Plug-in hybrid cars are harmful to the planet, this study proves it once again

A study carried out by the NGO Transport & Environment denounces the CO2 emissions of plug-in hybrid cars, much higher than those announced by the manufacturers. For the organization, this motorization should not be promoted or subsidized in any way by public authorities.

Mercedes-Maybach S 580 e hybride rechargeable

While electric car sales have risen sharply over the years, especially in France, they still have a hard time convincing some motorists. In fact, there are many who will be held back by the price, but especially by the autonomy. So much so that most would like to have a car that exceeds 400 kilometers. An erroneous reasoning as we explained a little before. This is one of the reasons why some drivers prefer to opt for plug-in hybrid models, which are considered more versatile.

A life-size test

This engine, of which however, market share fell slightly in France between 2021 and 2022 according to CCFA figures, then it combines a classic thermal block with an electric motor. It is therefore possible to drive only with the latter, as long as the battery is charged. And that is the problem. Because as the NGO explains Transport and Environmentmost plug-in hybrids, especially those in business fleets, never recharge.

We had also returned to this problem in great detail in a previous file on the subject.

However, this poses a real problem. To demonstrate this, the organization tested three plug-in hybrid (PHEV) cars from the same segment, namely a Peugeot 308, a BMW 3 Series and a Renault Mégane. And the results are catastrophic. In fact, with an empty battery, the first two refused approximately 200 grams of CO2 per kilometer, against “only” 138g/km of the last one. It has a more powerful electric motor and above all shows a lighter weight.

The problem of unreal autonomy

For comparison, all three models advertise emissions of 27, 36 and 30 grams of CO2 per kilometer respectively. Suffice it to say that the difference is huge. You may think that plugging in your car will fix the problem. However, according to Transport & Environment tests, the first two cars never reach the fully electric range announced according to the WLTP cycle. The 308 reaches 56% of official autonomy, when the BMW rises to 74%. Here again, only the Mégane keeps its promises, with an announced autonomy of 48 kilometers that rises to 49 km in practice.

Only one in three cars managed to reach the official figure. To arrive at these results, several experiments were carried out in different urban and peri-urban routes in Graz, in Austria. Thus, if we already know that hybrid cars are not designed for the road, while their electric range melts very quickly and their consumption increases, they are not ideal for the city either.

An advantage for brands

In fact, the NGO was also able to prove the technology the geo-fencing of the BMW 3 Series. This allows the car to know when you are driving in the city, to use only the electric motor. A particularly suitable system for our French ZFEs, especially during pollution peaks. However, the experiment turned out to be disastrous: the thermal block has taken over several times.

In addition, outside these zones, the internal combustion engine recharges the battery by spinning faster, increasing fuel consumption and CO2 emissions by 50% compared to the WLTP cycle according to the detailed report. Overall, these tests showed that the 3 Series polluted three times more than advertised, while the 308 and Mégane emitted between 20 and 70% more, over a relatively short 55-kilometre run.

But then, why do brands continue to sell this type of engine considered so harmful to the environment? According to the NGO, the commercialization of cars that show, even virtually, low emissions allows manufacturers to have less pressure to sell electric models, which saves them time. In fact, the CAFE regulations implemented in 2021 simply impose a CO2 emissions threshold that must not be exceeded for each brand. She’s free to do whatever she wants to stay down, even if it means selling more polluting cars than advertised, like plug-in hybrids.

What solutions?

Therefore, Transport & Environment urges public authorities to act, pending the modification of the WLTP cycle in 2027, which will better reflect the actual uses of PHEV vehicles. Thus, the organization issues some recommendations, such as the end of financial aid, or at least a limitation according to certain parameters such as emissions or electric autonomy.

It already worked like this in France before the ecological bonus for plug-in hybrids was removed. For the NGO, the sanction should also be based on actual CO2 emissions and not on those announced.

The NGO also recommends that these be regularly updated with data of real conditions of use and that manufacturers eliminate the possibility of recharging the battery with the internal combustion engine. Finally, the latter should better educate their customers and encourage them to drive electric by rewarding them.

Some manufacturers, such as Peugeot, Citroën and DS, in particular, have installed a visual reminder on the dashboard to encourage the driver to recharge their car. For its part, BMW has launched a distance-based reward system toured by owners in 100% electric mode. Be that as it may, and if PHEVs are in danger, motorists are strongly opposed to the disappearance of this motorization.