The costs of wind, solar and biomass have declined due to steady technical advances, but in key areas of energy quality—density, net energy, intermittancy, flexibility, and so on—they remain inferior to conventional fuels. Thus, alternative energy sources are not likely to supplant fossil fuels in the short term without substantial and concerted policy intervention.

The concept of energy density and policy, I believe are misconceived.

Here is a quote from Edison, 1910:
"Sunshine is spread out thin and so is electricity. Perhaps they are the same, Sunshine is a form of energy, and the winds and the tides are manifestations of energy.”

“Do we use them? Oh, no! We burn up wood and coal, as renters burn up the front fence for fuel. We live like squatters, not as if we owned the property.

“There must surely come a time when heat and power will be stored in unlimited quantities in every community, all gathered by natural forces. Electricity ought to be as cheap as oxygen...."

Edison, in this interview explained the task he confronted was to store electricity and let it out in usable measure. Electricity in Edison's time was a low-density source, except lightning which he noted was not very useful. Sunshine is today a low-density source, the way we have engineered power use.

Policies need to allow ingenuity that allowed Edison to create his breakthroughs. Current power generation is monopolized by regulatory agencies.

Germany’s Feed-in-Tariffs removed centralized power generation monopolies. California’s Energy Commission recent recommended Feed-in-tariffs noting that Germany added 4,000 MW of renewable generation in the last year while California’s centralized policy installed 242 MW in the last 5 years.

We are losing the game by the rules we have defined. Remove the rules and allow innovation. We can change the lifeblood of our economy from oil to ingenuity.

Innovators cannot navigate policies that block innovation that Edison did not have to confront.