Why Electric Bikes Are So Much Greener Than E-Cars

Last week we published a story on why we want an electric bike subsidy. This got people talking and there were a few comments on Facebook that we could not answer in just a few short words.

Published: Friday 22 June 2018

Electric bikes are much greener than e-cars

Last week we published a story on why we at E-Bikes Direct want an electric bike subsidy to get more people on their bikes and out of their cars. This got people talking and there were a few comments on Facebook (see here) that we could not answer in just a few short words.

Congestion

One of the comments in the Facebook thread asked, “Why make a comparison that makes no sense? Why not compare it to, say a 50cc moped / scooter? That would be a valid comparison.”

It isn’t. We are arguing that firstly, e-bikes tackle congestion and secondly they are more carbon efficient than petrol / diesel and even e-cars.

An e-car will take the same space in the traffic as a petrol / diesel car. Tightly packed at the lights, you could fit around four bikes in the same space as a car. Even in a typical car sharing system this allows twice as many people per car space in the traffic. That will arguably take 2-3 cars off the road with that density of cyclists.

According to the RAC, there are around 31.2 million cars on UK roads. 200,000 are electric, or around 0.6% of the UK car fleet. Most of the cars you ‘take out’ by people riding e-bikes will be petrol or diesel.

Imagining that bike use gets to the crazy levels you see in China, and only the elite in their Maybachs drove to work then you would see traffic density fall by 300%, and transport pollution the same. That’s impossible but you can see the immediate impact. Sweden’s e-bike grant has had 42,000 applicants this year, and this may well hit as many as 84,000 before the grant runs out of money.

Let’s just assume that 42,000 ebikes are commuting machines. Based on each bike taking out 3 car spaces in the traffic, across the UK that would take out 126,000 car spaces in the traffic. Adding to the existing number of commuting bikes, you will see congestion related pollution plummet and some cities rush hour traffic go from a walking pace crawl to an efficient flow.

Well to wheel

The most important comment on the Facebook post we had was this:

“Nice idea. Just how much are carbon emissions reduced when compared to a bicycle?”

Let’s now look at a thorny issue called ‘well to wheel’, where e-cars are compared in carbon emissions to petrol / diesel cars.

The measure has been established as the formula comparing carbon emissions from the moment the crude oil / coal comes out of the ground until it is turned into energy. It is a complicated measure that would need a large amount of time to research but briefly let’s look at how such a comparison is done:

• Energy is emitted in the hydrocarbons being taken out of the ground
• They are then transported to be refined
• Refining puts more carbon in the air.
• The clean hydrocarbon fuel is then either transported to a power plant or sent to a petrol station at a cost of more carbon.
• Parallel to this you have the energy and emissions that is put into the building of the vehicle.
• The hydrocarbons are burned to produce the energy, releasing more carbon.
• The energy is used in locomotion.
• You also have ‘zero carbon’ renewable energy in the mix, currently around 12% in the UK. The more renewable energy the cleaner the e-car is.

Well to wheel measurements have been done comparing e-cars to fossil fuel cars, but not fossil fuel cars to e-bikes. We will look at a myth busting blog in Clean Technica that argues that e-cars are more carbon hungry than fossil fuel cars and then show you roughly how more fuel efficient electric bikes are than e-cars.

Clean Technica - are fossil fuel cars less carbon hungry than battery cars?

The blog reported on a detailed well to wheel assessment based on e-car use in the US. The Clean Technica  blog stated, “We found that battery electric cars generate half the emissions of the average comparable gasoline car, even when pollution from battery manufacturing is accounted for.” Before dirty energy friendly Mr Trump became President, the US and UK electricity grid energy mix was broadly the same.

We could copy the argument made by Clean Technica showing you how emissions are higher during battery production but lower at every stage, but we will trust you to read the blog yourself. We need to move onto electric bikes.

Electric bikes consume 1/440th the energy of an e-car

A 2018 Nissan Leaf has a 110 kilowatt motor. Electric bikes in Europe are only allowed a 250 watt motor. The Leaf’s motor is 440 times more powerful than an electric bike motor.

Let’s look at that another way - based on the motor alone and not the components in the e-car, that would be 1/880th of the carbon emitted per mile of a petrol car, assuming that an e-bike had as complex a battery system as well as all the components that an electric car has. It doesn’t - even a top of the range Haibike sDuro Trekking 9.0  has a fraction of the parts involved. Could the e-bike consume 1/2000th the carbon emissions of a fossil fuel car? That is not improbable.

Yes, this has been a back of an envelope estimate!

Regarding congestion and well to wheel we have not been concise here. We have only shown you how e-bikes can take a lot less space on the road and that they consume a fraction of the energy from manufacturing to the daily commute. Those two points can be hacked into solid figures, and we are confident that those figures will show that e-bikes are a country mile more efficient in getting people to work than e-cars. Electric bikes are the better transport mode - full stop!