UK government considers space-based solar power for 24/7 Solar Generation | Hacker News Reader

UK government considers space-based solar power for 24/7 Solar Generation

energygain.co.uk

27 pointstimthorn28 comments

The US is looking into this too: https://www.geekwire.com/2020/space-force-will-test-solar-po...

But I'm always pretty skeptical of space-based solar power proposals. First, the receiving array has to be really large or the energy density of the beam will be dangerous to birds / planes, etc. Second, utility is limited because we already have a huge fusion reactor in the sky beaming energy to us which we simply need to build receivers for.

> Second, utility is limited because we already have a huge fusion reactor in the sky beaming energy to us which we simply need to build receivers for.

Said fusion reactor's transmissions are blocked by the earth's bulk for half the day on average, including peak demand hours. The rest of the time it can be partially absorbed by cloud cover, greatly increasing the necessity of spare capacity over extremely wide areas.

Space-based solar doesn't have these issues. It has unfiltered sunlight 24 hours per day.

To be fair, this avoids the problem of night (at the cost of the equinox becoming a problem) (and to some extent the weather as well? I forget).

I wouldn’t bank on it, but I’m glad it’s being explored.

Wouldn't need an energy beam if it could be routed through cables on a space elevator, which is another thing proposed by many people to make space exploration easier.

Last time I checked, any sort of cable or elevator to space was impractical, given the strength and density requirements. Has that changed?

Also, a cable would have to attach to the Earth at the equator, which is some distance from the UK.

It has not. Humanity is still a few materials science breakthroughs and a Nobel in physics or two away from a space elevator tether that can operate on Earth. Many have suggested carbon nanotubes, but nobody knows if you can actually practically manufacture a tether out of them.

I really doubt that by the time technology lets us build a space elevator that we would actually find it worthwhile to build it, at least here on Earth.

Instead those resources and technology development would be better used in creating the manufacturing processes needed to operate in space by mining the moon and capturing asteroids.

You don't need a whole lot of manufacturing lifted into space before you can make it self sustaining and growing of its own work.

Id rather put public cloud up there, crunching numbers and putting off heat into space.

Aside from launch costs, isn’t heat management one of the hardest parts about schemes like that? I’m obviously not an aerospace engineer, but I thought the vacuum breaks most heat dissipation schemes

Heat management is indeed difficult in space. You're basically limited to emitting in infrared since things like fans or phase change cooling has no medium to dump the heat to.

No convection or conduction, but you have radiation heat transfer. Not a space thermodynamicist, I wonder if it would work best crunching number in the shade of the earth and then just recharge in the sun.

I heard a talk from the Space Applications Catapult about this a few months back. It isn't online any more, but some I noted some stats at the time. The station would be 1km wide and 4-5000 tonnes in geostationary orbit, producing >2GW. It would beam power down via microwave to a receiving station 3-5km in diameter, so power density would be sufficiently low to not be a danger - "aircraft flying through it would not burst into flames"

Projected cost was about equal to HS2 (about $100bn) for the pilot station but with much reduced costs for subsequent deployments.

> Projected cost was about equal to HS2 (about $100bn) for the pilot station but with much reduced costs for subsequent deployments.

How does this compare to regular land-based Solar and/or offshore wind farms?

It's funny to see SimCity 2000 coming true. Hopefully not the disaster part, though.

https://simcity.fandom.com/wiki/Microwave_Power_Plant

https://simcity.fandom.com/wiki/Microwave_(disaster)

https://www.deviantart.com/canona2200/art/SIMCITY-2000-Micro...

Sounds like a good exploratory step towards reaching the tech capabilities we need to build Dyson spheres (or similar megastructures harvesting energy in space) someday in the far future. I doubt the tech we have now is enough to make anything particularly useful or efficient, but we've gotta start learning somewhere!

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

https://caseyhandmer.wordpress.com/2019/09/20/no-really-spac...

Indeed, space based solar power is always one of those ideas that sounds great until you sit down for fifteen minutes with a pencil and a piece of paper.

The antenna aperture size for effective wireless power transmission in any band with a reasonable atmospheric window needs to be utterly massive. And you can't escape the aperture requirement with a phased-array, either, since you lose a bunch of power to grating lobes (see the "thinned-array curse").

Management consulting companies love getting requests to study this. Again. They get to charge full price, wait three months, and then stick a new cover on the last report they did, and hand it over. It's like free money.

Of course, what the report always says is that it's a really bad idea (because it is), but for not-so-obvious reasons so the client doesn't feel put down. Oh, and don't publish it.

SpaceX's BFR changes the balance some, but not enough.

Unless maybe to power aircraft. You would need a whole bunch of satellites spread way out -- thousands of miles out -- but synchronized into a phased array to focus onto a rectenna on top of the plane. Not carrying a lot of fuel is good for a plane.

Giant solar arrays coupled with space elevators (anyone watch Gundam 00?), please make it true, I'll pay my 3.50 for it.

Funny how I find this on the front page when I made a similar comment a few minutes ago.

Be careful taking anything UK Gov says seriously. They'll launch the satellites for this by climbing magic-bean stalks I imagine...

I misremembered the scene from Robocop. It was a strategic defense laser, not a power laser, that misfired and set 10,000 acres on fire in Santa Barbara.

https://www.youtube.com/watch?v=OEYoY3NwF24 About 4:30 in.

This is long trodden knowledge dating back to the 1960-1970s when NASA studied it.

At Earth orbit you only double the total power/meter^2 and that boost is no where near covering the added cost of space launch for anything (even with SpaceX).

Lol.

If they actually wasted the money on space tech rather than committees telling us what a high school student could work out I'd care less.

High-voltage, direct current (HVDC) electric power transmission systems are a million times more plausible.

It's a nice idea until the beam loses its target for a moment and wipes out Western Europe.

Maybe that's the goal. Brexit 2.0.

Like when the US spent billions to land on the moon, wink wink.

Requirement number 007 addresses that.

This is a joke right?

Why in the world would anyone consider putting solar panels in space when there are still terrestrial rooftops without them?

> “The UK is growing its status as a global player in space...

Post-Brexit UK can't even launch a satellite.

Pre-Brexit UK couldn't even launch a satellite on its own; Blue Streak was cancelled and the only successful launch was after the cancellation.

UK satellite building on the other hand is a very productive industry.

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