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Comment by TimTheTinker | Hacker News Reader

Diesel will be with us for a very long time yet, even if all diesel buses were to be swapped for electric.

-- Diesel locomotives (train engines) and many ships use diesel generators to power electric motors -- this setup is useful for applications where high torque is required at low RPMs (even down to 0 RPM)

-- Many grid support power plants use diesel generators (especially for emergency backup)

-- Diesel-powered trucks, tractors, and heavy equipment

-- Military vehicles

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The first place to phase it out of is densely populated areas, because of all the particulate matter pollution which is particularly bad for people's health:

https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5352477/

Friends comment is people constantly complain about maintenance trucks, because they have to run the diesel engine to power hydraulics.

Thats one beauty of a proper electric truck: you can operate all the power equipment off the electric.

Here we go again, putting people ahead of mother earth.

Ships not only use diesel for generators but for propulsion in general; many engines found in recreational mid and large motoryachts are basically truck diesel engines adapted for a harsher maritime environment. Volvo Penta, Detroits, Caterpillar are very popular. Marine diesel is taxed differently and is somewhat cheaper than truck diesel (and has a different color due to a different dye added; marine diesel is red, truck diesel is yellow). Diesel is also safer than gasoline in terms of accidental ignition and explosion since the ingnition temperature is much higher than gasoline. Diesel fuel flash points vary between 52 to 96C (126 to 205F)

>Diesel locomotives (train engines) and many ships use diesel generators to power electric motors -- this setup is useful for applications where high torque is required at low RPMs (even down to 0 RPM)

Few ships are diesel electric. It's inherently fairly inefficient compared to mechanical power transmission. Diesel electric is mostly used in locomotives and heavy mining equipment where a mechanical drive-train would be overly complex or inconvenient to package (imagine the drive-train for a freight locomotive) but the machine enough driving that hydraulics is too inefficient (whereas something like a mining shovel doesn't do much driving and the market).

>Diesel-powered trucks, tractors, and heavy equipment

For stuff that's small enough to transport on a semi and doesn't need to go highway speed it's really hard to beat hydraulics for low cost and low cost of ownership. A slightly more efficient drive-train doesn't really make it far up the important features list when you're gonna be pushing dirt and your maintenance schedule and how hard on equipment your employees are dominates your longer term cost of ownership. Indoor stuff will go more electric but it's been electric for awhile, it'll just get better/lighter.

>Military vehicles

Not gonna happen anytime soon except some specialty applications (small inshore subs come to mind, SDVs are already electric). Military stuff needs to stay light for a variety of reasons and the last thing they need are a bunch of volatile batteries that need to be protected (whereas a fuel tank of diesel can act like armor to some extent).

US tanks use turbine, not Diesel engines. More military could have used those, especially as infra-red signature of turbines is lower, but it is chicken and egg problem. The present market is small and for tanks a turbine initially developed for helicopters were adopted. For other vehicles entirely new development is necessary. And it is very costly.

> infra-red signature of turbines is lower

Can you provide a source for this? It has been my understanding that turbines had more of an infra-red signature due to the hot exhaust and high mass flow.

Exhaust from a Diesel has much brighter IR signature as it’s exhaust particles are black bodies that radiates and scatter IR very effectively. As turbine generate much cleaner exhaust of molecules that does not radiate much in IR on their own, it’s IR signature is lower despite higher temperature and more exhaust mass. This is a rare example when pollution is bad both for environment and military applications.

I do not have references. I learned it from a buddy whom I trust.

Thanks, that is interesting. Would a particulate filter reduce the signature significantly?

I believe most military vehicles in the US run on JP-8 (based on kerosene).

https://en.wikipedia.org/wiki/JP-8

At least in northern Europe, Diesel engines are critical to the agricultural industry. Considering some farmers are still using 40 year-old tractors around here, I doubt the Diesel engines will go away any time soon.

But one of the advantages of Diesel engines are that they aren't really that picky when it comes to fuel. I don't think the engines are going anywhere, but we're probably going to see more and more non-fossil Diesel alternatives being used in the future.

> train engines, tractors, and heavy equipment

Run the numbers noting that all these have much lower power to weight ratio's than buses and cars.

Numbers say diesel is more expensive on a total cost of ownership basis.

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