Edward Benjamin
Senior Managing Director, eCycleElectric Consultants
Chairman, Light Electric Vehicle Association
Intuitively, we would all agree that a human powered bike is more environmentally friendly than an electric bike.
And just asking this question tends to upset the human powered bike people.
But it may not be true.
Here are the elements of carbon production / environmental pollution to consider:
For ebikes:
Taking raw materials such as steel, paint, aluminum, lithium, etc, and turning these into the components of a finished electric bike. There is a substantial carbon cost to this process.
Generation of electricity to recharge the battery.
Disposal of the spent battery, and later the spent vehicle.
Disposal of worn out tires, other parts.
Ebike energy is usually provided by electrical network, which is usually powered by some large generation plant.
An important thing to realize about this energy source is that the mains current provided by the electrical grid is the result of a very efficient process, on a very large scale. And there are many alternatives brought on line all the time that reduce the carbon production of electrical grids. Wind, solar, nuclear, hydro are all part of the mix.
In many places, the amount of carbon that is allowed by regulation is quite modest compared to the amount of work the energy produced can accomplish.
Intuitively, we think that energy used to propel a muscle powered bike is carbon neutral.
However, the production of the food that fuels the rider is not. Agriculture uses lots of fuel and chemicals. Transportation of food uses more fuel. Refrigeration and distribution uses fuel and energy.
And if the rider eats a lot of meat (especially beef) such food carries a very high carbon cost. (As well as high water usage, land usage, etc.)
Conclusion:
Tomi Engel from Deutsche Gesellschaft fur Sonnenenergie e.V. published a study in 2008 that concluded that electric bikes as a form of transportation create less of a carbon cost than human powered bikes…..
Unless….the rider ate only potatoes.
Since energy sources are more and more often renewables, it is likely that even a potato only diet now has more carbon production than an ebike.
And yes…the study ignores the benefit to the rider of exercise resulting in better fitness. This was a study about energy use and carbon production.
Anyone who wants a copy of the study presentation can contact me at ed@eCycleElectric.com