like it or not, some form of carbon tax will be in play, if not through penalties for high emissions of co2 or via the epa. in 2007 the us supreme court ruled that co2 is a pollutant and the epa has a right to control it, just like sulphur dioxide. nothing has been done yet by the epa, i believe it is waiting for congress to act. if it doesn't then they will step in.

this may mean more power producers will go to alternative energy to avoid any costs of emissions. alterntive energy will require storage for off times. this may mean sales for zbb.