PHEV : Has anyone ever used CHG mode?

[Nick72]

And if so why?

I just realised I never even pressed the  button in 3 years on the last PHEV.

I want to press it on the new one but I don't know why.

Just curious to understand if anyone has found a use case?

For me, the main use case is the one I can't have because we don't get the 1.5kW mains inverter. That is to say, put charge in the traction Battery to power the inverter to power my power tools, a microwave oven, or just my power hungry laptop which is greater than the 150W output we get in the UK from the rear mains plug socket. When I'm out it the styx.

[philip42h]

I've obviously never used CHG mode but I've always understood that it was there to provide additional EV range for use later in a journey. For example, run the car in CHG mode along the motorway so that you can run in pure EV through the city ... 

[Nick72]

35 minutes ago, philip42h said:

I've obviously never used CHG mode but I've always understood that it was there to provide additional EV range for use later in a journey. For example, run the car in CHG mode along the motorway so that you can run in pure EV through the city ... 

Presumably for emissions reasons rather than efficiency, since that would be false economy?

[philip42h]

7 hours ago, Nick72 said:

Presumably for emissions reasons rather than efficiency, since that would be false economy?

Exactly so. Various cities seem to be imposing emissions limits / charges so being able to drive EV only may be advantageous - but I've no idea how they could feasibly govern / manage it since the PHEV will run the ICE when it wants!

[Flatcoat]

Yes i occasionally use it. It affects mpg but I find it useful when driving abroad or very long UK journeys to ensure I have some EV only capacity. 

[ernieb]

Played with it when I got the car but seems very inefficient in operation. Better in my view to switch to HEV mode but that’s from someone who just leaves it in EV mode 95% of the time.

[Cyker]

I wish the Yaris had that button instead of the even more pointless "EV mode" button!

It's mainly so I can force more charge into the Battery before I hit a traffic jam - At the moment the car will end up using up the Battery to crawl through the traffic jam, then run out and run the engine to charge, usually while I'm not moving which is when it's most obnoxious, noisy and vibration..y... , then as soon as traffic starts to move again it *always* stops charging and switches to the electrics again, only to run out just as I stop again and run the engine!

In that specific situation, if I could force it to charge when I'm moving and shut the heck up when I'm sitting still it'd be a lot less annoying!

 

[Nick72]

7 minutes ago, Cyker said:

I wish the Yaris had that button instead of the even more pointless "EV mode" button!

It's mainly so I can force more charge into the battery before I hit a traffic jam - At the moment the car will end up using up the battery to crawl through the traffic jam, then run out and run the engine to charge, usually while I'm not moving which is when it's most obnoxious, noisy and vibration..y... , then as soon as traffic starts to move again it *always* stops charging and switches to the electrics again, only to run out just as I stop again and run the engine!

In that specific situation, if I could force it to charge when I'm moving and shut the heck up when I'm sitting still it'd be a lot less annoying!

 

Got it. So more of a ride comfort and ambience perspective?

[Nick72]

1 hour ago, Flatcoat said:

Yes i occasionally use it. It affects mpg but I find it useful when driving abroad or very long UK journeys to ensure I have some EV only capacity. 

I know what you mean. But surely it's terribly inefficient? 

Must admit that I'll tend to save Battery that's been charged from my wall box for when I'm stuck in jams (efficiency reasons) or driving up and down winding mountain roads as I'm on and off the accelerator (efficiency but also ambience with the roof and windows all open). 

So just for that last ambience part is probably the only reason to press the charge button? That and future city emissions controls that go on to use special cameras to see whether your car is emitting nasty stuff. That's still a way off. Tech exists but it's expensive and very expensive to roll out.

[AJones]

At times when it isn't possible to plug in and the PHEV range is zero, I've used charge mode when making short trips to warm up the engine and charge the Battery on the way out, then doing the return in EV mode, avoiding the need to warm up the engine up twice.

[philip42h]

1 hour ago, Nick72 said:

I know what you mean. But surely it's terribly inefficient? 

... but not a lot more inefficient than just running a self-charging hybrid, since that's all you'd be doing really. 😉

[Nick72]

2 minutes ago, philip42h said:

... but not a lot more inefficient than just running a self-charging hybrid, since that's all you'd be doing really. 😉

I'm not so sure. If that were true then using CHG on the PHEV should still retain an mpg similar to the regular RAV HEV plus or minus a few percent. But it doesn't, it's substantially less. At the end of the day you're working your engine harder than normal to charge a Battery to then drive on the Battery. And, importantly, this is in a non-optimised way versus the algorithms used in normal HEV self-charging operations where a lot of energy is acquired via recuperation processes like regenerative braking.

[philip42h]

1 minute ago, Nick72 said:

I'm not so sure. If that were true then using CHG on the PHEV should still retain an mpg similar to the regular RAV HEV plus or minus a few percent. But it doesn't, it's substantially less. At the end of the day you're working your engine harder than normal to charge a battery to then drive on the battery. And, importantly, this is in a non-optimised way versus the algorithms used in normal HEV self-charging operations where a lot of energy is acquired via recuperation processes like regenerative braking.

Yes, but what you lose on the roundabouts (charging up the battery) you'll get back on the swings (running in pure EV mode - which the HEV nearly never does). It might be a difficult calculation to do since you would need to add back the EV mileage done as a result of recharging the Battery ...

[Oscarmax]

I have used the charge button, fuel consumption drops down to 36-40 mpg as opposed to 50+ mpg in HEV mode.

[Flatcoat]

6 minutes ago, Oscarmax said:

I have used the charge button, fuel consumption drops down to 36-40 mpg as opposed to 50+ mpg in HEV mode.

I get about same. And 36-40mpg is still good for a 2 tonne SUV! 

[Nick72]

33 minutes ago, philip42h said:

Yes, but what you lose on the roundabouts (charging up the battery) you'll get back on the swings (running in pure EV mode - which the HEV nearly never does). It might be a difficult calculation to do since you would need to add back the EV mileage done as a result of recharging the battery ...

You'll never get the losses back.

[Hayzee]

32 minutes ago, Flatcoat said:

I get about same. And 36-40mpg is still good for a 2 tonne SUV! 

In the 10-15 MPG you lose how much EV do you get in return in CHG mode?

[Cyker]

2 hours ago, Nick72 said:

Got it. So more of a ride comfort and ambience perspective?

Yeah - I don't know what it's like in the current RV4s, but in the Yaris the engine is super obnoxious when it's charging the Battery when you are not moving. When it's moving it's surprisingly refined for a 3-cylinder, but it goes full agricultural diesel when all it's doing is charging the Battery while you're stopped!

Also, it's very inefficient when all it's doing is charging the Battery - It's much more efficient when charging the battery AND moving the car at the same time

[Oscarmax]

37 minutes ago, Hayzee said:

In the 10-15 MPG you lose how much EV do you get in return in CHG mode?

We found it charged up surprisingly quick driving solo around the New Forest in Hampshire, we needed a small charge in reserve to tow the caravan back home. I would estimate 1 mile for every 3 miles in charge mode.

36-40 in charge mode is quite efficient, our previous 2020 Mitsubishi Outlander 2.4 PHEV would only manage 36 mpg in HEV when the Battery was depleted.

 

[philip42h]

2 hours ago, Nick72 said:

You'll never get the losses back.

No, of course not - there will be losses and it won't be as efficient as a HEV or running in HV mode.

4 hours ago, Nick72 said:

But surely it's terribly inefficient? 

All I meant is that while it will be inefficient, it won't be terrible ... 😉

[Torrox]

You should try to see if it works. I think it's nice to have it just in case you need some EV miles at the end of your trip.

In May while on the motorway I tested this charge mode to make sure that it works. When confirmed I turned it off.

[Nick72]

8 minutes ago, Torrox said:

You should try to see if it works. I think it's nice to have it just in case you need some EV miles at the end of your trip.

In May while on the motorway I tested this charge mode to make sure that it works. When confirmed I turned it off.

I've got some long road trips coming so I'll give it a go.

[Torrox]

I read that some guy used this mode to warm up the ice before changing oil and charge the hybrid batteries at the same time.

[Oscarmax]

Last year from October until March our journeys are  less then 40 miles, we ran in EV mode most of the time, unfortunately will filled up with E10 at the start of October so had to burn of some fuel every month, we used charge mode.

This year being a little wiser, we leaving the fuel tank with minimal amount of fuel until the spring.

[forkingabout]

32 minutes ago, Torrox said:

I read that some guy used this mode to warm up the ice before changing oil and charge the hybrid batteries at the same time.

You could just activate maintenance mode to force the power unit to run to warm up the engine oil.