Active Grille system

[AndyL61]

I thought the active grille was to aid battery cooling ? So would you not think it should be operated by battery temperature not by the AC being on or off ?

 

[tsedge]

I thought the active grille was to aid battery cooling ? So would you not think it should be operated by battery temperature not by the AC being on or off ?

It may well be general cooling airflow that can help either of the two cooling loops in the system.

 

[mg4mc]

Both the battery and AC radiators are behind the grill so it opens if either of them need airflow.

 

[sunbluesky]

The battery gets cooled via a little heat exchanger in the AC circuit so effectively shares the condenser mounted at the front of the car.
If you're stuffing 130kw into it during DC charging I would guess the grill should open and AC be active to protect the battery.
If it also opens when you're just running the HVAC you've got to wonder what the hell is the point of it though (the active vent) as it's hardly ever going to be closed for most folks.

FWIW, I've been running my SE standard with the lower air intake TOTALLY blocked off since Dec last year in a bid to boost aero efficiency.
Difficult to say how much it helps but there's been no complaints from the car. I don't DC charge so the battery coolant temp remains ambient, pump never runs.
Coolant flows in the other circuit when hammering it and using the onboard charger but I've never seen it climb higher than 50 degrees, the rad fan has yet to run so it's obviously happy with the passive cooling so far.

If the fan starts to spool up as the summer months arrive I'll take that as a hint that the system wants more airflow and at least partially uncover the vent slots again, but I wouldn't be surprised if I just don't need to up here in the chilly north. ?

I'm really curious about your experiment with totally blocking the lower air intake. I'm considering doing the same but I live in Australia. I'm wondering how it went with you in summer?

 

[Macadoodle]

I'm really curious about your experiment with totally blocking the lower air intake. I'm considering doing the same but I live in Australia. I'm wondering how it went with you in summer?

Hi there, yes been through 2 highland 'summers'- never above 30 degrees C and closer to 25 at best- but the car has been totally fine, still running it with the vents completely covered.

Really can't say what aero improvements it gives, guessing it must help a little though. I mainly like the fact that it has preserved the coolant rad and air con condenser in a pristine state, no stone impact damage at all.
DC charged a few times on summer road trips now, the battery coolant circulated with the fan running but no charge throttling or warning lights, didn't seem to bother it.

I think she has cooling capacity to spare up here at 57 degrees north but I cant speak for sunny down under

 

[hharzel]

I tried blocking the vent last winter when it was minus 20-30 degrees celsius and all I got was extremely misty windows and no sign of decreased consumption. Haven't bothered with it since.

 

[sunbluesky]

The battery gets cooled via a little heat exchanger in the AC circuit so effectively shares the condenser mounted at the front of the car.
If you're stuffing 130kw into it during DC charging I would guess the grill should open and AC be active to protect the battery.
If it also opens when you're just running the HVAC you've got to wonder what the hell is the point of it though (the active vent) as it's hardly ever going to be closed for most folks.

FWIW, I've been running my SE standard with the lower air intake TOTALLY blocked off since Dec last year in a bid to boost aero efficiency.
Difficult to say how much it helps but there's been no complaints from the car. I don't DC charge so the battery coolant temp remains ambient, pump never runs.
Coolant flows in the other circuit when hammering it and using the onboard charger but I've never seen it climb higher than 50 degrees, the rad fan has yet to run so it's obviously happy with the passive cooling so far.

If the fan starts to spool up as the summer months arrive I'll take that as a hint that the system wants more airflow and at least partially uncover the vent slots again, but I wouldn't be surprised if I just don't need to up here in the chilly north. ?

Hey Macadoodle

Hi there, yes been through 2 highland 'summers'- never above 30 degrees C and closer to 25 at best- but the car has been totally fine, still running it with the vents completely covered.

Really can't say what aero improvements it gives, guessing it must help a little though. I mainly like the fact that it has preserved the coolant rad and air con condenser in a pristine state, no stone impact damage at all.
DC charged a few times on summer road trips now, the battery coolant circulated with the fan running but no charge throttling or warning lights, didn't seem to bother it.

I think she has cooling capacity to spare up here at 57 degrees north but I cant speak for sunny down under

Thanks for that update. By my calculation it should give about a

61.7kWh usable battery gives WLTP 450km = 7.292 km per kWh.
50.8kWh usable battery gives WLTP 350km = 6.889 km per kWh.

Main diffs between the two seems to be the grille.
So if we take the efficiency of the Long Range and apply it to the 51kWh version, then we should get:

50.8kWh x 7.292 = 370.4 km range *

20km more per charge isn't too bad imho.

Given that the WLTP range test includes some slower driving, my guess is that it would be relatively greater for the highway.

What are your thoughts?

 

[Tr380r67]

I have noticed that after the vast majority of my drives in the MG4 Trophy no matter what distance, the active grille has activated. Even on cold days when I wouldn't expect it to do so it has come on. I generally drive it carefully so it's not due to thrashing it. Anyone else noticed it come on more than expected on theirs?

Cheers Michael

We have two MG4 Trophys and the grill opens and a dedicated fan for cooling the battery switches on. When the car is switched off the grill will close and fans switch off at varying times ... But usually within a few seconds. Very rarely does it open in anything but very warm weather.

 

[Macadoodle]

Hey Macadoodle

Thanks for that update. By my calculation it should give about a

61.7kWh usable battery gives WLTP 450km = 7.292 km per kWh.
50.8kWh usable battery gives WLTP 350km = 6.889 km per kWh.

Main diffs between the two seems to be the grille.
So if we take the efficiency of the Long Range and apply it to the 51kWh version, then we should get:

50.8kWh x 7.292 = 370.4 km range *

20km more per charge isn't too bad imho.

Given that the WLTP range test includes some slower driving, my guess is that it would be relatively greater for the highway.

What are your thoughts?

20km or 12 miles would be useful but I really don't think I've noticed that, maybe a few miles were gained but that is difficult to assess within the natural daily variations.

I pulled my front bumper off and cut out some thin plywood to fit neatly behind the vents once I painted it black to match the car, can't be bothered to strip it back out to see if there's an increase in consumption TBH
I mainly pootle around on fairly slow rural roads but someone using faster highways on a daily basis may well see more benefit I think.

 

[mg4mc]

Couldn't you just disconnect the vent motors?

 

[siteguru]

The SR doesn't have active grilles - the vents are always open.

 

[mg4mc]

Doh!