Externalities can be either positive or negative. For example, education has positive externalities, as well as healthcare. Subsidizing and taxing are both meth

Externalities can be either positive or negative. For example, education has positive externalities, as well as healthcare. Subsidizing and taxing are both methods of dealing with externalities, and in this case subsidizing non-carbon emitting power sources is nearly equivalent to taxing carbon-emitting power sources.