Which car is the best choice for the climate, and which one for the air quality?

On the eve of the Brussels Motor Show, the VRT news desk carried out research into the impact the different car engine types have on our planet. This research yielded some surprising results. 

The VRT science news room compared five different engine types: an electric car with rechargeable batteries, a car running on hydrogen, one powered by diesel, and also vehicles using petrol and CNG (compressed natural gas).

To determine the impact on our planet, they took into account all factors: from the making of the car (the use of raw materials) to the combustion itself, the manufacturing of the fuel and the recycling. All cars were deemed to be more or less of the same size, though they took into account that in general, electric cars have a bigger weight due to the big battery.

This being said, it was reported recently that more Belgians are now preferring a big SUV when purchasing a new car on fossil fuels like CNG, petrol or diesel, which puts the difference in perspective. 

1. Air quality: diesel not doing too bad

First, they focused on particulate matter and nitrogen oxide (NO) to measure the impact on air quality. It turs out that the modern diesel cars (i.e. those bearing the Euro 6 label, maximum about 4 years old) are not doing too bad. As to the three cars powered by fossil fuels, diesel performed better for particulate matter than CNG and petrol. 

Nitrogen oxides are no longer a major problem for modern cars using fossil fuels, thanks to new technologies, different experts told the VRT. This being said, electric cars rule, provided that they run on green electricity, powered by solar panels or wind turbines. 

The conclusion is that an electric car is the best choice, followed by hydrogen. However, the difference with vehicles running on fossil fuels, is relatively small now, thanks to the latest technologies. Expert Maarten Messagie: "The real fight concerns the climate now."

Thanks to the latest technologies, recent cars on fossil fuels are closing the gap with electricity and CNG: the differences are small where air quality is concerned

2. Climate: electric cars rule, CNG disappoints

For the impact on the climate, the VRT looked into greenhouse gas emissions such as CO2 and methane. In this test, the (negative) surprise was the CNG car, because of methane leaks during the manfacturing of the fuel. Methane is a far more aggressive greenhouse gas than CO2 (up to 28 times as harmful) though it doesn't stay as long on the atmosphere. 

"The government made the choice to stimulate CNG cars and this was a wrong choice where the climate is concerned", the VRT's Luc Pauwels says. However, the Flemish government recently also decided to scrap tax benefits for electric cars, which caused a stir among environmentalists.

Indeed, the electric cars win the climate battle as well. Hydrogen is on number 2, while the fossil fuels are a long way behind. Diesel takes third place, followed petrol and CNG. 

Vehicles using fossil fuels like diesel, petrol or CNG are a long way behind electric cars where the impact on the climate is concerned

3. The final conclusion: go electric!

Overall, the electric car comes out on top when we take into account both the air quality and the climate. Cars running on fossil fuels have fewer harmful emissions for our health (if they are modern and new) than in the past, but are always a worse choice for the climate. Your best choice for the planet would be an electric car or one running on hydrogen, but make sure the electricity you are using is 100 percent green (and that it does not come from German coal plants, for example).