101–110 of 220 posts
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anyone else think it would be super damn fun building solar floating homes like this?
I'd be down haha - When do we start?
Doesn't appear to have a payload in the picture. That would add weight & power draw.
Same idea could work with solar powered aircraft.
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I’m a bit puzzled by the economy here. Is creating, lunching and orbiting a satellite really cheaper then flying an airplane? Is it really cheaper to have a decommissioned satellite totally burn up in the atmosphere then reusing parts of an airplane to fix another, recycle unusable parts and put the rest in a landfill? The economics here just seem wrong.
USD2021$15M per Falcon 9 launch (re-used, assuming first launch was paid for by a customer) [0] 60 Starlink satellites per Falcon 9 launch [1] = + USD2021$250,000 in launch costs per satellite (+ manufacturing / ops costs) [0] https://www.elonx.net/how-much-does-it-cost-to-launch-a-reus... [1] https://space4peace.org/starlink-gears-up-to-launch-nearly-1...
And because Starlink is building thousands of satellites it has economies of scale that no previous satellite/spacecraft had.
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USD2021$15M per Falcon 9 launch (re-used, assuming first launch was paid for by a customer) [0] 60 Starlink satellites per Falcon 9 launch [1] = + USD2021$250,000 in launch costs per satellite (+ manufacturing / ops costs) [0] https://www.elonx.net/how-much-does-it-cost-to-launch-a-reus... [1] https://space4peace.org/starlink-gears-up-to-launch-nearly-1...
As a reference a new Cessna 172 is $432,000 [1] and that is not a high tech aircraft. [1] https://www.forbes.com/sites/erictegler/2021/04/28/prices-fo...
A new Cessna vs a used Falcon 9 launch hardly seems like a fair comparison. The cost of the rocket is written off as externalized. The actual satellites are not factored in at all. Really what we are comparing here is the cost of an operation vs the cost of an airplane. The economics still seem dubious.
For those curious about the physics of these aircraft, here's an analysis I did of the same concept. The goal is to determine the smallest aircraft configuration that can indefinitely sustain flight: https://github.com/gusgordon/atmospheric_satellite#readme
nice analysis Is it feasible to operate these at lower altitudes? e.g. can we have solar/air drones posted every 100 miles of interstate highway?!
For those curious about the physics of these aircraft, here's an analysis I did of the same concept. The goal is to determine the smallest aircraft configuration that can indefinitely sustain flight: https://github.com/gusgordon/atmospheric_satellite#readme
Is there a reason you optimized the amount of starting energy in the battery? I know basically nothing about how solar power works, but surely you'd just fill the battery up to 100% with an extension cord on the ground before launching it?
For example, an aircraft could "start" at 50% battery state of charge, then charge to 95% over the course of the day, then come back 24 hours later at 51%, and that would be valid. There are other ways around this, but this is what I came up with at the time.
This is similar to why the starting altitude is allowed to float. The gravitational potential energy of the aircraft can be used as another "battery", but the aircraft is only a valid solution if it's not losing altitude over the course of 24 hours.
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Glide based efficiency crafts absolutely need thick atmosphere. They don't have supersonic jets.
The U2 was subsonic. Also, un-powered gliders can get up to impressive altitudes. https://www.airbus.com/newsroom/press-releases/en/2018/09/ai...
I’m confused by the article and the above comment. Isn’t a glider by definition unpowered?
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Sails have several major downsides, most notably they take up a lot of deck space and cause a boat to tilt to the side. If you’re regularly sailing long distances it’s much faster but top speed isn’t that big of a deal when your living on the boat full time. Other options like kites and wind turbines can work well but they all all significant upfront costs as well as ongoing maintenance issues. Spending that same mon…
> Sails have several major downsides[..] Yes, but it makes less noise.
https://www.amprius.com/2019/10/airbus-partners-with-amprius...
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I'd be down haha - When do we start?
You definitely want to try an English narrowboat before you start. I know people that have done this; it's romantic, but at its least romantic you're living in a not very well insulated damp trailer.