Hey guys, so the MPGe number is the efficiency when the engine is off and the car is being propelled completely by electric power from the smallish lithium ion battery pack, and regenning when braking on the EPA test cycle except for when braking is too aggressive and mechanical brakes help. Alright, so it's an even playing field compared to other EVs/plug-in hybrids/range-extended EVs. The following numbers are the combined city/hwy EPA MPGe numbers. So, the plug-in Prius weighs 3,165 pounds according to Toyota's spec page. The Leaf is 33xx pounds, yet the Leaf gets 115MPGe and the PIP gets 95MPGe, the ~3700 pound Volt gets 98MPGe Fit EV gets 118MPGe. So why does the light weight aerodynamic Prius PlugIn only get 95MPGe? -Is it really less efficient than most other EVs or is it a fluke of the test? -Why is it a fluke? --> All combined EPA MPGe numbers are results from the 2008+ 5 cycle EPA test right? None are done with the old 2 cycle or whatever test? or -Why is it less efficient? The E-CVT I think is very similar to the Volt's and the inverter and electric motor ought to be competitively efficient. Other EVs use a single speed tranny. It doesn't make sense. Thanks
I think the issue is that the EPA test in question has a "hill" that too "steep" for the PiP to handle in EV mode, so, as designed, the ICE kicks in to help. OTOH, the Volt is designed to not run the ICE as long as there is battery charge except in extraordinary situations, so the Volt ICE does not kick in during that test. Different design philosophy. The Prius is a hybrid on steroids, mixing electric power and ICE as appropriate. The Volt is an EV with an ICE to extend its range.
OH! Right, if you press on the accelerator too much the gas engine kicks on even if you have a full charge. So the PIP MPGe number isn't a pure electrically driven number. I guess the KWH equivalent gasoline consumption is added to KWH energy used to recharge the pack after the test and brings down the number. But that's not apples to oranges. Maybe if they redo the test with the PIP out of gas it'll still provide enough propulsion to pass the EPA test but get a higher number.
As others said, I am thinking Prius is actually quite efficient in EV mode but EPA number is using gaso for some part. I had thought it would be better to put on label 100% gaso MPG and 100% elec MPGe which if we had that number, Prius would look like most efficient.
Head over to the Top 20 MPGe thread to see what various people are getting for MPGe on EV alone. Then head to voltstats.net and check out their numbers. The PiP is a little bit more efficient in EV than the Volt. Not sure about the Leaf though or others. Personally I am averaging over 170 MPGe in EV only and that is even taking the conversion loss from the wall into account. (not sure if voltstats.net does that or not).
EPA says PiP 29 kWh/100 mi Volt 35 kWh/100 mi Leaf 29 kWh/100 mi Ford Fusion 34 kWh/100 mi The EPA assumes 0.2 gal of gas per 100 mi for the PiP for reasons stated in postings above. You can easily go 124 mi in the PiP all EV before using any gas depending on your charging/trips. And then it won't use 0.2 gallon because that is 10 miles and it doesn't take anything close to 10 miles in HV to do the required engine warm up. So depending on your charging/trips the PiP is more efficient... or not.
