Yah, I need to look a little more closely at the kwh to lbs of CO2 conversion factor. It might be more like 1.5 lbs CO2 per kwh to the socket in the wall in the states, more like .5 lbs CO2 per kwh in ontario.
Are you assuming that the .5 gallons of warmup does not include any driving?
The conversion using kWh *should* yield the same results as using BTU's.
So converting 1 million BTU to kWh = 293kWh which means that's:
0.77lb CO2 per kWh anthracite coal
0.39lb CO2 per kWh methane NG
which, I will admit does seem low, but I couldn't tell you for sure....
For comparison a gallon of gas has 125,000BTU = 36.6kWh which means:
.546lb of CO2 per kWh
Given the numbers above, that does seem reasonable - it's between coal and NG.
But all that said -- you're probably right about warm days... I'll pay attention the next time I drive to see how much fuel it takes to warm up given the temps outside haven't yet gotten cold (but it's a far cry from the 90 degree summers ).
Of course, I've always been under the impression that power plants are more efficient (in both emissions and production) than our ICE engines I wonder if anyone has done a study on engine wear in the winter with and without a heater....
Time is the best teacher. Unfortunately it kills all its students.
Does the energy used by the heater offset the drop in mpg you see during the first couple minutes of driving?
That's the question... although, I'll include the full morning commute in my analysis since it's pretty short and engines probably keep heating up for 30 minutes when it is cool out even though I'm driving far less than that. When it's cool, not even cold, I'm barely at operating temp by the time I get to the train station.
So Pablo's plugged in tonight with a new engine block heater. The dealer has to remove a sub-frame member to install it because the manufacturer doesn't want to add $5 to the manufacturing cost. So it's 3.5 hours labour making for about a $400 total all in. Youch, but I knew that going in. $1 per watt ironically, as confirmed by the WattsUp meter.
Anyway, I'm hoping to save 13 cents worth of gas each weekday morning by spending 8 cents worth of electricity to do so. My mother used to mention pennywise - pound foolish or something like that, well this certainly is. I reckon the payback is about 40 years assuming 75% seasonal usage.
Anyway, tonight there's no timer involved so it's 32 cents and 11,000 BTUs of warmth for the engine. Watch me get the typical 18 LHK on my first leg tomorrow and see no difference.
Well...don't forget...you are also saving wear and tear on the engine startup by the motor being warmer, your catalytic will last longer...and you will have toasty warm feet sooner (hard to put a price on that one).
What are the environmental costs of a car wearing-out and either needing an overhaul or replacement?
McIntyre's First Law: "Under the right circumstances, anything I tell you may be wrong."
O'Brien's First Corollary to McIntyre's First Law: "I don't know what the right circumstances are, either."
Oh yes... the catalytic converter will really benefit, and therefore the resultant emissions. Good point!
The Accord's getting an EBH soon as well. That could cause big changes because we've always backed in so that we can drive out. I drive in now since I can coats ICE-Off down our little street and roll up to the house - then roll back down to the street in the morning and start up there and drive up the street.
Another point to consider on the GHG scene in Ontario: fossil fuel generation primarily suppors peak consumption. You're warming your engine in off-peak times using base load generation, which is first nuke, then hydro.
Also, you have the choice of going 100% renewable, non-nuke if you want. But then there goes your nickel