Actual MPGs - Anyone Filled Up, Calculated?

Thanks for correcting me. Sorry LurkAzusa. I should really know better than to use sexist language

 

It will probably depend far more on the drivers EV% than on the kit vs OEM. An Engineer kit used with a light foot and a short commute, recharged at work, can do very well. The bigger question will not be known for years.. which is about battery life.

Would be interesting to get a standardized comparison. someone with a kit and someone with a PiP do drive the same route/speed.

 

Very small impact:

=1/(.05/43+.95/50)

49.6 (1dp)

Incidentally, you should really bump up the 50, since the 50mpg rating includes some cold-start hit.

EDIT: actually, since 49.6 is the real combined rating of the Prius, 50mpg is already bumping it up.

 

Cheap kit...well, sign me up...I would like this "Cheap" Kit. How much?

 

Cannot answer about engineer kits, but I have friends with
Boulder Hybrid Conversions kits
which for CO residents with the state rebates they are a great deal and close enough that the install is easy.

One has a 4kw pack (which was net $750 in CO, $5K list) and is averaging about 70mpg. (Better in town, but things are far apart in CO). The other sprang for the big 10kw pack ($12K list $5.5K in CO) and last summer was getting about 100mpg. (Never asked how it does in winter).

 

If I'm not mistaken, and I may be, the Boulder Hybrid Conversion kits are: 4KWh - Enginer kit, and 10KWh - Hymotion kit. Anyone who knows otherwise is free to correct me.

 

I can't way for the PiP kits, slap another 10 kwh in there and you may have something.

 

Thanks for updating me. Dug a little. Looks like 4kw is engineer and 10kw is based on plug-in-supply systems. See this thread

http://priuschat.com/forums/prius-p...-conversions-plug-in-systems.html#post1270288

 

Drove the car down to estimated miles remaining to 0: Here are the results

Tank Fillup 8.826 G
ODO 725.9 Miles 82 MPG Avg Speed 28 MPH

I calculated by hard MPG to 82.25, so Prius computer was very close

Other Info
38% EV 276 Miles 66 KHW
62% HV 443 Miles 8G (Must be rounded down to whole #)
Fuel Saved 5.5G

Again the computer was accurate

Only weird thing I see happening now is the estimated miles for EV Mode after a full charge keeps dropping. It stated at 13.4 and now after a charge is showing 12.1 to 12.2. It has gotten a little colder since I got the car on 2/29, but not sure if that is the reason my estimated EV distance is dropping. I have a Kill-A-Watt and I would aware the car is not sucking as many watts as it did a week ago. It seems to be full at 3.08 watts. I thought a week ago I was getting 3.44 which could explain the difference in distance.

 

We need a format to document our numbers.
Has anyone started a system that's working for them?
Maybe we could use a tab on the Excel sheet used for the PIP Order info?

 

Can the PiP do blended mode at any speed? to maintain 100+ mpg for longer range?

 

Excellent EV to HV ratio.

23.9 kWh/100mi and 1.99 gallon/100mi (50.2 MPG). Electricity consumption is very low and the gas mileage is right at the EPA figure.

It said you saved 5.5 gallon of gas using 66 kWh of electricity -- less than 2 gallons equivalent.

 

As to driving 1/2 of miles on EV and getting ~100MPG (assuming 50 MPG in hybrid mode): That is what one would expect. However, this morning I was driving 4 miles on pure electric (MPG showing as 999). Just before the freeway I decided to turn off EV mode to conserve some charge for later city driving. Within about 10 seconds my MPG dropped to ~100MPG. Granted the engine was cold (outside temp was 50 degrees). Mathematically my hybrid mode MPG must have been around 2.5MPG(!) during those initial 10 seconds to bring down overall MPG to 100.
Is the engine startup cost truly that high that it kills my MPG within seconds?

PS: After another 4 miles on hybrid MPG settled at ~60 MPG, meaning my hybrid MPG during those 4 engine warmup miles was ~30MPG.

 

Lets not forget most of the people reporting are in California and probably running crappy 10% ethanol gasoline...

 

After various driving method on my converted Prius I've found that starting your trip on EV then later blended mode actually gets worst mileage than start driving in blended mode then switch to EV mode toward the end of your trip. The ICE on the PiP is no different than a regular Prius. First 5 miles is horrible. You'll get probably 40mpg if that.

If the PiP has blended mode at any speed, you can maintain 70-90 mpg during warm up cycle. By the time your engine is warmed up enough to get good mileage, you're cruising at 100-150mpg. By the time you're done with your 15 mile trip you're left with 100+mpg and a warm engine with half charge left. If you drive the last 5 miles in EV, you can easily get 120+mpg. If you do this everyday, you can easily get 1000+ miles per tank.

 

Unfortunately at least to my knowledge the PiP doesn't have a blended mode. In EV mode the car stays in electric if it can (i.e. not going too fast, acceleration not too extreme) and in HV mode it does not use electric at all. So one has to either start all electric or all hybrid. Either way the warm up during the 8 non-electric miles in your example will drastically reduce your average as in my previous posting - I haven't had a chance yet to drive a 20 mile trip with a full charge, but I would expect the overall MPG to come to ~90 for the PiP.

 

I don't think that's true. Here's a thread that discusses blending. Seems there are people who have experienced blending:

http://priuschat.com/forums/toyota-prius-plug-in/104701-blended-hv-mode-all-speeds.html

 

Can you share how you did the math?

 

Great - thank you so much for the great pointer! I tried this out today and it seems to make a significant difference. I did the following: Start out in electric (optional - in my case I have city driving at the start of my route so it makes sense to start in electric). Then instead of using up the entire charge and letting the PiP automatically switch over into HV mode briefly toggle from EV to HV and back to EV a few minutes before depletion of the charge. As described in the thead Tracksyde referenced the engine comes on but the car continues to drive mostly on electric and continues to use up the electric charge as the car is still in EV mode. This blended mode indeed seems to provide a very efficient way for the engine to warm up. My MPG showed as ~75MPG for the 5min interval that contained the warmup.
In my original post I drove 4 miles electric, then switched to HV and after another 4 miles in HV ended up with a total of ~60MPG. With the above I should be able to go instead 1 mile electric plus 3 miles blended at ~75MPG for a total of ~100MPG, then add 4 miles HV with a warmed up engine at 50MPG for a total ~75MPG for the 8 miles. At least in theory - can't wait to try this out!

 

Sure - I calculated backwards, but it's easier to explain calculating forward and proving my number is right, so let's assume my statement that I got 2.5mpg during the initial 10 second warmup is correct:

During the 10 seconds with the engine on I was going about 35 m/h, i.e. I covered about 0.1 miles.
Going 0.1 miles at 2.5 mpg uses 0.04 gallons of gas. Then the overall mpg for the 4 miles plus 10 seconds is: 0.04 gallons of gas for 4.1 miles equals 102.5 mpg, which is roughly the 100mpg is observed (i.e. my assumption of 2.5mpg is correct).