There have been a near surfeit of reports recently looking at the greenhouse gas emissions of natural gas, most of which have concluded that, to varying degrees, we're underestimating emissions, the effects of methane leakage on those, and natural gas isn't always as climate-friendly as claimed.
The latest of these has just been published in Proceedings of the National Academy of Sciences.
It's a free read, so I'll leave the nitty-gritty details to the report authors, associated with the Environmental Defense Fund, Princeton University, Duke University, and the Rochester Institute of Technology. Here's the gist of it:
We find that a shift to compressed natural gas vehicles from gasoline or diesel vehicles leads to greater radiative forcing of the climate for 80 or 280 yr, respectively, before beginning to produce benefits. Compressed natural gas vehicles could produce climate benefits on all time frames if the well-to-wheels [methane] leakage were capped at a level 45-70% below current estimates.
By contrast using natural gas instead of coal for electric power plants can reduce radiative forcing immediately, and reducing [methane] losses from the production and transportation of natural gas would produce even greater benefits.
There are two topics in there that may not be familiar for readers, so here's two posts to check out on radiative forcing and methane leakage: