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> Noisy and fuel-inefficient (9 mpg), the Grummans are costly to maintain.

> Environmentalists were outraged when DeJoy announced that 90% of the next-gen vehicles in the first order would be gas-powered.

I was gonna say they environmentalists were wrong for this, if the new trucks get significantly better mpg performance that's still a big win.

But apparently with the AC running the new trucks still only get 9mpg.[1][2]

[1] https://earthjustice.org/press/2022/message-delivered-usps-c.... [2] https://arstechnica.com/cars/2022/02/the-epa-and-white-house...

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Here is the original environmental impact study from USPS - https://uspsngdveis.com/documents/USPS%20NGDV%20Draft%20EIS....

"14.7 miles per gallon (mpg) (without air conditioning) 8.6 mpg (with air conditioning)"

The same document estimates off the shelf commercial right hand drive vehicles averaging 6.3 mpg if used fleet-wide.

Same MPG but now with AC is a huge win!

I'd like to see the ratio of hours with AC on vs off fleet-wide after the first year.

From a 2019 IEA report: "Estimates from the literature reveal that around 6% of the annual global energy consumed by cars is used for MAC(mobile air conditioning), varying by country between about 3% and 20% depending on climate, driving patterns and traffic congestion. It can peak at over 40% in warm climates and congested traffic. This equates to around 1.2 Mboe/d consumed by MAC units in cars alone, with other road vehicles adding another 0.6 Mboe/d. For electric vehicles, MAC can reduce driving range by up to 50% on hot and humid days."

https://www.iea.org/reports/cooling-on-the-move

> "14.7 miles per gallon (mpg) (without air conditioning) 8.6 mpg (with air conditioning)"

Both of those are absolutely embarrassing, did they use a 1950s Soviet tank engine? According to a quick Google search, a Ford Transit (bigger sized but not optimised for post delivery van) gets 33-46 mpg depending on the engine.

Yeah, a post vehicle will start/stop much more, but that's where start/stop tech, and maybe even hybrid come in.

An open door will kill your mileage. USPS vans are designed for an incredibly specific role.

> Environmentalists were outraged when DeJoy announced that 90% of the next-gen vehicles in the first order would be gas-powered.

As they should be. Most of my family are mail carriers and as a kid I rode with them a few times for the day. Electric Vehicles would have been perfect for this work, but DeJoy probably was lobbied (in Europe that is called bribed) and bowed to the fossil fuel industry.

This is from someone who believes EVs are only really viable for local errand running (right now).

Even ignoring lobbying, it's his party's (and the president at the time's) very outspoken position that EVs are some green nut's pipe dream being shoved down their throats.

It likely would have been extremely bad for him personally politically to do what ended up happening on his own, as opposed to after pressure from congress and lawsuits.

How can you possibly believe that? The first weekend I had my model 3 I drove it across two states, since that's where I bought it. It's got every bit of utility my previous ICE car had.

> Oshkosh's proposed vehicle will only average 8.6 mpg (27.35 L/100 km) according to the EPA, a barely noticeable improvement on the current Grumman-made LLV trucks, which average 8.2 mpg (28.68 L/100 km).

Such a wasted opportunity

It’s a really hard task to make an efficient gas vehicle that stops and starts constantly. They’re just really bad at it.

Sure you can make it a full hybrid but then you’re like 80% of the way there to a battery vehicle anyway.

Also note that while the new one isn’t that much better it is providing air-conditioning. And the whole truck looks bigger so I suspect it weighs more. So the engine is doing more work than in the LLV.

>Sure you can make it a full hybrid but then you’re like 80% of the way there to a battery vehicle anyway.

This sounds like a good thing? Currently the most expensive component of electric vehicles are their batteries, so hybrids seem optimal. Hybrids excel at the exact use cases mail trucks have, so it seems a bit baffling they didn't go with that form of electrification.

Toyota has proven maintenance and reliability aren't an issue with hybrid tech.

Full hybrid has the downsides of electric (electric stuff to be serviced and weight/costs associated) and the downsides of gas (emissions, complexity of maintenance + engine, weight/cost of engine).

These are government fleet vehicles being used for lots of miles every day. They're going to use these for 20+ years. If the up front cost is a little higher but it has a big payoff, it's totally worth it.

The calculus is different from an individual's car. I still don't think it's worth it there now that electric has gotten so much cheaper, but that's a personal decision.

> Hybrids excel at the exact use cases mail trucks have

Compared to gas, yes. But the thing is electric cards excel even more.

> Toyota has proven maintenance and reliability aren't an issue with hybrid tech.

They proved it works reliably. But it's still far more complicated than an EV drivetrain with WAY WAY more high tolerance parts that wear. It's never going to be cheaper in maintenance.

1: The cost of the gas engine is offset by the reduction in cost and weight of a smaller hybrid battery.

2: Hybrid buses are already a thing, and they're subject to even more usage and wear, and work very reliably.

3: Cheaper maintenance as an absolute number isn't the goal, but a reduction in total cost of ownership. Remember there's a bunch of gas that's not being used or paid for. The lower the starting MPG, the higher the benefits electrification brings.

Sure you can make it a full hybrid but then you’re like 80% of the way there to a battery vehicle anyway.

But then you don't need to build dozens of charging ports at post offices that may or may not have the electrical infrastructure to charge a fleet of mail trucks every night

It's a fleet vehicle. The government can afford it and it will pay off in spades over the lifetime of the vehicles.

Upfront cost doesn't matter nearly as much as lifetime cost. And the difference is not going to be small.

Wasted opportunity for what?

> In December 2022, USPS announced that 75% of its initial order of 60,000 NGDVs would be BEVs. By 2026, all new NGDVs ordered will be delivered as BEVs.

So the should be very few of these ICE variants around presumably primarily in areas where the charging capacity is impractical to install. I don’t know how 8.6 mpg fares against similar trucks to know whether better ICE alternatives were possible and hybrid would likely add significant weight, cost and maintenance for likely little comparative value.

> in areas where the charging capacity is impractical

Educate me: why would charging capacity be impractical anywhere? They would build and use their own chargers.

Are there places that have weak grid power?

Chargers cost $$ to deploy and there may not be a sufficient amount of customers and trucks to warrant that money (+ may not have easy maintenance for BEVs in those places). That could be one explanation. And yes, there are probably a lot of places where the power grid wouldn't be rated to charge up truck batteries and need updates of infrastructure such as transformers to deliver that amount of electricity to the postal depot.

I'm not informed on the matter but those would be my best guesses.

Repairs (not maintenance per say) might be something.

I'm not convinced the chargers would be a problem, considering home chargers cost a couple thousand to install. As for infrastructure: can the building run a clothes dryer? Then it can probably charge an EV.

For repairs I'm sure the current LLVs have their own challenges. There's a good chance you can't find LLV parts in rural areas either. (Maybe they just swap them out and do repairs at the home base?) So EVs are not much different in that regard.

> considering home chargers cost a couple thousand to install

Home chargers, unless your neighborhood and/or home has special infrastructure to deliver more power, are limited to 120V. You have to remember that these are huge trucks with huge batteries and it’s not immediately obvious they can deal with trickle charging. And you’re not charging just 1 vehicle at a time but basically charging your entire fleet and you need this to be reliable 24/7. The logistics and costs of that are entirely different from a home charger.

> As for infrastructure: can the building run a clothes dryer? Then it can probably charge an EV.

again - your mental model is wrong. As you scale up your challenges are different and charging a fleet of vehicles. It’s not a laundry service so it may not have been provisioned for that many clothes dryers running at once and need substantial renovations. And you may want chargers that pull a heck of a lot more than a dryer because you need this to charge more quickly. Think about a fast charging station - it’s energy requirements are not at all the same and that’s why often at places you only see one or two (partially cost / demand for them but also being able to supply that energy is a real thing). Think of it this way - normal outlet is at 1.4 KW which is slow for a car and who knows how long for a truck battery. Faster chargers range from 3.7 kWh to 350kw and multiple that by the number of vehicles you need to charge simultaneously. It’s not necessarily the straightforward problem you think it is

> For repairs I'm sure the current LLVs have their own challenges. There's a good chance you can't find LLV parts in rural areas either.

The supply chain and knowledge base for ICE vehicles is far more established in rural areas. And usually you’re trying not to ship vehicles around for repairs but repair them locally instead. In theory BEV requires less maintenance and lasts longer so things could balance out but who knows since BEV trucks are pretty rare and this is the first of its kind design from a company not necessarily known for their BEV expertise.

I can’t quickly find the mileage with the AC not running. More to the point, it is mostly a myth that running the AC uses a significant amount of fuel. The compressor is usually driven by the serpentine belt, and adding the clutch plate for the AC into that system does not add significant drag. A little, yes.

It can have some added effects for more modern vehicles. For example, if the AC is running in my car, the engine auto start/stop is disabled.

I would assume it's not the clutch plate that adds significant drag, but the AC compressor itself.

Yeah I could have phrased that better. The clutch plate engaging the compressor would have been more specific, I assumed it was implied. Apologies.

> it is mostly a myth that running the AC uses a significant amount of fuel

What?

Modern car AC compressors use about 1 HP (.7kW) of power, with a duty cycle highly dependent on temperature but if you break the seal periodically, like by opening the window to put mail in a box, it will be running 100% of the time even on an 80 degree day. For a hatchback at 70mph that's up to 10% of your energy usage. It's much harder to quantify for stop and go traffic because you have a bimodal situation of either zero HP generation or like 50 HP to accelerate in slow city traffic, but all ICE vehicles use more energy (have less economy) in city driving than highway driving, so on average it's using a higher percentage of your energy consumption in city driving.

So turning on the AC on a hot day will reduce your economy car's mileage from 33 to 30, your truck's mileage from 12 to 10.8, and your Prius from 48 to 44 and worse for city driving. The numbers they claim in the above studies suggest they are using a higher capacity compressor to deal with the air volume constantly being opened to the outside.

What do you mean “what?”

You ignored a word: significant

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