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Comment by jfengel | Hacker News Reader

That's interesting, since electric vehicles should be cheaper in the long run -- especially if they can arrange lower prices for overnight charging.

Perhaps the up-front costs of an electric vehicle are prohibitive for their constrained financial situation. If so, that is an unfortunate bind, if it causes more financial costs in the long run.

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> since electric vehicles should be cheaper in the long run

Do you have a reference for this? I'm curious to see where the costs went. For someone like USPS, who purchases mostly one model, in bulk, with long term maintenance as part of the plan, the math might be a little different.

My numbers may be a bit out of date, but I feel are still somewhat in the ballpark.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.

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.

> 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%.

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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