I'd love to see some numbers. Given that cheap Chinese gizmos seem to form most of non-food purchases people make, and that they require intercontinental transport, I'd say their footprint is not insignificant.

From the late David JC MacKay's book "sustainable energy: without the hot air" [1] we have the following estimates for per-capita energy consumption in the UK:

all units are kWh/d

  * "defence": 4
  * transporting stuff: 12
  * stuff: 48+
  * food, farming, fertilizer: 15
  * gadgets: 5
  * light: 4
  * heating, cooling: 37
  * jet flights: 30
  * car: 40

the "stuff" category is the energy required to manufacture stuff, including gadgets, houses, cars, roads, washing machines, newspapers, drink containers, computers, etc. note that the energy cost of house construction is estimated at 1 kWh/d per person, while the cost of a new car with a 15 year lifespan is 14 kWh/d, the ignoring energy to run it.

The combined energy cost of stuff and stuff transports is the biggest impact on the list.

although arguably the car is the worst offender if you account for the energy cost of the stuff lifecycle and the energy costs to oeprate it. The estimated energy cost of manufacturing a car with a 15 year lifespan accounts for 14kWh/day of the 48+ kWh/day "stuff" estimate, so if the use of a car was replaced with a magical transport device that required no energy to manufacture or run or dispose of, that would eliminate 14kWh/day from "stuff" and also eliminate the 40 kWh/day car operational energy cost too.

[1] - https://www.withouthotair.com/

Shoo posted some hard figures, but I'd like to add that intercontinental product transport by boat is incredibly efficient.

Efficient in what terms? AFAIK, not in ecological terms, due to the use of low-grade ship bunker fuel: https://www.theguardian.com/environment/2009/apr/09/shipping...

That's something I could never reconcile. On the one hand, I hear that container ships are the most energy-efficient way we have of moving cargo across long distances. On the other hand, we have those issues with crappy fuel.

I wonder:

- What's the total ecological impact of container ships vs. alternative forms of transport using better fuel?

- Would container ships be a Good Thing if we could somehow make them use clean energy? (I just imagined a dream future of fully autonomous, nuclear-powered container ships.)

- If so, why are they still using that shit fuel?

> I just imagined a dream future of fully autonomous, nuclear-powered container ships.

You might want to read about these then:

https://en.wikipedia.org/wiki/Otto_Hahn_(ship)

https://en.wikipedia.org/wiki/Mutsu_(nuclear_ship)

https://en.wikipedia.org/wiki/NS_Savannah

https://en.wikipedia.org/wiki/Sevmorput

It's probably simply a question of the "lawless" open seas permitting absurdly excessive tragedy of the commons-style tradeoffs.

You don't need to go all the way to nuke-carriers; plain old combustion can be much, much cleaner than some ships at negligible (but non-zero) cost - witness similar engines/powerplants on land. But in an extremely competitive market, what sane operator would do that?