Absolutely it's a strange choice. From a power perspective it can make sense since solar works very well, but from a water perspective it's a very strange choice. Cheap land is also a very big factor. TSMC purchased over a thousand acres. Where else in the US can you find a thousand acres so near a populous area and so easily accessible off a major freeway like that?

Tax promises and Trump trying to sway the state for the 2020 election had more to do with the choice than anything I think.

the west coast also has a pretty low incidence of natural disasters. The east coast regularly gets bad hurricanes, the northeast and midwest get really bad snowstorms, plains states regularly get tornadoes, etc, but on the west coast if you pick a region that's not geologically active then there aren't really a ton of huge natural disasters that occur regularly.

of course I guess there's wildfires now too, but that's not really an Arizona thing either.

of course you're not wrong about companies often being lured by the particular states that are willing to offer them massive tax breaks, in some cases even to places like Texas that do get hurricanes on an occasional basis. And that doesn't always work out well in the end like with the Texas power outages that seem to be occurring more and more frequently, there are a LOT of fabs in Dallas/etc that are having to deal with widespread power outages multiple times a year.

(you're the expert here but it seems like the generator capacity usually isn't sufficient to continue normal operation of the fab, it's more to maintain containment/purity of the feedstock and you still lose wafers that were in-process at the time? that's the impression I've gotten at least)

No semiconductor site has enough backup generators to run continuously and you can only have so much diesel onsite to run those generators (a few hours or maybe a full day if you are lucky). They are there for basic safety systems, air handling and lighting. For example Samsung was down for many weeks after the February storm that caused power outages and fuel delivery issues. They literally ran out of diesel to run the generators and their cleanroom air stopped circulating. It took weeks to get things back to normal and my understanding is getting the air quality back was the hardest part.

https://www.zdnet.com/article/samsung-reopens-austin-chip-pl...

Your comments in this thread have been really interesting to read and I thank you for taking the time to respond to us all!

> the northeast and midwest get really bad snowstorms

I’m curious what the supposed issues around snowstorms are. In the Midwest at least you typically lose a day of “work” (not going into the office) a couple times per winter and that’s only because of school closures. The roads are rarely an issue for more than a couple hours unless it’s REALLY bad storm.

I don’t see why you couldn’t keep running the fabs through that.

Power bumps are a major issue and even with redundant power you get them. Even a bump that loses 15-20% of voltage on a single phase for 3-6 cycles (of 60Hz, so like 0.05-0.1s) is a huge impact to fab production tools.

I've seen impacts from cars hitting telephone poles 20 miles away that have been enough to impact the fab, let alone tree branches snapping from snow and ice.

I guess I don't know why this would be an issue - you just pick an area that uses buried power lines, and there are plenty of them. And ignoring that - if you're Intel building a fab, you setup shop near one of the major transmission lines that run well above the treeline. Or build your fab just down the street from the power plant...

St. Cloud, MN. Palo, IA. Brownville, NE. Burlington, KS. - nuclear plants.

I'm sure they all have plenty of cheap land to put fabs up on and if you take one of the norther states you'll cut your cooling bill to less than zero for several months out of the year without any evaporation.

Just having underground lines doesn't stop everything...and no one has underground lines for extremely high voltage.

re: West coast - one of the big wild fires got within five miles of Cupertino two years ago, local friends got evacuation notices before the fire was stopped, and all homes and I imagine even manufacturing buildings have to be built to withstand an earthquake all along the coast.

Everything is built for seismic safety, but that doesn't mean you won't have to scrap a ton of wafers or have any damage if there is an earthquake.