Total CO2 Emissions of Using the PiP

In another thread, I have plotted the Volt total CO2 emissions (including gasoline upstream emissions) as a function of the electrical grid CO2 intensity and as compared to a conventional vehicle (30 mpg) and to the Prius HV (50 mpg). Volt was shown in 3 scenarios of ‘EV ratio”.

In this thread, I am taking a step further:
Volt is plotted at 67% EV (being the average reported).
Plug in Prius is added in two scenarios: 20% and 30% EV.

Chart is based on EPA and other data:
Gasoline burning CO2 emissions of 8554 g/gal.
Gasoline upstream CO2 emissions of 2536 g/gal (30% of burning emissions).
Volt CD mode of 0.36 kWh/mile, CS mode of 37 mpg.

For the PiP, since no EPA data yet, I took the manufacturer estimate of 49 mpg in CS mode and 0.24 kWh/mile in CD mode (simply 3.6 kWh divided by 15 miles).
Once EPA data for the Pip is released – I will update the chart.

Some conclusions from chart:
It is hard to beat the Prius HV with respect to GHG emissions, it will be even harder to beat the Prius c (or Aqua).
There is not a lot of saving GHG by running the PiP @ 30% EV as compared to 20%, a fact that hints to “Just Drive It”.
It is quite obvious that with respect to GHG emissions PiP approach is better than the Volt approach (until such time when the electrical grid is very clean).

A sample case: the US average grid mix is estimated as about 640 gCO2/kWh (including upstream emissions), at this data point the results (in g/mile) are:
Prius HV: 222
Volt 67%: 253
PiP 20%: 212
PiP 30%: 205

Note: The chart deals with average results, your carbon footprint may vary.

 

Thanks for the chart.

My number (coming from CMU if I recollect correctly) is 30% of burning emission, that's 30/130=23% of total emissions. Not far off.

 

Good point. However I do not have data on those.