The authors found no statistically significant difference between energy efficiency improvement and renewable energy development.

A troubling trend shows other factors could begin to cancel out this progress.

Looking at the rapid energy transition needed to curb global warming, we must now achieve similar success in all other renewable sources.

How to get more electric cars on the road

It depends on the nature of the conventional power generation that renewable energy is offsetting.

Researchers from the U.S. Department of Energy's (DOE's) three applied energy laboratories co-authored the paper.

Despite the increasing practical benefits of rooftop solar, solar adoption in the U.S remains skewed toward the rich.

Their study shows that the prominent carbon emission bottlenecks in the U.S. are for transportation of oil and natural gas.