Should I use an electric bike?

Electric bikes can be very clean in terms of GHG emissions. They use electricity which can be zero carbon; making the batteries are the main source of emissions in most cases. In comparison, using cars, tyre wear is a major source of microplastic pollution - the tyres wear out as do the lines of paint on the road which flake off but bicycles are much lighter so there is less wear both on tyres and paint. In particular an electric bike can enable carbon savings compared to alternative transport options. A small group from Transition Cambridge were talking about this yesterday.

One of our number was recently recovered from knee problems which prevented them from using a conventional push bike for long or hilly journeys. Using an electric bike allowed them to make longer journeys (e.g. 20 miles) without 'range anxiety' due to the dodgy knees. Assuming the journey was necessary, alternative transport modes (such as car or bus) would have had higher GHG emissions due to use of fossil fuels as well as additional microplastic pollution from tyre/road wear [1]  Using the electric bike reduces your climate change impact.

You could save even more emissions by not using the battery power to assist your movement. However, that would mean more food consumption and more range anxiety.

The European Cycling Federation has reported a comprehensive life cycle analysis calculation comparing different transport modes: pushbike, ebike and walking in terms of emissions per km travelled [2]. The ebike comes out best by some margin. The differences are dominated by emissions from food. Walking requires the most food, then the pushbike, then the ebike. The food emissions can be reduced if the human consumes a carbohydrate rich diet - or it can be hugely increased if the dietary energy is mainly meat. The chart below shows the GHG emissions they calculate. They have used 383 g CO2e per/Wh for electricity and 1.4 gCO2e/Wh for food: typical for Europe. The emissions for UK electricity are less 177 g CO2e/Wh [3]: Overall the DESNZ/DEFRA emissions factors for EVs [3] are typically about 40 g/CO2e/km so between cycling and walking estimates.

Data from [2]

[1] Bike-to-Work Day: Keep the Car in Park to Reduce Microplastic Pollution (oceandiagnostics.com) 

[2] How green is cycling? Riding, walking, ebikes and driving ranked (bikeradar)

[3] UK Government GHG Conversion Factors for Company Reporting