MrGadget said:
... about 50 miles round trip daily... So, my questions would be: Is this reasonable to expect to be able to get 50 miles per day without worry? The commute would be 90% highway (65 to 70 mph speed limits, fairly open highway).
Also, how would the car handle our very cold winters?
Well, lets start with the basics. When new, the LEAF will go about 4 miles per kWh of stored energy at 65mph at sea level in 70F (or warmer) air on dry, level, no wind, hard surface roadways with NO heater or air conditioning.
The battery will hold 21kWh usable when new at 70F degrees or greater. Range autonomy is simply:
Stored energy multiplied by economy (rate of consumption)
21kWh * 4 miles per kWh = 84 miles of range autonomy
So, lets consider the first part of the equation; stored energy. If the battery is cooled, it will lose capacity at about 1% per 4F degrees below 70F, so that on a really cold day of -10F, that is 80F degrees below 70F. So, -10F would have 80 divided 4 equals 20% reduction in battery capacity, or:
21kWh - (21kWh * 20%) = 16.8kWh
In addition, as the battery ages, there will be further loss of capacity. In your environment, you won't have the huge losses associated with places like Phoenix, but there will be some. For simplicity, lets say 10% loss in the first 2 years, and 20% in 5 years. Again, this loss will be SUBSTANTIALLY more in a hot environment.
So, you total stored available battery capacity in 5 years is 16.8kWh, and on that -10F day, equals:
16.8kWh - (16.8kWh * 20%) = 13.44kWh available
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Now, with 13.44kWh available on that cold day in 5 years, lets figure your economy. Sailing down the highway at 65mph at 4 miles/kWh will be 53.76 miles of range autonomy. By the way, that's without a heater:
13.44kWh * 4 = 53.76 miles range autonomy
In order to complete your trip with some reserve, you will have to slow down, preheat the cabin (for comfort) and not use heat except for defrost.
Other things that will diminish economy, of course, are snow on the road, standing water, going up and down hills, wind, and weight of your cargo and passengers.
The heater can EASILY reduce your economy by 25%, making you 4 miles/kWh become 3:
13.44kWh * 3 = 40.32 miles range autonomy with the heater on.
If you slow way, way down, you could increase your economy back up to 4 miles.
Please check out the range chart in my signature line.