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Not as in heating the car interior with the heater!;)
I mean that I love how it stays cool when running on EV mode and when I get home and leave it in the garage, it doesn't heat up the whole garage like my ICE cars did. Those things sure give off a lot of radiant heat when they've been running awhile....with my Volt, I can come home, open the hood and place my hand right on the motor and it's barely warm to the touch!
 

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Not as in heating the car interior with the heater!;)
I mean that I love how it stays cool when running on EV mode and when I get home and leave it in the garage, it doesn't heat up the whole garage like my ICE cars did. Those things sure give off a lot of radiant heat when they've been running awhile....with my Volt, I can come home, open the hood and place my hand right on the motor and it's barely warm to the touch!
Just plug it in and the garage heats it when the AC kicks on to cool the battery while charging. I avoid charging mine indoors when it's hot outside and resign to plugging in outside using L1 so I can do projects in the garage before dark. Then I move the car in.
 

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I've noted the same thing while stopped at traffic lights.

All those ICE powered cars have an AC system that's fighting the radiator heat, not to mention the long exhaust system running front to back heating up the interior of the car which the AC is trying to cool.
 

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Volts do produce a lot of heat when charging in hot weather. I've taken to leaving my garage door open till it's done.
 

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Another good reason for 120 v charge...probably less heat generation then 240 v....I wonder if the 12 v.battery gets charged during 8 hrs instead 3-4 hrs, will have longer life, on top of decreased use of the car cooling system...During the winter cold nights the ac fan is in sleep mode with 120,versus 240 charging. Slow but long charge is better then "fast and furious" !!!
 

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On the flip side, during the (long) winter, there's little heat to help thaw the car. Drive it in the garage in the evening with ice and snow on it, next morning still frozen like an ice cube.
 

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At 10,000 feet, there are only 90 frost-free days. A little heat would be fine.
Any snow yet? Monarch Pass was covered last weekend. I've been having to run my rear window defroster this week and used my heated seats three times this month.
 

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L2 charging puts out a lot of heat, if it is 80% efficient and charged at 3.4 kw, that is 700 watts of waste heat on average, which is like a 120 V electric space heater set to low.

The benefit with an EV is you can choose to charge it later, but if my Volt is finishing a charge when I pull my Z3 in, the garage is warm similar to what my Z3 does to heat it up. I think the difference is the heat from an ICE is more noticeable since it is over a shorter time period, where the electric car is a bit more spread out.
 

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L2 charging puts out a lot of heat, if it is 80% efficient and charged at 3.4 kw, that is 700 watts of waste heat on average, which is like a 120 V electric space heater set to low.

The benefit with an EV is you can choose to charge it later, but if my Volt is finishing a charge when I pull my Z3 in, the garage is warm similar to what my Z3 does to heat it up. I think the difference is the heat from an ICE is more noticeable since it is over a shorter time period, where the electric car is a bit more spread out.
L2 charging is at least 90% efficient, it's not 80%.
 

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All gasoline powered engines are "heat engines" and as such, always waste energy as heat. The EV eliminate this because an efficient electric motor only generates heat due to the resistance in the wires and some friction. The same heat release due to resistance applies when charging the battery. That is it!

The more you run your Volt on electricity, the less heat it will release and the more efficient your ride will be. The great benefit of less heat is the lesser degradation of the engine fluids and coolants, which in theory can last the life of the vehicle. The second benefit is the simpler and safer maintenance. In the Chevy Spark EV Owner Manual, as there is no gas engine to generate heat, the coolant is changed every 92,000 miles or ten years! The Chevy Bolt EV may be even better!
 

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L2 charging puts out a lot of heat, if it is 80% efficient and charged at 3.4 kw, that is 700 watts of waste heat on average, which is like a 120 V electric space heater set to low.

The benefit with an EV is you can choose to charge it later, but if my Volt is finishing a charge when I pull my Z3 in, the garage is warm similar to what my Z3 does to heat it up. I think the difference is the heat from an ICE is more noticeable since it is over a shorter time period, where the electric car is a bit more spread out.
Based on what the charger at work reports vs. what the car is reporting I'd have to go with L2 charging being 90% efficient.
 

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It might peak at 90% in perfect charging conditions, but hot summer it will be worse than that since it has to cool the battery. I really notice this on the second charge on a hot day when charging efficiency drops substantially. Point stands that the car is capable of dumping a fair amount of heat back into the garage.
 

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In the "global warming" facts , always blaming ICE cars for producing CO2, as great cause of global warming, but I wonder how much of the heating comes directly from millions of engines at 200F, or by the same token the 7 billion human machines at 98.9 F day and night...
 

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L2 charging puts out a lot of heat, if it is 80% efficient and charged at 3.4 kw, that is 700 watts of waste heat on average, which is like a 120 V electric space heater set to low.
It's not, though. It's about 90% efficient. Efficiency INCREASES with voltage.
 

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It might peak at 90% in perfect charging conditions, but hot summer it will be worse than that since it has to cool the battery. I really notice this on the second charge on a hot day when charging efficiency drops substantially. Point stands that the car is capable of dumping a fair amount of heat back into the garage.
No, that 90% figure is *average*. The facts are out there: http://ieeexplore.ieee.org/document/7046253/
 

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Nope, just checked my 2012, on an HCS-40 L2 station it took 11.9 kwh to charge 9.4 kwh used (as reported by car), or 79% efficient, about 80 F today, after road trip using gas. My Volt is now 6 years old this Sept with 40k miles, spent 3 years in FL and 3 years in IA.

90% is not realistic, not sure why they see such high efficiency. I bet efficiency will be around 70% in winter, curious to see.

It could be accuracy of battery level at start of charge too, I will check OBD2 readings to see what they show.

My hunch is the study doesn't do a complete charge? That last little bit really eats into efficiency. Have to figure A.C. draws about 1.5 kw as well, if it runs for 40 minutes it will eat 10% or more off the efficiency for the charge. The study is still charging at fairly low temps.

For cost of operation I have always figured 13 kwh per charge, err on the high side. I will report back after more charges and cold weather.
 

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Actually, based on what I have read, new 2012 cars tended to show 10.4 kwh used before dropping to around 9.4 kwh after a year. That would drop efficiency from about 87% to 79%, the 87% matches the study for > 4 kwh above 70F. So the question is how to measure the real power to the battery instead of the corrected power shown. The corrected power might remove battery efficiency losses or something, so might display lower than actual power used. Either way it doesn't matter, about 2 kwh is put out as heat into the garage, or about 7000 btu.
 

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Actually, based on what I have read, new 2012 cars tended to show 10.4 kwh used before dropping to around 9.4 kwh after a year. That would drop efficiency from about 87% to 79%, the 87% matches the study for > 4 kwh above 70F. So the question is how to measure the real power to the battery instead of the corrected power shown. The corrected power might remove battery efficiency losses or something, so might display lower than actual power used. Either way it doesn't matter, about 2 kwh is put out as heat into the garage, or about 7000 btu.
I still get as high as 10.4, and as little as 9.4 but I'm convinced it has a lot to do with the rate of consumption. Getting on the freeway and driving 40 miles at 65 allows a lot less to be wrung out of the battery than ambling around town and making several long stops seems to.
 

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Nope, just checked my 2012, on an HCS-40 L2 station it took 11.9 kwh to charge 9.4 kwh used (as reported by car), or 79% efficient, about 80 F today, after road trip using gas. My Volt is now 6 years old this Sept with 40k miles, spent 3 years in FL and 3 years in IA.

90% is not realistic, not sure why they see such high efficiency. I bet efficiency will be around 70% in winter, curious to see.

It could be accuracy of battery level at start of charge too, I will check OBD2 readings to see what they show.

My hunch is the study doesn't do a complete charge? That last little bit really eats into efficiency. Have to figure A.C. draws about 1.5 kw as well, if it runs for 40 minutes it will eat 10% or more off the efficiency for the charge. The study is still charging at fairly low temps.

For cost of operation I have always figured 13 kwh per charge, err on the high side. I will report back after more charges and cold weather.
You have one collection point, and you are assuming that midsummer after a gas trip on an 80F day accurately represents what the charing will look like in November, yes? I'm putting that as 1/115th as credible as the reported results from the IEEE paper, at best.
 
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