Of course I agree with the spirit of the article (it's easy to see the author's priorities in the statistics he cites), but as always, one should pay attention to the qualifiers in order to see what's really being advocated. At issue is "capitalism as practiced in America," "unconstrained capitalism," and "pure unadulterated capitalism." In itself, and irrespective of the author's highest motives, this sets up a distinction between, as it were, "good" and "bad" capitalisms, where "bad" means "unconstrained" and "unadulterated" and "good" the opposite. In this sense, capitalism itself is posited as a kind of victim of its own excesses.
This is the old, familiar liberal line: it's not capitalism as such that is destroying us, but only a lack of regulation and oversight. What we therefore need to do, on this line of thinking, is to return to the kind of "constrained," "adulterated" capitalism that held sway for a few decades in the mid-twentieth century, the so-called "Golden Age" of capitalism, when there was near-universal wage-slavery, robust economic growth, and a set of rules that ensured most people got a share of the collective pie. To be sure, we need new regulations, e.g. to protect the environment, workers' rights etc. -- but the overall logic and priorities are the same, and indeed the function of these regulations is not to diminish or undermine capitalism but rather to bring it even more fully in line with its concept, its essence: "clean energy systems would create more jobs and more economic growth." More employment, more growth -- in short, the deployment of "sustainability," i.e. clean and abundant energy, as the condition of possibility of the full realization and perfection of the capitalist project.
I think the author has good intentions, though he remains far too wedded to the liberal myth of capitalism as the end of history. The problem is not "pure," "unregulated," "unconstrained," "unadulterated," "crony," "corporate," "American," or any other sort of purportedly perverted, partial, footnoted capitalism. The problem is the logic of capital itself: more for the sake of more, to infinity.