[expenses3]

No. The best thing you can do with a lot of mass in LEO is construct solar power stations that beam energy down to Earth in the form of microwaves. This is what the second book, Critical Mass, gets into. Receivers on Earth wouldn't provide as much power as solar, but would be much easier to construct and work 24/7, no matter the weather. This would be highly useful for reducing climate change and increasing climate resilience.

[sorcerer-mar]

NASA did a feasibility study of this even accounting for future technology improvements/cost reductions and it doesn't seem to come close to earthbound alternatives, especially nuclear fission.

Nuclear fission is more stable, less maintenance, less risky, less upfront and ongoing environmental damage, less vulnerable to all sorts of risks, and produces way way more energy.

> We find the SBSP designs are more expensive than terrestrial alternatives and may have lifecycle costs per unit of electricity that are 12-80 times higher

https://www.nasa.gov/wp-content/uploads/2024/01/otps-sbsp-re...

[expenses3]

I was talking about having mass in orbit from mined asteroids (or the moon), like the grandparent comment. This survey is based entirely on launched SBSP:

> This study assessed lifecycle cost and emissions based on the following scenario: SBSP systems are developed on the ground in the 2030s and launched to low-Earth orbit (LEO), and then transferred to and assembled in geostationary orbit (GEO) in the 2040s.

Furthermore, one main benefit of SBSP over nuclear is that the receivers don't need to be connected to the grid; each household or piece of infrastructure can have one. This would help manage situations like the power outage in Spain earlier this year or the situation at the start of KSR's Ministry for the Future where a deadly heatwave in India is made 10x worse by coinciding power outages.

[sorcerer-mar]

I see -- so we're going to build an end-to-end solar panel/reflector factory in space, from initial mined materials through to operational energy production and transmission. Color me skeptical.

> This would help manage situations like...

Aren't these situations trivially solvable with batteries if there were political will to be prepared for them?

[pfdietz]

> especially nuclear fission

Since nuclear fission is enbarrassingly uncompetitive on Earth, where is this "especially" coming from? The comment seems to be impeaching the credibility of the study, if it concluded nuclear on Earth would be the top contender non-fossil energy source.

[sorcerer-mar]

> didn't read the study

> study isn't credible based on misreading of a comment about the study

No, nuclear isn't the best in $/TWh, though it is quite close. The reason it's so uncompetitive has to do with the gigantic payback period and the fact that renewables (increasingly) eat into its demand intermittently which lengthens the payback period even further.

But if you include environmental impact, nuclear is absolutely amazing. Which, if you'll recall, was a dimension named as important by the GP: "[space based solar generation] would be highly useful for reducing climate change and increasing climate resilience"

It seems you have plenty of time to form your opinions about what's scientifically and economically sound based on sci-fi novels, but not enough to read the executive summary of a NASA study that actually investigated the proposal at hand.