Posted on 04/05/2015 5:36:33 PM PDT by LogicDesigner
The way I got my number was by starting with the total generation capacity of the United States, which is about one terawatt. If you make a very conservative estimate and say that nighttime demand is only 20% less than peak afternoon demand, that leaves you with 200 gigawatts of unused capacity during the night. If we say that night lasts for eight hours, that gives us 1600 GWh.
Electric cars consume in the neighborhood of roughly 300 watt-hours per mile. If you assume that cars are driven on average somewhere around 40 miles per day, that means the average car would need 12,000 watt-hours, or 12 kWh, of juice to recharge every night. 1600 GWh divided by 12 kWh per car gives us 133 million cars.
Take 133 million and just in case my numbers were off here and there, cut it down to 50 million. I chose to err on the low side just to be safe.
Anyway, it turns out I may have been too conservative. While searching for these numbers, I ran into a couple of articles on the subject:
Don’t Worry: US Grid Capable of Supporting Up to 150 Million Electric Vehicles
The US Department of Energy’s Pacific Northwest National Laboratory calculated that the grid’s excess capacity will support over 150 million pure electric vehicles.
150 million means that nearly 75% of the vehicles on our roads today could be electric and the grid would have the capacity to support them all.
Now the article goes on to say that in order to get the full 150 million, electric cars would have to be distributed proportionally to areas which have the most nighttime capacity. That of course is not likely, so maybe something between my 50 million number and that 150 million number is more realistic.
This article also mentions that 150 million number:
EVs generate new variables for power grids
And this one from MIT Technology Review.
Could Electric Cars Threaten the Grid?
The MIT article's biggest concern is not that our plants can't produce enough electricity, but that some neighborhoods might need to upgrade their transformers if homeowners set their cars to all charge at the same time. But then they make this point:
Electric cars can typically be programmed to charge at certain times, rather than just charging as soon as they’re plugged in. If car owners set their cars to be completely charged by a certain time, say 6 a.m., this has the effect of staggering when cars start charging. The start time depends on how depleted the battery is—to finish at 6 a.m. might require starting at 2 a.m. or 4 a.m., depending on how much charging is needed. So instead of a surge of power demand when people get home from work, the charging is spread out through the night.
All the major electric cars being sold today have the capability to set the charging timer "end time" as described above. With the current trend of electric companies offering "time-of-use" electricity plans that give significant discounts at night, customers will be motivated to make sure they are charging during the times that best suit the grid.
How cute.
The guy who can’t win an argument creates a nasty image to compensate. Let me know if you have anything intelligent to contribute.
Thank you!
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>> “Regular firefighters can handle battery fires just fine.” <<
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You’re out of your mind!
Firefighters handle electric car accidents ‘fine’ by just keeping everyone back until the magnesium/aluminum fire has burned out.
Then they step aside while the wreckers and the road repair crew take over.
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I hope everyone enjoyed the bullshit post!
Our grid is already extremely challenged, and pop-outs happen frequently in neighborhoods where electric coffins are common.
We are all being charged for these costly transformer replacements, even though it is solely the electric coffin nuts that are responsible for the overloads.
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Source please?
I would assume that vast majority of of Americans don't have the means to buy an Accord with cash either. If one follows the 20/4/10 rule, Tesla's are are really only affordable to those in the top ten percent income bracket. A $70K four year loan at 3% is going cost ~$1550 a month. Add in insurance, electricity, maintenance, etc I would think the monthly total would come in around $1850...
Agreed on government subsidy. I'm against it.
There was a financial news channel guest last week who suggested taking out lengthy auto loans and invest any spare cash in stocks..
I kinda agree with this. The only such accident that I’ve witnessed on battery cars....the fire guys put a zone up around the car and waited for an hour or two until they felt it was safe. My impression was they weren’t going to clean up the site...they’d called some hazmat-clean-up crew and were waiting on their arrival. Maybe it differs state to state and maybe some fire departments have training in this area. It’s kind like meth labs being discovered, and firemen won’t be coming into the area to contain the mess....it’s a hazmat-clean-up crew, contracted by the county or city.
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>> “Source please?” <<
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My second son, who is a safety manager for PG&E.
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Ah. So nothing that anyone here except you can verify.
Funny but I have several friends working for Com Ed here in Illinois and they say exactly that. Electricity is over produced at night. In fact the state of Illinois building and several others in Chicago’s loop create ice at night for air conditioning during the day to use the spare night time electricity.
Gas has become very popular recently because it can be turned up and down easily. So many smaller or older coal and Nuclear plants are being decommissioned and replaced with Gas.
While Gas is cheap this works. But its expected that Nat Gas will become more expensive as time goes on. So many of the larger coal and Nuclear plants will still produce the bulk of the power and leave Nat Gas to handle peaks.
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