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tahanson43206

Moderator

Registered: 2018-04-27

Posts: 19,263

SPS Mechanical Solar Power Satellite Steampunk Vision

This topic is inspired by a suggestion from Calliban, that a mechanical (non-electronic) Solar Power Satellite might be not only feasible, but competitive with popular silicon solar panel vision.

Solar panels are successful in space applications, and they have been for many decades now.

The vision of Calliban would collect power from the flow of thermal energy between a hot plate facing the Sun, and a cold plate facing deep space, where 4 degrees Kelvin is the (approximate) temperature of the background radiation. 

In the vision of a mechanical energy capture system, an efficiency of 50% might be possible.

This topic is offered for those NewMars members who share an interest in non-electronic systems, and who are willing to stretch to imagine a gigantic SPS that uses no electronics at all for it's primary function.

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tahanson43206

Moderator

Registered: 2018-04-27

Posts: 19,263

Re: SPS Mechanical Solar Power Satellite Steampunk Vision

This post is reserved for an index to posts that may be contributed by NewMars members over time.

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tahanson43206

Moderator

Registered: 2018-04-27

Posts: 19,263

Re: SPS Mechanical Solar Power Satellite Steampunk Vision

This topic ** should ** generate some interest outside the small community of active NewMars participants. If I'm right, and there are folks ** out there ** who would like to engage with Caliban in developing a mechanical SPS  concept, please see the Recruiting Topic for procedure.

A well designed mechanical SPS would work ** really ** well closer in to the Sun, since the deep space heat sink is available there and the solar flux is so much greater.

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Calliban

Member

From: Northern England, UK

Registered: 2019-08-18

Posts: 3,777

Re: SPS Mechanical Solar Power Satellite Steampunk Vision

When O'Neill first described SPS, they were steam plants.  Only later was the concept ungraded to PV.  But the two systems would have about the same power density in full sun.  But thermodynamic plants would be mostly steel construction, whereas PV requires polysilicon.  Given the scale of equipment needed to make polysilicon, it isn't clear to me that PV gives better results than a thermodynamic plant.  It is much easier to make carbon steel than semiconductor grade silicon.  And concentrating mirrors and radiators will be no heavier than PV panels.

So why bother trying to make PV?  It makes more sense on Earth, because PV continyes to produce power under diffuse light.  It is also easier for small distributed operations, because it has no moving parts.  But those advantages count for much less with a multi-GW space solar power station.

Last edited by Calliban (2024-10-03 16:35:44)

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"Plan and prepare for every possibility, and you will never act. It is nobler to have courage as we stumble into half the things we fear than to analyse every possible obstacle and begin nothing. Great things are achieved by embracing great dangers."

tahanson43206

Moderator

Registered: 2018-04-27

Posts: 19,263

Re: SPS Mechanical Solar Power Satellite Steampunk Vision

For Calliban re #4

Thanks for the inspiration to refresh memory of those heady days when visions of solar power satellites were in the air, and humans had not yet landed on the Moon. The suggestion that mechanical systems might have been considered early is intriguing and I intend to do a bit of research.  In the mean time, I do feel that it is reasonable to remember Peter Glazer, who is believed to be the first human to secure wide publicity for the SPS concept.

I found an article in Physics World that i hope to paste into this topic, but it's on a different computer. The essential information is that Glaser's concept used solar panels when the concept was first published in 1968.

No doubt patents were filed with SPS designs, so I'll look for evidence of those.

Regardless of what may have been the case in the past, the present is here with fresh opportunities for your vision to receive attention, and hopefully some funding to prove the concept would actually work.

A very small prototype heat engine should be able to prove your concept is valid, and that the efficiency of 50% might be achieved.

I'll make an effort to find any evidence of prior work in this specific discipline.  In the mean time 70+ years have gone by, and humans know much more than we did in those early days.

Please translate your vision into a sketch of a prototyple that can be build and deployed on a Falcon 9 or one of the light lifters on the market these days.

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tahanson43206

Moderator

Registered: 2018-04-27

Posts: 19,263

Re: SPS Mechanical Solar Power Satellite Steampunk Vision

This post is intended to capture a bit of the early history of the SPS idea, as we embark upon a newly refreshed vision of a mechanical solution rather than an electronic one.

https://physicsworld.com/a/space-based- … rgy-needs/

Space dreams
The original concept of solar power from space was dreamt up in 1968 by Peter Glaser, a US engineer at the consultancy Arthur D Little. He envisaged placing a huge disc-shaped satellite in geostationary orbit some 36,000 km above the Earth (Science 162 857). The satellite, roughly 6 km in diameter, would be made of photovoltaic panels to collect sunlight and convert it into electrical energy. This energy would then be turned into microwaves using a tube amplifier and beamed to Earth via a 2 km-diameter transmitter.

It’s the only form of green, renewable energy with the potential to provide continuous, baseline electrical power.

Chris Rodenbeck, US Naval Research Laboratory
The beauty of microwaves is they don’t get absorbed by clouds here on Earth and so would pass largely (though not totally) unhindered through our atmosphere. Glaser envisaged them being collected by a fixed antenna 3 km in diameter, where they would be converted into electricity for the grid. “Although the use of satellites for conversion of solar energy may be several decades away,” he wrote, “it is possible to explore several aspects of the required technology as a guide to future developments.”

The initial reaction was positive in at least some quarters, with NASA awarding Glaser’s company, Arthur D Little, a contract for further study. Over the years, however, the conclusions of subsequent studies into space-based solar power have ranged from cautiously positive to outwardly negative.

All members of NewMars forum are welcome to assist with research. We are looking for any evidence that anyone seriously considered a non-photovoltaic method of capturing solar power.

*** After reading the entire article, which covers current work as well as historical designs, I can report that the authors included no mention of non-photovoltaic solutions.  What they spent a lot of time on is design for continuous service without moving parts.

As near as I can tell, the field is wide open for an inventor who can show that a non-photovoltaic solution is both practical and competitive.0

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