For a hybrid vehicle, all the energy comes from oil. Less is wasted (because the energy is saved when you brake), but the main advantage is in town, when you don't have to use your heat engine / thermal motor (?).

For a long trip, a hybrid vehicle has no advantage in terms of oil consumption.

But this is what I think : we should give up using heat engine. They are ineffective - but very practical. That is not what is implied by a 70 g/km recommendation : I think they imagine that the cars will still be using conventional motors.

Until now, only heat engine can transform oil into movement.