In cold temps, ICE turns on at the begining of a trip when I have plenty EV. Why?

John, that is a great video! It looks like in EV Mode MG 1 balances out with MG2. What exactly is -RPM ? Also it was fascinating to see how quickly coolant temp varies depending on EV or blended driving. TY

 

To throw more variables to the equation:
At moderate temps, ECO mode and coolant temp also control ICE triggering for heat?
It's about 20 C (68 F) this evening, display shows 21 C.
Car was driven on EV mode only today, 4 km remained on the estimate.
In EV mode and ECO mode tried to trigger the ICE for heating with no success, temp set to fan on (low and high), A/C on and off, Auto, you name it, no ICE and no warm air.
Once I went out of ECO mode (set temp was on 30 C and fan on) Ice came on and with it warm air after several seconds.
My conclusion: in ECO mode and ambient temp 20 C or above you can get warm air only if coolant temp is higher than ambient, ICE is suppressed.
Will try it again when ambient is 18-19 C to find out the lower limit for this.

 

Interesting, maybe Toyota made special cars for the middle East.

 

Or maybe some changes introduced to the 2013?

 

Very possible.

 

eco mode suppreses a/c and heat.

the one under the hood, or the one under the dash?

 

Yup. With the engine using the PLANET power-carriers and the little motor (MG1) connected as the SUN, getting the split to work requires the big motor (MG2) to rotate in the opposite direction when the engine is stopped. And since MG2 is the traction power source for EV, which is what most directly connects to the wheels, that means MG1 must rotate in a negative (backward) direction... hence the -RPM value. Then when the engine fires up, they all start operating with a complex interplay. That's why you see varying RPM of each. They seek out efficiency opportunities, even when quite brief.

This animation I created illustrates the EV operation:



Notice how the planets (engine power-carriers) are rotating even though the ring they are on is not.

 

I prefer: modifies the way a/c and heat operate.

 

unlike

 

My housemate starts the engine at the beginning of her ~22 mile commute. She then does one of two things with EV mode: either she starts using it when the car is completely warm inside, on a 40MPH stretch of road that becomes a 30MPH stretch in two cities, before going back to 55 (back to Hybrid mode, then), or, alternatively, she uses Hybrid mode for the whole, slightly more uphill drive in, then uses up most or all of EV mode on the drive home (again, after warming it up in Hybrid). Yesterday, she did the latter and got 58MPG on the drive in, and 102 on the drive home. 80MPG overall average in cold November weather.

 

Not true about air flow direction (at least not in my car). In fact, it would be much less effective this way, Toyota is not stupid.

 

i'm cool with that.

 

Need gloves? A new hat? New boots maybe?

 

shorts, no socks.

 

yeah well they frown on that where she works in Boston
Just got worse - first snow just hit ! Snow before TurkeyDay is just wrong

 

I know I'm nitpicking, but that'd be 74 MPG. MPG isn't linear, makes for funky math.

 

Today I cold soaked at 19 degrees for 5 hours. EV worked perfect when I drove, no ICE start.

XT1060 ?

 

How does that work?

 

Well, it's a derived measurement:
22/58 = .379 gallons
22/102 = .216 gallons
total 44 miles/ .595 gallons = 74 MPG

or, to go with a different example, simpler numbers:
100 mi/1 gallon = 100 MPG
100 mi/2 gallon = 50 MPG

200 mi/3 gallons = 67 MPG taking the individual values and totaling them
(100 MPG +50 MPG)/2 = 75, so simply averaging MPG doesn't work.

I'm no mathematician (and I don't know what terms actually applies to this), but to get the total MPG, it'd be (M1 + M2)/(G1 + G2), and if what you have is M1/G1 and M2/G2, I don't think math will get you there with the derived values only unless G1 = G2.

 

Thanks. Does the car use a similar algorithm when it calculates MPG?