Can we please define "system"?
My definition is that it is the size of your mash tun.
Mine is 22.5 L, some small brewers are 10 hL (1000 litres)
Bigger brweries just have bigger mash tuns!
20,000 hL is 20,000,00 litres i.e 2000 cubic meters! or Tons in old money
No small craft brewey brews all thier allowanc in one gigantic mash tun!!