Thread: Tesla Model 3
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Old 09-24-2018, 08:28 PM   #574 (permalink)
ProDigit
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Quote:
Originally Posted by redpoint5 View Post
Your math is too conservative, especially for a FL climate. Cabin heating typically draws much more power than cooling, and the overall range is drastically reduced by cold temperatures. Heat is no problem for a car like the Bolt or Model 3.

Let's say you could only charge 10 hrs a day on a 15A circuit (you never specified your capacity, so I'll assume the lower one). 10hrs * 120v * 12A = 14.4 kWh. Using a very conservative estimate of 4 m/kWh, you would add 57.6 miles of range every night, for a deficit of 12.4 miles. Over 4 nights (Monday - Thursday night charging), you would accrue a deficit of 50 miles. A 240 mile range Bolt would still have 190 miles of range come Friday morning, which is nearly 80% of the full range.

What is preventing a 240v outlet from being installed? Isn't there one for the cloths dryer or range already?



Every utility is different, but in Oregon the rate is $0.10/kWh regardless of how much you use, and in Washington $0.08/kWh. Consider it $0.11/kWh due to 90% charging efficiency. Assuming no rate change due to extra consumption, your 70 mile commute would consume 17.5 kWh (little more due to charge inefficiency, but compensated by 10% increase in price) and at $0.11/kWh, would cost $1.93.

My Prius gets 50 MPG, and at a cost of $3/gallon, would cost $4.20 for the same trip. That's more than double the cost using one of the most efficient vehicles made.

EVs are too expensive as you mention, but they are the ideal vehicle for commutes of 70 miles, or even twice that distance if 240v charging is available.
I beg to differ again!
Cooling your car by 15 degrees, costs more energy, than heating it up by 15 degrees.
Once temperatures surpass 90F, AC systems become very inefficient.
And in cars like the Tesla, the battery pack and motors already offer heating for the car interior, by using the waste energy to heat the cabin.

What reduces range in cold climates is the batteries running not at their optimal temperature (below 75F), more so than the heater uses. (you could try this out, by comparing a 40F run raising cabin temperatures to 65F to a 60F run, raising internal temps to 85F. Your range will be longer at 60F than at 40F).
Also, many EV users, use seat heaters, rather than cabin heaters.
While seat coolers, don't exist.

Also, your math poses a lot of issues.
1- At first, you don't account for charging efficiency. It's usually at 90%, so a 64kW battery would take 70kW to charge. Fast charging reduces that efficiency by almost double, to 80kWh.

2- The cost of electricity usually rises once you fall in a higher threshold.
Here in FL, the cost for electricity is around 10ct/kWh. It would become 15ct/kWh if you surpass the 1000kWh/month quota.
I have a small home, in the winter it wouldn't be a problem, but in the summer, AC cost drive my average consumption in the 900kWh /month.
A car would certainly topple the 1000kWh threshold.



Many homes in the us have only single phase.
Dual/tri phase power isn't available everywhere.

And sometimes even single phase power outside of the home isn't possible; think New York, how will one charge his car when one is living on a tenth floor apartment with no EV accomodations in the parking lot (or no parking at all)?

Also the price of gasoline hardly ever has surpassed over $3/gal, only in 2015-2016. But gasoline here, has mostly been between $2.25-$2.79/gal for the past decade or two.

And like I mentioned before,
The AC drains too much power, that for my 12 hours per day charge, it won't keep up with my 70 mile run.
Unless I have a split weekend, or a day where I can leave the car charging 24 hours.
Not calculating if the breaker trips, power outage, or someone trying to be funny, by unplugging my car.

Last edited by ProDigit; 09-24-2018 at 08:34 PM..
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