To drive an emission-free car, the only option is to buy an electric car or a hydrogen car that simply expels water vapour into the atmosphere. All other cars emit a variety of harmful gases, including the dreaded carbon dioxide (CO2), which is not a pollutant but is a greenhouse gas and a cause of global warming.

In many European countries, low-emission cars have tax advantages, both in terms of purchase and annual taxes, which means that going green is rewarded, although it is also true that it is a high cost to take home vehicles with advanced propulsion systems.

The cars with the lowest CO2

We have decided to provide you with an up-to-date buying guide of the cars sold in Europe that emit the least CO2, i.e. those that pay the least tax overall (excluding electrics and fuel cells). Worth noting is the fact that these are all plug-in hybrid cars, which have a clear advantage over the WLTP type-approval cycle in terms of the amount of CO2 emitted because the tests are carried out starting with the battery charged and therefore much of the driving is done with the combustion engine switched off.

  1. Mercedes-Benz GLC - 10 g/km
  2. Toyota Prius - 11 g/km
  3. Mercedes-Benz C-Class - 11 g/km
  4. Mercedes-Benz E-Class - 12 g/km
  5. Mercedes-Benz S-Class - 13 g/km
  6. BMW X1 - 16 g/km
  7. Range Rover - 16 g/km
  8. Range Rover Sport - 16 g/km
  9. Volvo S60 - 16 g/km
  10. Mercedes-Benz GLE - 15 g/km

Mercedes-Benz GLC - 10 g/km

The GLC is the king of this special ranking with a record of just 10 g/km, set in particular by the 4MATIC Plug-in Hybrid 300 version, powered by a 2.0-litre turbodiesel block with 194 bhp plus a 134 bhp electric motor. In total, that's 328 bhp. 

Mercedes-Benz GLC 2022

Mercedes-Benz GLC

CO2 levels remain identical for the Coupé version, while they increase slightly for the GLC 300 e 4MATIC (335 bhp) and GLC 400 e 4MATIC (383 bhp) petrol plug-in hybrids, which register 12 g/km. All of these GLCs are equipped with a 31.2 kWh battery that enables an electric range of up to 80 miles (130 km).

Toyota Prius Plug-in: 11 g/km

Close behind the German champion is the new Toyota Prius Plug-in, which in the basic Active version with 17-inch wheels has a certified carbon dioxide emission of 11 g/km. The other versions with 19-inch wheels go up to 16 g/km.

Toyota Prius Plug-in Hybrid

Toyota Prius Plug-in

The powertrain consists of a 2.0-litre naturally aspirated 149 bhp engine plus a 161 bhp electric motor, giving a combined 220 bhp. The 13.6 kWh battery promises an electric range of up to 53 miles (86 km).

Mercedes-Benz C-Class: 11 g/km

Thanks to its numerous plug-in hybrid systems, Mercedes-Benz confirms its position in this low CO emissions ranking, placing the C-Class in third place, tied with the Prius.

Mercedes-Benz Clase C 2021

Mercedes-Benz C-Class

Specifically, it is the rear-wheel-drive C 300 Plug-in Hybrid saloon that achieves 11 g/km. Its PHEV powertrain, with turbodiesel engine reaches 321 bhp (194+127 bhp). Emissions increase slightly with the 4MATIC system or Estate body (12 g/km). The petrol options C 300 e (328 bhp) and C 400 e 4MATIC (375 bhp) report 12 and 14 g/km respectively. In total, the 25.4 kWh battery offers a 'clean' range of 72 miles (116 km) maximum.

Mercedes-Benz E-Class: 12 g/km

The brand new E-Class, despite its size, enters this ranking thanks to the 12 g/km plug-in hybrid powertrain of the E 300 Plug-in Hybrid and E 300 e Plug-in Hybrid version. The former is diesel and delivers 322 bhp, while the latter is petrol-powered and develops 328 bhp. 

Mercedes-Benz Clase E 2023

Mercedes-Benz E-Class

CO2 emissions rise to 14 g/km in the 4MATIC all-wheel drive versions and the same applies to the 375 bhp C 400 e Plug-in Hybrid variant. The E Estate (estate body) scores 13 g/km in the E 300 Plug-in Hybrid. The 25.4 kWh battery offers an electric range of up to 73 miles (117 km).

Mercedes-Benz S-Class: 13 g/km

A true giant of the road surprises in this ranking, but enters on its own merits. The S-Class 580 e Plug-in Hybrid is rated at just 13 g/km.

Mercedes-Benz Clase S 2020

Mercedes-Benz S-Class

The 5.17-metre-long flagship achieves this result thanks to the 362 bhp 3.0-litre inline six-cylinder petrol engine plus the 148 bhp electric motor unit, which generates a combined 510 bhp. The 4MATIC version gets up to 15 g/km, while the 28.6 kWh battery enables it to drive up to 73 miles (117 km) on electric power.

BMW X1: 16 g/km

There's also a BMW on this list of 'green' cars, it's the 16 g/km X1. The figure is achieved by both the xDrive25e, with 242 bhp, and the xDrive30e, with 322 bhp. 

BMW X1 2022

BMW X1

The compact SUV's two PHEVs use the company's 1.5-litre three-cylinder engine, plus an electric unit that drives the rear axle, so the car enjoys all-wheel drive. The associated Steptronico seven-speed dual-clutch transmission is used, while the 16.3 kWh battery provides an electric range of 53 miles (86 km).

Range Rover: 16 g/km

There's another road-going giant on this list, but this time it's also suitable for off-road driving. It's the Range Rover which, with the P460e SE version, records 16 g/km of CO2 on the WLTP type-approval cycle.

Land Rover Range Rover (2022)

Range Rover

This is a huge off-roader just over 5 metres long and over 2.7 tonnes with a 3.0-litre twin-turbo petrol engine supported by an electric unit. The total power output is 453 bhp and a 31.8 kW battery is integrated into, which generates an electric range of up to 74 miles (119 km).

Range Rover Sport: 16 g/km

The Range Rover's smaller (but not too small) sibling is the Range Rover Sport, which with its P460e SE version also achieves 16 g/km CO2.

Range Rover Sport 2022

Range Rover Sport

The powertrain is exactly the same, as is the battery, but in this case, 75 mile (121 km) range in EV mode is homologated.

Volvo S60: 16 g/km

The only Swedish representative in this ranking is the Volvo S60 and, in particular, the T8 Recharge Plug-in Hybrid AWD, which cuts CO2 emissions by 16 g/km.

Nuova Volvo S60

Volvo S60

The saloon uses a 306 bhp 2.0-litre turbo petrol engine, supported by a 143 bhp electric powertrain, developing a total of 449 bhp. The 18.8 kWh battery ensures an electric range of 57 miles (91 km).

Mercedes-Benz GLE: 17 g/km

The last model in the ranking is the Mercedes-Benz GLE which, in particular with the 350 version of the 4MATIC Plug-in Hybrid Coupé achieves 17 g/km CO2.

Mercedes-Benz GLE Coupé 2023

Mercedes-Benz GLE Coupé

The excellent result of the large German SUV is largely due to the 31.2 kWh battery that offers an electric range of up to 65 miles (105 km). Then there's the 328 bhp powertrain, with a 194 bhp 2.0-litre diesel engine plus the 134 bhp electric unit. The 31.2 kWh battery provides 68 miles (109 km) 'green'. 

The plug-in version with standard bodywork goes up to 18 g/km, while the petrol variant GLE 400 e 4MATIC Coupé achieves 19 g/km.