Your PIP was cleaner this year than last...

Considering the number of local BEV owners who also installed home PV specifically to offset the BEV's energy load, I'm suspecting the effective 'cleanness' is higher than shown.

 

At least around here, the total for all solar (not just home installations) is too small to even get footnote mention within 'other' on the fuel mix report. So far, the large commercial wind projects are far more significant, at 3.4% of my utility's total supply. (Under this state's law, large scale hydro isn't counted as 'renewable'. It needs to be shipped to California to gain that rating.)

If home PV is simply tossed into the grid mix, as mine is, then it has virtually no impact today on BEV cleanliness. The shift comes from other improvements in the grid's sources. But I have run into a number of area residents who installed home PV specifically because of a BEV (or larger PHEV) (or vice versa). Where that linkage exists, it seems reasonable to assign all the PV output to the BEV, making it cleaner than if powered from the local grid mix.

 

i suspect the reason is natural gas. (no, not mine)

 

The article uses BEV as example but PHEVs should also be affected to some degree.

This applies only if you look at it from regional emission point of view. I know some of you rather use your personal level (PV) system, although it is connected to the grid.

Overall, the US grid average emission dropped about 10% so it is a good thing.

I think plugin cars need to be designed with the lifetime emission. Leaf is a great example but it is not as clean as a 50 MPG Prius in many of the states.