Toyota Auris HSD - Best way to drive a hybrid on Dual Carriageways

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Thu 13 Aug 2015 16:56
Toyota Auris HSD - Best way to drive a hybrid on Dual Carriageways - MarcusC

I've got an Auris HSD and almost all my commute to and from work involves driving on several sections of dual carriageways so accelerating to 50 or 70mph then slowing down to/stopping at a roundabout then accelerating again.

I'm currently averaging around 51mpg (according to on-board computer).

I know this sort of driving probably isn't a hybrid's/CVT gearbox’s strongest point.

Is there any recommended method of driving to maximise fuel economy without holding up the traffic?
I tend to accelerate about half-way into the ‘power’ range (on the dial) until I get about 10mph below the speed limit and then ease off and (if there’s enough room before the next roundabout) slowly increase up to the speed limit.

Would it be better to accelerate as slowly as traffic allows over a longer distance (meaning I might not get to the speed limit before I need to start slowing down for the next roundabout) or accelerate briskly to the speed limit over a short space of time (perhaps even put the car into PWR mode) and coast to the next roundabout (switching to ECO mode if I used PWR mode)?

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Thu 13 Aug 2015 17:20
Toyota Auris HSD - Best way to drive a hybrid on Dual Carriageways - RobJP

Don't overthink it. Just drive.

A few (OK, quite a few) years ago, I did the IAM Advanced Driving course and became a member. It teaches you a great deal about how to anticipate road conditions, how to position yourself on the road so that your visibility is improved (meaning that you see what's happening well before you get there), and suchlike. By doing things like that, you know whether to be accelerating, coasting, etc before you even get there.

Remember, most of the time, brakes are you, wasting money. You've burnt fuel to get up to speed, and now you are wasting all that energy.

All the modes for cars are, in my opinion, a bit of a joke. I've got a BMW 325d. It has Ecopro, which deadens the throttle response, and is horrible. It has Comfort, which the car sits in 99% of the time. It has Sport, and if I want the whole lot available for an overtake, I flick it into that. When I got the car I experimented for a couple of months with the various modes, keeping it in them for a tankful each time. Ecopro (aka Ecopoo) was actually the worst of the lot, mainly because you had to put your foot to the floor to get the car to accelerate properly.

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Thu 13 Aug 2015 19:33
Toyota Auris HSD - Best way to drive a hybrid on Dual Carriageways - 72 dudes

As another IAM member, I agree with most of what RobJP says.

Any acceleration uses fuel, so the best way to drive economically is to accelerate fairly briskly up to your chosen speed, then feather off until you are hardly touching the throttle, to maintain that cruising speed.

If you google (I think) "hypermile" and "pulse and coast" you will find a whole load of US nutters, sorry enthusiasts, who discuss the best way to maximise 'gas mileage' in a Prius.

I would have thought 60 MPG should be achievable in your car/journey.

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Fri 14 Aug 2015 00:09
Toyota Auris HSD - Best way to drive a hybrid on Dual Carriageways - BMW Enthusiast
I have a 2015 Yaris hybrid and the best way to get excellent fuel economy on dual carriageways is to accelerate smoothly up to your desired speed. Sticking to 60MPH will vastly improve your fuel economy. I always stick to 56MPH (90KMH) always use the cruise control and when approaching a roundabout or slowing down disengage it well in advance by the steering wheel control and not the brake pedal. Just let the car coast along then brake nice and smoothly to a stop and if the roundabout is clear don't floor it. This is totally unnecessary. Also don't worry about holding up traffic. A speed limit is not a target. I am averaging 73MPG in my Yaris and getting around 550 miles on a tank of petrol!
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Fri 14 Aug 2015 07:52
Toyota Auris HSD - Best way to drive a hybrid on Dual Carriageways - Bolt
I have a 2015 Yaris hybrid and the best way to get excellent fuel economy on dual carriageways is to accelerate smoothly up to your desired speed. Sticking to 60MPH will vastly improve your fuel economy. I always stick to 56MPH (90KMH) always use the cruise control and when approaching a roundabout or slowing down disengage it well in advance by the steering wheel control and not the brake pedal. Just let the car coast along then brake nice and smoothly to a stop and if the roundabout is clear don't floor it. This is totally unnecessary. Also don't worry about holding up traffic. A speed limit is not a target. I am averaging 73MPG in my Yaris and getting around 550 miles on a tank of petrol!

I think I will stick to Diesel, it used to be very old men and vintage cars that held traffic up building up to speed limit, its now hybrids with drivers afraid to put their foot down with no concern for those behind them and very little difference in fuel economy

68 plus to the tank is good on 36 litre tank but to drive like a snail to get it is going to get some annoyed drivers behind you, I know I`ve got stuck behind several that almost all never get to speed limit????

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Fri 14 Aug 2015 00:55
Toyota Auris HSD - Best way to drive a hybrid on Dual Carriageways - Avant

Very interesting thread - thank you Marcus for starting it.

In many ways I like the idea of a hybrid. My first reaction is that - even though your commute isn't a hybrid's natural territory - you're getting diesel economy without diesel noise/vibration/harshness. And there's the potential for even greater economy if, like AutoSteve, you drive specifically with that in mind.

Driven sensibly it's of course possible to avoid the screamingly high revs that a hybrid with CVT will produce under acceleration. My problem is that - even at nearly 67 - I do enjoy the 'shove' that my Octavia vRS gives when it's needed, such as joining a motorway or dual carriageway: and if I can do so without causing someone else to slow down in my favour, so much the better, and safer.

Of course the best advice has to be Rob's, put with beautiful succinctness, 'Don't overthink it - just drive'. That probably means something between the two opposites suggested in your last para, Marcus. But I can't see anything wrong with judicious use of the PWR mode on a Toyota hybrid to get you up to speed.

I think I must try a hybrid again - probably an Auris estate. Not much liked by the magazine road testers but people who have them seem to love them.

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Fri 14 Aug 2015 09:27
Toyota Auris HSD - Best way to drive a hybrid on Dual Carriageways - kiss (keep it simple)

I don't know much about specific hybrid modes but my understanding is that with regenerative braking you can get quite a bit of your kinetic energy put back into the battery, ready for the next burst of acceleration. Where hybrids lose their advantage is at constant speed, in which case keeping that speed down a bit will have the greatest effect on economy.

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Fri 14 Aug 2015 10:11
Toyota Auris HSD - Best way to drive a hybrid on Dual Carriageways - craig-pd130

I don't know much about specific hybrid modes but my understanding is that with regenerative braking you can get quite a bit of your kinetic energy put back into the battery, ready for the next burst of acceleration. Where hybrids lose their advantage is at constant speed, in which case keeping that speed down a bit will have the greatest effect on economy.

It did cross my mind that, with a hybrid's regen braking, it might be MORE economical over a journey to floor it exiting a roundabout until you reach the speed limit on the road, then lift off and let it cruise, then decelerate without using the brakes to the next roundabout :-D

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Fri 14 Aug 2015 10:57
Toyota Auris HSD - Best way to drive a hybrid on Dual Carriageways - puckdrop

I've got a 1.5 Prius, and I've put 100,000 miles on the clock since I got it ( now at 190k ), and this is an interesting question, and can get quite complicated and anal working stuff out if you really wanted to !

Basically - get the car up to speed as quickly as possible, then lift off the accelerator totally for a second - before then finding the sweet spot on the accelerator to maintain your speed.

I think of the accelerator as a power request, rather than fuel request. If you keep the accelerator absolutely still, you're requesting x amount of power from the _car_. It then choses the best combination for emissions (not economy, although they go hand in hand). If you keep your pedal exactly still, you will slow down (and reduce mpg) going up, and speed up (and increase mpg) going down hill.

Slowing for a roundabout from 6 miles out is not a good idea.

1) It hacks people off.

2) It's boring.

3) The pub will be shut by the time you get there.

Best way is to feel for the point at which you are braking too much for the car to cope with the electricity being generated (at which point it uses the friction brakes). The friction brakes definitely come on below 7mph - below this there is no braking effort from the regen so you'd never stop - hence the need for old stuff.

The faster you are going, the more energy is available to be captured and put into the battery - therefore you'll find the harder you brake, the more chance there is of wasting that energy.

It's all about finding the balance, reading the road ahead etc..

FWIW, I usually average about 62+mpg from a tank (45L) in the summer - usually a tank range of 580 - 650 miles. A mixture of "hypermiling" and just generally driving normal/fast ( eg. 70+ on my M1 commute ).

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Fri 14 Aug 2015 11:00
Toyota Auris HSD - Best way to drive a hybrid on Dual Carriageways - MarcusC

Thanks for all your replies so far.

I was driving in ECO mode all the time but I have now switched that off and will see what difference that makes along with accellerating slightly more briskly (as I would in a normal car).

I do wonder about the efficiency of CVT gearboxes as brisk accelleration & going up steep hills does tend to make the revs go a lot higher compared to a conventional manual gearbox (as I was reminded of when I was using a loan car when mine was recently in the garage having an alarm fault repaired).
It seems that to go up a very steep hill requires the accellerator to be pushed almost to the floor and the engine revs sent so high that anyone living nearby is probably thinking "bloomin boy racers tearing up that hill again" when in reality you're struggling to get above 20mph!
Maybe it's just Toyota's CVT gearboxes?

What sort of gearboxes do other hybrids use?
Do they suffer from the same issue?
Are there hybrids with paddle-shift gearboxes? (this would seem like the best compromise as long as the car can override and make gear changes itself if the engine/motor drops below or rises above certian limits)

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Fri 14 Aug 2015 11:14
Toyota Auris HSD - Best way to drive a hybrid on Dual Carriageways - nortones2

What model year is your Auris? Reason for asking is that having recently test driven a 2015 year facelift, and before that the similar 2014, I drove up towards Buxton from Macclesfield, as a deliberate try-out of the e-CVT transmission. Yes, it allowed revs to rise when foot flat to the floor, but at that stage we were moving pretty quickly! Modulating the throttle gave quite brisk acceleration even on the steep slopes in that area. The more recent versions seem to have had the software tweeked to give a more linear response. The OP could ask Toyota Owners Club their views. BTW; the Toyota hybrid "CVT" isn't a CVT in the Daf sense, although many motoring journalists imagine they are hearing the grinding of drive belts as they floor the throttle......

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Fri 14 Aug 2015 11:17
Toyota Auris HSD - Best way to drive a hybrid on Dual Carriageways - puckdrop

Other half has a Jazz Hybrid which uses the Honda IMA system (basically an electric motor between the engine and a CVT gearbox).

It's a very weak motor compared to the HSD system, and the engine always has to be turning - whereas the HSD system can be "engine stopped" below 43mph

Your issue with the revs isn't a hybrid issue really - it's a CVT gearbox characteristic.

The idea is that it keeps the engine at optimal revs for the demands placed on it - lots of smaller cars such as the corsa, fiesta etc. use or used CVT. Have a look on Wikipedia.

The HSD system is slightly different - it's a CVT in principal but totally mechanically different - one of the two electric motors (MG1) acts as the CVT by changing direction and speed - therefore changing the effective gear ratio between the engine and the wheels. The ratio of MG2 ( the "EV" motor ) is effectively fixed.

Remember, the HSD's main aim is emissions - toyota will have an "engine" map somewhere which says at X1 rpm with Y1 load, emissions are good. So it runs the engine at x1 RPM for the load. This might not be enough to give you what you want, so it uses the electric motor to add to this power. When the battery runs down, it switches to x2 RPM - and is now making too much power (but efficient emissions) - and so uses that excess power to charge the battery. When the battery has enough charge, it goes back down to x1rpm and uses the battery again.

It really does seem strange sometimes to be going up a steep hill, and see two scenarious - one where everything is being chucked at moving the car - high revs AND battery power, and the other one just below that level where you are going up a hill at high revs but also charging the battery !

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Fri 14 Aug 2015 11:24
Toyota Auris HSD - Best way to drive a hybrid on Dual Carriageways - pork_pie

Funnily enough I own the HSD Touring Sports and yes its slated by the press but I absolutely love the car.

I dont bother with the "ECO" mode as it blunts almost everything. I just use the default mode with "PWR" only used in hilly areas.

A journey example is froM West Wirral to Altrincham via the M56 and anticipation of the road is important and use engine braking to recharge the battery which will be required for part of the journey where speeds are no more than 40mph.

On the motorway just keep the acceleration controlled and keep an eye on the energy needle so that it does not go into "Power" territory all the time. Also select instant consumption on your computer to monitor your fuel use.

I keep my speeds around 60-65 mph and I find it a superb cruiser on the motorway and the isntant MPG is simmering around 55-60mpg

I have done under 4000 miles in this car and I average 57mpg (actual not computer)

On urban trips alone I can do 70/80mpg according to the computer although in reality its 90% of that. Hybrids are good if your driving style matches - they are not for everyone.

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Fri 14 Aug 2015 13:10
Toyota Auris HSD - Best way to drive a hybrid on Dual Carriageways - kiss (keep it simple)

One reason that the car needs load of revs when accelerating is because the engine uses the Atkinson cycle. It is more efficient but at the expense of low speed torque.

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Fri 14 Aug 2015 15:08
Toyota Auris HSD - Best way to drive a hybrid on Dual Carriageways - nortones2

The batteries fill the torque hole. And there is really no need for loads of revs. As I said earlier, the thottle can be modulated to balance noise against thrust. For maximum power, as with conventional engines, full power revs are needed. Even at full revs, which I think is around 4500rpm, the noise is not great. SPL measurements might help!

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Fri 14 Aug 2015 21:26
Toyota Auris HSD - Best way to drive a hybrid on Dual Carriageways - Auristocrat

See: blog.toyota.co.uk/hybrid-driving-technique-toyotas...d

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