Higher than expected electric bill

turtleturtle

turtleturtle

Active Member
Is there a way to see how many kWh the car consumes? Or maybe the charger that came with the car is really inefficient?

I calculated how much more I would spent in energy charging at home and electricity is super cheap where we live. But the electric bill went up almost $100 a month and I barely drive the car other than small errands a few times a week. It almost seems like there’s energy leakage somewhere. I want to compare energy consumed during charging to the increase in the bill.
 
At my 24/7 rate of 15c / kwh a full charge of about 14kwh would cost $2.10. We charge about twice each day for a total of about 20-25kwh = $3 to $3.75 per day. Just doing a simple example makes this 30 days times $3.75 = $112.50/month. Realistically it would be more like $100. This example has us driving a little over 80 miles per day or about 2,500 miles each month.

In our case we have solar so those calculations don't count.

What is your electricity rate TurtleTurtle?
 
We pay $0.09/kWh where we live. No tiering. No off peak charging rates, just flat.

So that would be $1.20-ish for a full charge?

I’f I drive 1k a month, that should be $25-30.
 
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turtleturtle said:
We pay $0.09/kWh where we live. No tiering. No off peak charging rates, just flat.

So that would be $1.20-ish for a full charge?

I’f I drive 1k a month, that should be $25-30.
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Even if you did a full charge every day it would only add up to $36/mo.

Were you in the same house at this time last year? Are you using any other electric devices that could be increasing your consumption?

You could add a kilowatt meter to the outlet that is used to charge the car to monitor precisely why the charger is consuming.
 
120v is slightly more inefficient than 240, but that huge increase does sound like there might be other factors at play. Yeah, you could try a kill-a-watt or similar just to make sure that there's nothing strange going on, or (significant) leakage from leaving it plugged in.

Otherwise, there's no way in the default system to see the power recharge rate for this vehicle. Not in the car, not in the app (unfortunately).

But yeah, good luck hunting down the culprit, that sounds frustrating.
 
Been in the house a few years and went back and checked usage. It’s consistent until we get to the point we bought and started charging the Clarity.

Maybe the car or charger has a short somewhere, or it’s just trying too hard. Using the 110v charger. Is 240v really more efficient?

I’m going to look for a plug that measures consumption; then could isolate if it’s just the car or if it’s something else in the house.
 
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Have you added any other appliances or maybe switched from a gas dryer to an electric dryer? Have a hotter than usual summer? I carefully track my electricity usage and frankly haven't seen any change in my electric bill since I bought my Clarity. I do 95% of my charging at home, using a NEMA 14-50 240v outlet in my garage.
 
Some more napkin math. At $.09/kWh you’d have to use 1111kWh’s to total $100. That would take 2.6 full charges every day of the month.

The OEM charger shuts off once the charging has finished. 240V charging is marginally more efficient.
 
When did you get your car?

Lot's of my neighbors (without electric cars) have been complaining about their bills going up. Working from home and preparing more of your meals from home will do that (if you are because of COVID).

Still, $100 in a place with "super cheap" electricity is weird.
 
Mowcowbell said:
Have you added any other appliances or maybe switched from a gas dryer to an electric dryer? Have a hotter than usual summer? I carefully track my electricity usage and frankly haven't seen any change in my electric bill since I bought my Clarity. I do 95% of my charging at home, using a NEMA 14-50 240v outlet in my garage.
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Appliances and HVAC are the same. Year over year temperatures for the months are comparable.

I am working from home now, but that’s a laptop and two monitors; I don’t think it would account for that much increase. We have a large family here; my +1 didn’t affect the routine much.
 
Landshark said:
Some more napkin math. At $.09/kWh you’d have to use 1111kWh’s to total $100. That would take 2.6 full charges every day of the month.

The OEM charger shuts off once the charging has finished. 240V charging is marginally more efficient.
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Yeah, it shouldn’t be that much of a jump. There’s a bit of a debate in the house on whether or not it’s the car, so the kilowatt consumption meter should settle it. But then if it’s not the car, something weird is going on.

When you say “marginal” are we taking 3-5% more efficient at 240v?
 
Do you have the ability to see daily usage on the utility company's website? Houses here have "smart meters" and I can see hour by hour usage for any day from when we bought the house 6 years ago to yesterday. You could unplug the car's charger for a few days and see if usage is noticeably different. But building on others' calculations, unless you're driving 3500+ miles per month all on electricity that isn't it. And it would be physically impossible to fully recharge 2.5x/day on 120V, much less drive 110 miles also!

The kill-a-watt meter will help confirm what you're actually using; it would be extremely surprising to have a fault in the cable or the car charging circuitry that wouldn't be otherwise noticeable as the car not working...or the cable catching fire.

My money is on something else in the house (refrigerator etc); the kill-a-watt meter can help isolate that too.
 
turtleturtle said:
We pay $0.09/kWh where we live. No tiering. No off peak charging rates, just flat.
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Electric rates can be a little tricky. There are usually other fees that are also proportional to your usage (beyond just the basic electric rate), for instance distribution fees, taxes and such. For example, my "electric supply rate" is 7.2 cents / kWh. But... by the time all the proportional fees are added in, the net rate is 11.2 cents. If you want to predict the differential cost of your Clarity, you need to include all costs / fees that are in your electric bill and are directly proportional to usage.
 
JCA said:
Do you have the ability to see daily usage?

My money is on something else in the house (refrigerator etc); the kill-a-watt meter can help isolate that too.
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The bill doesn’t show actually daily usage, but an average daily usage. Up by 20%.

The meter, if it’s not the car, will be useful to see what other appliances are consuming. Help eliminate them.
 
turtleturtle said:
When you say “marginal” are we taking 3-5% more efficient at 240v?
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Possibly even less. What we sometimes refer to as a Level 1 or 2 charger, is just a cable/extension cord, that connects the charger, which is built into the car, to a source of power. I haven’t measured the difference in electrical consumption between a L1 and L2 device for a full charge on a Clarity. Theoretically, it would take the same amount of kWh’s using either 120 or 240.

There has been some discussion that the components for the battery temperature management system may operate more efficiently when the charger is connected to a 240V power supply.
 
Landshark said:
Possibly even less. What we sometimes refer to as a Level 1 or 2 charger, is just a cable/extension cord, that connects the charger, which is built into the car, to a source of power. I haven’t measured the difference in electrical consumption between a L1 and L2 device for a full charge on a Clarity. Theoretically, it would take the same amount of kWh’s using either 120 or 240.

There has been some discussion that the components for the battery temperature management system may operate more efficiently when the charger is connected to a 240V power supply.
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Let a total electricity ignoramus ask a silly question: Does the time spent charging (12 hours at 120V vs 3-4 hours at 240V) have any significant effect in cost?
 
coutinpe said:
Let a total electricity ignoramus ask a silly question: Does the time spent charging (12 hours at 120V vs 3-4 hours at 240V) have any significant effect in cost?
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Nope. You pay for kilowatt-hours. It doesn't matter whether it takes you a minute or a day to use that kilowatt hour, the cost will be the same.
Of course if you have time-of-day metering, off-peak, or similar, the cost will vary in accordance with the rate periods.
 
MrFixit said:
Nope. You pay for kilowatt-hours. It doesn't matter whether it takes you a minute or a day to use that kilowatt hour, the cost will be the same.
Of course if you have time-of-day metering, off-peak, or similar, the cost will vary in accordance with the rate periods.
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Thank you Mr Fixit. So we could conclude that for a flat electricity rate scenerio the sole advantage of a L2 charger is saving time, not money?
 
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