Magnetism can be used to generate power. Here's a very small concept design that shows how it works. https://youtu.be/jiAhiu6UqXQ No harmful waste, no pollutants, no crazy tech. The biggest problem is that energy companies will burn down your Warehouse if they catch you trying to sell it, or any other perpetual motor energy that you cant be billed monthly for. It's happened.
I suspect that is hokum. People from time to time come up with perpetual-motion machines. Our current understanding of physics (often mainly conservation of energy and 2nd law of thermodynamics) suggests that there can be no perpetual-motion machines. In history, as far as I know, every time a perpetual-motion machine is tested, it is found not to be so.
In the case of that video, the guy spins up the fan and then uses it as a flywheel to power a light bulb. When you spin up something, you are taking energy from one source (in this case a battery or power supply) and putting it into another form (in this case rotational kinetic energy). You can then draw from that rotational energy to power something else (in this case, a light bulb). But you do draw from it, and eventually you run out of the stored rotational energy. Flywheels store energy but do not create it -- you use something else to charge them up.
I would expect that, after the fan is spun up, the initial power is removed, and the setup is powering the light bulb, the fan would stop spinning after a little while. This happens once the initial rotational energy is all used up and turned into light and heat.
Magnets are not a source of energy. They are like ball bearings or springs, depending on how you use them. When they are used like ball bearings, they reduce friction (which otherwise uses up energy in creating unwanted heat). When they are used like springs, they can store up energy, but that's energy that you put in from some other source -- they don't generate the energy on their own.
In the guy's experiment, if you measured the power used up from the power source to spin up the fan and measured the power consumed by the light bulb, you would likely find that the light bulb gets less power than the amount used up from the initial power source -- in other words that the fan/flywheel in the middle just ended up wasting some of the energy (because it has some friction in its bearings, some inefficiency in its electric motor, some energy used up in moving air). He would have a more-efficient system just running the light bulb from the power source directly.