[zebraitis]

All,

Found something out about Time-Of-Use (TOU) charging.

I have my Bolt set up to take advantage of the reduced charging rates at night. (In Colorado, I'm in the Beta program with Xcel Energy).

Usually, I plug in my car, and I see the long green blink on the Bolt, meaning, connected, communicating, but delayed.

Well, this morning, I plugged it in, and it started charging right away! NOT the behavior I expected!!

I checked to see if it recognized that I was at my home charging station (it did). I checked to see if the low cost TOU was still entered (it was), I checked to see if it was still programed to charge ONLY during the lowest TOU rate (it was).

But STILL it was charging, and telling me that it would be dome charging at 4:30pm... meaning that it would continue to charge during the highest rate time.

I was about to type this up to the forum and ask if there was any update or software behavior that would cause this.

And then it finally hit me: The reduced rate was 9:00pm - 9:00am. and I was plugging it in at 8:15am.

SO...… it WAS charging at the reduced rate time, just like expected... BUT once it starts charging, it keeps charging and doesn't stop (I checked that at 9:30am, still going).

Unplugging (and receiving an interrupt text message) and then plugging back in allowed for the process to reset. Now the charge would not begin until after 9pm.

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tl/dr: If you are using TOU charging, don't plug it in in the morning unless you want it to charge all day. Wait.

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[Sperling3]

You have to set the preferred charging time in your Bolt to match the preferred TOU charges that your utility uses. For Northern California (PG&E) there are three different tier rates for TOU charging and these times vary on weekends and weekdays. Took a bit to figure how to set on the Bolt, but it does work.

 

[SparkE]

I *think* (I'd have to go back and read the manual to be sure, and I'm not going to) that there is (or 'may be') also an issue of the state of charge (% full) of the battery. If the battery is less than 40% full, then even with delated charging the car will charge up to 40% immediately, then stop charging and wait until the preferred rates are in effect. There is a preference for this, I think.

 

[Bolt Action]

Another consideration is the setting for 'Departure' time. If your TOU is 9 PM to 9 AM, and you had set the departure time for, say, 8:30 AM, and if you plug in at 8:15 AM on a holiday, and you will need 3 hours to fully charge, will the software recognize the shortfall of available time? Will it stop charging at 8:30 AM or 9 AM? Or would it continue to a full charge?

 

[Edchris]

I *think* (I'd have to go back and read the manual to be sure, and I'm not going to) that there is (or 'may be') also an issue of the state of charge (% full) of the battery. If the battery is less than 40% full, then even with delated charging the car will charge up to 40% immediately, then stop charging and wait until the preferred rates are in effect. There is a preference for this, I think.

Yes, it’s a simple button selection. ON will charge to 40% no matter what time it is.

Unplugging (and receiving an interrupt text message) and then plugging back in allowed for the process to reset. Now the charge would not begin until after 9pm.

You have to be careful with that. Let’s say you need juice, but your Bolt is set up to only charge during off peak hours. If you plug it in, it won’t charge, BUT, if you unplug, then replug, (within 5 seconds IIRC), it will override the settings, & start charging cable immediately.
I too found programming three daily, + w/e, + winter hours to not be as straightforward as other programs I’ve used.
My home EVSE, a ChargePoint CPH25 WiFi Takes care of that. During setup it asks for your utility name, digs up all that Companies plans, then asks you to select which plan you subscribe too. It then “knows” when offpeak times are for your particular plan. In my case this includes weekends & holidays, winter & summer.
It also knows the Kwh price, along with delivery charge & tax. It sends an entry to the phone app, which keeps a running track of your Kwh & cost. If you use a public ChargePoint station you get the same info, (showing Free for mist of the public stations around here).

 

[zebraitis]

You have to set the preferred charging time in your Bolt to match the preferred TOU charges that your utility uses.

@Sperling - Thanks, but that was not really the issue that I was having. The issue was that I was surprised that it stated charging in the morning (which was actually my issue, as the Bolt was programmed correctly) and then the interesting part is that if it DOES start at a lower rate time and is not fiully charged that it does not stop. It continues to charge during the higher rate time.

I *think* (I'd have to go back and read the manual to be sure, and I'm not going to) that there is (or 'may be') also an issue of the state of charge (% full) of the battery. If the battery is less than 40% full, then even with delated charging the car will charge up to 40% immediately, then stop charging and wait until the preferred rates are in effect. There is a preference for this, I think.

Yes, but... the 40% charge is a setting ("Departure & Rate"), but that is not this. This was just being surprised by my plugging it in at 8:30AM, and expecting it not to do anything... and much like any other computer / software it was doing exactly what I had told it to do. (D'oh!)

You have to be careful with that.

Respectfully, I would disagree.

Your solution is that you used the intelligence in your EVSU (charger) to manage time of use. I chose to use the Bolt to manage time of use. (… as God and Chevrolet intended! 0 )

When using the Bolt to manage time of use, I found that:
1) If I plug it in NOT during the TOU rate specified by me and stored in the Bolt, it waits. (as it should)
2) If I plug it in DURING the TOU rate specified by me and stored in the Bolt, it charges.

My Low rate programed into the Bolt in 9:00PM - 9:00AM.

So, when I plugged it in at 8:15 AM, it started charging as it should... but (in my flawed human mind) I was expecting it to wait until 9:00PM. That is what caught me off guard.

Now, when it STARTS charging at that time... the interesting thing is that it want to continue charging and ignores the rate going higher after 9:00AM.

As SparkE suggested... maybe it only will continue to charge to 40%, somehow making the assumption that if I plugged it in at 8:15AM then I must obviously want at least SOME charge to go to the battery.

And that, I have not tested.

However, I do know that when it WAS plugged in at 8:15AM, and when I saw that at 9:30AM it was still charging... that when I momentarily unplugged and plugged back in ("re-plugged"?) it then did not start charging again immediately but did wait until 9:00PM. And I was OK with that.

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