I assume by "limitless" you actually mean "more than we human's could ever use"
Yes.
Cold fusion has never been achieved in any verified experiments.
Cold Fusion effects have appeared in hundreds of experiments. A leading NASA scientist (Dennis Bushnell) has also confirmed that Cold Fusion is real and the most promising future energy technology.
Vacuume energy, as far as we know, can not be harvested for 'free energy'.
That is what the governments and big energy companies want you to believe. Many inventors, engineers and scientists have proved otherwise. They are just not recognized by the established scientific journals and universities because they are also under the control of these same interests.