We use cookies to allow us and selected partners to improve your experience and our advertising. By continuing to browse you consent to our use of cookies. You can understand more and change your cookies preferences here.


Updated: 13 May 2022

How green are electric cars? Green NCAP releases first life cycle assessment figures

‘Cradle to grave’ life cycle assessment figures show electric cars are responsible for less greenhouse gas emissions than others, but energy from renewable sources plays a pivotal role

Green NCAP has released its first life cycle analysis (LCA) figures for 61 cars. The figures include the total amount of greenhouse gases and primary energy demand required for the extraction of raw materials, manufacturing, distribution of cars, along with their running, recycling and final disposal.

  • Study finds amount of greenhouse gases associated with electric cars is less than other fuel types of car, largely influenced by amount of energy from renewables
  • Countries with a low share of energy from renewables can result in an electric car generating more greenhouse gases over its lifetime compared to petrol or diesel car
  • A car’s efficiency, mass, size of battery along with driver habits, usage and weather conditions also influence greenhouse gases and primary energy demand, particularly for plug-in hybrids
  • Smaller and lighter vehicles tend to be better for the environment
  • Green NCAP tool (launching in May) will let people compare the impact of running cars in different countries

The new Green NCAP study, which used a methodology developed by Joanneum Research and was peer-reviewed by the Paul Scherrer Institute, found that greenhouse gas emissions (GHG) for electric cars are generally lower than non-electric cars. However, this is based on the average renewable energy mix from 27 European countries, including the UK.

The reality behind this average is that a country with a high amount of energy coming from non-renewables can mean an electric car is actually worse for the environment than a petrol or diesel car.

In contrast, running an electric car in a country with a high amount of energy from renewables means it has significantly less impact on the environment compared to its petrol and diesel counterparts, placing more pressure on governments around the world to prioritise energy from renewables.

Green NCAP has also calculated primary energy demand (PED) as part of its LCA analysis, and the results are much less clear cut - it found electric cars have a comparable PED to other fuel types of car.

The 2022 Which? car survey is now open. Tell us about your car and you could win £2,500 (T&Cs apply).


Cars with the lowest greenhouse gas emissions

Taking the lifetime of a car into account, it's electric cars that have the lowest amount of greenhouse gas emissions.

However, while electric cars have zero tailpipe emissions, a large quantity of greenhouse gases (GHG) is created while producing them - more so than a petrol or diesel vehicle. There is a significant GHG cost to producing the high voltage battery that an EV requires.

Add to that the estimated GHG emitted in supplying the electrical energy over 240,000km (approximately 150,000 miles, or 9,320 miles annually for 16 years), and the life cycle emissions are actually fairly close to some of its combustion-engine counterparts.

Drive smarter and cut costs using our expert advice. Get our Cars newsletter – it's free monthly 

Car with the lowest and highest lifetime greenhouse gas emissions

These are the 15 cars from Green NCAP’s study with the lowest GHG emissions, and the five with the highest.

RankCarFuel typeClass/sizeLCA - greenhouse gas emissions (g/km)
1Fiat 500eElectricCity car119.1
2Hyundai KonaElectricSmall SUV130.8
3Renault ZoeElectricSmall car131.8
4Volkswagen ID.3ElectricMedium car134.4
5Nissan Leaf e+ElectricMedium car142.2
6Lexus UX 300eElectricSmall SUV147.8
7Toyota Prius PHEVPetrol PHEVLarge car163.3


Full figures and fact sheets for each car are now available from Green NCAP. All cars tested between 2019 and 2021.

As you can see in the table above, the Ford Mustang Mach-e electric car (full review coming soon) is calculated to produce more GHG than the diesel-powered Skoda Octavia.

However, when compared against similar sized SUVs, the Ford Mustang Mach-e has significantly less emissions than its closest sized car in the same study, the Ford Kuga. It is also significantly better than the Mitsubishi Outlander, which is estimated to produce just over 100g/km of greenhouse gasses more than the Mach-e. 

More renewable energy means greener electric cars

It might seem obvious to say that when more of your electricity comes from renewable sources, the greener an electric car becomes - but the difference really is staggering.

Taking the Volkswagen ID.3 electric car as an example (pictured above), Green NCAP found that if you are driving and charging this car in Sweden - the country with the highest share of electricity from renewables - the GHG required to generate the electricity is so low that it is substantially lower than all forms of combustion car.

Whereas in Poland, which in Green NCAP’s study has the highest amount of electricity generated from burning coal, an electric vehicle will actually have higher life cycle GHG emissions than a petrol or diesel car, making it much worse for the environment.

As a hypothetical, Green NCAP also points out in its study that should electricity come from purely renewable sources, the electricity required to keep the ID.3 driving for 150,000 miles would be so small, the total greenhouse gasses over the vehicle’s lifetime would be half that of a non-electric car.

Green NCAP plans to launch a tool toward the end of May, which will let you compare the impact of running cars in different countries and look at the predicted energy mix in the future.

Primary Energy Demand (PED) and future LCA rating

An important part of the LCA calculation is the PED; the sum of all primary energy extracted to provide the transportation, including coal, oil, natural gas, hydro energy, wind, waste, solar and nuclear energy.

But while the PED is also strongly impacted by the size and mass of the vehicle, and the size of the high voltage battery in EVs, Green NCAP has found that EVs and combustion cars are relatively comparable.

This table shows the five cars with the lowest PED and the five with the highest. 

RankCarFuel typeClass/sizeLCA - Primary Energy Demand (kWh/km)
1Fiat 500e
City car0.67
2Skoda Octavia
Large estate0.69
3Toyota Prius PHEVPetrol PHEVLarge car0.69
4Peugeot 208DieselSmall car0.70
5Toyota YarisPetrol full hybridSmall car0.73
57Land Rover Discovery SportDieselLarge SUV1.17
58Mitsubishi Outlander PHEVPetrol PHEVMid-size SUV1.22

Full figures and fact sheets for all 61 cars available from Green NCAP. All cars tested between 2019 and 2021.

Green NCAP say it’s still too early to produce an overall LCA rating, and is currently sticking to simply publishing its figures.

It should be noted that Green NCAP’s LCA looks primarily at greenhouse gasses and energy, but currently does not include environmental effects of pollutant emissions like oxides of nitrogen (NOx), sulfur dioxide (SO2) and particulate matter. Consequential impacts like acidification, ozone formation, and toxicity to humans are not considered.

The life cycle impact of a transport system on water demand, pollution of water or soil are also not yet included in the assessment. 

Find out which electric cars we recommend by heading to our roundup of the best electric cars

UPDATE NOTE: This story was updated on May 13, 2022 following revised data from Green NCAP.