What data can I use from the Car status screen?

[jkendt1989]

I am currently making a spread sheet so I can track all my data and millage used on the Leaf. My question is what data can I use on the car to track different things? I get the basics on millage and all.

I know there was a screen that said average miles per KWH. Can I take that plus my electric rate to average how much a month I am spending on electric with how many miles I have driven? Thanks!

 

[swaltner]

That would be a good start without needing to do anything expensive. I have a spreadsheet that I track all expenses related to a vehicle to calculate my cost/mile for each of the vehicles that I have owned. When moving to the Leaf, I converted all the items related to fuel expenses from gals of gas to kWh of electricity.

You could track your electricity usage through the Carwings web site http://www.nissanusa.com/owners" onclick="window.open(this.href);return false;, but that wouldn't show you the charging inefficiencies. Inflate the numbers by something 15-25% (depending upon if you're using L2 or L1 charging) to get a better idea about how much actual electricity you are paying for.

I personally added a TED 5000 monitor http://www.theenergydetective.com/" onclick="window.open(this.href);return false; to directly measure the power that my EVSE "consumes". This logs the actual kWh that I'm using, which includes the charging inefficiencies and any other losses. I act like I "fill up" by recording the miles driven and kWh consumed on a monthly basis into my spreadsheet.

 

[jkendt1989]

I don't have crawling or anything like that.

Does anyone know how to do the calculations on average KWH, miles driven and your current electric rate?

 

[klapauzius]

I don't have crawling or anything like that.

Does anyone know how to do the calculations on average KWH, miles driven and your current electric rate?

Your cost would simply be

miles driven /average miles/kWH (either from the dash or the energy screen) * electric rate per kWH / charger efficiency

charger efficiency would be the amount of energy that the battery gets from the AC wall mounted charger divided by the energy the charger draws from the grid. This value has been discussed somewhere on the forum, but for brevity a rough estimate would be .85 to .9.

 

[jkendt1989]

I don't have crawling or anything like that.

Does anyone know how to do the calculations on average KWH, miles driven and your current electric rate?

Your cost would simply be

miles driven /average miles/kWH (either from the dash or the energy screen) * electric rate per kWH / charger efficiency

charger efficiency would be the amount of energy that the battery gets from the AC wall mounted charger divided by the energy the charger draws from the grid. This value has been discussed somewhere on the forum, but for brevity a rough estimate would be .85 to .9.

Cool! Thanks a ton!

 

[planet4ever]

charger efficiency would be the amount of energy that the battery gets from the AC wall mounted charger divided by the energy the charger draws from the grid. This value has been discussed somewhere on the forum, but for brevity a rough estimate would be .85 to .9.

Cool! Thanks a ton!

I'm not sure where klapauzius got 0.9. That is almost certainly too high. As swaltner said, we normally use 0.75 for L1 (i.e. 120v) charging and 0.85 for L2. If you have a 2013 LEAF with the so-called "6.6 kW" on-board charger and you have a 30A charging station running at 240v you might get 0.87, but I doubt if it could be any higher than that. However I haven't seen any actual measurements of that configuration.

The primary reason for the variability is that there is a charging overhead related to keeping the charger cool. The cost of that overhead depends on how long the charging session takes, so it isn't just proportional to the charge. Many public charging stations, for example, run at about 207v rather than 240v. That makes the charging time longer and the overhead higher as a percentage of the charge.

Ray

 

[klapauzius]

I 'm not sure where klapauzius got 0.9.

I guessed it. Hence the "rough estimate" qualifier.

 

[cwerdna]

If you have a 2013 LEAF with the so-called "6.6 kW" on-board charger and you have a 30A charging station running at 240v you might get 0.87, but I doubt if it could be any higher than that. However I haven't seen any actual measurements of that configuration.

FWIW, when at charge at my work's Chargepoint L2 EVSEs, the display on the EVSE says the car pulls (IIRC) 5.8xx or 5.9xx kW. I don't know if the supplied voltage is actually only 208 volts and not 240 as I have no means of measuring and the EVSE doesn't say. Supposedly, 208 volts is common in commercial buildings.

 

[jkendt1989]

I'm doing a 30 Amp 240 charger w a 3.3 on board charger for a 2013 Leaf. What should my number be? .80 or .85?

 

[klapauzius]

Since the error between your estimate and your true consumption and cost will be about 15% between a value of .8 and. 9, pick something in the middle, it wont make such a big difference anyway.