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When buying a T8 in the Netherlands, you get a complementary drivers’ training to use the hybrid possibilities in an optimal way. Last week I was invited to participate.

The invitation had some curious part. We were asked to participate the training with a fully loaded battery. It was described in detail how to switch the T8 to save mode, with help of the rotary switch, including some illustrations to explain it. I do hope every XC90 driver/owner knows that already ;)

It’s not a classical event but a pure 1-to-1 training, or in this case 1-to-2 because my wife was participating as well while she’s a regular driver too. Volvo NL is hiring a special agency for these events, who also organise these trainings for other hybrid cars like VW (Golf / Passat) and MB (C-class and GLE to come).

The guy started to explain in detail al the technical issues of the hybrid topology of the T8. I’m sure you are all aware about, but still it’s interesting to hear. He started to explain Volvo had short trips in mind when designing the T8 in first place. When driving large distances regularly the D5 - please note this is Europe - would fit better.
Secondly the explanation of the AWD/Off road mode was very interesting. It’s designed in such a way the T8 has the same performance compared to the other Haldex equipped XC90’s. Although the high power alternator (SIG) can’t deliver full power to the electro motor, that’s only possible with charged batteries, it’s still enough to deliver full torque.

The training itself is focussing on getting the best possible fuel consumption. It’s not only a question of charging the batteries regularly, but also using the drive modes and the drive line optimally. First of all, it’s important to know the e-driveline works best up to 50 mph (80 km/h). Driving above that on the electromotor is not wise simply because it discharge the battery quickly. It’s therefore recommended to switch-over to save-mode and switch back again when the vehicle speed is clearly below the 50 mph (80 km/h). In save mode, try to use the cruise control as much as possible.

Secondly it’s important to keep the vehicle rolling. Acceleration, especially from standing still, cost a lot of energy especially with this 5050 lbs (2300 kg) vehicle. Therefore try to keep (some) speed in the vehicle by anticipating on traffic situation. Is the traffic light red? Try to keep the vehicle rolling and avoid to brake.
The T8 can support this by selecting ‘D’ with the gear shift, instead of ‘B’. By selecting ‘D’ the vehicle rolls very easily. Although ‘B; regenerates (much more) energy compared to ‘D’, the basis thought is to roll as much as possible instead of braking. Saving energy is better than storing it. According to the trainer ‘B’ is only used/needed in the mountains.

After all the theory we went to the car to try this ourselves in practice. Because the training was organised at the dealership, close to where we live, it was more or less a practice through our own neighbourhood.
First of all, when you practice a little you can already gain a lot by anticipating and let the vehicle roll instead of giving ‘gas’. It’s really unbelievable how good the T8 rolls and keep speed in ‘D’. You can release the pedal quite early and let roll the vehicle without annoying the other traffic.

Because we drove a route, we’ve driven before we could compare the result. It was a combination of urban traffic, main road (50 mph/ 80 kmh) and some highway (80 mph / 130 kmh). Normally, the app is reporting about 58 mpg (4,0 l/100km) but know it’s a stunning 78 mpg (3.4 l/100km).
Of course this is only a certain route. In daily traffic, in total 2500 m (4000 km) we’ve an average of 47 mpg (5,5 l/100 km). Interesting to see if we can reduce this.

The total training was about 1,5 hour and I can recommended such an event to each hybrid driver.
 

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Cool! Wasn't told about such training here in Canada lol But would be cool to learn about it.
 

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Thanks for the report. Other than driving back from the dealer, I always have a charge, so I am not sure what gasoline mpg I would get.
If the battery is depleted is the initial acceleration impaired?
 

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Am I correct then in assuming that, at highway speeds the recommendation is Save, as opposed to Hybrid?
 

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Thanks for sharing! Much of this sounds applicable to any type of drive train (anticipate traffic, keep steady speed, avoid braking, etc.), but it is interesting to hear the T8's design philosophy and particularly interesting to hear about how the AWD can still work without a fully charged battery.
 

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From the Volvo support site:
"The rear wheels in the T8 are powered using the electric motor. Your XC90 is equipped with a powerful engine driven generator called an Integrated Starter Generator (ISG). The ISG provides electric power on demand, meaning AWD is always available regardless of the battery's available power."
 
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