Reported Trip Energy Used vs Energy required to recharge car

[Eric4539]

I checked MFM, and I cannot figure out how to Delete the incorrect address.  I go to Value Charge Profiles>Create a Value Charge Profile, it shows a wrong address in My Charge Locations.  The address showing doesn't even exist, and I cannot change it or delete it.  But it is the correct city and zip code.  I have to name it in order to proceed.

 

Am I in the wrong place to Edit, Delete or Add an address or charging location?  Thanks!!

[murphy]

Do it in the car.

While parked at home create a point and give it the name Home.

[larryh]

In MFM, select view all under value charge profiles and then my charge locations.  Click on the circled x on the location to delete.

Edited July 31, 2013 at 09:03 AM by larryh

[Eric4539]

I tried setting this in my car and I could not create a Home or Default charge location.   I tried MFM but it does not give me the option to delete.  I go to View all but it doesn't allow me to do a thing.  No circled red X.  Could not possibly be user error could it???  :)

[larryh]

There are three tabs at the top after selecting view all:  Value Charge Profiles, My Charge Locations, and My GO Times.    Select My Charge Locations and click the circled blue x to the right of the location to delete.

Edited July 31, 2013 at 08:48 PM by larryh

[larryh]

Note that the fuel consumption reported by the Trip Summary/Odometer seems to accurate and can be trusted.  It claimed for the 1170.1 miles that I used 11.35 gallons of gas.  When I filled the tank with gas, the nozzle shut off at about 11.2 gallons of gas.  I added a little more to bring the total to 11.35.

This time when I refueled, the car reported that I used 10.81 gallons of gas.  I actually put in 11.344.  The car underestimated the gas consumption by 5%. So it seems that the MPG reported by the car is not always accurate. 

Edited August 10, 2013 at 12:53 PM by larryh

[Griff]

This time when I refueled, the car reported that I used 10.81 gallons of gas.  I actually put in 11.344.  The car underestimated the gas consumption by 5%. So it seems that the MPG reported by the car is not always accurate. 

+1

I couldn't get more than 13 gallons in mine and it said I had used 13.25.

[dlb92]

Power supplies for computers have efficiency ratings.  Mine is 85% efficent but the low end ones can be around 60% efficient.

 

I'm assuming in the future chargers for EVs will need to have efficiency ratings.

 

I ordered the Clipper Creek LCS-25 L2 charger.  Anyone have any experience with this or an idea of how efficient these are?

[murphy]

The charger is in the car. 

 

The external box should not have been called a charger.  It delivers either 120 volts AC or 240 volts AC to the car.  It is nothing more than a sophisticated relay that the charger in the car can control to turn the power on and off.

 

There is a specification for a different style plug that would deliver high voltage DC to the car for faster charging.  It has not been implemented so far in Ford vehicles.

Edited August 11, 2013 at 12:55 PM by murphy

[dlb92]

That's what I gathered after reading some more.

 

Larryh posted a graph with a 120V, anyone care to post a graph/results using the 240V?

[murphy]

That's what I gathered after reading some more.

 

Larryh posted a graph with a 120V, anyone care to post a graph/results using the 240V?

Here is a graph of wall power during charging of my car.

 

http://www.fordfusionenergiforum.com/topic/740-graph-of-charging-a-completely-depleted-battery/?do=findComment&comment=3098

[dlb92]

So I had to use some gas today and it seems if you are going on a long trip using gas and battery dividing by 1.4 is also low balling your real MPGe right?

[larryh]

To compute MPGe correctly when you have used gas, you can't just divide the MPGe by 1.4.  You need to determine the plug-in energy used and multiply only that by 1.4.  You don't want to multiply the gas consumed by 1.4.  The car measures gas consumption relatively accurately. 

 

So if MPGe was 63 MPGe and you drove 56.5 miles, you have 0.897 gallons equivalent of energy.  If you consumed 0.7 gallons of gas, then the gallons equivalent of electricity is 0.897 - 0.7 = 0.197.  So the correct MPGe is then 56.5 / (1.4*0.197 + 0.7) = 58 MPGe.

[dlb92]

So I drove 19.9 miles, it shows 87 MPGe and I used 0.1 gallons of gas.

 

19.9/87 = .229 gallons of equivalent energy

 

0.229 - 0.1 = .129

 

19.9 / (1.4*0.129 + 0.1) = 71 MPGe

 

That's some pretty neat math there..took me a second to figure out how you did that.

[http]

It was my understanding that there would be no math.

 

[bwehry]

The following is an updated chart showing the actual kWh consumed by the car as measured with a Kill A Watt electricity meter connected to the wall outlet vs the kWh of Energy Use (the amount of plug-in energy the car claims was consumed) as displayed on the car's Trip Summary/Odometer console display.  I am using the 120 volt charger that came with the car.  Also, I am now using the "Charge Now" setting to charge the car and not the "Value Charge" setting.  There is now a lot less variation in the data.  Any remaining variation is now probably due to round off error.  The reported kWh on the car's display console shows values only to one decimal point.

 

 

 

I start with a fully charged battery in the morning.  At the end of the day, I record the kWh of Energy Use displayed on the console using a trip odometer.  I then recharge the battery and measure how much electricity was required using a Kill A Watt meter.  The car is allowed to sit overnight until I take the next trip the following day.  This is the correct procedure to measure MPGe.

 

As illustrated in the chart, the actual energy consumed by the car is 1.4 times what the car reports.  So if the car displays an energy use of 5 kWh, the amount of electricity consumed by the charger to charge the battery for that trip was 5 * 1.4 = 7.0 kWh.

 

This implies that for a trip entirely in EV mode, the true MPGe for the trip is the value reported by the car divided by 1.4.  So if the car reports 140 MPGe, the true MPGe is 140/1.4 = 100 MPGe.  I am adjusting the values that I enter into Fuelly to account for actual kWh consumed from the power company to charge the car.  The true MPGe readings are lower that what is reported by the car.  So for the last 1170.1 miles since I previously refilled the fuel tank, the car reported 70.8 MPGe.  Using the 1.4 adjustment factor, I compute the actual MPGe to be 63.4. (Note you can't simply divide by 1.4 in this case because gas and electricity were both consumed.)

 

Note that the fuel consumption reported by the Trip Summary/Odometer seems to accurate and can be trusted.  It claimed for the 1170.1 miles that I used 11.35 gallons of gas.  When I filled the tank with gas, the nozzle shut off at about 11.2 gallons of gas.  I added a little more to bring the total to 11.35.

Larryh - you certainly have done your homework!  All this math is making my head numb just glossing it over.  Quickly reading thru the posts I do not see where you included Regen in the calculations.  I assume the MPGe displayed on the dash includes Regen.  However, the kW-h to charge the battery does not include the Regen.  Therefore, if you include Regen in your calculations and add that amount to your calculated "true MPGe" does that get closer to what is reported from the car and account for most of the 1.4 larryh factor? 

[larryh]

During regen, the plug-in energy displayed on the car's console decreases and the MPGe that it displays increases (and, of course, it takes less plug-in energy to recharge the car which will be observed on the Kill-A-Watt meter).  So the charts shown do take regen into account.  I have been continuing to update the plot above.  The factor is currently 1.3899.

Edited August 24, 2013 at 10:35 AM by larryh

[larryh]

After two weeks of charging with the 240 V charger, I have computed the ratio of actual kWh consumed at the wall outlet to the plug-in energy consumed reported on the car's console as 1.23.  For the 120 V charger it is 1.39.  The 240 V charger is definitely more efficient in charging the battery vs . the 120 V charger. 

 

72% of the wall outlet energy is used to propel the car with the 120 V charger.   81.5% of the wall outlet energy is used to propel the car with the 240 V charger.

 

It takes up to 5.9 * 1.23 = 7.3 kWh to charge a depleted battery with the 240 V charger.  It takes up to 5.9 * 1.39 = 8.2 kWh for the 120 V charger. 

Edited September 19, 2013 at 11:05 PM by larryh

[larryh]

Below is a graph showing the power consumed to charge a fully depleted battery.  The console indicated 5.8 kWh of energy was used.  The actual amount of electricity required to charge the car was 7.071 kWh.  It took 2 hours and 9 minutes. So in this case the ratio of kWh consumed at the wall outlet to the plug-in energy consumed reported by the car was 1.22.

 

 

Edited September 24, 2013 at 09:28 AM by larryh

[larryh]

Below is a plot similar to what I did with the 120 Volt Charger.  It shows the amount of electricity required to charge the battery with a 240 Volt Charger versus the reported Plug-In energy consumed reported on the car's console.  It takes 1.225 times more energy to charge the battery than what is actually extracted from the battery and used to propel the vehicle as reported on the car's console.  In other words, only 1/1.225 = 82% of the energy used to charge the car actually propels the vehicle.   The remaining 18% of the energy is lost mostly as heat.  For the 120 V charger, the numbers are 1.3888 times more energy and 72% efficiency, i.e. significantly less efficient.  

 

Over the last couple of months, my true MPGe for trips entirely in EV mode (not what is reported on the car's console) is 124 MPGe based on charging with the 240 V Charger.  It is 109 MPGe based on charging with the 120 V charger.  Just by using a 240 Volt charger vs a 120 Volt charger, true MPGe increases by 14%.  True MPGe is measured using the actual electricity consumed from the wall outlet. 

 

 

Edited October 4, 2013 at 03:01 PM by larryh

[ChuckJ]

For me (and I suspect many others) the 220 is a must!  Thanks for the efficiency calculations guys!

 

ChuckJ