ElliotB

What FE are you achieving?

chromedome

I'm gonna bring this thread back from the dead because I'm interested in the same thing - does anyone here use hypermiling techniques in the ES300h? I've heard of the pulse glide technique for the Prius - accelerate moderately under ICE power to a bit above your target speed, then release and then apply a tiny bit of throttle to get the car to freewheel without engaging motor regen or using battery assist.

I can't get this to work at all on the ES at slow speeds (below 60 km/h). The moment I let go of the accelerator, the car slows down and motor regen kicks in to recharge the battery. If I apply a tiny bit of throttle, the battery pack supplies power to the motor to turn the wheels. If the battery charge is low, the engine kicks in. This happens in Eco, Normal and Sport modes. I end up using mild acceleration and looking a long ways ahead to maximize my coasting for more fuel efficiency.

atoyota

I used to participate in the hypermile forums and priuschat when I had my previous Toyota hybrids. Because the hybrid system in the ES300h seems to go into and stay in pure EV mode much easier than the two Camry hybrids I've had, I haven't found it as necessary to learn how to manipulate the 300h's hybrid system's decisions like I did in those earlier cars. As for other techniques that true hypermilers use independent of hybrid systems such as close-in drafting behind other cars/trucks and driving slower in traffic to avoid stops and starts (and other techniques), I am happy with my over all fuel fil-up average of 39.3 mpg at 23K miles to really want to engage in those behaviors any more. The 39.3 mpg average in my 300h is better than the 37 mpg average I was ever able to attain the Camrys - and I dare say I drive far less conservatively than in the Camrys too.

EDIT: With the above being said, I do use the EV mode button for leaving my garage and for leaving the garage at work. This allows me to avoid engaging the ICE until I am at street speeds of at least 20 MPH or higher - assuming the outside temperatures are moderate enough not to require the ICE to engage to heat up the engine and catalytic converter. Here in southeast TX I enjoy a milder winter than some. Another thing I've noticed is that even with the ventilation/ac system turned off, if I have the climate control previously set higher than the ambient temperature, the ICE will turn on to warm up the system for the heater elements - even though I don't have it turned on. So I set my climate control temperatures to below 70 (lower even sometimes) before I turn off the system and the car seems to go into EV mode a lot quicker in cooler/colder temps.

ElliotB

"I've heard of the pulse glide technique for the Prius - accelerate moderately under ICE power to a bit above your target speed, then release and then apply a tiny bit of throttle to get the car to freewheel without engaging motor regen or using battery assist."

This technique does work if the traction battery has enough charge, and the a/c is off (preferably) and your are driving under 40 mph.

chromedome

I'm not advocating dangerous hypermiling techniques like drafting and going much slower than traffic... It's insane to aim for low fuel consumption while putting your life at risk.

Anyway, I've never gotten pulse glide to work, mainly because I have the heater on most of the time (0C ain't fun) and my battery SOC isn't high on my town commute. I did get warp stealth to work past 60 km/h - accelerate past the target speed, then back off, then feather the throttle lightly so the car runs on battery power and very gradually loses speed. I'll switch to the tach display in Normal mode to get optimum engine revs during the acceleration phase. Supposedly 1800-2200 RPM is the best combo of high power and low fuel use on the Prius; haven't found anything for the Camry Hybrid or the ES but the range should be similar.

I did get 55 mpg once in town driving... I would love to see ridiculous numbers like 70 mpg on a huge car like this.

chromedome

67 mpg or 3.5 l/100 km, I love this car! Pic below.

I went on a 100 km trip to the mountains and back, through rolling hills and rural roads doing 60-80 km/h.

Outbound leg:
5.2 l/100 km or 45 mpg
Outside temp 10C, heater on occasionally
I tried using pulse glide and warp stealth in Normal mode, accelerating uphill and on the pulse phase, feathering on the glide and downhill. Regen rarely kicked in.

Return leg:
3.5 l/100 km or 67 mpg
Outside temp barely above 0C, heater on constantly
I drove using my usual fuel saver style in Normal mode, keeping constant speed on flat ground, accelerating uphill below 2500 rpm, using lots of regen going downhill.

It was a lot less distracting doing my usual thing compared to pulse glide and warp stealth. I didn't move slower than traffic and I didn't rubber-band my speed. Toyota probably modified the hybrid system algorithms on the ES to make it default to the most efficient mode without user tweaking. Atoyota's right, this car could make a street racer look fuel efficient

As for EV mode, my starting SOC is usually too low and current temps require the engine to run to warm up. A plug-in ES with a fat lithium ion pack in the future would be interesting.

chromedome

I've been using pulse and glide for the past two tanks and I'm getting higher fuel consumption than before. I still can't get to that specific point where regen and battery assist cancel out and the car freewheels, even at speeds below 60 km/h and with temperatures above 20C. Maybe Lexus programmed the system to use the traction battery more aggressively than the Prius.

I think I'll switch to monitoring my acceleration and regen coasting in city traffic and using cruise control for anything faster.

PirelliRC

i was able to achieve 39-41 mpg when i drive in ECO mode and glide to stops and keep my eye on the Energy Consumption all the time. But i must say this was getting very tiresome and required too much attention and concentration to get those numbers.

The difference between 35 mpg and 39 mpg is about $4. And frankly $4 is not worth the effort i put in to get those numbers. I am more than happy with 35 mpg driving the way i am comfortable. Given that my Challenger gets 10-12 mpg.

wdlugitch

I use ECO full time, and average 38.2.

zes

I, too, can get mine to go into EV mode most of the time but cannot get it to hypermill other than for extremely short periods. One thing that I have found interesting is that I can use the cruise control to give the equivalent of battery braking quite well.

I have a fairly short exit ramp from the freeway on my commute. I found that if I just got my foot off the gas, I could not slow down fast enough and had to apply brakes. I had to brake hard enough to completely bottom out the needle in the charge range and more, and I felt that I was using the friction pads. Bad thing on a hybrid! So one day had my cruise control on the freeway and instead of just disengaging the cruise and hitting the brakes, I held the cruise lever down (in the set/decelerate) mode through the ramp. I found that the car decelerated quite strongly without me having to brake too aggressively. So I have been trying that technique but don't quite know how to get hard data if using the cruise to slow down the car gives me extra juice in the traction battery relative to just using the brakes. The little bars on the display just aren't accurate enough.

Canesguy

Not doing any of this, am on "sport" all the time and I get 37-42 mpg.

chromedome

Went for a 100 km trip up to the mountains and back, speeds from 60-80 km/h through rolling countryside with few stops or traffic lights, and I got 4.6 l/100 km or about 51 mpg. I didn't bother with pulse and glide, I just set cruise control in Eco mode and enjoyed the scenery

I also inflated my tires (Dunlop SP Sports) to 35 psi cold. This seems to help increase mileage and stop the suspension from thumping. The ride is still firm but it's not crashy on rough surfaces like before.

As for using cruise control for braking, it's possible to do the same thing by monitoring the energy dial. You have to brake inside the top end of the Charge zone, if you brake too hard the needle drops down to the bottom and the friction brakes also get used. I usually do a long coast to get to the right speed for my usual off ramp, traffic permitting of course.

PirelliRC

thats awesome, you are the hypermiling champion.

However while inflating the tires above what is suggested will render you better MPG because they roll with less resistance, i highly doubt that it is smoother than say 32-33 PSI cold. The more you inflate the tires the more road input you will get because the tire flexes less and cannot absorb road imperfection as well.

35 PSI is not a huge difference, but on a hot day it will increase to 39-40 PSI, and that is when your ride will get bumpier.

chromedome

Maybe it depends on the tire compound and sidewall design? I felt the ride was firmer but better controlled with 35 psi cold. The tires got up to 39 psi in the middle of the day and even then, it felt like the tires were absorbing impacts instead of sending those impacts up to the shocks and the car body.

At lower pressures, the ride was smoother on smooth roads but felt crashy on rough roads, like the tires were rubber lumps that couldn't properly absorb impacts. That's the price of having firmer suspension and thin sidewalls, I guess. This car ain't no LX.

zes

So I don't understand the concept of hypermilling. I read the thread again, and if the idea is to freewheel the car at constant speed then is that not impossible? The car has to overcome wind and rolling resistance so it must slow down if it is forced to freewheel, unless of course it is going downhill. Is this not a zero sum game. If one freewheels and loses speed then gas will have to be burned to speed it up again. In that case is it not more efficient to maintain speed with slight ICE or traction motor input?