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Curious to see if Bolt owners are monitoring how much electricity they are using to charge at home.

I use the iDevices Outdoor Switch.

It works for me because I can't install a Level 2 charger at my apartment. Plus, I can set timers for charger usage.

Do you monitor your energy usage? If so, what do you use?

https://store.idevicesinc.com/idevices-outdoor-switch/
 

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I've used a Kill-o-watt dumb monitor, a TPlink and EdiPlug WiFi monitor on 120v. Not many good/cheap options for 240v. I don't own a Bolt, but I've monitored my Prius. About 75% efficient L1 charging the Prius. I'm told L2 is about 85% efficient in the Prius. Curious how the Bolt does.
 

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I have a 240 V Charge Point EVSE and the energy usage shows up on my iPhone App. It is usually very close to the energy used since the last full charge. About 5% higher I think.
 

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Ditto. Just for fun for each charging session I flip the stats over to an excel sheet. I also manually calculate the cost per kwh (lowest rate, which I always charge at) from Toronto Hydro’s rate schedule & can attest that Chargepoint’s cost data is bang-on.

As of this month for my first 7,000 kms (4,350 miles) my total hydro cost was $129.13 CAD in adding a total of 1,163.2 kWh’s.

My wife’s ICE – CUV averages around 9L/100 km. (26 mpUSg). With local fuel prices averaging around $1.10/litre ($4.15 per USgallon) during the same time period. Fuel cost to go the same 7,000 kms in her ICE is about $693.

So my fuel cost was 18.6% of my wife’s fuel cost. I expect that will swing less in my favour during the winter months.
 

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Anyone else compare the wall supplied kWh to what the Bolt reports as having received?

I have a 240 V Charge Point EVSE and the energy usage shows up on my iPhone App. It is usually very close to the energy used since the last full charge. About 5% higher I think.
So are you saying the electric supply from the wall is about 5% higher than the amount stored in the Bolt's battery? About 95% charge efficiency? That is extremely good.

The main thing reducing charging efficiency on the Prius appears to be the fan motor and electrical contactor which both operate during charging. Since charging takes twice as long on L1, about twice the amount of energy is wasted running these systems, which reduces charge efficiency to 77%.

Ditto. Just for fun for each charging session I flip the stats over to an excel sheet. I also manually calculate the cost per kwh (lowest rate, which I always charge at) from Toronto Hydro’s rate schedule & can attest that Chargepoint’s cost data is bang-on.

As of this month for my first 7,000 kms (4,350 miles) my total hydro cost was $129.13 CAD in adding a total of 1,163.2 kWh’s.

My wife’s ICE – CUV averages around 9L/100 km. (26 mpUSg). With local fuel prices averaging around $1.10/litre ($4.15 per USgallon) during the same time period. Fuel cost to go the same 7,000 kms in her ICE is about $693.

So my fuel cost was 18.6% of my wife’s fuel cost. I expect that will swing less in my favour during the winter months.
What is your supplied KwH to delivered KwH ratio? Just curious what charge efficiency you're seeing.
 

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Charging loss is likely around 7.3%

... the electric supply from the wall is about 5% higher than the amount stored in the Bolt's battery? About 95% charge efficiency? That is extremely good.
My Bolt EV measurements show a charging loss of about 7.3%. It is a bit variable, but I seldom see 5%. I am gradually compiling a history which I will share at some point.
 

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I have monitored every charge and recorded the KWhrs Used to charge. The Oem Charger seems to be about 85% efficient at 12 Amps. My Juice Box is showing 87% and 93% at 120v 12amps & 240v 20Amps respectively. Over 574KW I have averaged 87.4% effieciency to date.
David b
 

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Charging loss is likely around 7.3%

What kWh charge rate are you running? I would expect higher efficiencies at higher charge rates.
This is a level 2 charger that I have discussed elsewhere on this site. It charges at 32A and about 230 volts. I measure the charging efficiency by looking at how many kWh the car used, reported by the car, and how much power was used to replace it, reported by my charger, which is a ChargePoint home charger. There are other ways of measuring efficiency, I am sure. I do not claim my numbers are the best way of measuring charging loss, but they do say the energy put into the car is more than the energy used by the car, which I interpret as charging loss. It is averaging about 7.3% so far.
 

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Anyone else compare the wall supplied kWh to what the Bolt reports as having received?

So are you saying the electric supply from the wall is about 5% higher than the amount stored in the Bolt's battery? About 95% charge efficiency? That is extremely good.

The main thing reducing charging efficiency on the Prius appears to be the fan motor and electrical contactor which both operate during charging. Since charging takes twice as long on L1, about twice the amount of energy is wasted running these systems, which reduces charge efficiency to 77%.

What is your supplied KwH to delivered KwH ratio? Just curious what charge efficiency you're seeing.
For my last charge I'm getting 94% or 96% efficiency. Don't know which of those two numbers is the right one. As I don't know if the tail on my EVSE graph (pic below) is due to battery conditioning or not. That is, if my EVSE report includes battery conditioning usage I don't think I should include that batt cond usage in comparing EVSE kWh's versus Bolt Energy Detail screen kWh's.

In any case I'm quite pleased with the 94%+ efficiency.
 

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That Eyedro looks interesting. Do you know if it can be hooked up to just the dedicated 220V breaker I have feeding my charger? Any experience with these?
 

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That Eyedro looks interesting. Do you know if it can be hooked up to just the dedicated 220V breaker I have feeding my charger? Any experience with these?
I use a Sense monitor (basically the same idea as an Eyedro – a network connected monitor device that detects throughput along the mains), and you'd connect it to a 120V breaker and the common ground. These sensors detect patterns by device and break out the usage from your EVSE as distinct from other appliances.
 

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Sense monitor

I use a Sense monitor (basically the same idea as an Eyedro – a network connected monitor device that detects throughput along the mains), and you'd connect it to a 120V breaker and the common ground. These sensors detect patterns by device and break out the usage from your EVSE as distinct from other appliances.
Did "Sense" detect your Bolt EV? I have had my Sense for nearly a year now, and it still has not found by Bolt EV.
 

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I use TED Residential (The Energy Detective) to monitor my critical home circuits, including both legs of the Bolt's 240V charger. It lets me view/export data down to the second. In my previous house I used the "Web Energy Logger". It was slightly more expensive, but was much better with many input options including On/Off and temp sensors.

I have found the Bolt to be between 82-84% efficient with the 120V/12A standard travel charger. When I use L2 240V/12A charging I get 85-87% charge efficiency. Clearly L1 charging is about 3% less efficient than L2 charging. I also noticed (as expected) that charging the battery to full verses a hilltop charge will be less efficient. When charging the battery above 90% more charge power goes towards internal battery heating as wasted heat loss.

Charging efficiency dips a couple % when cold because the car uses power from the plug to heat the battery to about 40F when plugged in. As an experiment I have left the car outside at 0F to L1 charge. Charge efficiency was 55%, which let me calculate that on average 1/3rd of the 1440W grid power (480 Watts) was used for battery heating during charging.
 

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We use this system--The Energy Detective, that monitors every panel and most of the circuit breakers on our property. The 240V 50A circuit that powers the L2 charger for our Volt/Bolt fleet records real time and accumulated kW and kWh for these. It's pretty slick, and not much beyond average DYI skill!

Here's a shot of one of the displays from the app that goes with TED.
 

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Has anyone ever measured the power factor of the on board charger? When I hooked up a current transformer to my home metering system, I only put a CT on one leg of 220v... so I had to multiply by 2 to get 220v power... ok.... but I later had to change that to 2.67 so that the power shown used on my meter matched the power the car said it needed to fill up. So I’m guessing the power factor is 0.7 or so? Anyone confirm this? Naturally the way to correct this is putting a capacitor in line with the charger to counteract the inductive lag in PF.
 
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