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ape4

More feasible than planes to electrify or switch to hydrogen (hydrogenify?)

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Switzerland is one of the few countries that is 100% electrified (decision was made in 1902) and has 5,196 km of rail.

China has 100,000 km electrified which is 66% of their rail while the US has only 2,025 km electrified which is 0.92%

https://en.m.wikipedia.org/wiki/List_of_countries_by_rail_tr...

Batteries are still too heavy and take too long to recharge for most commercial travel by plane. If we had better batteries, planes would become electric.

Hydrogen has an infrastructure problem. Planes aren't designed for holding hydrogen and they would need to be redesigned entirely to accommodate for using it as a fuel. Hydrogen is hard to store and transfer as it tends to embrittle a wide variety of metals. There are also no hydrogen refueling stations near airports, you would have to build all of that infrastructure as well. You might be able to generate hydrogen on demand via a chemical reaction with something like NaOH and Silicon or Aluminum, but I haven't run the numbers to see if that would be technically possible, economically feasible, or safe for passenger travel. Theoretically you could use hydrogen, but it would cost trillions of dollars to get everything up and running without some sort of breakthrough.

For the distances need to be viable in a lot of regions we are pretty close.

Current companies are targeting something like 400km. And that is with pretty conservative design choices along every dimension.

With some real investment that would allow companies to embrace more ambitious designs we could do much more then that.

Batteries can be a structural part of the plane. You can use the airflow to cool them potentially. There are lots of opportunity to do much, much better.

I think the connection between most major capital is around 500km. So an 20-30 seat plane that can go 600+ km is really not that far away as people think.

And this is with batteries that are not really optimized for flight. You can push the charge speed up considerably if you are willing to have less cycles. And it very well might be worth to do that. Even so your total investment in electricity and batteries combined is still gone beat fossil fuel by a wide margin.

If we are talking about investing billion into something, it should be electric planes!

You still have diesel trains ?!

Most of the intercity trains in Ireland are powered by diesel.

I believe there's a long term electrification plan for the greater Dublin area, but I don't see a change from using DMU's for a while.

Caltrain in the Bay Area, the capital of world technology, is still a....diesel train. I can't help but chuckle whenever I see one.

Did you miss the wires strung above the tracks? They're working on it:

https://www.caltrain.com/about/MediaRelations/news/Caltrain_...

It's 2022 today and they estimate to complete the project in 2024. Italy had electrified lines in the 1930s, for comparison. There is really no excuse however you look at it. I guess better later than never.

However, it's moving to electric, with the first electric locomotive undergoing testing now, and the first electric fleet arriving this spring, with fully electric service expected to begin in two years.

Depends on the country. Most of the UK away from London and apart from a handful of main lines is diesel. Elsewhere in Europe, most rural lines still are. It's likely many of these will switch to either hydrogen or battery trains, the latter possibly with shorter stretches of overhead wire to recharge.

Wikipedia shows the percentage of electrified railway for all countries. It's 56% for the EU+UK.

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

A more interesting table would be the percent of electrified vs not passenger service miles delivered. The rail networks has a lot of quiet or disused track.

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