Two cars have achieved a top five-star rating in the latest set of results by Green NCAP, but the environmental test body plans to make its ratings tougher to achieve in 2022.
Green NCAP is an offshoot of safety body the European New Car Assessment Programme (Euro NCAP), promoting the development of cars that are clean, energy efficient and not harmful to the environment. Since 2019 it has been giving new cars a star rating in similar fashion to Euro NCAP’s crash-test programme.
In the latest set of results, which is the final batch of tests for 2021, the Lexus UX 300e and Nissan Leaf e+, both full battery-electric cars, earned maximum five-star ratings.
The Lexus and Nissan were rated in the three sectors of performance in clean air, greenhouse gas emissions and energy efficiency – the two EVs only lost fractions of points in the energy efficiency category.
Plug-in hybrids the Renault Captur E-Tech and Volkswagen Golf 8 GTE achieved 3.5 stars and the diesel-engined Audi A3 Sportback 35 TDI gained three stars, a result Euro NCAP described as creditable.
Commenting on the results recorded by the two PHEVs, Green NCAP accepted that plug-in hybrids perform at their best with fully-charged batteries, but both cars also have efficient after-exhaust treatment systems, cutting emissions when running on their petrol engines.
The Audi diesel performed very well in the clean air and energy efficiency tests but was let down by its greenhouse gas emissions. “Nevertheless, a rating of three Green NCAP stars is a solid performance for a traditional, diesel powered car,” testers commented.
In announcing its results Green NCAP also revealed plans to change the current criteria for cars which is based solely on tailpipe emissions.
From 2022 Green NCAP will base its tests on ‘well-to-wheel’, taking account of the environmental impact of producing the electricity for EVs. Green NCAP’s incoming technical manager Alex Damyanov admitted that looking only at tailpipe emissions flatters all-electric vehicles by ignoring the energy consumed in producing the electricity they use.
“Next year, we plan to also provide consumers with a total life-cycle analysis (LCA) which will allow them to see for themselves which car offers the cleanest mode of transport, depending on the use they make of the car, where their electricity comes from, where the vehicle is produced and how it is ultimately salvaged,” Damyanov said.