"Powering the Planet" is the title of an extraordinary speech that is regularly given by Nate Lewis, Professor of Chemistry at CalTech. It is a bit long and detailed, but very much worth reading, as it elegantly frames the scale of the worldwide energy/environmental challenges to be faced in the coming decades.
The gist of the presentation is that aggressive pursuit of energy efficiency is critical -- but we still need to supply the remaining human energy requirement in some carbon-free fashion, which leaves us relatively few viable options:
Nuclear power, which concerns Lewis not for safety/security reasons but because of inability to expand nuclear utilization quickly/sufficiently to meet the world's needs.
Carbon sequestration of fossil fuel burning, which Lewis says may not be available in time or at the volumes necessary to have significant beneficial impact on climate change.
Hydro, geothermal, wind and ocean energy, which are all fine in Lewis' view, but inadequate in scope to supply global energy demands
Bio-based energy, which Lewis finds to be highly inefficient and therefore unlikely to be able to provide more than a small fraction of worldwide energy requirements
This leaves solar energy, which Lewis concludes is the best hope for the planet -- technologically known to work, scalable with no binding supply limitations, at potentially reasonable economics with continued advancement. Then Lewis closes with the clincher: if we're going to succeed with solar energy, our priorities need to change:
"In the United States, we spend $28 billion on health, but only about $28 million on basic solar research. Currently, we spend more money buying gas at the pump in one hour than we spend funding basic solar research in our country over an entire year. Yet, in that same hour, more energy from the sun is hitting the Earth than all of the energy consumed on our planet in that year. The same cannot be said of any other energy source."
Richard T. Stuebi is the BP Fellow for Energy and Environmental Advancement at The Cleveland Foundation, and is also the Founder and President of NextWave Energy, Inc.