Transportation remains the fastest growing source of global carbon dioxide emissions, but the majority of trips people take—to school, to work, and for errands—are less than 10 miles, perfect for E-bike travel.As of now E-bikes, make up about 7% of urban passenger travel distance worldwide, Let’s say city dwellers opted to use bicycles or electric bikes for just 10% of their urban trips instead of using motor vehicles. Greenhouse gas emissions coming from motor vehicles in big cities worldwide would drop by 11%, saving society $24 trillion in infrastructure and other costs by 2050. However, according to one study there is potential that number could increase to 22% by 2050. This would reduce emissions 47% and save $128 trillion compared to business-as-usual. But E-Bikes need energy to charge, and your body needs energy to operate it. How do all those factors add up? Ideally, E-bikes are charged using low-carbon energy sources like residential solar panels. Even if powered by a dirtier electricity grid — Like coal-burning power plants in China — E-bikes are still the most energy-efficient form of motorized transport, consuming the electricity equivalent of about 1,000 miles per gallon of gasoline.”E-bikes are green, even when they rely on dirty technologies,” Christopher Cherry, a professor from the University of Tennessee who has been researching transportation in China since 2005 said in an interview with Forbes, “There is no other mainstream motorized mode that matches that efficiency,” Cherry said. “Even when 100% charged by coal power plants, they are quite clean compared to every alternative.” When you factor in the fat you burn cycling, one a study by the European Cyclists Federation (ECF) found that “even taking into account the additional dietary intake of a cyclist compared with that of a motorised transport user” emissions from cycling are more than 10 times lower than those stemming from the passenger car. When the complete life cycle of each mode is calculated, here’s how they stack up (results in grams of CO2 per passenger per kilometer traveled):Bicycle: 21 gElectric-assist bicycle: 22 g (e-bikes scored well due to larger range of standard bicycle and therefore greater chance to replace passenger car trips)Passenger car: 271 g (based on short trips similar to those a bicycle could make)Bus: 101 g Investing in a Lithium-ion battery reduces the impact on the environment further. Even with the wide range of prices available for E-bikes, the purchase price and operating costs are lower than owning a car. One of the primary differences in price for E-Bikes depends on the battery. Lead acid battery versions are inexpensive, while more expensive lithium-ion batteries are lighter, more reliable, and much better for the environment. Still, as battery technology advances and competition in the E-bike manufacturing space continues, the price of both E-bikes and batteries are coming down swiftly. More people willing to make E-bikes part of their commute also creates the potential for more green spaces in cities — 20 bikes can potentially fit in one car space — and the reduction of noise produced by motor vehicles.