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0 pointsTade05y ago0 comments

It's not that clear cut.

Humans are terrible at turning food into energy, and only the most efficient (vegan) foods have a footprint below 1g CO2/kcal.

Your typical vegan on a bicycle has a footprint of 22g CO2/km and that's the best you can get with human-powered transport.

The Ami has a driving footprint of 7g / km in France, a 5.5kWh battery, which has a one-time impact of ~450kg, and seats two.

Long term it's the less impactful opttion really, especially if you take into account that only 2% of the population is vegan.

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yodsanklai5y ago

Not convinced by your conclusion

> Humans are terrible at turning food into energy

Electric bicycles come to mind. They would provide a more direct comparison with the Ami, but being 50 times lighter, I don't see how the Ami could compete.

> a one-time impact of ~450kg

This amounts to 20000km! That's a lot of cycling before the Ami becomes less impactful. Also a battery lifetime is about 5 years.

> Your typical vegan on a bicycle has a footprint of 22g CO2/km

I didn't find this number. "CO2 emissions from the average European diet, which is another 16g per kilometer cycled" [1]

With this number, that would be 30000km of cycling before you even drive one meter with the Ami.

> in France

France electricity production generates very little CO2. In most other countries, the footprint would be much higher making the Ami an even worse option.

It's hard to argue that a 500kg vehicle can be more efficient than a 10kg one (or even 20kg for an electric bicycle).

That being said, it'd be great if Ami could replace more polluting cars for people who dislike cycles

[1] https://ecf.com/news-and-events/news/how-much-co2-does-cycli...

Tade0OP5y ago

Electric bicycles come to mind. They would provide a more direct comparison with the Ami, but being 50 times lighter, I don't see how the Ami could compete.

True, but the level

This amounts to 20000km! That's a lot of cycling before the Ami becomes less impactful. Also a battery lifetime is about 5 years.

A lot of cycling, but not a lot of commuting. Could be done in 4 years.

Also the most significant factor contributing to a battery's degradation is not age, but the number of cycles. Even at the low estimate of 500 cycles(consumer grade battery), it should be good for 35 000km. But since it's likely an automotive battery, one could expect for it to withstand 1000 cycles or 70 000km.

I didn't find this number. "CO2 emissions from the average European diet, which is another 16g per kilometer cycled" [1]

I've read the source and it says:

"at 16 km per hour, a cyclist is burning about 4 kilocalories per kilogram per hour, while the relative metabolic rate of “driving to work” requires no more energy than somebody going about their daily activities: 1,5 kilocalories per kilogram per hour8."

It takes this from * the Compendium of physical activities, 2003* where it's written that:

  0101014.0Bicycling<10 MPH, to work or for pleasure

It's not at. It's less than.

The updated source(2011 Compendium of Physical Activities) says:

  01010 4.0 bicycling, <10 mph, leisure, to work or for pleasure (Taylor Code 115)
  01011 6.8 bicycling, to/from work, self selected pace
  01013 5.8 bicycling, on dirt or farm road, moderate pace
  01015 7.5 bicycling, general
  01018 3.5 bicycling, leisure, 5.5 mph
  01019 5.8 bicycling, leisure, 9.4 mph

They're not actually using the figure for 16km/h - the real figure at this speed is closer to 5.8 calories, which using their parameters yields 27g CO2/km for an average European.

It's hard to argue that a 500kg vehicle can be more efficient than a 10kg one (or even 20kg for an electric bicycle).

Problem is, the 10kg one is powered by a ~70kg biological machine, which isn't very efficient - that's my entire point. Also the 500kg one seats two and can sustain 45km/h for probably 50km or so - not an easy feat for your average cyclist.

But I agree - pedelecs are the most efficient as personal transportation.

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