Gas phase change systems in practice are up to about 60% efficiency (relative to an idealized carnot cycle), magnetocaloric systems in labs have been something like 70%, and elastocaloric 80%.
Edit: And just for reference peltier devices are usually 10-15% efficiency on this scale. So I suppose this new one is somewhere in the 20-30% range.
Some people will sleep through alarms, turning them off without remembering it.
But more importantly, if your sleep schedule is shifted you might not actually be able to fall asleep when you need to, even if you haven't had enough sleep. After a few days you will be exhausted, fall asleep in the afternoon and take a nice 4 hour nap, leaving you unable to fall asleep until very late, after which the cycle continues.
I used to sleep like 2AM-10AM, and something I realized towards the end of that phase of my life was that it was easier to be productive at 9AM than it was at 12AM. And coming downstairs and encountering people who have been awake for 3 hours and are in the "middle" of their day, having done productive things already, was fairly demotivating.
Ha, I mean that’s not the only line I wrote, but a lot of people give themselves the option of not actually doing the thing, or doing something else in hopes that they’ll somehow develop motivation. Anyway there’s lots of other advice here you can take if you’re looking for it.
Do you know by how much?