unmoderated: Proposed lunar energy storage system

Ian Stirling wrote:
In sci.space.policy Brad Guth wrote:
snip
cost. I suggest that we import bearings, generator/motors, and carbon
fiber or Kevlar arms/containers from Earth to the Moon. Each unit

Adding mass to the system does not help with energy storage.

If you've got a given mass of carbon fiber in 'arms', then you gain
nothing in terms of energy storage capacity by adding extra mass to the
ends.

Sounds like you're saying that if 90% of the system is dead weight, not
contributing to the strength of the system, then we have to slow down,
reducing the stress on the load-bearing fiber components, which reduces
the energy of the system anyway. Got it. So it's a wash: any
spinning, load-bearing parts should be high-strength materials, spun up
to a sizeable fraction of their ultimate strength.

But to reduce launch costs for a massive energy storage system, it
would then make sense to make those high-strength fibers from local
materials, say basalt glass fibers. In the dry lunar environment,
these should have pretty good ultimate strength (see 'Moon Miner's
Manifesto discussions on 'Glax' composite material). Since a flywheel
stores more energy if the mass is farther out, forget arms: spin the
glass fibers into a hollow cylinder, easier to fabricate than
varying-cross-section arms. Suspend the cylinder from Earth-imported
bearings.

wbo; But to reduce launch costs for a massive energy storage
system, it would then make sense to make those high-strength
fibers from local materials, say basalt glass fibers. In the
dry lunar environment, these should have pretty good ultimate
strength (see 'Moon Miner's Manifesto discussions on 'Glax'
composite material). Since a flywheel stores more energy if
the mass is farther out, forget arms: spin the glass fibers
into a hollow cylinder, easier to fabricate than varying-cross
-section arms. Suspend the cylinder from Earth-imported bearings.
wbo,
What "Earth-imported" bearings?
Other than end-stop safety bearings which could also be of a magnetic
nature, there shouldn't hardly be any stinking physical bearings even
if the damn thing amounted to a megatonne.

Even at that, a very slight ceramic and/or diamond/ceramic based
bearing is going to be absolutely impressive since everything is at
nearly zero G.

Might I ask; is LL-1 another one of those taboo/nondisclosure zones
that's top-secret and/or need-to-know?

From LL-1 the flywheel stored energy can flow freely and efficiently
via tether towards the lunar deck or off towards getting damn close to
mother Earth, or easily accomplish both at the same time.

As I's just informed Ian Stirling.

At LL-1 there's nearly absolute zero G and about as much of a nearby
accessible vacuum and thus clean environment as you're going to get
without leaving the solar system.

Thus a 100 megatonne flywheel made extensively of composite basalt and
a few other lunar based fibers and elements such as titanium (which is
entirely doable) is certainly going to store a wee bit more energy than
any one kg flywheel that's spinning at nearly "c", which by the way is
not sustainable nor hardly doable.

At LL-1 there's are no volume nor limitations of flywheel mass, and
there's certainly damn little if any friction via the local environment
nor should there be physical bearings involved. Therefore, a
multi-tonnage flywheel as energy storage is just the best ever ticket
in town, as well as situated along with offer whatever crew(s) the
enormous safety advantage of such being roughly 60,000 km away from
that otherwise reactive and downright nasty lunar deck.

LL-1 and especially of the LSE-CM/ISS is also by far offering the
utmost rocket energy efficient task of getting whatever's terrestrial
or lunar to/from LL-1.
-
Brad Guth

Life upon Venus, a township w/Bridge & ET/UFO Park-n-Ride Tarmac:
http://guthvenus.tripod.com/gv-town.htm
The Russian/China LSE-CM/ISS (Lunar Space Elevator)
http://guthvenus.tripod.com/lunar-space-elevator.htm
Venus ETs, plus the updated sub-topics; Brad Guth / GASA-IEIS
http://guthvenus.tripod.com/gv-topics.htm

In article .com,
wrote:
But to reduce launch costs for a massive energy storage system, it
would then make sense to make those high-strength fibers from local
materials, say basalt glass fibers...

Unfortunately, getting a high-strength material that way -- especially
with simple processes -- is speculative at best.

Yeah, you can build flywheels with lunar materials, but they're likely to
be very heavy for even small amounts of energy storage.
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