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KaiserPro

From the headline I was assuming it was a tiny 20kw job.

But it being a 1.9mw(thermal) makes sense.

I wonder what the support requirements are, like how do you yeet the heat to make it efficient?

Also containing super heated helium seems hard for any length of time. I wonder what the operating lifespan is.

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Meet EMD DDA40X [1], the most powerful diesel–electric locomotive model ever built on a single frame incorporating two diesel engines with an effective power output of 4920 kW. Given the expected losses in the diesel engines (~40-45% effective, 60-55% waste mostly in the form of heat) and diesel-electric traction system (power generation, traction motors, gearing etc, around 80% effective) which gives a total system efficiency of around 35%. Assuming most of the waste energy ends up as waste heat this ~30m long locomotive (a bit more than two 40ft containers) needs to shed around 9 MW of waste heat or about 4 MW per 40ft standard container length.

[1] https://en.wikipedia.org/wiki/EMD_DDA40X

They say it needs to be refueled after 5 years and that it can be done 4 times for a total lifespan of 20 years.

1.9 MWt still seems like a huge amount of energy/heat for something that fits on a truck and is supposedly air-cooled (they claim no water is required).

Where does all that heat go?! They must have some very impressive fans.

Yes, that's crazy. They say up to 1 MW electric which would mean (33% efficiency) 2 MW of heat to get rid of with air cooling. Later they mention facility heating which sounds more realistic, I guess?

I mean its not that much different from a diesel generator, they are around 30% efficient, so they'd also be kicking out the same amount of heat?

https://www.generatorsindustrial.com/products/1mw-diesel-gen... has a simple radiator.

but then the heat profile is different I suppose, and the efficiency doesn't depend on being able to shed heat.

Heat transfer has the lovely property of scaling nonlinearly by temperature difference. You need a lot of big fans to cool your CPU from 75C on the die to a 25C room, instead of a 50C difference these reactors will dump heat at hundreds of degrees C warmer than the local environment.

They say five years before refueling and 20 years total lifetime.

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