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by derekp7 1572 days ago
My numbers may be a bit out of date, but I feel are still somewhat in the ballpark. A battery that gets you 300 miles on a charge (90 kWh?) can be charged 1500 times, and costs $20,000, so that is $13 of wear per charge, plus about $12 worth of electricity (probably more, just basing off battery capacity not counting charge / discharge losses). So that is $25 per 300 miles. A car that gets 30 miles/gallon will cost around $30 per 300 miles. So electric saves you ballpark about 16% in fueling costs.

I'm sure though that the battery packs will come down in price by the time they need replacing, on the other hand the charging costs may be higher due to thermal losses.
3 comments
stetrain 1572 days ago
The average rural USPS route is 45 miles. Non-rural routes are closer to 20 miles. Low average speed (lots of stop and go) means they would likely beat what we are used to for EV energy usage per mile.

A 30kWh battery could probably handle most use cases even accounting for range loss in cold weather.

Edit: Also the USPS estimates the new gas-powered trucks will get ~8 miles per gallon with the A/C on, and ~14 miles per gallon with it off.

That would make your estimate closer to $16 per 300mi for the EV and $64-$112 per 300mi for the gas truck.

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antisthenes 1571 days ago
> In actual use by the USPS, which includes extensive stop-and-go driving for residential delivery, average fuel economy is about 10 miles per US gallon (24 L/100 km).[10]

From: https://en.wikipedia.org/wiki/Grumman_LLV

30MPG is a pipe dream for these vehicles. Going electric would save a lot more than 16%.

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ryathal 1571 days ago
The charging infrastructure is the real killer, you need 1:1 charger to vehicle or some kind of smart charger that can plug into X vehicles and charge each up overnight. There's also the power draw requirements that will take, so it may not actually be able to install sufficient charging on existing sites. There's also the maintenance on the chargers, which is admittedly small. Switching to EV means for the same budget you get say 20% less vehicles (assuming same cost), just because you have to spin up the charging.
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