They’re allegedly building production-ready, commercial devices. I’m deeply sceptical, but the best way to show critics wrong is to have these actually run for a few weeks producing power.
(As I recollect, of course, Fleischmann and Pons also promised cold-fusion-based household water heaters very soon after their own announcement…)
As they say, the proof of the pudding is in the eating.
And I think there’s a lesson here for FF as well. If one can indeed generate practical over-unity power cheaply, the opinion of some professional doubters won’t really matter. Utilities and companies that need remote power are pretty pragmatic — if the device works, they’ll use it.
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