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Does anyone have much experience switching their electricity rate plan to a time of use (TOU)? For example, peak rates from 3-8pm, off peak the rest.

I’m curious if this would be a good idea considering I charge on 120 volt every day from around 6pm-7am.
 

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there are many on that topic - let us know if you have trouble doing the setting in the car for the times you need.

FAQ: Time of use electric rates and how to use them to save money
By CarZin in forum Generation 1 Volt (2011-2015)
Replies: 7
Last Post: 10-08-2010, 08:13 PM
FAQ: Time of Use electric rates and how to use them to save money
By CarZin in forum General Motors and General Automotive Topics
Replies: 16
 

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I do this with level 1 charging. In theory it works great, but there have been sporadic reports (including mine) that the gen 2 Volt does not accurately estimate the time it takes to charge the car. I have this problem, and while it's possible to work around the limitations, it is frustrating.

I am not sure whether this is a problem specific to a handful of cars, or to all gen 2 Volts. I get the impression that most people on a TOU plan use level 2 charging, in which case the erroneous charge time estimate either does not occur or is not a problem.
 

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You'll have to look at the plans for your specific utility.
In Detroit, my peak hours are M-F 11am-7pm, so it made sense for me to switch since my whole weekend is off peak.
I did a whole house time of day plan, so it also gets me cheaper electric for the whole house during the night and on the weekend, so I reduce my AC use between 11-7 as well. I have an old (1834) house with 2 layers of brick on the exterior, so it holds the cool very well in the summer until the brick heats up, so I can really cut my costs on AC as well in the summer. I set my thermostat to precool the house from 10-11am, and then set the temperature up so it doesn't run much until 7pm again. It's usually still comfortable (76 or 77) in the house until 7pm when the AC starts running again.

I'm paying about 10 cents per kwH for offpeak, and 16.5 (winter) and 18.5 (summer) for on-peak. The normal rate is 13.5 cents for the first 17kwh and 15 cents for everything above that, so it's not much of a penalty for the off-peak, but a significant discount for the on-peak. I estimate I'm using about 75-80% of my power on off peak rates. It probably saving $10-$15 per month with the time of use rates, but I also don't pay much of a penalty by overriding it and charging if I need to (I did do a level 2 charger, which I think is most helpful in cool climates for preheating).

We have options for metering the car charger only too, but the costs to put in a separate meter and feed for that really cancelled any savings.
 

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I am on TOU. I pay 4.4c per kWh at night to charge it. It is as close as possible to being free.

Charge estimate messes up over time. If you use finish charging the latest with departure times this could be a problem as it doesn't know when to start charging. This is a bug that GM would probably never fix. If you use finish charging earliest and only charge during off-peak then no problem.
 

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I am on TOU. I pay 4.4c per kWh at night to charge it. It is as close as possible to being free.

Charge estimate messes up over time. If you use finish charging the latest with departure times this could be a problem as it doesn't know when to start charging. This is a bug that GM would probably never fix. If you use finish charging earliest and only charge during off-peak then no problem.
I'm also in SoCal and SCE's TOU plan charges $0.12/kWh during Super Off-Peak hours (10PM-8AM). That's as cheap as it gets. Who is your electricity provider?
 

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It may be possible in your area. It may not. There was a pilot program in my area a few years back that was discontinued.

Before you jump in with both feet, consider how your home is heated and cooled, and your lifestyle habits. Where TOU plans are available, the nighttime off-peak reduction is typically accompanied with a daytime increase, and sometimes requires a contract.

So if you have kids or anyone at home most of the day in the summer, your cooling bill could substantially increase. Winter electric heating is also quite pricy, so something to think about.

Remember, the Volt is a relatively small chunk of your electric bill. It may be worth it, it may not, depending on your schedule and when people are at home. If you're single or don't have kids, it could be a huge discount. In other scenarios, it may costing more.
 

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I'm also in SoCal and SCE's TOU plan charges $0.12/kWh during Super Off-Peak hours (10PM-8AM). That's as cheap as it gets
Here we pay 11 cents, 24/7. We don't have TOU at all and I'm sure if we did, it would raise our overall power bill. The lions share of the power we use is for air conditioning and from what I've read, when they implement TOU they cut your off-peak rates, but your regular rate almost always goes up and we use much more in the daytime than at night. The few cents we would save recharging our 3 electric cars wouldn't make a dent in the extra we would pay for A/C

Don
 

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it is no big deal to start and stop Volt charging on a 120 volt charging.

Think rainbird - people have been runing yard water timers for years and it is the same type of control.

the Volt could care less about what caused the power cycle.

About the programming glitch -- when I used the time power rate time options I only looked at start time as I did not want to charge when the sun was up in the summer. That seemed to work.

gen one Volt

other example : some off grid solar people stop charging if solar power level drops or it they do not want to pull power from the solar batteries.
 

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it is no big deal to start and stop Volt charging on a 120 volt charging.

Think rainbird - people have been runing yard water timers for years and it is the same type of control.

the Volt could care less about what caused the power cycle.

About the programming glitch -- when I used the time power rate time options I only looked at start time as I did not want to charge when the sun was up in the summer. That seemed to work.

gen one Volt

other example : some off grid solar people stop charging if solar power level drops or it they do not want to pull power from the solar batteries.
If you must interrupt the Volt while it is charging be sure to unplug the J1772 connector from the Volt's charging port before you pull the power plug on the EVSE. Otherwise arcing can occur at the receptacle, this can damage the plug and the receptacle. I imagine the same would be true if you flip off the circuit breaker, best to do after you unplug the charging cable.
 

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Here we pay 11 cents, 24/7. We don't have TOU at all and I'm sure if we did, it would raise our overall power bill. The lions share of the power we use is for air conditioning and from what I've read, when they implement TOU they cut your off-peak rates, but your regular rate almost always goes up and we use much more in the daytime than at night. The few cents we would save recharging our 3 electric cars wouldn't make a dent in the extra we would pay for A/C

Don
Depends very much on the definition of off-peak.

A big challenge is also having good data on your use. We have smart meters, and I can download data in 15 minute chunks for a whole year, which allows me easily to calculate the best tariff. I have the most extreme tariff.
 

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Most of you are lucky. In San Diego the lowest TOU (super off peak midnight to 6 AM weekdays) is about $0.22/kWhr. I have solar and:

1) I am a net seller during the day (off peak and peak) but SDGE shifted peak to 4-9 PM after best solar generation.
2) Plug into Level 2 at work for "free" and can commute round trip on this charge.
3) Get a $500/year electricity credit for having a Volt.

Without this combination I don't think an EV pencils out very well.
 

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If you must interrupt the Volt while it is charging be sure to unplug the J1772 connector from the Volt's charging port before you pull the power plug on the EVSE. Otherwise arcing can occur at the receptacle, this can damage the plug and the receptacle. I imagine the same would be true if you flip off the circuit breaker, best to do after you unplug the charging cable.
The breaker is at least designed to be flipped live. That's kind of its only job, after all.
 

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the voltage is zero 120 times each sec - just switch then :)

point is zero crossing switching has been available for long time

that said the off grid solar volt charger people use DYI charger cables and can control the pilot signal wire.
 

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The breaker is at least designed to be flipped live. That's kind of its only job, after all.
Though possibly not 300+ times per year.
 

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Most of you are lucky. In San Diego the lowest TOU (super off peak midnight to 6 AM weekdays) is about $0.22/kWhr.

I'm using this plan from SDGE;


EV-TOU-5, a plan for your home and electric vehicle: This new plan is the same as EV-TOU-2 but the Super Off-Peak rate is reduced to just 9¢ kW/h when you pay a Basic Monthly Service Fee of $16. Super Off-Peak hours are midnight to 6 am weekdays, and midnight to 2 pm on weekends and holiday
 

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Whether this is worth it really depends on your utility's plan, and your normal usage. If you get a TOU plan you may also start changing your habits in annoying ways to put things off (e.g. doing laundry at night even though it would be much more convenient for you to do it during the day). You may save a few pennies, but you might lose sleep also.

In general, the Volt battery is not very big. If you empty your battery everyday, 18Kwh x .$15/kwh = $2.7/day x 30 days = $80/month. If you could charge your Volt for free, that's the most you might save. But TOU is not free. And they charge you more on-peak. So you need to create a spreadsheet and run the numbers. My utility actually has a tool to do that for me. I don't come anywhere near emptying my battery each day, and the savings they calculated was around $20/year! Hardly worth it. On top of that, my regular rate is lower than the utility's regular rate, so I'd probably lose money going to TOU.
 
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