2023 Prius Prime: Charging Mode Rate

I think that's a bit of a leap. I suspect keeping the ICE in an efficient rpm/load level is a big factor. In normal cruise it won't want to push the ICE too far away from the efficiency it would achieve normally for the requested wheel output.

As you saw, when accelerating, it was happy to push all the way up to 11kW, presumably because it was already resigned to have a high-revving engine.

You should retest with other steady speeds. It may be coincidental that efficiency at 40mph is roughly 3kW.

And quite possibly it may be that 3kW is actually the minimum. They don't want it to charge slower than a wall charge.

The rule may be something like "min 3kW, max 11kW, do not reduce engine efficiency by more than X".

 

charge mode ( --- to 80% SOC) can also be compared to wall charge (--- to 80%) time. ie: find the speed where charge mode takes the least amount of time to charge the traction pack from (--- to 80% SOC) than time the same charge from the EVSE, either or both 120 , 240 volts. The Gen 4 Prime averages around 8 amps close to 9 amps at 240 volts Level 2 (8.8 or 8.9 amps at the very beginning) tapering to low 8. amps for 1,5 hours, than another half hour at much lower amps, 2 or 3 maybe, I'll have to watch more closely next time.
So if it takes charge mode around half and hour to charge from (--- to 80%) that is quite a bit more than 3.3 kWh in the Gen 4.

 

I agree that charge mode is quite a bit more than 3.3 KW. Charge mode is a DC to DC charging operation. It's source is MG1 rated a 22.5KW . Not all the power derived from MG1 is devoted for battery charging in charge mode , but still it is greater than 3.3KW ...never did a 0-80% SOC in charge mode...but occasionnaly i do use it to burn some old gas and the charge level increases quite rapidely

 

I'm guessing the 3.3kw is the limit of the conversion from AC to DC?

From a vacation in a hilly area, it can definitely charge faster from traction braking than you can charge it on a charger. There were a couple of times we were regenerating far faster than we could have charged it. I think we got 10% in like 10 minutes driving down Mount Holyoke in B mode.

 

It is for the onboard charger the Prius Prime is equipped with.

 

Is'nt it odd that 45 to 70 mph the FE is the same 38 MPG?

I'm looking to evaluate the cost of the kWh obtained with Charge mode: what would be the FE in Hybrid mode to compare with the 38 MPG?

 

There's a discussion in another thread about the Indicated MPG vs real FE (from refueling).
In my experience with Toyota Hybrid, the Indicated MPG is affected by the same % of optimism of the speedometer, and I'm not the only to believe so. The value is in any case very close to most attempts to measure the tolerance using refueling.

This is the most interesting data for me, and 43.5 MPG sounds very interesting and efficient, if we have to think of some 50-52 MPG in HV mode at the same speed. What you reckon you could achieve in HV mode in the 45-55 mph range?

 

Thanks for your replies @tovli, i do not know the prices of the kWh at US charging station, but i found myself with very high prices and long waiting time (and going back and forth to free the station) because of the very slow charging speed of the Prius.

So i reckon that after a highway long stretch leading to a city, it should be cheaper and faster to use the charge mode for some city EV driving rather than charge at a station.

EV mode from a public charge station will cost me 0,69 Eur/kWh (0,75$/kWh)....
As soon i get the car i will drive the same route in HV and Charge mode to evaluate the cost of the kWh using gas (8.2 $/gal here)...