I've admired nuclear fusion, but tapping into the geomagnetic field and using the earths core looks like the real way to go, and it's quite possible the current grid can be retrofitted to accommodate it. Nuclear fusion, as you said, though a great idea for transportation and possibly backup powering the substations themselves, is not viable at all on a distribution level since it dissipates too quickly. And best yet, GM has zero impact on the environment, cleaner than solar and wind combined. You may know more than I do on this subject so I'm open to other opinions on it.

As a kicker, I've cryptically believed the swastika itself is the blueprint to a device that could produce infinite energy, using magnets