Cold Fusion
From an article in Aeon by Huw Price, likening energy sources to clean water. We need to get away from fossil fuels, but there’s an enormous reputation cost for pursuing cold fusion:
We are like a thirsty town, desperate for a new water supply. What we drink now is slowly killing us. We know that there’s an abundant supply of clean, cheap water, trapped behind the dam. The problem is to find a way to tap it. A couple of engineers thought that they had found a way 25 years ago, but they couldn’t make it work reliably, and the profession turned against them. Since then, there’s been a big reputation cost to any engineer who takes up the issue.
If low-energy nuclear reactions are possible and relatively simple to construct, they could solve our energy problems instantly. There’s no reason in principle that these reactions couldn’t exist, but finding them and understanding them well enough to build energy sources around them might be extraordinarily difficult. But the practical scientific research community is so turned against cold fusion that any breakthroughs that might be made (or have been made) are ignored.