this post was submitted on 11 Mar 2024
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Solarpunk technology
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Technology for a Solar-Punk future.
Airships and hydroponic farms...
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That's because we've been stuck with an irrational mode of production that requires too many people and goods to get far places quickly while burning lots of fossil fuel. A more logical system would only have people traveling by jet and helicopter on an emergency basis. People traveling on vacation or non-emergency business should be able to slowly cruise in relative comfort on battery and solar power. Airship ports can be built along the paths of the atmospheric streams and then rail can be used for the next leg of travelers' journeys.
As far as capacity goes that's just a matter of building bigger airships and using relatively cheap hydrogen instead of helium as the lifting gas.
Realistically, the current air travel infrastructure wasn't built on tourism, it was built on serving business needs - freight, personnel movement, meetings, sales. You're talking about replacing that infrastructure, or at least competing with it, while also being dependent on rail infrastrcuture...
In order to grow this airship system will have to offer some substantial practical advantage over the existing one. The thing is, if I'm shipping something and speed isn't important then rail/truck is fine and I don't see airship freight being cheaper than that. So if the airship doesn't fit the fast/expensive use case, and it doesn't fit the cheap/slow use case, then what is the competitive advantage?
There's a practical upper limit to how big these things can be. Regardless of fancy new structural materials, it's a giant gasbag... the larger it is the more of a problem any crosswind is.
It's going to be a long time before any safety oversight group gets on board with this.
Most freight should still go by sea and rail. There's no beating those modes especially if the railways get fully electrified and container ships transition to nuclear power. The case for long distance point-to-point transport of large, special equipment is still there, but I don't think it really changes the world. Rather, the substantial, practical benefit of airships is moving people more humanely and with lower greenhouse gas emissions. Video conferencing and telepresence is good enough these days that there isn't a good reason anymore for people to cross oceans in a matter of hours except in an emergency. Eventually, emissions costs will stop being externalized and at that point airships could fill the fast-enough/cheap use case.
I don't understand what you mean about crosswinds being a problem. Increasing the lifting capacity of an airship only increases the effect of crosswind relatively modestly. That's because a given increase in the relevant cross sectional area of an airship roughly corresponds to a square increase of the volume, which directly correlates to lifting capacity. To think of it another way, any crosswind penalty to increasing the lifting capacity of an airship can be negated by allocating some of that additional capacity to increasing the available thrust of the propulsion system. Therefore, crosswinds become less of a problem for airships as they get bigger.
There are already robust standards in place for working with hydrogen and as of 2022, the EU has adapted their regulations to allow for hydrogen as a lifting gas. It is still prohibited in North America, but the FAA is already giving initial approval for hydrogen fueled airplanes, which of course requires high pressure hydrogen fuel tanks, an arguably riskier proposition than ambient pressure gas cells. Anyway, it seems like one way or another, hydrogen is the future of flight.