One megawatt of grid storage, 10 big flywheels

Beacon Power says its latest flywheel will provide one megawatt of storage to the electricity grid by the end of the year.

The company's carbon fiber flywheels, which are one meter in diameter, spin constantly at up to 16,000 revolutions per minute--a surface speed of about Mach 2, Beacon CEO William Capp explained Friday. Each 8,000-pound unit can provide 100 kilowatts of electricity for 15 minutes.

George King, supervisor of flywheel assembly at Beacon Power, stands next to the company's 100-kilowatt flywheel.

(Credit: Beacon Power)

Combining 10 of those flywheels will give a utility one megawatt of storage, or 25 kilowatt hours--the equivalent of what a home consumes in a day.

Fifteen minutes of storage may not sound like much, but it's enough to smooth out short-term fluctuations in demand and signal frequency, Capp said.

"These are used for fine tuning to keep everything in balance. The way it's done today is that a dispatcher sends a signal to generators...to increase or decrease output," he explained.

The kinetic energy that's generated from the spinning is converted into electricity when it's needed. Similarly, storage is added to the flywheels by using electricity to make them spin faster.

Utilities are starting to experiment with grid storage as a few technologies start to mature, including flywheels, batteries, and compressed air storage. Storage can prevent outages and store power generated from intermittent sources like solar and wind for times of peak demand.

The next generation of solar thermal power plants will use molten salt to store energy for several hours so that they can continue to meet demand for power after the sun goes down.

Flywheels can react quickly to changes in demand, which is more efficient than bringing power generators up and down, Capp said. He predicted that utilities will invest in them because they help lower their carbon emissions.

"Rather than generating the power using fossil fuels, we'll be recycling the energy," Capp said.

The company intends to combine its 100-kilowatt units into 20-megawatt storage facilities, he added.

[suyts]

Hmm, while I'm not from Missouri, they'll have to "show me". Further, the math seems a little off to me. 1 megawatt = 1000 kilowatts. So if you spend the meg for 15 min, or 1/4 an hr, then you have used 250 kwh with a peak demand of a megawatt. Seems pretty silly to me. One could, if this really worked, create 96 4 tons monstrosities to create a constant megawatt of power, no wait, it requires electric generation to power. If they scale it down significantly, if it works at all, it might be a useful replacement for a capacitor. I'd just love to see one story here that states that the CO2 connection to warming is very suspect and that some company has decided to go forward with coal generation here in the U.S. for cheap and reliable energy that has employed thousands of American workers. For those that seemed to need a nod from our European friends before we do something here, check out Germany, they seem to be doing just fine with coal fired plants.

[William Crow]

The manmade global warming was never about truth. Wikipedia the words "statist" and "fascist" (A harsh sounding word, but accurate for this day and time.). Once you do you begin to understand the left's modern political movement.
Big oil is bad, big coal is bad, government needs to take over healthcare, conservative speech on free airwaves needs to be controlled...the left feels that the government needs to control so much more of our daily lives - hence the words statist and fascist to describe the lefts approach.
By the way...if we have an energy shortage we can conserve our way through most of it.

[raptor310]

If i had a childrens spinning top, or better yet, a dredel or something like that, and it stored 1 Joule of rotational kinetic energy, if i were stop that wheel in 1 microsecond, then the power dissapation would be 1 Megawatt over that milisecond. As to its energy storage capacity . . .

[kgsbca]

@suyts, the article doesn't say that the flywheels can "create a constant megawatt of power", it says they store energy, like say energy that is produced by wind turbines or solar plants. After all, the biggest criticism of these two technologies is that the sun doesn't shine and the wind doesn't blow all day. Efficient and economically feasible energy storage is very important and valuable technology.

For Mr. Crow, even if you don't believe that climate change is being caused by human activity, why don't you worry about the impact on our economy of importing all that oil at $130 per barrel? There are many businesses in the US that are not viable when oil prices are that high. The price of oil is going to shrink the airlines, and then the hotel industry, as less people will be able to afford to fly on vacation. I also found your comments about the "left" and "conservative speech" interesting, to say the least, as the only segment of society that supports energy conservation is the left, and those people and ideas are usually derided by conservatives.

[garthasuarus]

The math was exactly right...25kwh per unit x 10 units = 250kwh. But I don't quite get how we go from an article about a UPS system to a discussion of liberal facism? Seriously?
As for global warming, yeah it's still real and still a serious problem. Get used to it.

[MBSTORE]

finnally common sense on cnet. nice to know that there are still some americans left in this country.

[Zeist]

Conserve is the root of conservative. The left is not the only political movement interested in saving energy. Every business is interested in saving energy because it saves money. Every dollar saved is a dollar in profits. Conservatives in general have been against wasteful government enforced programs that claim to conserve. If you shrink "big government" you will conserve more energy than if you shrink any other "big" industry. Consider that purchasing anything with "government" costs between 2 and 3 times as much as purchasing it through the "market". Many government jobs allow pensioned retirement after 20 years of work - every year after that taxpayers are paying double for that job. Once for the person doing the job and again for the person that is retired. In California it is not uncommon for some government workers to retire with two pensions.

[suyts2]

Golly, I really hate this new discussion format.
To garthasuarus, perhaps it is just semantics, but the articles stated "Combining 10 of those flywheels will give a utility one megawatt of storage, or 25 kilowatt hours--the equivalent of what a home consumes in a day. " One Mw for 15 min does not = 25kwh. I'm not sure why William Crow felt compelled to interject his comments about liberal fascism, I thought we all understood it to be a given. Check the numbers on your GW, we have been expieriencing a very significant cooling trend in the last 17 months. So much so, that we are now cooler than when it was 1980. So, no warming isn't a problem, just like it wasn't a problem all the other times the earth warmed. You should get used to that. Now, given that we have exponentially increased man's CO2 emmissions in the duration(last 28 years), how can one believe that anthropologic CO2 has any significance in the temp of our earth?

[suyts2]

@ kgsbca, sorry, I know, I was using some sarcasm to express my doubts about the supposed product. It, to me at least, would seem as useful selling ballons rubbed against children's hair as electrical storage. Except, the ballons would be cheaper and easier to mount on the transmission line. I agree though, legitimate and serious attempts at large power storage is key to the success of wind and solar power. I just don't see the spinning wheels in a 4 ton machination for 15min of 25kwh as a viable solution to anything other than a capacitor for large electric motors starting up. But that product is already in place.

[kgsbca]

I think it is much more space-efficient than a capacitor. Each flywheel can store 25 KWH, and the average home uses about 250 KWH of electricity per day (according to the article), so if you lived in a sunny area and had access to a lot of solar energy and wanted to store a days worth, you would need 10 of these, about a 7' x 16' space, in the basement or backyard (given the weight of these units, probably not on the second floor). So it's a lot more useful than just a large capacitor for starting electric motors (and it stores 25 KWH, which is 100 KW of power for 15 minutes, not 15 min of 25KWH).

While probably not ready for prime time, it is a great step in energy storage, which is important to the future of renewable energy sources that are not always constant but average out to be plentiful.

I understand that people feel uncomfortable about new technology, and don't see the need to replace the one technology that has been able to last more than a century (oil), but the 8 billion person planet, and its' associated economy, cannot be powered by fossil fuels. Just as our communications technology evolved from carrier pigeons to telegraph to the internet and cellular phones, and transportation technology evolved from horse to trains, cars, and planes, our energy technology needs to get a whole lot better. It's not a left/right or liberal/conservative issue, it is the most pressing economic, political, security, health, and even if you don't believe it or care, environmental, issue of our time. Oil is $135 per barrel, and unlikely to return to the prices we were paying for it just three years ago.

[black_dog_racing]

Here is the math: 25kw for one hour is equal to 1mw for for 15 minutes. A kwh is one kilowatt for one hour. If you choose to use 25kwh in fifteen minutes you have 1 mw. The article says 10 units supply 1mw (they omitted the 15 minutes) or the equivalent 25kw for one hour. A kilowatt is a kilowatt (power) a kwh is a kilowatt over time, one hour(energy). if you have an hours worth of energy you can speed up or slow down the rate. 1kwh= 4kw(15minutes)=.5kw(2hours). From wikipedia: Power and energy are frequently confused in the general media. A watt is one 1 joule of energy per second. So watts multiplied by a period of time equals energy. For example, if a 100 watt light bulb is turned on for one hour, then an amount of energy is used corresponding to 100 watts of power being generated for a time period of one hour, i.e. 100 watts times one hour, i.e. 0.1 kilowatt-hour. Do I think it's a good idea, not really since I know it can be done better and cheaper other ways.

[suyts]

Special thanks to alegr in his reply to black_dog.
"Here is the correct math: 1MW * 15 min = 1MW*0.25 hour = 0.25 MW* hour = 250 kW * hour"
He got it exactly right. The article stated that when 10 units are combined, that it can provide 1 megawatt or 25kwh.
Black_dog got the 100watt bulb analogy right. Let's do the math. 100watts for one hour = 0.1kwh. 10 100 watt bulbs for 1 hr = 1 kwh. 100 100 watt bulbs * 1hr = 10kwh. 1000 100 watt bulbs for 1 hr = 100kwh. At this point, we are at 4 x's the stated 25kwh, yet 1000 100 watt bulbs is only at 100kilowatts of power consumption.
To kgsbca, at this point I'm not sure what is worse the semantic math lesson or a left/right argument. You are correct, it shouldn't be. Eventually, we'll all use something other than fossil fuels. That day is not today. The new tech that allows alternative fueling will come naturally. It doesn't have to be forced. People don't have to starve, we don't have to commit financial suicide , we don't have to lose jobs and no one has to needlessly suffer. Changes should occur only after careful consideration so as not to do additional harm to people that we have already plagued with laws and treaties based not on science but rather science fiction.

[tech_crazy]

Three the key things missing are
1) reliability - this is a mechanical device
2) Safety - this heavy thing is spinning at 16000 RPM!
3) Conversion efficiency - losses due to a) motor to turn the flywheel, b) friction, c)generator to generate electricity

[suyts2]

kgsbca, I absolutely agree, things are out of hand because of the shortages in our various fuel supplies, you are correct again in that the internet didn't just fall out of the sky. However, the internet occured as a natural response to the needs and desires of people and their conditions. No one was forced to use the internet. No one was required to do without another form of media in favor of the internet either. As to the needless suffering, the reason pricing for oil and other forms of energy is escalating is two fold.
First, demand is ever increasing. The population of the world continues to increase and the industrialization of the world continues. As far as I can tell, we are still in agreement to this point.
The second reason is probably where most of the contintion is. Supply, escpecially in this nation, has been purposely withheld. When I say needless, I say it because even though we have enough traditional fuel resources right here in this nation to take us beyond the next few centuries, we don't. We can't. There is an estimated 86 billion barrels of oil off the coast of Florida alone. ANWR, more oil. Coastal Cal. has probably more than Florida. We import 750 mil barrels of oil/yr. We don't have to import oil, we chose to. We, as a nation, could single handingly cut the cost of oil in half for not just this nation but for the world. We have chosen not to.(Even as recently as last week in congress.) We could have built oil refineries for gasoline to keep the price and dependence on gas imports(our friend in Venezuela) down. We, as a nation chose not to. The last one built was in 1976 in La. We sit on more coal than anywhere else in the world. In fact, we could rely soley on coal for our electricity and have enough for several centuries. We choose not to build nuke plants. We choose not to recycle spent rods in the nuke plants. We choose not to use coal as a substitute for gasoline.(They used to in the early 1900's.) The USGS has most of the points I've presented. All of these things and more have served only to cut the supply and subsquently drastically increase the cost of energy and as we are now seeing the cost of even food. To think that all of this was unintentional would be naive. All of it needless. However, there is still time to reverse these insidious policies and correct the unnatural and man-caused energy crisis. We have the resources, we have the knowlege, we have the ability and the infrastructure to do so. Why not.

[open-mind]

From the article:



"Combining 10 of those flywheels will give a utility one megawatt of storage..."



This doesn't make sense to me. A megawatt is a rate of energy usage, not an amount of energy that can be stored. It would be kind of like saying "my friend lives 25MPH away."

[open-mind]

I've often wondered if a flywheel storage device like this would be better (compared to NiMH or lithium-ion batteries) to store and re-use breaking energy in hybrid automobiles. It sure seems that the fly-wheel approach could cost less and probably last longer than batteries.

[suyts2]