventional bicycles."

雖然交通排放減少12%已經很不錯了，但我們還需要更多。我們需要比15%更大的模式份額才能真正發(fā)揮作用。電動自行車讓這變得更容易;作者指出，“與傳統(tǒng)自行車相比，電動自行車可以減少殘疾和行動不便的騎手、年長的騎手和女性騎手的障礙。”

They also suggest other measures to increase ridership, including subsidies, charging, and parking facilities, noting that "Reducing the speeds and volumes of motor vehicles and building separated bike lanes or “superhighways” could also help to increase e-cycling."

他們還建議采取其他措施，包括補貼、收費和停車設施，并指出“降低機動車輛的速度和數(shù)量，建立獨立的自行車道或“高速公路”，也有助于增加電動自行車。”

Fifteen percent is not nearly ambitious enough; imagine the difference if it were double that.

15%的目標還遠遠不夠;想象一下兩倍于它會有什么不同。