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Comment by mattbrewsbytes | Hacker News Reader

Where are they going to charge them once a post office has a few? I thought I read somewhere that charging infrastructure is fine for a household but a fleet of 10+ EVs will need significantly more juice (technical term) and hardware to mitigate significant safety concerns.

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I believe the USPS has worst case requirements of 56 kWh per vehicle per day. That's assuming very low efficiency and very long route. Assuming they have 208V 3-phase 200A service then perhaps they charge at the equivalent of 1 vehicle completely each hour. 10 a night is no problem.

As a practical matter, most routes are not 70 miles, they're more like 25. And the truck probably gets better efficiency than 800 Wh/mi.

Also, they stop and go constantly, so I would imagine regenerative braking could do a lot of heavy lifting here.

Yep. I wouldn't be surprised at all to find that in real life HVAC accounts for half or more of the total consumption on a typical stop-n-go route.

and postal trucks don't even have HVAC. At least the ICE ones. They get a lowsy fan

I just had to Google to see whether or not they even had doors.

At least in SoCal they (almost?) always leave the door completely open and they wear shorts, clearly because they don't have A/C.

In GA, it's the same. They usually wear shorts too. It's hot and humid so I don't blame them!

Yeah that is a major perk of the new postal trucks both EV and ICE is that they will finally get Air conditioning and an adequate heating system. The LLV had no AC which led to many issues in hot climates, and the heater was not large enough to heat the cabin well with the window open all the time.

20A per is plenty sufficient for overnight. A house has 200A service, commercial sites usually more and/or 3-phase which supports 3x the vehicles per amperage.

There is no "significant safety concern" or special hardware needed for additional chargers.

I think there's a few assumptions here that apply to households, but not purpose built business vehicles.

1. They may not be typical chargers. Connecting multiple vehicles to the same source which can distribute the power based on time and need may be possible in this case.

2. If these are purpose built, we don't know if charging the vehicles even applies. Totally made up idea: batteries easy to replace get shipped off for charging off-site and cycled daily. (+ single on-site charger for emergencies)

3. You're not charging 10 EVs immediately - you have 10 EVs which need power at the beginning of the next business day.

These are good points. We already have residential chargers which coordinate to share power, so it's very likely that any business-grade charger will have similar capabilities.

I do think swapping batteries is unlikely, however. It adds a lot of complexity, and if the typical route is only 25 miles long then a battery swap is overkill.

True about swapping - it was a totally made up idea. The point was that at some scale you get to consider things you can't apply to homes or even parking lots.

USPS isn't the first to buy electric delivery vans.

Installing chargers at the depot is what many other large business with electric delivery vans has done. Some smaller businesses have their staff charge the vehicles at home, and pay them for the electric.

The answer is gonna be based more on how many miles does a USPS driver drive a day? Average mileage on an EV is about 100 mile for 25 kWh. A standard (lower end) home 100A breaker panel would do about 20kw, enough for 200 kWh overnight, or 800 miles. A commercial site will likely have more than 4x that with at least a 400A panel, 3200 miles.

Some searching brings up 24 miles a day as the average for a postal route. Even if you round up to 50 miles a day per vehicles, a 400A service will do more than 50 vehicles at night. It's not ideal for trucks between facilities, sure. But for neighborhood last mile delivery you wouldn't have that many vehicles per facility, or distance traveled, making it pretty ideal to start rolling out electric vehicles there.

First paragraph of the article:

> The service awarded contracts on Tuesday for 9,250 battery electric vehicles and for more than 14,000 charging stations.

Reading farther in the article:

  It also remains unclear where the vehicles and charging
  stations will be placed, as those details have yet to
  be finalized, the agency said.

So, to answer the GP's question, "Where are they going to charge them once a post office has a few?" Nobody knows.

They're provisioning more chargers than vehicles. The answer seems fairly clear. For now, if you get three EVs at your local post office, I'd expect roughly three chargers installed.

Would you mind quoting the source for that? The article says something else.

You want a source for "I'd expect"? MLA style?

Me. 1 Mar. 2023. Hacker News, comment #34991363.

No, for the part where you made an assertion of fact. "I'd expect" is your opinion, and you're entitled to that of course. I was asking you to quote where you got the source for "provisioning more chargers than vechicles."

> They're provisioning more chargers than vehicles.

It's literally the first paragraph in the article. Scroll up, I quoted it in my original comment too.

> The U.S. Postal Service's plans for a nationwide fleet of electric vehicles are getting closer to being realized. The service awarded contracts on Tuesday for 9,250 battery electric vehicles and for more than 14,000 charging stations.

If you read more of the article, you will see additional numbers.

  As such, a contract has also been awarded for the agency to acquire 9,250
  commercial-off-the-shelf internal combustion engine vehicles "to fill the
  urgent need for vehicles." In December, the agency said that 21,000 COTS
  vehicles will be purchased and are "expected to be battery electric,"
  but said that depends "on market availability and operational feasibility."

"They plan to buy more EVs" can (again, I expect) probably be safely read to include "and the requisite infrastructure to accompany them" eventually.

The question was , "Where are they going to charge them once a post office has a few?" So, I'm not sure why you are trying to correct my factual quotes to answer that question by posting your expectations as to the future hypothetical existence of chargers.

This argument is pointless

Logically, most of the chargers will be at post offices to accommodate the fleet. Completely negating the question asked.

Outside of the post offices, where will USPS set up additional chargers? That is the unknown right now, if they actually do set up any outside of post offices.

There is significant doubt they would set up chargers outside of post offices, considering they acquired 14k charging stations and have 30k+ offices in service.

Perhaps, like with most complex problems, there isn’t a “one size fits all” solution. I’m all for skepticism but this criticism is just lazy.

It's incredibly lazy to say my criticism was "just lazy" since I didn't post criticism but answered a question about the contents of the article.

No, you made an irrelevant and dismissive remark under the “guise” of an answer. Lazy.

No, the existence and locations of these chargers is not set. They may not even get purchased. The current planned rollout is for 75 locations. The absolute truth to "where these will get placed" is nobody yet knows. Nobody knows where, because nobody knows where the vehicles will get placed.

Many post offices have parking lots where the vehicles park overnight currently. Mail carriers don't take these vehicles home, they typically park on USPS property overnight. I suspect this is the top candidate location for many of these chargers.

https://thumbs.dreamstime.com/b/usps-mail-delivery-trucks-lo...

Statements like that don't really answer the question. Other reporting on this has said that 75 locations are currently getting build-outs for charging stations. [1] The actual question is where these will be built. Answering "the parking lot" isn't actually helpful to "where".

[1] https://thehill.com/policy/energy-environment/3879040-usps-t...

Er, what? "The parking lot" is a perfectly good and reasonable answer to that question.

Their post history suggests they are pedantic just to be pedantic.

Yes, they are not being built yet. Where else do you think they would go?

You are making too many assumptions about the arrival of chargers and BEV in the first place.

When looking where the chargers will go, the issue is that the cars aren't necessarily going to be purchased and delivered, either. So, it isn't clear where the chargers will go, if anywhere. Today, there is a small rollout of chargers planned, but that isn't enough to say that many post offices will have chargers.

For those reasons, "the parking lot" isn't a feasible answer compared to specifying which post offices or other information. And, the USPS has said they don't know where the chargers will go, possibly a location centralized between several post offices. After all the question was asked by that poster, so it's best to presume that actual information was desired not flippant answers like are in this thread.

Many post offices have full lots today, so purchasing more vehicles and retiring some will surely mean there will be even less room for chargers in the parking lot.

You are correct, we do not have an official answer directly from USPS. The article says they still need to review which routes will work best with BEVs.

However, it is highly likely that, for the local offices and route which they find to be suitable they will build chargers in the lots, because 1) others in this space have already done this and it works, and 2) the place where the vehicles are currently parked is the place where it makes the most sense to park the vehicles, logistically.

https://www.rivianownersforum.com/attachments/amazon-chargin...

Mail fleet work 8am-6pm they have 14 hours to charge they don't need to charge all at once in 1-2 hours

A standard service panel in a given building will struggle, but the “juice” is easily available from your standard neighborhood power lines.

So at the local level they will have to build some new infrastructure for the last few yards, but this isn’t really a big issue

I found this podcast episode about digital circuit breakers pretty interesting and is relevant to this:

https://www.volts.wtf/p/the-digital-circuit-breaker-and-why#...

I don't have any idea what USPS plans are here, though.

Many post offices are not in residential zoned buildings, generally when you're low density commercial a building is closer to a substation. Though I'm sure many mail distribution centers have had low density industrial connections for sorters.

The Tesla Supercharger at my local Meijer is a little 10 foot by 10 foot fenced area for the electrical equipment. Seems fine.

Like there's the fenced area and then the charging stations next to the adjacent parking spots.

This may already be possible. But if not the capitalist in me says that upgrading thousands of post offices and their associated grids will create a lot of jobs.

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