Environmentally-friendly cars

Aug 31, 2018

Buying an environmentally-friendly car doesn't mean you have to buy an electric vehicle - although that's not a bad move.

There are dozens of petrol- and diesel-powered models that can rightly claim to be eco-friendly, certainly by the standards of most cars.

These vehicles offer excellent fuel economy, which is good news for your wallet, as well as ensuring reduced emissions of the greenhouse gas carbon dioxide. They also release low levels of toxic nitrogen oxides (NOx) and tiny soot fragments called particulates, which have been linked to early deaths.

Many of the cleanest cars are hybrid vehicles. As well as a petrol or diesel engine, these have batteries and a motor, which can recover energy that's usually lost during braking, and then use it during acceleration, to reduce the demands on the engine and boost fuel economy. Some hybrids are plug-in models, with larger batteries that can be charged up to privide a range of around 20 miles on electric power before the engine is needed.

We've assessed cars based on official fuel economy and emissions figures. These generally understate performance in normal driving. but are the most comprehensive figures available until next year, when emissions of all new cars will be tested in real-world comnditions. 

All cars have official fuel economy figures that are higher 60mpg and CO2 emissions of less than 110g/km. NOx emissions are less than 20mg/km: a third of the current limit for petrol cars and a quarter for diesels. Click below to find the most environmentally-friendly cars in each category, or scroll down to see the full list - as well as advice on buying an environmentally-friendly car.

Most environmentally-friendly cars by category

How to buy an environmentally-friendly car

Is it more environmentally-friendly to keep an old car or buy a new one?

It's often argued that running a car into the ground is the most environmentally option, given the quantity of carbon dioxide emitted during production. A 2011 study funded by the government and transport industry found that a typical family car with a conventional engine will create the equivalent of 24 tons of carbon dioxide by the time it is scrapped, and 5.6 tons are from production.

However, this doesn't take into account the large fuel economy and emissions improvements made by the very latest models. Neither does it account for the higher level of harmful emissions produced by many older cars, which are pumped out into towns and cities.

Are smaller engines more environmentally-friendly?

Environmentally-friendly electric cars

1. Hyundai Ioniq 5.4 miles per kWh

Despite being spacious enough for a family, Hyundai's Ioniq is the most efficient electric car on the market, according to official figures. These reveal that the car uses half as much electricity per mile as the Tesla Model X, reducing the amount of electricity it needs and increasing the range, which - in real world driving - is around 140 miles between charges.
Hyundai Ioniq buying guide

Hyundai Ioniq electric deals

  • 2. Volkswagen e-up! 5.3 miles per kWh
  • 3. Volkswagen e-Golf 4.9 miles per kWh
  • 4. BMW i3 4.9 miles per kWh
  • 5. Smart EQ ForFour 4.8 miles per kWh

Environmentally-friendly plug-in hybrid cars

BMW i3 ReX 470.8mpg

Toyota Prius Plug-in - 283mpg

Hyundai Ioniq PHEV - 256.8mpg

Kia Niro PHEV - 217.3mpg


Environmentally friendly hybrid cars


Toyota Prius - 94.1mpg

Toyota Yaris - 85.6mpg

Toyota Auris 80.7

Lexus CT200h 78.5mpg

Kia Niro 2 hybrid 76.3mpg

Environmentally-friendly petrol cars

Smart ForTwo 71hp - 68.9mpg

Toyota Aygo 1.0 VVT-i - 68.9

Citroen C1 VTi 68 - 68.9mpg

Peugeot 108 1.0i 68 68.9

Environmentally-friendly diesel cars


Renault Clio dCi 110 - 80.7mpg

Renault Captur Energy dCi 110

Citroen C3 BlueHDi 100

Renault Megane Sport dCi 130 - 70.6mpg

Peugeot 3008 1.5 BlueHDi 130 EAT 8 - 70.6


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