The tides are not "perpetual": they depend on gradually taking energy from the orbit of the moon.

> And the finding might lead to new applications — such as, essentially, ice-filled wires — that take advantage of the unique electrical and thermal properties of ice while remaining stable at room temperature.

This tidbit of Science Journalism reads like a whimsical fantasy of the writer of the article after a cursory read of the abstract, rather than a statement of fact by the authors of the paper. It's important to differentiate these types of phrases when reading this sort of article.

The "thermal properties" here do not seem to actually include the temperature; they're heating it up to measure the melting point of the ice they form. There's no indication that it spontaneously changes temperature when exposed to this physical phenomenon, nor that the ice remains solid when returned to the liquid water, nor that the process generates a constant flow. If these things happened, I would definitely expect the paper to focus on that application.

More generally, any idea which would violate the laws of thermodynamics should probably be dismissed as a misunderstanding of the system. It's good to be curious, but you should also be skeptical.