It seems switching to an EV can only scratch the surface of the clean air problems due to motor transport. Since their batteries make them heavier than fuel-burning cars they should have greater tyre wear, creating more road debris. Of course the parallel claim is that there will/would be some noticeable (presumed beneficial) effect on the climate in the long term due to lower CO2 emissions, but as we’re also told there’s little time left and sales of EVs are minimal, that doesn’t look good for climate alarmists either.
A new report released by the Air Quality Expert Group (AQEG) in the UK recommends as an immediate priority that non-exhaust emissions (NEE) are recognized as a source of ambient concentrations of airborne PM, even for vehicles with zero exhaust emissions of particles, reports Green Car Congress.
Non-exhaust emissions (NEE) from road traffic refers to particles released into the air from brake wear, tyre wear, road surface wear and re-suspension of road dust during on-road vehicle usage. These emissions arise regardless of the type of vehicle and its mode of power, and contribute to the total ambient particulate matter burden associated with human ill-heath and premature mortality. No legislation is currently in place specifically to limit or reduce NEE particles, so whilst legislation has been effective at driving down emissions of particles from the exhausts of internal-combustion-engine vehicles, the NEE proportion of road traffic emissions has increased.
Data from the UK National Atmospheric Emissions Inventory indicate that particles from brake wear, tyre wear and road surface wear currently constitute 60% and 73% (by mass), respectively, of primary PM2.5 and PM10 emissions from road transport, and will become more dominant in the future. Currently they contribute 7.4% and 8.5% of all UK primary PM2.5 and PM10 emissions. Therefore to achieve further gains in PM2.5 and PM10 air quality in relation to road transport sources requires attention to reducing non-exhaust emissions, not solely a focus on lowering exhaust emissions.
—“Non-Exhaust Emissions from Road Traffic”
NEE particles are also an important source of metals to the atmosphere; the UK national inventory estimates NEE contributions of 47% and 21% for Cu and Zn, primarily associated with brake and tire wear, respectively. The national inventory does not include estimates of road dust re-suspension.
via Tallbloke’s Talkshop
July 14, 2019 at 08:16AM