Electric Bill 50% Higher Since Purchasing 2 Months Ago

[yobigd20]

you'll use a HELL of a lot more kWh charging your car at low amps. at least 50% more kWh wasted. you should charge at the highest rate possible for the best efficiency. says so right on the Tesla website too.

Tesla Charging | Tesla Motors

charging at 240V 40AMPS: 99kWh from wall to battery.

charging at 120V 12AMPS: 132.6kWh from wall to battery.

if you're charging even lower than 12 amps, expect your wasted energy to be even higher. You're probably doubling the about of kWh by charging at the low rate that you are. totally wasted. just charge at 40 or 80 amps 240V to bring your electric bill way back down.

 

[amans232]

1. Ok, total kWh used since purchase= 961

2. My rate is approximately 0.10 per kWh from Florida Power and Light

3. Here are some other monthly comparisions:
May 2012 kWh=1262
May 2013 kWh=1290
May 2014 kWh=1505

June 2012 kWh=1604
June 2013 kWh=1490
June 2014 kWh=1462

4. I have not purchased any new computers, AC units, lighting, etc

5. I will be charging at maximal amperage from now on (I guess the maximum mine allows is 30 amps...is this right?)

 

[TexasEV]

5. I will be charging at maximal amperage from now on (I guess the maximum mine allows is 30 amps...is this right?)

If you have a 14-50 installed as you said in an earlier post, the car charges at 40A (80% of what the outlet is rated for). This is what the amp dial would have displayed when you first plugged in your UMC with 14-50 adapter into the outlet. Dial it back up to 40A and it should keep itself there from now on.

 

[InTheShadows]

What about demand charges? You need to look closely at your bill. Usually demand charges are reserved for commercial and industrial meters. However it could be possible. If that is the case and there is no way out of the demand charges and they are around the clock then it might make more sense to lower your charge rate.

 

[Lloyd]

Got my car 2.5 months ago MS60...and my electric bill is up around 50%...here are some stats

2012
July kWh=936
Aug kWh=1959
Sept kWh=1566

2013
July 1068
Aug 1775
Sept 1435

2014
July 1495
Aug 2550
Sept 2129

As you can see, my numbers are a lot higher (kWh per month) than in the years past. I drive about 1000 miles per month, so I didn't expect my electric bill to be 40-50% higher than in years past. Am I doing something wrong? I should mention that I've usually been charging my car at very low amperage (usually between 6 and 10) because I read that this is better for the battery.

Your usage is only up 40%. The rest of the increease is due to your utility company increasing their rates. I had commercial properties with minimal usage doubling with minimal increase in usage in the last several months.

 

[amans232]

What about demand charges? You need to look closely at your bill. Usually demand charges are reserved for commercial and industrial meters. However it could be possible. If that is the case and there is no way out of the demand charges and they are around the clock then it might make more sense to lower your charge rate.

I've been on the Florida section of this forum, and most people say that going with TOU is not worth it, especially since we have much heavier AC demand during the day

- - - Updated - - -

If you have a 14-50 installed as you said in an earlier post, the car charges at 40A (80% of what the outlet is rated for). This is what the amp dial would have displayed when you first plugged in your UMC with 14-50 adapter into the outlet. Dial it back up to 40A and it should keep itself there from now on.

I set it to 40 amps, but the car ultimately is charging around 30 amps

 

[Vitaman]

Not sure about rates where you are but in Georgia the super low EV rates are from 11 PM to 7 AM all year long.
The higher rates that would impact more AC use are 2 PM until 7 PM but only June through September.
That may really spike your bill if you are home a lot during those hours, but you still have to factor in the other 8 months, if your lowest rates are similar to your neighbor to the North.

 

[yobigd20]

Did nobody pay attention to my post? It's a lot higher than it should be because he's charging at very very low amps which is extremely inefficient and increases the total amount of kWh used from wall to battery pack. If he charges at the full 40amps he'll cut the amount he increased in half.

 

[mknox]

Did nobody pay attention to my post? It's a lot higher than it should be because he's charging at very very low amps which is extremely inefficient and increases the total amount of kWh used from wall to battery pack. If he charges at the full 40amps he'll cut the amount he increased in half.

I don't agree with that, and it hasn't been my experience at all. I charge at 16 amps / 240 volts at home because I currently only have a 20 amp outlet in the garage. I have dual on-board chargers and charge at 80 amps at work and at 40 amps at other properties I go to. I meter and track my electricity consumption very carefully and if there is a difference, it's buried way down in the noise of all the other variables like temperature.

To the OP, I am an electric utility VP and can tell you these are the most common questions/complaints we get. People trying to compare what they paid (dollars) over various periods of consumption. The only way to know for sure is to sub-meter your car's circuit and apply your utility's rate to the value you get from that meter. If this is something that really concerns you, or you're simply very interested, I would recommend something like the TED on your car's charging circuit. You can get all kinds of useful stats from a device like this.

 

[GoBlue88]

Did nobody pay attention to my post? It's a lot higher than it should be because he's charging at very very low amps which is extremely inefficient and increases the total amount of kWh used from wall to battery pack. If he charges at the full 40amps he'll cut the amount he increased in half.

Plenty of people said the same thing before your post.

 

[amans232]

Thanks everyone for your help. I will charge at the highest possible amp rating and keep you posted if things don't get better. But first I am going to call Tesla to see why my car is only max charging at 30 amps.

 

[TexasEV]

Thanks everyone for your help. I will charge at the highest possible amp rating and keep you posted if things don't get better. But first I am going to call Tesla to see why my car is only max charging at 30 amps.

That usually means there is resistance in your circuit and the car drops amps by 25% as a safety measure. If you know someone else with a 14-50 outlet try charging there and you will most likely get 40A-- that proves the car charger is ok. Have an electrician check your outlet wiring.

 

[InTheShadows]

Did you try turning it back up to 40?

Ours drops to 30 sometimes if it doesn't get plugged in tight (our kids plug it in sometimes) and then we have to set it back to 40.