Flywheel instead of battery storage?

[ChrisOlson]

Flywheels - Dead as can be.

Oh no - our little grandson has a flywheel powered car. He pushes it on the floor and gets it wound up, then lets it go and it crashes into the wall, or a pile of blocks, sometimes runs it up a ramp and it flies off the end. He has great fun with it.

[walltr8der]

Being an engineer in my day job I have learnt over and over again that the simplest solutions are always the best.

By their very nature batteries are complex, hence their need to be mollycoddled so much. Nothing can be simpler than accellerating mass to store energy. The problem as always is that we humans haven't figured out how to do it "simply and effectively" yet.

"Two brains are better than one", and therefore 10's to 100's or even upwards of 1000 should be far better. The more people we get thinking about it the more likely it is that some genuis somewhere will give it enough thought to have that eurika moment to make it work.

I don't claim to have found any secret or disruptive technology, but I do hope to stimulate a discussion that may in turn stimulate some of the brighter minds on this planet - some of the minds possesed by the likes who invented the lightbulb, the internet, photovoltaics etc. Then maybe one day hairy-arsed engineers like me would no longer have to suffer the endless frustrations associated with batteries...

Check out http://ess-epowervault.com/ I think you will be impressed

[walltr8der]

Being an engineer in my day job I have learnt over and over again that the simplest solutions are always the best.

By their very nature batteries are complex, hence their need to be mollycoddled so much. Nothing can be simpler than accellerating mass to store energy. The problem as always is that we humans haven't figured out how to do it "simply and effectively" yet.

"Two brains are better than one", and therefore 10's to 100's or even upwards of 1000 should be far better. The more people we get thinking about it the more likely it is that some genuis somewhere will give it enough thought to have that eurika moment to make it work.

I don't claim to have found any secret or disruptive technology, but I do hope to stimulate a discussion that may in turn stimulate some of the brighter minds on this planet - some of the minds possesed by the likes who invented the lightbulb, the internet, photovoltaics etc. Then maybe one day hairy-arsed engineers like me would no longer have to suffer the endless frustrations associated with batteries...

Check out http://ess-epowervault.com/ I think you will be impressed!

[walltr8der]

walltr8der

One of the biggest headaches of managing any off-grid solar electric system is the batteries. The need to ensure lead acid batteries regularly reach a 100% state of charge to avoid an early grave can be daunting. Ensuring they reach this 100% state of charge often involves wasting PV power during the absorbtion stage so as to ensure the voltage does not drop too low. Without a very clever management system this inevitably leads to wasted amps!

Professional flywheels aligned parallel to the Earth's axis of rotation have comparable energy storage capabilities of lead acid batteries with an almost limitless cycling capability and no need to reach 100% SOC before discharging to prolong service life. There is no need to check weather forecasts to plan your energy use the night before for fear of using too much power and not having enough sun the next day to charge your batteries! You can simply withdraw whatever was stored in the flywheel and that's that.

I have not checked what the cost of such an energy storage system is nor whether or not it is feasible to DIY.

Inherent dangers are obviously explosive destruction due to overspeed or manufacturing defects. locating the flywheel underground could perhaps best deal with those risks.

Has anyone ever given this much thought? Are the costs perhaps far too high?

check out http://ess-epowervault.com/ I think you will be impressed!

[walltr8der]

walltr8der

I worked at a company that had a small (30kw) flywheel system to "ride through" very short duration power dips (maybe 2 a year). The cost for that system (in the late 80's) seemed more economical than a battery UPS system considering the few times it was needed and the cost to maintain and replace batteries.

Big issue with flywheels is friction. Put one in a "zero gravity" environment and you may have something that works.

Not true at all!!..I'm with Energy Storage Solutions and we have developed a FESS that does not heat up. Got some guys from MIT and Texas A&M. Prototype works.. Gens and re-gens for as long as we want it to without a thermal problem As fas as we know, nobody else has anything like our flywheel...

[russ]

Whew - I'm glad you feel that way. When I re-read what I wrote, I think I came across like a real jerk. I apologize to everyone.

We understood - you were just trying to go in a useful direction.

[PNjunction]

No. I was trying to convince the OP that a Flywheel is not viable energy storage solution. And yes I think LiFePo4 batteries are a very good way to store energy.

Whew - I'm glad you feel that way. When I re-read what I wrote, I think I came across like a real jerk. I apologize to everyone.

[Dave3011]

Flywheels - Dead as can be.

Possibly graphene is an answer. Supposed to be wonderful.

If no one has figured out how to use flywheels by now i doubt they will. What you have to think of to place this in context - energy storage is worth trillions to generators - it could turn baseline power into something of far greater value.

Use in RE is kind of a very small niche - nothing more. For that matter, solar PV is the same thing.

Big companies are spending vast amounts on energy storage - don't get caught up thinking you have found some secret that no one else knows about.

Being an engineer in my day job I have learnt over and over again that the simplest solutions are always the best.

By their very nature batteries are complex, hence their need to be mollycoddled so much. Nothing can be simpler than accellerating mass to store energy. The problem as always is that we humans haven't figured out how to do it "simply and effectively" yet.

"Two brains are better than one", and therefore 10's to 100's or even upwards of 1000 should be far better. The more people we get thinking about it the more likely it is that some genuis somewhere will give it enough thought to have that eurika moment to make it work.

I don't claim to have found any secret or disruptive technology, but I do hope to stimulate a discussion that may in turn stimulate some of the brighter minds on this planet - some of the minds possesed by the likes who invented the lightbulb, the internet, photovoltaics etc. Then maybe one day hairy-arsed engineers like me would no longer have to suffer the endless frustrations associated with batteries...

[russ]

Flywheels - Dead as can be.

Possibly graphene is an answer. Supposed to be wonderful.

If no one has figured out how to use flywheels by now i doubt they will. What you have to think of to place this in context - energy storage is worth trillions to generators - it could turn baseline power into something of far greater value.

Use in RE is kind of a very small niche - nothing more. For that matter, solar PV is the same thing.

Big companies are spending vast amounts on energy storage - don't get caught up thinking you have found some secret that no one else knows about.

[Dave3011]

Interesting to see all the enthusiasm to flywheels despite the fact that its not yet a viable alternative to batteries for home scale energy storage.

It's a pity though - kinetic energy storage has so many theoretical advantages of chemical energy storage, just to name a few:
1) highly flexible charge and discharge rates
2) limitless cycles (limited only by the manufacturing quality)
3) no need for inverters, only frequency and voltage regulation
4) life not affected by state of charge or temperature

Yes explosive destruction is a big danger but then how safe do scuba divers feel working around large canisters containing upwards of 300 atmospheres of "spring loaded" presure contained only by several millimeters of aluminium???

Some awesome facts about kinetic energy are:
1) energy stored increases by the sqaure of velocity - a given mass travelling at 2m/s has 4 times the energy of the same mass travelling at 1m/s
2) The kenetic energy of the Earth in its orbit around the sun equals the entire energy output of the sun over 82 days - not to be scoffed at for a mass of only 1/333000 not powered by nuclear fusion!

[Ian S]

At that same time I was wet-behind-the-ears budding mechanical engineer, still in college at the University of Minnesota. We built a concept flywheel powered car with the wheel in a vacuum case and mounted the whole contraption on a Chevy Chevette chassis with a hydrostatic drive to the rear wheels. The flywheel weighed 3,300 lbs, was mounted laterally, had compressed air bearings, and we had blocks in the suspension to hold the weight and the tires looked like they were flat.

It took two hours to spin it up and we drove the car to the Minneapolis-St. Paul International airport, then turned around to drive it back to the campus engineering shop. It was in winter and we came down a hill and the forces from the flywheel made the front wheels on the thing loose traction and couldn't steer it. We crashed it - went thru a chain link fence and down an embankment and plowed into the snow in some brush. The housing on the flywheel got bent and contacted the flywheel and sparks started coming out of it when the air got in. We figured it was going to blow so we bailed out and then stood around watching it. It took about a half hour to get it to finally come to a stop and the hydro pump and motor were driving the rear wheels all the time

That was the end of flywheel experiments. Yeah, the concept has been around for a long time. It definitely don't work in an automotive application.

Edit:
Ian - forgot to mention that flywheel was donated to us by Bendix Corp. 1981. Bendix didn't totally pass on the idea. They built 10 or 12 of 'em and donated 'em to engineering universities for research purposes. After it was damaged we had to return it to Bendix. It was based on, and basically a bigger version, of their inertial engine starters back in the day.

LOL! That must have been fun, Chris. Bendix was an interesting company in those days. The whiz kid William Agee had taken over as CEO and was trying to shake up what was a stodgy company mostly by spending on a new R&D center and pursuing high tech acquisitions in the aerospace sector - not to mention a beautiful underling, Mary Cunningham. When he went after Martin Marietta, the latter turned around and, in the so-called pac-man defense made a tender offer for Bendix. Both companies wound up with a majority of the other's shares! The stalemate was broken by Bendix being taken over by Allied Corp, a chemical company, while MM stayed independent. Allied eventually acquired Signal to become Allied-Signal then merged with Honeywell and took on that name. I still have some Honeywell stock that was originally part of my profit sharing plan. A good solid company today.

[ChrisOlson]

Circa 1980, I was part of a research group at Bendix Corp. looking into potential projects in the area of advanced composite materials. One of those considered was using high performance composites in flywheels for energy storage. Ultimately, we passed on that but it's interesting how far back flywheel energy storage development goes.

At that same time I was wet-behind-the-ears budding mechanical engineer, still in college at the University of Minnesota. We built a concept flywheel powered car with the wheel in a vacuum case and mounted the whole contraption on a Chevy Chevette chassis with a hydrostatic drive to the rear wheels. The flywheel weighed 3,300 lbs, was mounted laterally, had compressed air bearings, and we had blocks in the suspension to hold the weight and the tires looked like they were flat.

It took two hours to spin it up and we drove the car to the Minneapolis-St. Paul International airport, then turned around to drive it back to the campus engineering shop. It was in winter and we came down a hill and the forces from the flywheel made the front wheels on the thing loose traction and couldn't steer it. We crashed it - went thru a chain link fence and down an embankment and plowed into the snow in some brush. The housing on the flywheel got bent and contacted the flywheel and sparks started coming out of it when the air got in. We figured it was going to blow so we bailed out and then stood around watching it. It took about a half hour to get it to finally come to a stop and the hydro pump and motor were driving the rear wheels all the time

That was the end of flywheel experiments. Yeah, the concept has been around for a long time. It definitely don't work in an automotive application.

Edit:
Ian - forgot to mention that flywheel was donated to us by Bendix Corp. 1981. Bendix didn't totally pass on the idea. They built 10 or 12 of 'em and donated 'em to engineering universities for research purposes. After it was damaged we had to return it to Bendix. It was based on, and basically a bigger version, of their inertial engine starters back in the day.

[Sunking]

Well let's see. Flywheels have been around since batteries and were the first UPS around. Then came inverters and thus the death of Flywheels.

[SunEagle]

Ah, ok. Flywheels it is then.

I'll back out. To save a lot of thread drift, even though the Op seemed genuinely interested in lifepo4, you can continue here:

http://forum.solar-electric.com/showthread.php?23898-GBS-LiFePo4-20-and-40ah-batts

Off to the flywheel store!

No. I was trying to convince the OP that a Flywheel is not viable energy storage solution. And yes I think LiFePo4 batteries are a very good way to store energy.

I just read an article about the new 14.5MW solar array in Anahola HI. Along with the PV array they will be installing a 6MW Lithium-ion battery energy storage system. That is one big battery.

[Ian S]

Here's one potential approach if it can get beyond a prototype. Needs a vacuum of course for reduced friction.

Circa 1980, I was part of a research group at Bendix Corp. looking into potential projects in the area of advanced composite materials. One of those considered was using high performance composites in flywheels for energy storage. Ultimately, we passed on that but it's interesting how far back flywheel energy storage development goes.