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Comment by ashoeafoot | Hacker News Reader

How do energy intensive processes like aluminium smelters or window glass producers preven their machines from self destruction ?

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Can't answer for aluminium, but I can answer for window glass: One of our plants was threatened by massive flooding 2021, threatening the float glass oven (which doesn't float itself despite the name). It was closed off with insulation, turned off, and everyone hoped for the best and no steam explosion. In the end, only the cellars with the control equipment flooded and it could be gradually (as the control cabinets were checked and restarted) brought up again without loosing too much heat a day later.

In short: Heat Inertia of large molten bodies is massive with good insulation. If the time is too long tho, only dynamite will dismantle a solid chunk of material again.

Is the heater keeping the material liquid not enough to re-melt it again?

Its not an oven alone, its a kiln that smelts up the components for glass of the desired recipe, then purs the glass on a long (~half a km) basin of molten tin where it stretches and cools slowly, pushing the solidifying mass down the basin until the end. Re-Melting it is as far as i know not possible, as the melting is done before the pouring. You can melt the tin again, but not the glass.

I'm guessing that liquid glass gets into some spots/crevices that it cannot be remelted from using built-in heat sources.

Interesting! Does this mean that you could use intermittent energy sources, like solar power, to heat up the float glass oven during the day and it woul keep enough heat during the night so that it could keep running in the morning?

Float glass is a continuous process, so it runs 24/7 and too much product is recycled into the smelter at the start again (Funnily, glass waste is actually a scarce resource). Getting the process dialed in to emit the desired quality is a long winded thing as far as i know (not involved in the process myself). Also, the heating is done with gas (LNG/CNG/H2) and electric in combination.

Yes, in theory, but your process control would be terrible, thus your product would also be terrible. Unless you invent something very clever.

But that makes them superb heat battery, which is under used at the moment to store energy.

because of the Carnot cycle, no? it just doesn't make much sense to store energy as heat

A lot of energy is spent to heat things anyway.

It works also with cold/frozen stuff - you can even store snow over the summer if needed: https://www.slf.ch/en/snow/snow-sports/schnee-und-ressourcen...

How did you find that much insulation quickly and what kind was it?

The Insulation is in place all the time because the process is very energy intensive and the glass over the whole basin is supposed to cool evenly. Just the end is not closed off as the glass is ejected in a continuous endless stream[1].

https://www.blindex.com.br/-/media/blindex/site-content/xx-n...

In some cases they don't have any practical ability to.

The Texas winter storm resulted in a lot of scrap at semiconductor lines due to power loss. There are industries that are completely dependent on grid power. You can't generate enough on site to back up 100% of your operation. Think about how much power one EUV source consumes.

The only reason Samsung is building additional factories in Texas is because the local utilities are effectively treating them as a critical load. The new plants are right by the ERCOT operation center and likely have access to the same cranking paths that the grid uses for black starts.

I have no idea how much power an EUV source consumes, but I’m surprised to hear that it’s more than a handful of kW. What’s the right ballpark?

ASML says 1.3 MW for a single system. So off by three orders of magnitude.

https://www.asml.com/en/news/stories/2024/a-sustainability-m...

Thanks for sharing the link! 1.3MW really isn’t that high of a load though. Thats a very straightforward load to be able to support via diesel generators. As an example, a typical large datacenter uses an order of magnitude more power, yet stays online following a grid outage.

This is the power consumed by the light source for one photo tool on one line.

There are thousands of tools. Material handling robots, compressors, HVAC, pumps, an entire data center within the factory, etc.

From source article…

> For example, a lot of that 1.3 MW went into cooling the system and handling the hydrogen flow used to prevent contamination build up.

> This is the power consumed by the light source for one photo tool on one line.

Actually, it’s not if you read the linked article. Try harder with your indignant reply next time to an entirely factual post. Sheesh!

Further, here’s a >one hundred megawatt generator installation (yes, used, but it’s always call for quote otherwise online) for a small fraction of the price of the EUV machine in case I need to further prove my point.

https://www.uspeglobal.com/listings/1705462-used-100-mw-2004...

There’s also multiple GE LMS100 generators installed in Texas and they each provide ~115MW of power. So not unprecedented for installation in the state either!

It's 1743 horsepower.

Yep, you did the simple math. 2MW generators are rather common place, they even come in portable (as in on a trailer) form.

>They require up to 10.2 gigawatt hours per tool annually

First hit off google.

Assuming they run them 24/7 that amounts to a power usage a bit over 1 megawatt, but they could be pulsed for all I know and use quite a bit more

Power guarantees and insurance.

They are also frequently situated close to reliable power sources such as nuclear or hydro, usually fed by more than one generating station.

A friend of mine lived close to a brick plant his power NEVER went out.

Anecdotal example: The, now closed, Aluminium plant here was build only because the government build a nuclear plant, which is still going. There was a coal plant next to it (closed now) as a backup for when nuclear was not available. Funny thing is most people thought the coal plant was the nuclear plant when driving by since it looks more like a plant, the nuclear dome structure is kind of hidden from the road and since natural water is used as cooling no big towers are close by.

I had the same experience living near a hospital. The whole city has gone out a few times, and our grid was either still up, or is one of the first grids back up.

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