Interesting Links for 09-04-2022

[andrewducker]

1. How Much Land Would Solar Thermochemistry Need to make All Our Aviation Fuel?

(tags:viaDanielDWilliam solarpower airplanes fuel )

2. Ladies and gentlemen: the American criminal justice system

(tags:batman comic law USA )

3. Every misleading statement Boris Johnson has made to parliament since the general election

(tags:BorisJohnson conservatives lies )

4. This Bench Does Not Exist

(tags:chair ai )

5. MPs owe Parliament—and the public—the truth - sign a petition now

(tags:lies government UK politics )

6. Government IT systems break down causing 20 hour queues

(tags:transport food UK trade Europe )

7. Hilarious discussion of children being emotionally devastating

(tags:children funny parenting )

Comments

[armiphlage]

Instead of solar thermochemistry, I suspect the totally bonkers price curve for solar photovoltaics will make it more economical (and scalable) to just add more solar photovoltaic capacity as a separate project from building grid-connected fuel factories using electrolysis and atmospheric carbon extraction.

[andrewducker]

If it requires high temperatures then going heat -> electricity -> heat might not be as efficient as giant mirrors focusing light on a central point.

(Or it might be - not sure of the details)

[armiphlage]

Directly using the heat would definitely be more efficient.

Using photovoltaics would be less efficient, but still could be more economical.

A friend recently dissected an old laser-disc player. The laser discs had data on both sides, but only a single laser read-head. A complex and expensive mechanical system would detach the laser from its mounting, lower it down, rotate it, move it sideways, raise it, move it sideways, rotate it, and lower it down. Mechanical parts were far cheaper than the then-expensive laser.

If we still used laser discs today, a modern player would just have two cheap solid-state lasers, one on each side.

Heliotracking mirrors looked like they would be the future of solar. Mirrors were far cheaper than photovoltaic panels, and the savings more than offset the cost and inconvenience of maintaining the mechanical tracking system.

Now that photovoltaic panel prices are dropping to ridiculously low rates, it's likely cheaper to cover more land with inexpensive low-maintenance static PV panels, rather than use more efficient but higher-maintenance mirrors. From the point of view of investors, those PV panels can be generating revenue immediately, while the fuel plant is being fine-tuned. If fuel prices drop and you shut down production, the PV panels can still sell electricity to the grid. If fuel prices rise, you can keep producing fuel at at night using grid power.

[danieldwilliam]

I think there's an excellent chance that you are right.

I think it is difficult to get very high temperatures using electricity but I'm not sure what sort of temperatures are needed for this process.

There's also something noodling in my head about relative cost advantage, relative location advantage and timescales which I can't quite articulate yet.

[armiphlage]

With electricity, you could put your fuel generating module in an industrial park near an airport, reducing your transportation costs. Your PV panels could be located in an area with cheaper land prices.

You do need much higher voltages to run a high-temperature arc furnace than PV panels generate, but converting low-voltage DC to high-voltage AC is a solved problem.

[danieldwilliam]

With electricity, you could put your fuel generating module in an industrial park near an airport, reducing your transportation costs. Your PV panels could be located in an area with cheaper land prices.

This is very true. Especially given that you have to run cables from the PV plant to the airport anyway.

The solar thermal refinary might work best in Dubai - which has access to desert land and a hub airport.

You do need much higher voltages to run a high-temperature arc furnace than PV panels generate, but converting low-voltage DC to high-voltage AC is a solved problem.

I think it's a different problem with generating process heat but I wasn't paying enough attention when I read the article about it.

[zz]

i was recently watching a youtube video showing all the electric plane research that's happening. would be surprised if that wasn't in use in commercial aviation in 10 years.

[andrewducker]

My understanding is that battery density needs to be 3-4 times higher to make it feasible for medium distance planes.

[armiphlage]

Interestingly, two recruiters recently contacted me for Joby Aviation. They're aiming at the low-to-medium range market.

[danieldwilliam]

Do you have a link handy? I would be interested in watching the video?

[zz]

https://www.youtube.com/watch?v=Kj4PE9uATJA

[danieldwilliam]

Thanks

[andrewducker]

Cheers.

Lots of stuff there about short-range, but only one company looking at Paris-London type of distances, and that one's dependent on a battery breakthrough. Might be a while!

(Be lovely if it did happen sooner though)