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.

Seven things Portland should do if we’re serious about being green.

Driven by public concern, all the candidates agree that action is needed to slow global warming. No matter who's elected, America's policy will be different a year from now.

Plug-in hybrid electric vehicles (PHEVs) could help reduce air pollution compared to conventional vehicles and lessen greenhouse gas emissions. Now, researchers at the University of California at Berkeley, US, have calculated that several million PHEVs could be charged during off-peak hours without the need to expand the state’s electricity grid. But to make these vehicles really economically viable, car battery prices need to come down by at least 50% or gasoline prices must continue to climb.

If potential presidents can be judged by how they run their campaigns, then how they staff those efforts may provide important clues to the kinds of talent they would recruit for their administrations. Because Democratic front-runner Barack Obama is a relative newcomer to national politics, an examination of his inner circle of political and policy advisers offers new windows into his thinking, leadership style, and sources of expertise.

This 30-second television advertisement for Senator Hillary Rodham Clinton, Democrat of New York, began running in Pennsylvania on Tuesday. It is titled “Level.”

IF the world is going to sharply reduce the amount of carbon dioxide pumped into the atmosphere by midcentury, then many businesses will have to go carbon neutral, bringing their net emissions of the greenhouse gas to zero. But some could go even further by removing more CO2 than they produce. Instead of carbon neutral, how about carbon negative?

New solar power technologies, lighter and stronger construction materials for cars and other vehicles for improved fuel efficiencies, and processes to inactivate and/or remove a wide range of toxic substances from water and soil; all may be possible through advances in nanotechnology.