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Two part question:

1. After I'm done charging does it tell me my total kilowatt amount on the gauge cluster?
If so, I assume you would look on your electric bill for the cost per KW?
Do the math, and get your cost per fill-up?

2. What uses more power, the A/C or the heater?
 

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2018 500e
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1. It depends on the EVSE cord you have. The car itself doesn't tell you how many kWh it took on after the charge. For me I have a JuiceBox 40 that will tell me how many kWh the charge took. Some public chargers will give you this information also.

In my latest charge of 10.56 kWh it would cost 10.56x.0727=0.77 cents. My electricity rate per kWh is .0727 cents, really cheap.



2. The heater by far!

Later,

Jake
 

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wow.... 77 cents!
I just have the simplest OE cord, that just has flashing lights.
77 cents is for about a half a battery so $1.50 for a full charge. The most I have used for charging is 18.99 kWh or $1.38 at my electricity rate.

The OE cord works great! Especially if you put a 220 plug on the end and double the charge speed.
 

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2013 FIAT 500e
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1. ..cost per fill-up?
2. What uses more power, the A/C or the heater?
1)

You can estimate $/mi just from your total power bill divided by total kWh on that bill, divide that by 89%*, then divide that by your mi/kWh from the trip gauge. That's your $/mi.


2)
  • Someone measured cabin heater power at about 1kW to maintain room temperature when it was around freezing out (after 5 minutes of 5kW to warm it up).
  • Someone else measured A/C cycling down to about 0.5 to 0.25kW when it was hot out.
  • By comparison, based on their fuse, each seat heater takes less than 72W, or 0.072kW.



* Charger efficiency. EPA says the Fiat's 22.2kWh usable capacity takes 25kWh to fill: 22.2 ÷ 25 = 88.8%
 

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For me there are two ways to get the cost per mile on my electric bill, example one includes like ETS example the base charge plus taxes. The base is a sunk cost that is there whether or not I have an electric car. Just two different ways to calculate the cost per mile, use whatever one makes you smile...

example #1, my power bill is $90.73 ÷ 916 kWh = $0.099/kWh
Divided by 89% = $0.111 for the charger to add 1kWh.
Divided by my trip gauge's 4.0mi/kWh = $0.0278/mi

example #2, my power usage is $66.59 ÷ 916 kWh = $0.0727/kWh
Divided by 89% = $0.082 for the charger to add 1kWh.
Divided by my trip gauge's 4.0mi/kWh = $0.0204/mi
 

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I was oversimplifying, resulting in an overestimate: Good point about the base charge. My bill includes other fees & a "base rate" that I'd be paying even without my EV. Unfortunately my electricity charge shows only "min, + use" as one number, without showing what the min fee is :rolleyes:.

But even the overestimate is WAY less than gas + oil + filters + brakes + smog checks + .....
 

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If you charge at a charging station (like Chargepoint), it will usually tell you exactly how many kWh were added. When I charge at home with the 120V cable, I estimate the kWh by multiplying the % charge added by the total battery capacity, and then can use my electricity rates to calculate the cost (our home electric rates now vary with time of day, so we usually try to charge during off-peak periods overnight).
 

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Using "total battery capacity" would be accurate if you measured your current capacity, & then multiplied by 1.126 to compensate for charging inefficiency*.

It might be easier to use your Chargepoint reading's %-per-kWh to estimate home charger use.


* EPA measured 25kWh of grid power used to fully recharge the Fiat's 22.2kWh original usable capacity.
 
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