The Limits of Energy Innovation

Winnipeg – President Barack Obama has promised an energy revolution in the world’s largest economy, with renewable sources of power and “green” technologies breaking America’s – and ultimately the world’s – dependence on conventional fuels. The environmental, strategic, and economic benefits – including lower use of carbon-emitting fossil fuels, less reliance on politically volatile oil-and-gas exporters, and the creation of millions of well-paid jobs – are uncontroversial. But how realistic is this vision?

There is only one kind of primary energy (energy embodied in natural resources) that was not known to the first high civilizations of the Middle East and East Asia and by all of their pre-industrial successors: isotopes of the heavy elements whose nuclear fission has been used since the late 1950’s to generate heat that, in turn, produces steam for modern electricity turbo-generators. Every other energy resource has been known for millennia, and most of them were harnessed by pre-modern societies.

The fundamental difference between traditional and modern uses of energy consists not in access to new or better energy resources, but in the invention and mass deployment of efficient, affordable, reliable, and convenient “prime movers,” devices that convert primary energies into mechanical power, electricity, or heat. History could be profitably subdivided into eras defined by the prevailing prime movers.

The longest span (from the first hominids to the domestication of draft animals) is made up of the age when human muscles were the only prime mover. Then came the addition of draft animals and gradual supplementation of animal prime movers by mechanical prime movers, such as sails and wheels, that capture natural energy flows.