The race for renewable energies may introduce an unintended consequence with negative implications for the world.

Sixty years ago, nuclear fission was hyped as a source of electricity that would be "too cheap to meter." The OPEC oil embargo dashed most expectations for bountiful low-cost energy but, in 1989, Pons and Fleischmann proclaimed that their cold fusion system could generate unlimited electricity. Once again, the worlds eyes glazed over with the promise of more bargain-basement energy than we could ever use.

I have been involved in renewable energy since the 70's and the cold fusion vision prompted me to pitch an editorial entitled "Is our world ready for cold fusion?" I argued that a promise of unlimited and/or cheap electricity would have the unintended consequence of accelerating depletion of our planets mineral resources, by untethering the major economic constraint on their exploitation.

While lay people can be excused for not understanding the complexities of supply vs demand, thermal vs electric, intermittent vs dispatchable, and many other energy interactions, all advocates of sustainability (including supporters of renewable energy) must argue first and foremost for the most appropriate use of any energy in every application. Only after energy demand has been minimized, should we argue for supply of green power from solar and wind, green heat from geothermal and bioenergy, and green fuel from ethanol and biodiesel.

The growing calls for a transition to 100% renewables fail to explain that electricity supplies only 20% of secondary energy. There are huge downsides to investing trillions of dollars to electrify our society where pure-sine-wave carriers are used for low-grade applications, but the promise of full renewable energy also has the potential to open a Pandoras Box.

Solar and wind are inexhaustible; if technology vendors promise to install sufficient capacity to meet all our current energy wants, how long will it be until the public wants us to go beyond 100%? Cheap or excess supply will increase demand to feed consumerism, and the last innovation our globe needs is an easier and cheaper way to deplete its finite resources. Low-carbon is better than high-carbon, but unless Plan B involves relocating to another planet, we must look beyond the immediate crisis of global warming (it is a crisis and it is anthropogenic) and consider the wider implications of replacing one energy addiction with another.

As I warned a quarter-century ago, any claim that energy could be (or should be) unlimited and free is not a goal which advocates of renewable energy should promulgate. The potential for green heat (technologies to provide space conditioning and water heating) and green fuels (alternatives to gasoline and diesel) to displace energy consumption and reduce GHG emissions are much higher than green power, but the public only understands electricity. Promising to expand hydro dams, windfarms, deep geothermal drilling, large solar PV plants and other low-carbon generating facilities, without a prerequisite demand for maximum conservation and efficiency, could potentially harm humanity by eliminating one of the few controls on the exhaustion of our planets resources.