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World's Biggest Battery Switched On in Alaska
windowpain writes "An article in the London Telegraph describes a 2,000 square meter 13,730 cell NiCad UPS that will provide backup power for the entire city of Fairbanks for up to seven minutes. 'This is enough time, according to ABB, to start up diesel generators to restore power, an important safeguard since at such low temperatures, water pipes can freeze entirely in two hours.' Now if they can just remember to keep it plugged in." Update: 08/28 14:58 GMT by M : A reader notes that the battery has enough juice for 12,000 people for seven minutes, and the city of Fairbanks has a population of over 80,000, so they couldn't keep the whole city powered up for even a minute.
i wonder how long my mp3 player would last on that thing..
MilkMiruku
"each battery weighs more than 12 stones..." :) ), i just found out about that unit of mass (here: http://www.ex.ac.uk/cimt/dictunit/ccmass.htm) and 12 stones is 168lbs or 76.2 kg. :)
if you were wondering about this like me ("what size of stone"
and i thought slugs were the weirdest invention in that backwards unit system...
please convert to SI!!!
What can you do in seven minutes?
You can fix a mistake.
The giant energiser bunny of the apocalypse.
If I seem short sighted, it is because I stand on the shoulders of midgets
...the cheapest bid. Don't forget that Cities and Municipalities operate on a budget, and although Flywheel Energy Storage units may have been more environment friendly and cheaper for long-term maintenance, they were probably far more expensive up-front. Long-term financing isn't often a concern for short-term problems, so my guess is that the 2k sq. ft. battery was the cheapest.
assert(expired(knowledge));
A typical average - at least in the lower 48 - is 1kw/household so 40 megawatts should handle 40,000 homes. For how long? We don't have that info other than the article's claim of 7 minutes. Assuming they got their signals crossed and mean that it can deliver 40 megawatts for 7 minutes then the batteries store 40,000kw * 7 minutes / 60 minutes = 4666kWh of energy.
For comparison, a AA nicad holds ~.75wh or .00075 kWh of energy so based on the preceding assumptions this battery bank is the equivalent of somewhat over 6 million AA batteries.
Another article indicates that the purpose is not to power the entire city but to carry the excess load when a single plant drops off line. Fairbanks does have outside feeds and multiple local plants just like the continental US but it has fewer of each so loss of a plant can cause a proportionately larger swing in the supply. It appears that this battery bank is really a load leveler, not a UPS.
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"You are not remembered for doing what is expected of you." - Atul Chitnis
I submitted this to the Editor on duty, but aparently not in time. Fairbanks has over 80,000 people, not just 12,000 that the battery is capable of supporting for 7 minutes. Alaska is rural, but not so rural that its second largest city only has 12,000 people.
FYI - I had family living in Fairbanks for a while so here is some trivia regarding the weather there:
Everyone must have three plug-in heaters in their car, one for the oil pan, one for the radiator, and one for the battery. All major shopping centers have outdoor outlets to plug your car into while you shop.
In addition to being wicked cold, their is essentially 0% humidity, this results in extremely high risk of static shock. And on a cold day you can actually throw hot coffee in the air and it fall to the ground as instant coffee.
The whole city is built on permafrost, so for any major construction they have to sink pilings into the ground to support the buidling once its ambient heat melts the soil below it.
The city is south of the arctic circle by a couple hundred miles, but there is small mountain nearby that if you drive to the top you can see the sun for 24 hours straigh on the summer soltice. THe favorite solstice activity is a city wide charity run.
In the Winter, there is nearby town that holds an annual statewide contest to guess when the river will melt sufficiently to allow a bouy to float freely. This event is called "break-up".
Work for Change & GET PAID!
Hopefully they have thought ahead with reguards to how they will dispose of this in the future.
I would have to have the worlds largest NiCad leak Cadmium into the Alaskan soil.
Is 7 minutes of not having power so bad?
Ask someone on a ventilator that question.
40MW for 7 minutes = 4.6 MWattHours. A D-cell is 12 AmpHours * 1.5 = 18 WattHours, so this battery pack is equivalent to 260,000 D-cells. A D-cell is 60 mm long, so this is would be a Mag Light 9.6 Miles Long!. Here's an artist's rendering
HIV Crosses Species Barrier... into Muppets
Does it emit a heart-stopping, ear-splitting banshee wail when it kicks in? Because the lights going off just isn't sufficent notice that the power is out...
Ceci n'est pas un post.
One would hope that someone on a ventilator would have their own backup power supply for it, and not rely on the vagarities of the local power grid.
and one year there was a power outage on campus over christmas break. The called out the national guard. No kidding. They had to kick in back up generators and such to keep stuff from freezing up because it was sixty below.
Fortunately the city of Fairbanks was still with power and in a few hours they re-routed power to the University. This wasn't just good for keeping people from freezing in the dorms (the poor sots like me who didn't go home for the holidays) but it was very good for the Cray which was being threatened with imminent condesation...
If the whole city of Fairbanks lost power I wonder how people would have coped. I suppose families would have moved in together. Houses with wood stoves would have been very crowded... I wonder if there's even enough housing with other means of heating to support the whole town?
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Once Fairbanks is hooked up to the Matrix, the other 68,000 people will serve as backup power when the NiCads punk out.
It will also keep your boat battery charged up for your next fishing trip. Note however, that this does not negate the need for some sort of a power filter on your computer. This would allow your gas appliances to work and your microwave.
Now I'm not a Y2K-store-Xyears-of-food-live-in-a-cave fruitcake. I just don't want to be the grasshopper, and I want to provide for my family during outages that seem more common than they should. An extended winter power-outage at -25deg F. adjusted my perspective. All you need is shelter/water/heat/food. Maybe a little love too...
Yes, you can. "Volt-amps" are units of electric power, V*I, where V and I are vectors (the load may be reactive and the V vector and the I vector may not be parallel). If the V and I vectors are going in the same direction, they can be considered scalars and "volt-amps" becomes "watts."
Batteries are rated in "Amp-hour" ratings. That is, they can (to a first approximation), deliver current "I" for time "t" where I*t= the rating. I say "to a first approximation" because the time-to-discharge as a function of current draw is not actually linear, but is really more like an exponential.
Of course, there's some efficiency lost in the DC-AC converter electronics. I don't have a clue what it is; perhaps 80% efficiency is good?
So you have a setup like mine: PC with 500W supply, monitor, printer, speakers. I would recommend NOT putting the printer and speakers on the UPS. Only essential equipment that needs power in order to shut everything down gracefully should be on the UPS.
My monitor eats maybe 50W, and my PC consumes 500W max: 550W worst-case.
According to this page, a APC BackUPS 650 (rated for 640VA), will operate a 400W load for seven minutes. With a perfect 120V output, that (perfectly resistive!) load is drawing 3.333A. With the 80% efficiency I mentioned above, it implies that the battery has an amp-hour rating of about 0.5Ah (500mAh). (0.5Ah * 0.8 eff)/3.333A = 0.12 hours (7.2 minutes).
My 550W load (assuming again that it's purely resistive) will draw 4.6A at 120V. This same UPS (assuming that the switching electronics can handle it!) will operate my machine for 0.087 hour (5.2 minutes), plenty of time to shut down.
So: to find the minimum-sized UPS you need, add up the load of the essential equipment, calculate the required current, and find a UPS with a big enough battery to provide you with a comfortable shutdown time.
Its a problem of electronics. If I run a power plant, chances are I have digital displays, fuel conveyors, sensors, etc all electrically powered. If the plants running, you can use that energy to power yourself. If not, normal operating assumptions are that you have an outside power source supplying plant load at least long enough for your generator to start. In the case of a total blackout, you don't have that luxury.
Now, we can't help that your town can't start a diesel generator in less than two hours. A properly maintained diesel unit should be up running at full output (say 8 MW) at 60 Hz in 30 seconds. Using that energy, we can supply electricity to a larger plant so they can run their controls, and get them going. Your average combustion turbine can start in 5 minutes, and can provide say 50 MW of power. You now have enough energy for 45,000+ people. A small fossil fuel plant can cold start in a couple hours, generates 600 MW, enough for say 550,000 people.
Sign me up, I hate resetting my clocks!
SCO to Hell
Because nicads can deliver greater currents than equivalent NiMH? When delivering full capacity in 7 minutes, you want something with a low internal resistance.
And please note that NiCADs have shown exactly _one_ verified situation that will cause the memory effect: Satellites. The batteries have to be discharged to _exactly_ the same level over and over to show the memory effect.
Most NiCADs suffer from overheating, overcharging, and simple wear and tear (most consumer batteries are designed for ~500-1000 cycles; and deep discharging actually makes things worse!)
NiCADs do have better energy density than most SLAs, but usually in bulk SLAs are much cheaper. NiCADs also have a much higher self-discharge rate. It would be interesting to see the Cost/Benefit analysis.
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