Posted on 09/04/2007 10:37:19 AM PDT by 300magnum
http://wdef.com/blog/personal_power_grid_offers_next_generation_alternative_energy_today/08/2007
http://www.fuelcellsworks.com/Supppage7578.html
http://www.wpxi.com/station/13657446/detail.html
http://techon.nikkeibp.co.jp/english/NEWS_EN/20070710/135748/
http://www.theautochannel.com/F/news/2007/06/26/053126.html
http://www.worldchanging.com/archives/006979.html
http://www.h2daily.com/content/view/494/50/
Very good! So, when do you think the “Home Fuel Cell” that gets individual homes off of the common grid will finally arrive, 2025?
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It is not 50kwh.
At 15kw to go 60 mph.
To go 500miles at 60 mph it will take 8.3 hrs
8.3 times 15kw is 124.5 kwh.
Batteries discharge exponentially faster as load increases. So you might be able 500 miles at 30 mph using 50kwh but I seroisly doubt you will get anywhere near that at highway speed.
None the less, 45kwh in five minutes is still 900A at 600VDC. Which would mean 4 ea 500kcmil cables. I doubt many people would be able to lift the plug off the ground.
This recharge is not for the faint of heart.
Essentially this storage system is a super capacitor, which is fine by itself, but what happens in an accident and it shorts out? It will be a industrial size plasma cutter.
Probably never. Coal is much cheaper than NG.
A couple of points.
The eestor unit in question is 50 kwh. Whether you can actually drive 500 miles on it is another question.
Second, it is not a battery and will have different discharge characteristics.
Third, 5 minute charges are posible with either very high amperage or voltage. I’m not saying that it is practical.
They claim they have built in safety features to prevent catastrophic discharge for what it’s worth.
1. If it is 50 kwh then you won’t be going 500miles at 60mph. Frictional losses increase with speed.
2. I have been designing power systems for 25 years and elctricity in large quantities is dangerous period. As you pointed out you can either increase voltage or current (VxI=P). 600 volts is as high as you can go to be considered “Low” voltage. 120 volts is really as high as you can go without being almost always lethal.
Past 600V the standard choices are 4160V, 15KV, 30KV, 60KV, 110KV, 220KV and 500KV.
Anyway anything past 600V is pretty scary and that’s why I like electricians so much, I don’t have to touch that stuff.
The problem is that you have to make a good clean contact in air that it is not too dry and not too wet every time you charge. Once the contacts start to get fouled you will get increasing resistance and than comes the snap crackle Ka-pow!
The only way to make it safe is that the vehicle occupants get out and stand behind a concrete blast wall.
If they can be recharged as many times as claimed and only weigh 300 lbs, I think for local driving they will be recharged at home with 240v.
On the highway, battery swap stations could be automated and quick. No harder than driving through a car wash. The dead cells would then be charged in a safe area at whatever rate that makes business sense.
That would be safer. Though part of the change out would have to be contact cleaning. I would also think you could have diagnostics to monitor resistance.
Honestly, I doubt we will see all electric cars based on this design.
However, if they can produce the product at the price point they claim, we will probably see them in hybrid vehicles. Current batteries cannot accept current fast enough to make regenerative breaking very efficient. A 10 kwh cell that weighs 60 lbs and can basically accept and deliver power as fast as you need it would make for a pretty cool car.
Of course if you can blast out that much electric power it may lead to an all electric drive with an on board diesel generator to keep the cell topped off. Solves the rapid recharge problem for cross country driving. You wouldn’t need ad much storage. Could be plugged in at home to trickle charge for routine driving. And would be pretty efficient to boot.
I couldn’t agree more.
Watts is a unit of power. The car would consume (or transform) energy, not power. So, in one hour, this hypothetical car traveling 55mph might consume 4.5 Kwh, or 81 watt-hours/mile.
You are correct. I got lazy. It’s KW/MPH = KWH/miles
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