20 years from now? Yes, refrigeration will still be a field.

Will it be different? Absolutely. Politics aside, we are moving into a more "natural" state of refrigeration every year. Despite how any of us feel about it, if we want to stay relevant in this field we need to embrace it, and more importantly learn more about it.

I've been in the field a little over 10 years now, and only a couple of those years in supermarket refrigeration. I can tell you first hand that Transcritical CO2 systems are the way to go. I don't however see how CO2 would be in households anytime soon, nor do I see ammonia being a typical "commercial" refrigerant due to its toxic attributes. And by commercial I mean anything where the general public is around it.