研究表明，电动自行车可以显著减少温室气体排放

研究表明，电动自行车可以显著减少温室气体排放

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."

我们喜欢电动自行车有很多原因(真正合法的电动自行车，而不是被西蒙·考威尔抛弃的那种)，主要的一个原因是它们的碳足迹比汽车低。这似乎是显而易见的，但没有什么是不能通过研究来证实和量化的。这就是Michael McQueen, John Macarthur和Christopher Cherry在《电动自行车的潜力:评估区域电动自行车对温室气体排放的影响》一书中所做的。

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."

研究人员研究了俄勒冈州波特兰市的电动自行车的影响，并指出除了减少二氧化碳排放外，电动自行车还有其他好处，比如“对许多用户来说，它是有益的和有趣的，对那些能力和行动能力有限的用户来说是自由的，甚至可以让家庭无车。”他们还证实，人们骑电动自行车要比骑普通自行车走得更远，“这意味着电动自行车可以成倍地增加传统自行车带来的好处。”

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."

研究人员使用了之前一项关于电动自行车使用情况的研究数据，该研究调查了电动自行车使用者的使用情况，以及他们的交通方式从驾驶或运输方式改变后的情况。然后他们用非常简单的数学方法计算了每种交通工具的个人旅行里程，每一种交通形式乘以每一种交通形式的排放，输入“当地人口信息、按模式计算的出行产生、按模式计算的行程长度、汽车占用率、汽车燃油经济性、按个人里程计算的交通燃油经济性，以及电动自行车的排放率”。他们以俄勒冈州的波特兰作为案例研究对象，因为“当地交通数据的可用性和该市自行车网络的广博性，有利于电动自行车的使用。”

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.

这项研究考虑了当地电力供应的排放情况，但实际上，电动自行车所使用的能源太小了，几乎无关紧要;即使是污染最严重的燃煤电厂，平均排放量也只有12.568克/英里(也许是我见过的最愚蠢的单位，用公制或英制单位，随便选一个)，而波特兰是4.9克/英里;一辆汽车是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.

在这种情况下，我们发现使用PMT共享15%的电动自行车模式可以减少12%的交通二氧化碳排放，每辆电动自行车每年平均减少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."

虽然交通排放减少12%已经很不错了，但我们还需要更多。我们需要比15%更大的模式份额才能真正发挥作用。电动自行车让这变得更容易;作者指出，“与传统自行车相比，电动自行车可以减少残疾和行动不便的骑手、年长的骑手和女性骑手的障碍。”

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."

他们还建议采取其他措施，包括补贴、收费和停车设施，并指出“降低机动车辆的速度和数量，建立独立的自行车道或“高速公路”，也有助于增加电动自行车。”

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

15%的目标还远远不够;想象一下两倍于它会有什么不同。