In practice, pumping up your own car tyres proves not always to guarantee the right tyre pressure. A practical survey among 92 users of conventional petrol-station pumps has shown that tyre pressure was increased by only 0.2 bar on average, while a 0.4 bar increase was the aim and anticipated outcome. Over one-third of the users even unintentionally reduced the pressure in at least one of their tyres, because the pressure was initially higher than what they had set on the pump. These real-world measurements also showed that users are unaware of correction factors for winter tyres, warm tyres or ambient temperatures, or at least do not apply them. To make matters worse, in some cases the petrol-station pump signals an error with the same sound as heard when the tyre pressure has been raised, erroneously prompting users to stop pumping. After pumping, the pressure of almost 50% of tyres is lower than the recommended value. On virtually all the pumps where the practical measurements were done, there was an instruction sticker distributed by the ‘Opt for the Best Tyre’ public information campaign.
If more efficient use were made of the petrol-station pumps, for the Netherlands as a whole this could reduce CO2 emissions by as much as 0.28 Mt CO2 annually and reduce fuel expenditure by €190 million. These are two of the main findings of this CE Delft study. Indirectly, the decrease in fuel production (due to reduced fuel consumption) and longer tyre life mean a further annual CO2 reduction of slightly less than 0.1 Mt.
Under the Dutch National Climate Agreement, the aim is for 50% more people to drive with the right tyre pressure by 2030, to cut CO2 emissions. It is recommended to investigate whether there are other options besides information campaigns to prevent suboptimal use of conventional tyre pumps.