In one of the PiP threads someone asked when will the EPA do the MPG testing of the Plug-In Prius. It was an eye opener for me to find out that the EPA does NOT do the testing. The manufacturers do the testing and then the EPA reviews it. Here is a question I sent to FuelEconomy.gov a few months ago and their response: So, Since Toyota has already updated the MPG figures for the Plug-In Prius, we already know what the EPA figures will be.
Does anyone know if the 95 mpg was determined while the Prius was operating exclusively in EV mode, rather than a blended mode over a greater number of miles?
The 95 MPGe is a blended number. See Toyota's website: 2012 Toyota Prius Plug-in Hybrid Performance and Specs choose MPG, then click on [5].
While it's true that the manufacturers are the ones who provide the EPA numbers (following the EPA's test methods), the EPA does do periodic audits to make sure that the manufacturers are not lying about the testing results.
Thanks for the reference to their website which states: "2012 EPA combined estimated miles per gasoline gallon equivalent. Estimate includes consumption of electricity and gasoline energy during EV mode operation. Actual results will vary for many reasons including driving conditions and how you drive and maintain your vehicle." After reading that statement carefully, the skeptic in me reads that during EV mode operation, it uses both electricity and gasoline, which we know from the demo cars. To me this implies a best case scenario in the EV mode. It does not state a blended EV and HV situation. My wife's commute is 10 miles, round trip. I would expect her to get that MPG. It would be useful if there were common standards set to measure this; i.e. 200 miles for example, as the basis for comparison of different manufacturers. It appears that each manufacturer can advertise their best case scenario, rather than real world situations. Very soon there will be many folks on this Forum who can speak with real world experience. We are all more informed buyers thanks to everyone here.
Yep. OP should read http://priuschat.com/forums/other-c...uth-about-epa-city-highway-mpg-estimates.html. Given the above article, it seems very likely the EPA would decide to pick out the '12 HyCam and PiP to confirm the results.
I think you have it backwards. Having to include gas to calculate the MPGe drops the MPGe number significantly and is not a best case scenario. Also, it sounds like you are interpreting MPGe as "miles per gallon", which it isn't. By that I mean, 95 MPGe on a 10 mile commute does not mean consuming 0.105 gallons. A 10 mile commute may be done entirely on electricity depending on the speed of the commute, in which case kWh/mi is the metric for EV efficiency. Alternatively, it could consume gas if it is 62+ mph.
