So prove me wrong. Build an "ocean energy harvester." Learn the hard way, as tens of thousands of other perpetual motion believers have.
This bizarre fear and preoccupation with perpetual energy devices has nothing to do with physics or more specifically fluid mechanics.
I already know it isn't a perpetual motion or energy device, why don't you?
Once again, it is not a source of energy, any more than a rock is. It doesn't work as a source of energy in real life. Note the last three words there; they are important.
You still haven't explained why you think it is a perpetual motion device...
Yes, he (and everyone else) has. It's the First Law of Thermodynamics. You are trying to create more energy than you are applying (otherwise why do it?). It can't be done at a fundamental level. It's not a matter of bringing costs down one day. If that were the case, that could possibly be done. That's not the problem being addressed here.
Wave power technologies, which at least are realizable in principle, are a dime a dozen. There are many startups and proof-of-principle projects that get initial glowing prognoses and seed capital, but subsequently 'disappear beneath the waves'. About every conceivable angle has been explored. To come up with something truly new and viable is a huge ask. At best it represents a niche technology, with inherently high overall maintenance costs, that could never make a significant contribution to global energy requirements.
I agree with most of your points but, in principle, it is similar to wind turbine technology is it not? Of course that isn't making a significant contribution either but it is commercially viable although maybe that is only due to government subsidies?
Putting it simply, operating in the ocean is just harder than on land. Probably why the cost is so high, and why companies abandon their plans. It's a cool concept, though.
Yes I think so. Senility, probably.
Wind contributed about 25% of electricity generation in the UK and Germany last year.
Yeah, I've seen about a dozen designs for those, from shore-mounted rams to floating buoys to long serpentine buoys that flex as the wave passes. The problem all of them face is that they are trying to harvest moderate amplitude, very high force but very low frequency energy. And that generally requires very heavy equipment, which doesn't translate to "cheap."
I've read that wind energy is becoming more cost competitive, too.
Wind turbines are a mixed bag. The current crop of tri-bladed ones that clutter the landscape in many countries have serious drawbacks. At least according to some serious studies:
The bladed designs that I've seen tend to be in places where either land isn't all that valuable or it's hilly and not useful for farming. They are all over Kauai but they are in hilly areas where it's too steep for houses. You can say they are a visual eyesore but that's subjective I guess.