Abstract
A global economy powered by non-solar energy sources is limited by global warming, finite reserves and concomitant insults to the earth's biosphere, including our own species. Some of these impacts, such as loss of biodiversity, will be irreversible. Without constraints on the reproduction of capital, the global driver of the contemporary environmental crisis, these impacts will intensify. This is not a necessary outcome for an economy utilizing the high efficiency capture of solar energy, a conclusion informed by consideration of the heat budget of the earth's surface and the laws of thermodynamics. Such a solarbased economy managed by containment of the socially modified environment is a necessary condition for a global civilization realizing the Marxian concept of communism.