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Livermore scientist still reinventing the wheel at 94

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Re: Livermore scientist still reinventing the wheel at 94

#21

Post by voidlogic »

toomuchtodo wrote: post #15
perryh2 wrote: post #8

Earlier quoted context omitted.

Scientists at Lawrence Livermore use a lot of software that I believe is not available to the public (e.g. scientific simulations). Mesquite is one custom LLNL software [1]. MATLAB is very common, but I didn't see much (if any) usage of Mathematica (intern last summer). [1] https://iscr.llnl.gov/annual_report/fy2005/subcontracts/kraf...

If its written by the government, its required to be in the public domain.

I'd bet lots of things at Lawrence Livermore fall under national security and will not be in the public domain for a very very long time.

Re: Livermore scientist still reinventing the wheel at 94

#23

Post by EEGuy »

mc-lovin wrote: post #19
whatshisface wrote: post #14

Earlier quoted context omitted.

"We said, 'To heck with electromagnetic, we're going with electrostatic,'" Post says, laughing. It's clearly not just a normal flywheel, perhaps it can convert some other energy form into electricity? (We call them "generators" don't we?)

I'd guess that phrase refers to how energy is put into and taken out of the flywheel: using electrostatic force rather than electromagnetic.

I'm intrigued by Dr. Post's statement regarding electrostatic rather than electromagnetic force.

When I think of the "motor-generator" component of a flywheel-based energy storage device, coils and magnetic poles and all that electromagnetic to/from mechanical energy conversion stuff comes to my mind.

Electrostatic to/from mechanical energy conversion is known [1] [2], but not to my knowledge known for sustained high power and energy density appropriate for practical flywheel-based energy storage.

Intriguing to consider that Dr. Post's research might be going in such a non-traditional direction as electrostatic motor-generators. Perhaps there are some incremental efficiency gains or design simplifications to be had in using the flat plates, good insulation and high voltages characteristic of electrostatics instead of the big coils, cores and high currents of electromagnetics.

That said, there's no free lunch: No matter which electrical-to-mechanical-to-electrical energy conversion mode used may be, the energy stored remains rotational kinetic energy, thus limited by the same critical physical limitations (failure modes, maximal energy density, maximal power density) of traditional (electromagnetic, to date) flywheels.

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[1] https://en.wikipedia.org/wiki/Electrostatic_motor

[2] https://en.wikipedia.org/wiki/Electrostatic_generator

Re: Livermore scientist still reinventing the wheel at 94

#24

Post by ars »

whatshisface wrote: post #14
ars wrote: post #12

Earlier quoted context omitted.

You can't just generate energy from nothing. A flywheel stores energy, it doesn't create it. So yes, they got something wrong.

"We said, 'To heck with electromagnetic, we're going with electrostatic,'" Post says, laughing. It's clearly not just a normal flywheel, perhaps it can convert some other energy form into electricity? (We call them "generators" don't we?)

Other form of energy? Like what?

Using electrostatics to pump up the flywheel is certainly interesting (I wish the article had even the slightest detail on it), but it still doesn't create energy. (Or collect energy from some untapped resource.)

Re: Livermore scientist still reinventing the wheel at 94

#25

Post by ars »

contingencies wrote: post #13
beambot wrote: post #2

"Energy bills would be essentially zero," he says. I'm not sure how this statement is accurate (or relevant). Flywheels do not produce energy, they store kinetic energy. Other comments... (1) I seem to recall an automobile developed in the 60s or 70s by another National Lab that siphoned off stored power from a flywheel (driven by a smaller motor). IIRC, they had hellish issues with handling since the flywheel create…

The Wikipedia article at https://en.wikipedia.org/wiki/Flywheel_energy_storage claims that, in comparison to batteries, flywheels are not as adversely affected by temperature changes, can operate at a much wider temperature range, and are not subject to many of the common failures of chemical rechargeable batteries. They are also less potentially damaging to the environment, being largely made of inert or benign mate…

The biggest problem is they don't store enough energy. Or in other words, they don't store enough per how much they cost.

The energy capacity goes up linearly by mass, but goes up by the speed squared. So all the effort has gone toward increasing the speed.

But the trouble is that the force on the flywheel also goes up by the speed squared. The only materials strong enough are wound carbon fibers - and they are very very costly.

If you increase the mass instead you need very very large and strong bearings, and they tend to fail. For high speed, low weight, you barely need any bearing at all - magnetic bearings are preferred if you can manage it.

Re: Livermore scientist still reinventing the wheel at 94

#26

Post by waster »

"Independent of his age, he has ideas coming out of his mind minute-by-minute," Yamamoto says. "He's so full of energy from all these ideas he has over the weekend, that every Monday morning he can't wait to call me and talk to me about them."

Sounds like a guy I'd like to know. Also loved the quote about him being like a college student with 60 years of experience.

Re: Livermore scientist still reinventing the wheel at 94

#27

Post by dredmorbius »

nitrogen wrote: post #11
dredmorbius wrote: post #7

Earlier quoted context omitted.

The story leaves a lot to be desired in terms of defining technology and specifying methods. Depending on how you buy/sell power, and if you have access to TOU metering, you could spin up flywheels with cheap power and sell it back when rates are higher. If you've got your own generation on site (solar PV, wind, tidal), you could bank excess energy with flywheels. In terms of storage, flywheel round-trip efficiency i…

Beacon Power produces 25KWh flywheels priced at around $1000 /Wh. Is that really a $25mil flywheel? Or should that have been $1000/KWh? For mobile uses (automobiles, etc.) these problems are compounded. I'm probably demonstrating considerable mechanical naivety with this question, but could you balance multiple flywheels in different directions and orientations to mitigate these problems?

Looks like I had my numbers a bit off. It's $10,000/KWh, putting each flywheel at about a quarter million. The cost data aren't clearly stated and I didn't find my earlier posts on this until just now: https://plus.google.com/104092656004159577193/posts/21sJzeSw...

Flywheels are used in cars, and the current generation of Formula One hybrids includes flywheel regenerative braking designs. While you can offset gyroscopic effects with counter-rotating flywheels, you still have the issues of loading the bearings of the individual flywheels due to vehicle vibration, movement, rotation, etc. Some of this can be mitigated by gimbal mounts, but that introduces increased volume requirements to the design, and avoiding gimbal lock requires four (rather than three) axes of rotation, one of which must be driven. It's one thing to have the flywheel last for the duration of a race, another for it to stand years of use in a private vehicle.

Re: Livermore scientist still reinventing the wheel at 94

#28

Post by contingencies »

ars wrote: post #25
contingencies wrote: post #13

Earlier quoted context omitted.

The Wikipedia article at https://en.wikipedia.org/wiki/Flywheel_energy_storage claims that, in comparison to batteries, flywheels are not as adversely affected by temperature changes, can operate at a much wider temperature range, and are not subject to many of the common failures of chemical rechargeable batteries. They are also less potentially damaging to the environment, being largely made of inert or benign mate…

The biggest problem is they don't store enough energy. Or in other words, they don't store enough per how much they cost. The energy capacity goes up linearly by mass, but goes up by the speed squared. So all the effort has gone toward increasing the speed. But the trouble is that the force on the flywheel also goes up by the speed squared. The only materials strong enough are wound carbon fibers - and they are very…

Thanks for your summary.

The kickstarter project was targeting 15kWh which should be more than enough for a low draw residential setting. For a one-off prototype, they asked for US$50,000 funding.

Let's guestimate that with mass-manufacturing the same product could be built for US$30k, and that's going to provide a probable rated lifespan of around 20 years with zero maintenance.

Contrast batteries, which might cost 30% of that (random figure taken from a solar site) but only last 3-6 years. Sure, they are portable, but they are horrible for the environment and a pain to replace.

I still see a huge market for these.

See also a 1979 presentation from an MIT guy: http://adsabs.harvard.edu/abs/1979STIN...8010639M Technical and economic performance analyses indicate that, contrary to general thought, a flywheel system will be competitive if not superior to more conventional systems utilizing either present day or advanced batteries. This derives from the ability of the flywheel to perform the functions of dc-to-ac inversion and optimal impedance matching between the PV arrays and the load in addition to providing energy storage.

Re: Livermore scientist still reinventing the wheel at 94

#29

Post by dredmorbius »

contingencies wrote: post #18
gcb0 wrote: post #17

Earlier quoted context omitted.

Because you can't shake it.

Surely if it's buried, as seems to be the general consensus for cheapest mode of safe deployment, then it doesn't shake? Also, these have been deployed successfully in cars and on various other types of vehicles (cranes, etc.) so the physical stability issue is certainly not a big one. My high school physics is terrible but the keyword vacuum might have something to do with that. Data centers would be concerned about…

"Surely if it's buried, as seems to be the general consensus for cheapest mode of safe deployment, then it doesn't shake?"

The ground occasionally shakes, depending on where you are.

The Earth also rotates on its axis. And with the speeds and energies with which grid storage flywheels operate, that's a significant engineering concern.

The real killer though is cost / KWh of energy storage. For Beacon's designs it's about $10,000/KWh capacity (not $1000/Wh as I wrote above). Which is high. Liquid metal or molten salt batteries, or simple thermal storage (again, likely salt) could likely compete with this.

Re: Livermore scientist still reinventing the wheel at 94

#30

Post by ars »

contingencies wrote: post #28
ars wrote: post #25

Earlier quoted context omitted.

The biggest problem is they don't store enough energy. Or in other words, they don't store enough per how much they cost. The energy capacity goes up linearly by mass, but goes up by the speed squared. So all the effort has gone toward increasing the speed. But the trouble is that the force on the flywheel also goes up by the speed squared. The only materials strong enough are wound carbon fibers - and they are very…

Thanks for your summary. The kickstarter project was targeting 15kWh which should be more than enough for a low draw residential setting. For a one-off prototype, they asked for US$50,000 funding. Let's guestimate that with mass-manufacturing the same product could be built for US$30k, and that's going to provide a probable rated lifespan of around 20 years with zero maintenance. Contrast batteries, which might cost…

> This derives from the ability of the flywheel to perform the functions of dc-to-ac inversion and optimal impedance matching between the PV arrays and the load in addition to providing energy storage.

We don't need this anymore. This stuff is easy with modern power electronics, so if this is what makes it competitive, then it's not.

I also suspect the reliability is not there yet for 20 year operation.

And it's not like people haven't tried - I've read about a large number of companies that have tried, and yet they all seem to vanish.

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