The car maker will often choose a private technical service to oversee the tests in their own lab. Both the national authority and the technical service are paid by the car maker.
The national authority will choose the technical service. The car maker will only pay the national authority, who in turn will reimburse the technical service for their work.
The tests are based on the NEDC, a test protocol which has lots of loopholes. Car makers specially design ‘Golden cars’ to boost performance. Tricks include overinflating tyres, lowering the weight of the car and driving unrealistically.
Tests are based on the more lifelike WLTP and in turn the cars are more representative. Vehicles will also be checked on the road using portable equipment for emissions and fuel consumption.
The results are not usually made public or shared with other countries.
Results are made public and shared across the EU to improve transparency.
The prototype model goes into production and the manufacturer conducts its own checks on the cars.
During production, authorities carry out spot checks. That way, if the cars are not in conformity they will not reach the consumer.
Advertisements tend to overstate the green credentials of the car. There is a lack of reliable, relevant and comparable information today.
The advertisement will clearly show the real green credentials of the car using the official car label.
Because of the flaws in the current test, the car will likely guzzle more fuel and emit more pollution than the ad promised. Consumers can end up paying hundreds of euros more in annual fuel costs than otherwise expected.
To ensure the performance of the car is achieved on the road and over its lifetime, authorities carry out random spot checks.