How can we improve our vehicle fleet, one of the most energy-intensive in Europe?

Three complementary solutions can reduce the energy consumption of our fleet (while reducing CO₂ emissions): promoting fuel-efficient vehicles, reducing the total number of kilometres driven, and improving the way we drive (eco-driving).

Compared to conventional petrol vehicles, hybrid, electric and fuel cell vehicles are more fuel-efficient for comparable classes and uses [→ Q35] and [→ Q36]. Moreover, if the electricity and fuel used in these vehicles are, even partially, from renewable sources, this can reduce CO₂ emissions. Diesel vehicles are 10% more fuel-efficient than petrol vehicles under optimum operating conditions. Naturally, new vehicles are also more fuel-efficient than older models.

However, the type of engine is not everything. The Swiss car fleet is among the most fuel-intensive in Europe, with an average fuel consumption of new vehicles of 6.08 litres per 100 km in 2018... and this despite a considerable 30% drop in vehicle consumption since 1996. However, a high proportion of new vehicles are equipped with engines with excellent fuel efficiency. But this is counteracted by the fact that Swiss motorists are “over-motorised”. They have a weakness for 4x4s, SUVs and other large cars. Austria, with a similar topography and socio-economic level, has an average cubic capacity 12% lower than the Swiss car fleet (1,676 cm³ compared to 1,900 cm³).

By favouring smaller engine sizes and avoiding energy-intensive models, fuel consumption could be significantly reduced. There is no lack of choice, with nearly 1,400 models imported into Switzerland consuming less than 5 litres per 100 km, of which around 300 consume less than 4 litres! Finally, a more ecological way of driving (eco-driving) can reduce consumption by about 10% compared to standard driving. In addition, a slight over-inflation of the tyres brings an additional gain of close to 0.3 litres per 100 kilometres without compromising safety. Other simple measures can further reduce fuel consumption: not driving with winter tyres in summer, avoiding ski and bike carriers, etc.

Two options can also reduce CO₂ emissions, although they do not improve fuel efficiency: firstly, replacing petrol or diesel vehicles with natural gas vehicles, which reduces emissions per vehicle by about 22%. There are already more than 13,500 gas-powered vehicles on Swiss roads, representing 0.2% of our car fleet. The number of gas-powered vehicles is constantly increasing, not least because it is much cheaper to drive on gas than on petrol, since natural gas is partially exempt from the mineral oil tax that applies to all fossil fuels. Natural gas at the pump is between 30% and 50% cheaper than petrol (with the same energy content), which soon compensates for the additional cost of 10% of the vehicle purchase price, a differential which is in any case tending to diminish.

Secondly, increasing the biofuel content (bioethanol, biodiesel, etc.) in traditional liquid fuels or natural gas (biogas). The social and environmental sustainability of such biofuels will have to be guaranteed, in order to avoid as far as possible negative impacts, particularly during their production. So-called “first generation” biofuels (derived from agricultural products) will thus be gradually phased out in favour of new generations (based on micro-algae, agricultural or wood residues, etc.), which have a better social and environmental record, while offering a much greater potential for reducing greenhouse gas emissions.