I got the data back on my first month using timed based charging from Mid America. I don't have the data on how much energy I used for the Tesla in June/July last year, but I know we used it a lot less.
2025
11.90¢ per kWh regardless of time of day
2026
Starting on June 1-Oct 1
Off-Peak (10 PM – 8 AM): 7.60¢ per kWh
Regular Hours (8 AM – 1 PM & 6 PM – 10 PM): 10.08¢ per kWh
On-Peak (1 PM – 6 PM): 21.98¢ per kWh
I made two big changes during this time. I moved car charging to start at 10:15pm. I also changed the thermostat so that it would cool down to 70 from 11:30a-1pm, and then not kick in unless it got above 77 until 6pm.
My billing cycle was a little jacked last year(new build/moving), so it only included 26 days.
2025
1,139 kWh=$144.31
2026
1,344 kWh=$144.60
"Even though you consumed
205 more kWh over a billing cycle that was 3 days longer, your actual electric cost only went up by
$0.29"
During this specific 29-day billing window, your log tracks
20 total charging sessions:
- Home Urbandale (AC): 18 sessions
- Tesla Supercharger Shelby (DC): 2 sessions (on June 25th)
Focusing strictly on your home utility impact, here is what your vehicle pulled from your panel:
- Total Home Energy Used: 274.71 kWh
- Total Self-Tracked Cost: $16.48 (calculated at your baseline app rate of ~$0.06/kWh)
EV Share of Bill: Your Tesla accounts for
20.4% of your total monthly electricity consumption
"If you had paid a flat
11.9 cents ($0.119) per kWh (your all-in flat rate from last summer), the cost for that same 274.71 kWh of charging would have been
$32.69.
By shifting to the Time-of-Use plan and automated overnight charging, your actual utility cost for that power was
$20.89, keeping an extra
$11.80 in your pocket for the month."
From those 18 home charging sessions, you gained a total of
1,105 miles of range.
Breaking that down with your actual utility cost of $20.89 for that specific electricity window, you were driving for just
1.89 cents per mile in fuel costs.
If I would have driven my Kia Telluride that gets 21mpg those 1,105 miles, and fuel costs $3.80, what would that have cost me?
Driving the Telluride for those 1,105 miles would have required roughly
52.62 gallons of regular unleaded, costing you
$199.95.
Comparing the two vehicles for that exact month of driving:
- Kia Telluride: $199.95
- Tesla Model Y (On Time-of-Use Plan): $20.89
PDF
You saved
$179.06 in fuel costs just by taking the Tesla and taking advantage of your overnight electricity rates.
Not gigantic savings by switching to TOU plan, but it seems positive overall.
Just realized that I need to adjust my charging to reflect the 7.6 rate, not 6.
Adjusting for the true "all-in" summer off-peak rate of 7.6 cents ($0.076) per kWh (which includes MidAmerican's base rate plus the fuel and energy riders) gives the corrected breakdown for your home charging during this billing cycle:
- Total Home Energy Used: 274.71 kWh
- TeslaMate Logged Cost (at 6¢): $16.48
- Adjusted True Cost (at 7.6¢): $20.88
- Correction Deficit: TeslaMate underreported your bill impact by $4.40.
Updated Comparison vs. the Telluride
Even with the adjustment to the true rate, the math still heavily favors the Model Y for that month's 1,105 miles:
- Kia Telluride Gas Cost: $199.95
- Tesla Model Y True Cost: $20.88
- Actual Net Savings: $179.07
Your cost per mile shifts slightly from 1.49¢ to 1.89¢ per mile, meaning you are still driving for under two pennies a mile.