There is such a point, but it’s so rare it’s hardly worth worrying about. I deal with such things every once in a while as a part of my job, and so far, I’ve seen one (1) case in which someone trying to patent a free energy device, by complete accident, managed to (re-invent) a real device, that helped to clean the water used in the free energy device. So, yeah, it can happen that these people come up with something new and useful, but it’s so unlikely that I’m not going to worry about it.
We have no use for “engineers” who don’t understand the laws of thermodynamics.
We (the collective) already have an outsized regard for the opinions of non-expert outsiders. We could stand putting our experts on a slightly higher pedestal.
Sure, there might not be much use for fanciful visionaries in the field of engineering, but that not the whole world.
There is, I believe, a need for people who are willing, in general, to try things that everyone else thinks will just fail. They’re not going to break the laws of physics, but in the domain of ‘trying stuff that might fail’, trying to btlreak the laws of physics is only a tiny part.
There’s actually a few classifications for perpetual motion machines under the International Patent Classification system, “H02K 53/00 Alleged dynamo-electric perpetua mobilia”, “F03B 17/04 Alleged perpetua mobilia”, “F03G 7/10 Alleged perpetua mobilia (using hydrostatic thrust”, “H02N 11/00 Generators or motors not provided for elsewhere; Alleged perpetua mobilia obtained by electric or magnetic means”. There’s probably some overlap between these classes, but it gives us something concrete to look for.
Searching on those classes in a database that collects patent documents from most of the major offices in the world, I get 1106 applications filed in 2021. Some applications will exist in several countries, but this search engine treats them all as members of the same “patent family”, so we’re likely to have 1106 unique hits, even though the actually numbers of applications world-wide would be higher, due to such duplication between countries. For example, US published patent application US20210257895 is also filed as an international application, a Canadian application, and has a second related US application.
Expanding my date range from Jan 2011 to Dec 2021, I get 15280 hits, so 2021 is a bit below the ten-year average, but not by a lot.
So that gives us an minimum for most of the world, for people serious enough to pay money to promote their idea. About 1500/year, on average.
THanks! I appreciate the real effort to provide your guess. If you read through the comments, most haven’t been terribly helpful
No Problem, as I mentioned, such things are actually a part of my job, and I rarely get a chance to geek out on them.
Some applications will try to be clever, and hide their essential nature behind a wall of bafflegab, but it’s amazing how many seemingly serious people are still trying to patent classic PM schemes.
Consider the application I mentioned above, US20210257895 “Systems and methods for generating electricity”. This is the abstract:
Provided herein is a system for generating electrical current including a transducer subsystem having an upper end and a lower end, the transducer subsystem generating electrical current responsive to objects being dropped individually from the upper end to the lower end under the influence of gravity; and a return subsystem for returning a plurality of the objects collectively to the upper end using upthrust through a fluid body. A method for generating electrical current includes dropping objects individually from an upper end to a lower end of a transducer subsystem under the influence of gravity, wherein the transducer subsystem generates electrical current responsive to the dropping; harvesting the electrical current; and returning a plurality of the objects collectively to the upper end using upthrust through a fluid body.
Anyone who has spent any time reading PM ideas is saying, “Yep, seen that before!”, but this was filed just last year! And the guy doesn’t even sound crazy if you read some of the application. You can download a copy here if you’re keen.
And just now re-reading your OP, I see you ended up at about 1500/year, so man, good guess! 
I can tell you for sure, that “Yep, I’ve seen this before.” Maybe this type 3 times in the last 5 years.
Isn’t that this?
Yep! Gravity+Buoyancy shows up on a regular basis in the PM industry. Buoyancy just seems so much like the “something for nothing” you need to make PM work, that it captures the mind of quite a few people. “Surely, if I do it just right, it’ll work this time!!!”
If you google “buoyancy perpetual motion” you’ll find all sorts of discussions of this.
If we’re including all of the earnest but amateur attempts by young people worldwide, using Lego, K’Nex, sticks and tape and bits of old CD players and stuff. It’s got to be more than just single digit thousands. I’ll say 20,000
I am reminded or the Orbo, which we had a few threads about.
NEWS FLASH: It didn’t work.
Oh my. I remember Steorn. The big deal with them was not that anyone really believed them, but nobody could quite work out why they seemed so sincere.
I guess you could make one with a large tipper and a small fan work. But this system has a heat source so not valid.