Renewable and Appropriate Energy Laboratory

The argument is that solar power mounted on individual family roofs typically costs 25¢ per kilowatt hour or more (and sometimes more than 40¢ per kWh) - far more than many other options to reduce greenhouse-gas emissions - and thus state and local solar photovoltaic subsidy plans are not the best use of scarce resources.

The problem with this argument is that it true only in an economic system built around the public utility model we are used to, not the innovative energy system we could have.

Today the carbon dioxide concentration in the atmosphere is about 385 parts per million -- more than 100 parts per million higher than before the Industrial Revolution. Just when and where the climate will begin to change in large, unpredictable ways remains a threat that all our environmental models say is coming, even if they cannot be forecast with any real accuracy.

This week has seen world-wide unrest over food prices and mounting criticism that biofuels, which are mainly derived from food crops, are furthering a surge in these prices and have a negative impact on the environment. We take up the debate.