Democratic presidential candidate John Edwards says school buses using bio-diesel could help cut greenhouse gas emissions, improve public health and reduce dependency on foreign oil.
The former North Carolina senator wants to replace 100,000 school buses with bio-diesel vehicles.
It's a part of the former North Carolina's alternative energy plan he laid out yesterday in southern Iowa.
Edwards calls for making bio-fuels more available and building more cars that use them. Edwards also wants to raise fuel economy standards to 40 miles per gallon by 2016.
Edwards says he'd require oil companies to install bio-fuel pumps at a quarter of their gas stations.
In all, Edwards says he would reduce the nation's oil imports by 7.5 million barrels a day by 2025.