I think there’s some possibly good investment advice to extract here, if you’re able and willing to invest in fusion startups: based on the need to compete with renewables alone, commercial success implies that highly complex reactors simply may not have a market based on construction cost, even if they do generate power.<p>Of the fusion startups mentioned in the article, I’d say that makes <i>Zap Energy</i> the one worth gambling on (if you’re a gambler that is), as its success apparently depends on exploiting a fluid dynamics effect which was not well known in the past (“shear flow”). If this sufficiently solves the confinement problem, the resulting device looks ludicrously simple in comparison to contemporaries.<p>Of course it may not work at all, I sure don’t know if it will; but if you had to invest in one of these, that seems like the one where successful power generation actually creates a marketable product.