Elements chemistry I guess

That would release 16,000 tons of O2 per year. While that may sound like a lot, world consumption of O2 is about 1,200,000 tons per day.

The electrolysis output could be liquified, but it seems too small to be worthwhile. Large O2 production units make 5,000 tons per day.

You would need compressors to liquefy. Industrially gases are compressed/cooled to ambient/expanded to liquefy them. You can use a cryogenic fluid in a heat exchanger to liquefy Oxygen but if oxygen is at room pressure, it will be way ineffective.

There was a company called Q-Drive making thermoacoustic chillers for small-scale oxygen liquefaction. I believe they sold themselves to Chart. And that IP was later bought by . . . someone else. I forget.

Anyway the point is there are applications where small-scale liquefaction is desirable, and there are products that serve that need. But it’s less efficient than massive ASUs, so only really desirable when transport or lots of storage are problematic.

You can make liquid oxygen at home.

But even then, you are doing it with liquification, rather than compression.