And the source of oil differs depending on the region of the country you live in.
The U.N. agreement -- still to be signed -- would cut mercury in power production and common manufacturing processes.
Remember when technology was going to shred our social fabric? Well, here’s an example of how it might be doing just the opposite.
A reader wonders if it’s unethical to hang on to Big Oil stocks, and if shareholder activism does any good. Umbra offers some centsible advice.
On display at the Detroit Auto Show is evidence of gas guzzlers adopting fuel-saving technology made famous by the Prius.
The 787 is designed to be a "super-efficient" airplane, but the batteries that make that efficiency possible have been causing big problems.
Hardcore bikers want to keep pedaling to work even in snow and ice, but most of them also want to make it there with intact skulls.
Canadian pipeline company Enbridge is losing business as oil companies increasingly ship their product by rail instead of pipeline.
The military is working to make its bases energy self-sufficient through the deployment of "microgrids." What it learns will be useful to civilians as well.