90 amps for electric car charge!



Electric cars are certainly not the end-all be-all solution to our problems, although they do offer advantages. A large stationary generator operating steady at near full capacity is much more efficient than a bunch of individual car engines, even if the generator is burning fossil fuel. It also centralizes emissions in one place rather than spewing nasty stuff into the stagnant air in city streets.
If the cost came down, I wouldn't mind having an electric commuter car. I wouldn't get rid of my gasoline car, but for the 16 miles a day I commute, something that could go 40 miles on an overnight charge would let me go to work and back and have enough range to go get some lunch.
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You have a choice. In his hypothetical case of several homes sharing a transformer, you can either design for worst case or ignore it. The latter could very well result in the transformer overloading and the homes being without power. And his point is a very valid one. The existing transformer loads were calculated based on some assumptions of what loads would be in the future and a worst case scenario had to be calculated. I would not be surprised that suddenly having homes where new 70A loads for 4 hours appear could exceed the system design, with his transformer loading being a good example.
As for using a longer term lower current, there are two big problems with that:
1 - The longer it takes to recharge the car, the less attractive these cars become and they become totally excluded from many applications. That's especially true when you compare their operating costs with similar size ICE cars available today, eg hybrids, that have no charging issues.
2 - In today's instant gratification world, I doubt many people are going to want to charge it at less than the maximum. You need to run a new circuit to charge them anyway, so why would you not make it capable of charging at the max? And once you have that 90A circuit, you know people are going to use it. You could discourage this by offpeak pricing. But that gets back to what I said a long time ago, which is that you need to talk about a COMPLETE solution, from energy generation to the point of usage, not just an electric car. Yet, the miracle, clean, green electric car is all the media cares to talk about.
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You're the first residential user that I ever heard of that notified the power company because they were installing a hot tub. In the rest of the residential world, no one is keeping track of what loads get added. You put in a 200amp service and that's the end of the story. If you need more capacity, THEN you call the electric company and upgrade to 300amps.
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It puts me in awe of the power of gasoline when you consider that the equivalent POWER flow through an ordinary filling station hose at the gas station when you fill up your car is measured in MEGAWATTS!!!
Mark
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Right now it's not an even comparison. But I think you'll all agree we're closer to the end of reasonably priced gas than we are from the beginning. No matter how much you think is left it's definitely a finite resource. On the other hand there are all sorts of potential new sources of electricity. Many that are of limited practicality right now have potential to become more practical either because of technology improvements or just volume increase. Most are "green" and do not add to the carbon dioxide load. Like it or not the days of gasoline powered transportation are numbered.
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jamesgangnc wrote:

The SUN is a finite resource!
Just yesterday:
"HOUSTON - ExxonMobil Corp. added two billion barrels of oil equivalent to its proved oil and gas reserves in 2009, or 133 per cent of its production for that year, the largest U.S. oil company said Tuesday..."
http://www.calgaryherald.com/business/Exxon+replaced+cent+reserves+2009/2572312/story.html#ixzz0fnNPrPNg
That is, Exxon FOUND a third more oil than they recovered.

I agree. If you had asked the average New Yorker in 1910 what would transportation be like in a hundred years, with a population increase of five-fold, he'd have probably wondered a) Where would we get enough horses, and b) What would we do with all the horse shit.
I'm personally rooting for teleportation.
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wrote:

No.
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You get permit for electrical work from the local municipality. They usually charge a fee and send out an inspector to make sure the work is done according to code. What does any of that have to do with your claim that the power company routinely gets notified when you add a large residential load like a hot tub? Please provide a cite for that. I'd also welcome hearing from anyone else here that notified the power company that they were adding a hot tub or similar load. You notify the power company when you need an upgrade in the service capacity to the house.
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Complete nonsense. As long as your usage is within your service capabilities you have no obligation to inform anyone of added loads. In some jurisdictions you're required to (though few do) pull a permit for electrical work, though in reality this is for *tax* purposes. The power company doesn't know anything about it. You assume government is looking out for something other than themselves. Laughable.
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The suggestion that the city building/inspection/permitting department talks to the power company, even if they are both city departments (which is certainly not universal, as you suggest).
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...or in fact that there is any reason to do so. The power company knows what the trends are by usage statistics. The certainly don't micromanage planning down to the hot tub. Yes, it *is* laughable.
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Well, there's the confusion right there. Many utilities are in the private sector. For example, my "city" is Pittsfield Township. My electric utility is DTE Energy, a publicly traded corporation.
Cindy Hamilton
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Bob F wrote:

I've never lived anywhere where "the power utility is the city", so you are laughable.
--
Greed is the root of all eBay.

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On Wed, 17 Feb 2010 16:00:58 -0500, "Michael A. Terrell"

The city here has the power company, but I assure you that their planning tsars aren't counting hot tubs. Tax assessors, OTOH...
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On 2/17/2010 1:00 PM Michael A. Terrell spake thus:

You've never heard of municipal power companies? Lessee, not far from where I live, Palo Alto, Sacramento, and several others I can't think of just at the moment run their own power systems within their cities. Marin County just decided to set up a county-wide power authority. So yes, in many places "the power utility is the city".
Now who's laughing?
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David Nebenzahl wrote:

Yeah, but that's California where the word for government ownership of the means of production is "normal."
Now my city owns the water system - and makes a small profit. The real reason for city ownership, I've been told, is so the city can keep up with buildings and so forth for tax purposes.
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Several cities in that greatest of red states, Texas, own their electric utilities, including the capital, Austin (a blue island in a sea of red). Also, Garland, near Dallas, as red as you can get.
OK, when did red shift from liberal pinko commie red to god fearing conservative red?
-- Doug
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Douglas Johnson wrote:

When one of the TV networks news department painted a large US map on the floor of their studio and chose red and blue for the two major political parties for a presidential election. We know how liberal most of MSM is.
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Douglas Johnson wrote:

I think it comes from the usual reaction of progressives when they don't get their way: the hold their breath until they turn blue (sometimes accompanied by foot-stamping).
Conversely, conservatives maintain a healthy pink constitution. Sometimes aided by home-made alcohol.
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David Nebenzahl wrote:

I didn't say that. Read it again.

Doesn't say they aren't the same in some places, but it does say it isn't true everywhere. Two cities near me by bulk electric, then rip off residents and business by doubling the cost to everyone else in the area.

Me, at you for your very poor reading skills.
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