GM is currently leading in one eco-technology, although other automakers will presumably be fast on its heels. In 2013, the auto manufacturer will begin using a new refrigerant (HFO-1234yf) that is a huge improvement over its predecessors.

Refrigerants, like CO2, produce a greenhouse effect in the earth's atmosphere. What compounds the effect is how long they take to break down: the refrigerant currently in use, R-134a, lasts on average more than 13 years, resulting in a global warming potential (GWP) of over 1,400. The soon-to-be-implemented HFO-1234yf, in contrast, lives only 11 days, resulting in a GWP of 4--an improvement of 99.7%.

The refrigerant is made by Honeywell. More information on GWP here. (photo courtesy of GM.)