Flywheel instead of battery storage?

[SunEagle]

Thanks for the link.
I would say what they are doing is on the bleeding edge of technology, not the cutting edge!

I hope the 5 people hurt will recover. That must have been a lot of force when the flywheel came apart.

[inetdog]

This happened today a couple buildings away from where I work; the whole area felt it.

http://www.utsandiego.com/news/2015/...storage-poway/

Thanks for the link.
I would say what they are doing is on the bleeding edge of technology, not the cutting edge!

[DanKegel]

http://www.utsandiego.com/news/2015/...storage-poway/

Sweet! That must have been a *lot* of quanta of angular momentum

I bet they avoid testing them above ground ever again.

[sensij]

When flywheels go bad...

This happened today a couple buildings away from where I work; the whole area felt it.

http://www.utsandiego.com/news/2015/jun/10/explosion-blast-quantum-energy-storage-poway/

[russ]

Same old, same old - people collecting money and nothing more.

[kwilcox]

Sorry about that. The kickstarter was funded last year. The primary reason I posted the link was because there are some good videos of the flywheel technology being used on it that don't exist on the primary site. What's new about this particular iteration is the harmonic cancellation technology that greatly reduces the accuracy required to spin up a 750 lb flywheel. Less accuracy = less expensive in my book.

[kwilcox]

On the flywheel breakthrough front, I've been tracking this company started by an individual named Bill Gray:


Here's the kickstarter that funded his magnetic bearing effort last year. Some good videos there:


If not Bill, then somebody else. It's only a matter of time before somebody brings inexpensive flywheel technology on line.

Mod note - 1) kickstarter links not allowed - most are huckester stuff and con men or just useless.

2) Links to your site are not allowed without prior permission from user name Jason.

For the flywheels - let just one person make one work then maybe there will be interest - just saying "trust me" like the last guy insisted is not good enough.

Flywheel tech is not at all new.

[inetdog]

But won't the smart grid switch off loads when the wind stops and prevent a grid crash ?

Yup, just individual customer crashes. I could see getting used to that eventually.
Intermittent power is common in much of the world.

[Mike90250]

But won't the smart grid switch off loads when the wind stops and prevent a grid crash ?

[inetdog]

They are providing an annual total kW/m2 which no one uses.

Make that kWh/m² and I will agree with you.

It happens to the best of us....

[J.P.M.]

Ok whoa whoa whoa, I'm terribly sorry if I'm coming across as hard-headed. I'm by no means a veteran solar panel user. But I am an avid astronomer and electrical hobbyist. So I know my numbers pretty well. Think maybe I've generated some confusion on here by how I've put my numbers across and perhaps have been focusing too much on theory and not practice. If one goes back through my posts one will see I've quoted both space figure and ground figures. When claiming annual figures I certainly have taken into account the earth's shape, rotation, latitude, axial tilt, day/night hours, sun angle and average atmospheric conditions. What I haven't taken into account is panel orientation, production characteristics and diffuse light. Based on the 3 months of data I've collected from my own system my numbers seem correct. I have an 880watt array without an MPPT controller so it behaves more like a 650 watt array. Gaisma quotes a June figure for Port Elizabeth of 2.5kwh/m2 per day. My array covers 6m2 and has an efficiency factor of 16%. I won't bore with the calculations but they work out that I should be getting about 2.5kwh per day. I get 3.5 on a sunny day and maybe 1 or so when it's cloudy. Averaged out I can easily agree with the 2.5 figure. Now Gaisma quotes figures of between 7 and 8 for the northern cape in summer and over 3 in winter. Average annual is about 6. Multiply 6 by 365 days of the year and you get nearly 2200. Still very near my original calculations. But then again it's all just theory.

Dave: FWIW, I respect your opinion, and perhaps more than some others, maybe even more than you, understand where your information and logic is coming from. But, IMO, your statements here are a very good example of how a little knowledge can be a dangerous thing. IMO, you are out of your depth. Also, IMO only, you are embarrassing yourself. Your life, your choice. I'll only reiterate my suggestion to get a solar textbook. You have some information. If you're interested, get additional and more professional level info and put all the pieces together. You'll perhaps learn more. And, not that it matters, you may also see where my opinions about the depth of your solar energy knowledge comes from.

Good luck.

[russ]

"The solar constant at Earth's orbit in space varies between 1.412 kW/m² in early January to 1.321 kW/m² in early July. The top of the atmosphere averages 400w/m² between the tropics. At 28 degrees south latitude (Northern Cape) it is 380w/m² at the top of the atmosphere. 380*24*365 = 3328.8kwh/m². Add in an atmosphere and some very occasional cloud cover and 2300 is not a big ask."

That was a nice copy paste maybe but meaningless in terms that are used -

Your last try is a lot more "real world".

[Dave3011]

Dave sorry to tell you your numbers are from outer space. If this is what you believe you are in for one hell of surprise when reality hits your bank account.

Ok whoa whoa whoa, I'm terribly sorry if I'm coming across as hard-headed. I'm by no means a veteran solar panel user. But I am an avid astronomer and electrical hobbyist. So I know my numbers pretty well. Think maybe I've generated some confusion on here by how I've put my numbers across and perhaps have been focusing too much on theory and not practice. If one goes back through my posts one will see I've quoted both space figure and ground figures. When claiming annual figures I certainly have taken into account the earth's shape, rotation, latitude, axial tilt, day/night hours, sun angle and average atmospheric conditions. What I haven't taken into account is panel orientation, production characteristics and diffuse light. Based on the 3 months of data I've collected from my own system my numbers seem correct. I have an 880watt array without an MPPT controller so it behaves more like a 650 watt array. Gaisma quotes a June figure for Port Elizabeth of 2.5kwh/m2 per day. My array covers 6m2 and has an efficiency factor of 16%. I won't bore with the calculations but they work out that I should be getting about 2.5kwh per day. I get 3.5 on a sunny day and maybe 1 or so when it's cloudy. Averaged out I can easily agree with the 2.5 figure. Now Gaisma quotes figures of between 7 and 8 for the northern cape in summer and over 3 in winter. Average annual is about 6. Multiply 6 by 365 days of the year and you get nearly 2200. Still very near my original calculations. But then again it's all just theory.

[Sunking]

Dave sorry to tell you your numbers are from outer space. If this is what you believe you are in for one hell of surprise when reality hits your bank account.

[inetdog]

It is indeed a matter of units.
The OP's original units of kW/h/m² are nonsensical and meaningless.
A reasonable set of units would be kWh/year/m², and it appears that is what he is trying to quote.
His supplemental number assumes a position in space in Earth's orbit which is facing the sun 24 hours per day. When you correct for the insolation at the surface, and the decreased time factor the numbers on the map are plausible.
Just do not confuse the "well known" figure of 1000w/m² with the xxxx kWh/m²/year figure which is confusingly in the same order of magnitude for xxxx. But very different uses!

The latter figure is only useful for comparing to your utility energy usage per year when trying to size a system (such as GTI) to offset your annual power consumption.
PS: I would never call the latter figure "irradiance". Far too confusing.