I’m not convinced that a prize is particularly helpful in this case. I think of prizes as useful for inducing investment in things like public goods where private returns are limited. That doesn’t seem to be the case here; successfully creating “radically better energy generation” seems like it would be wildly remunerative. The promise of vast wealth seems like it ought to be sufficient incentive regardless of a prize.
OTOH, that’s all very first-principles and the history of innovation prizes doesn’t seem to really pay much attention to this line of criticism. Maybe prizes make particular problems more salient, etc.
Another good point, though the relative neglectedness of the field suggests we could use the help of a Prize to “awaken possibility” with potential innovators and investors. Challenging them to think about (and act on) ideas that they’ve never allowed themselves to further develop.
Paradoxically, vast wealth can also be an inhibitor for sharing one’s progress once attained. Especially when innovators come from unusual backgrounds, discussions with possible investors may never be successful due to a lack of trust and/or an overwhelming difficulty of “putting a price” on an invention. There are precedents of this ; some potentially valuable inventions have never made it beyond the lab of the original inventor for such reasons.
Perhaps the true value of the Prize, however, is scientific recognition. There are several inventors / startups today who struggle to find investors despite promising technological advances. If any of those were able to win the prize, which implies thorough scientific scrutiny, then raising subsequent capital would become much easier. (A sizeable cash amount would still be needed to give the Prize sufficient standing).
It is also possible that the winning technology is not (yet) sufficiently commercially interesting for private investment, but sufficiently convincing to warrant a major international research effort.
Finally, a Prize is also about simply trying something new. If clean energy is one of our greatest challenges, then formally asking the question whether anyone has some potentially important technology would seem to be a rational thing to do.