All | Astronomy | BMS | Backpacking | Batteries | Bikes | Bolt_EUV | Camping | Channel Islands NP 2021 | EV_Charging | EVs | Ecomarathon | Hiking Running | Home Network | SRJC Earth Day 2022 street mural | SRJCO | Solar | Sustainability | Teardrop | Yard | e-Bike | e-Golf | e-Mower | e-Stang | lunar eclipse 2022 | random | reunion | reunion_slides | reunion_videos | reunion_yearbook
e-Stang Cost of Ownership Estimate 20230923 Posted on September 23, 2023 15:32:43.
e-Stang Cost of Ownership Estimate
9/23/2023
Only comparing prototype battery amortization and charging costs spent to gasoline cost saved.
Calculations:
- Duration driving electric: July 2006 through September 2023, 17.2 years
- Car has been driven 55,759 miles electric, 3,242 miles per year, 8.9 miles per day
- Batteries cost $17,000 and were replaced under warranty in 2008 after some cells dropped below 80% capacity; cells are now ~60% capacity after 15 years
- Car gets ~2.8 mi/kWh DC and the charger is at least 90% efficient, so AC efficiency is about 2.52 mi/kWh
- Car has used about 22.127 MWh, about 48% of what our 1.8 kW solar array would have produced during that time had its performance not degraded down to ~40% of initial capacity over the past several years, either due to the inverter or wiring, probably not panels
- Assuming $.20/kWh it has cost about $4,425 to charge my car. That number is high since I have gotten many free charges at work, and early on at public chargers when there were incentives.
- Total cost of charging my car plus the cost of the batteries if they were worth $0 today is $21,425, or $.384 per mile.
- I used to get 21 MPG average, so I avoided using about 2,655 gallons of gas. Assuming the average cost of gas has been $4, I would have spent about $10,621 or about $.190 per mile.
- I have spent $10,804 more to drive electric than gas, $.193 more per mile. Gas prices would have had to been over $8 for me to break even.
- I expect to use these batteries until about 50% capacity or about 3 more years to a total of 20 years, so the charging cost at that point would be about $5,415, and including the batteries would be $22,145, $.397 per mile. Gas use avoided would be about $12,350. Gas would have still needed to average $8.34 to break even.
Conclusion:
- My next pack will probably be mass produced batteries that will probably cost less, and gas prices will probably be more, so I might break even on my next pack.
- The cost and value of reducing greenhouse gases is hard to calculate but very important and not included in this analysis.
- A smaller, lighter and more efficient vehicle would reduce overall cost and impact, like The Teardrop...
e-Stang_BMS_2_2_2023 charging Posted on February 04, 2023 00:08:14.
Download XLSX File
2nd_module_3_pix Posted on August 29, 2021 22:45:57.
Open Directory
e-Stang charging Posted on May 08, 2021 22:56:04.
Download XLSX File
2021-01-18 e-Stang range test Posted on January 18, 2021 20:16:08.
Drove 25.7 miles without charging. Yellow light wasn't stuck on yet, but it would come on with heavy acceleration on the flats in 70 degree weather so probably only had a few miles more before stuck on yellow, so less than 30 mile range but how much less I don't know.
6_6_2020 4_05_08 PM_finishing_charge Posted on July 11, 2020 14:56:53.
Download ZIP File
6_23_2020 6_08_22 PM_chg_after_bal Posted on July 11, 2020 14:56:41.
Download ZIP File
valence cell balancing Posted on June 23, 2020 08:45:17.
Valence cell balancing
6/21/2020
Module 1
start ~10:22 AM 2.5 amps ~3.37V/cell interbal on since others aren't charging, makes sense, takes 100 mA away from charge current
accessory battery started at 12.75V pulsing down to 12.53V - BMS measuring high voltage or sending the data?
11:22 .14 amps 3.61 to 3.64V
11:41 .01 amps 3.632 3.659 3.622 3.643
Module 2
start 11:44 2.95 amps 3.35V acc batt 12.68V
1:54 12.63V accy batt module 2 .01A 3.653 3.652 3.649 3.618
Module 3
start 3:14 2.9 amps 3.35V 12.68V acc batt
5:51 .17 amps 3.650 3.649 3.637 3.655
Module 4
start 5:56 acc batt 12.54V 2.68 amps 3.33V
8:57 .11 amps 3.651 3.651 3.620 3.653
Module 5
start 8:11 PM 12.22V acc batt 2.7A 3.34-3.35V
9:39 .01A 3.634 3.633 3.623 3.653
Module 6
start 9:41 PM 12.15V acc batt 3.32-3.34V 2.73A
11:14 .15 amps 3.633 3.725 3.541 3.572 >>> THIS IS A PROBLEM
Module 7
Start 5:32 AM acc batt 12.50V 2.78 amps 3.32-3.34
7:07 .33A 3.542 3.687 3.712 3.552 >>> THIS IS ALSO A PROBLEM
Module 8
Start 7:09 AM 12.24V acc batt 2.70 amps 3.33-3.34V
8:44 .01A 3.645 3.642 3.606 3.639
Module 9
start 9:00 PM acc batt 12.41V 2.98 amps 3.35V
10:58 .41 amps 3.581 3.597 3.670 3.612
Module 10
start 7:35 AM 6/22 2.84 amps 3.34 to 3.35V acc batt 12.92 after charge overnight
10:24 .01 amps 3.623 3.654 3.655 3.652
Module 11
start 10:27 acc batt 12.69V 2.83 amps 3.33V
6:14 PM .01 amps 3.617 3.652 3.652 3.648
Module 12
start 6:15 PM acc batt 12.32V 2.06 amps 3.32 to 3.34V
8:02 .22A 3.603 3.655 3.575 3.671
5_19_2020 10_16_28 PM AC Mustang First Drive Posted on May 23, 2020 07:22:09.
Download ZIP File
2019-03-24_e-Stang_charger_testing Posted on March 24, 2019 14:57:37.
Mustang 240V charging with dead fans
3/24/2019
Charger fans died second time. First was Papst IPC 1154 rated that only lasted 3 years, required charging at 7.5 amps on warm days because it would not cut back agressively enough and would cut off.
Second ones were Delta IPC 1155s that lasted 9.5 years.
Without fans in 56 degree weather inside the garage, after 10 minutes at max 20 battery amps or 8 MPH charge rate it got above 100C and throttled to 16 amps at 107C, 6.4 MPH.
Put a ~18" fan pointed down in the engine compartment and the temperature dropped to 105C and increased to 18A, 7.2 MPH. This might be an acceptable workaround if 120V is also available but it usually isn't. I might try powering the fan on the inverter.
Throttled to 14A or 5.6 MPH and it went to 100C, so the max recommended at 56F. This is pretty linear though so I thought I'd go down in current and see where the temperature stabilized.
12A gave 94C, 4.8 MPH
10A gave 82C, 4.0 MPH
8A gave 74C, 3.2 MPH
6A gave 64C, 2.4 MPH
120V charges at 5A or 2.0 MPH so probably below this.
So assuming linear shift:
56F ambient 14A max 5.6 MPH 70%
68F 12A 4.8 60%
90F 10A 4.0 50%
106F 8A 3.2 40%
It hasn't ever gotten hotter than this.
126F 6A 2.4 30%