While laboratory-based emissions testing can help keep polluting vehicles off the road, they alone are not enough. What is needed is new technologies, such as remote emission sensing (RES). RES uses sensors and cameras to automatically measure exhaust emissions from vehicles in real-world operation.
While RES may be a proven technology, it is not widely used – due in large part to its need for highly skilled personnel and associated high costs. But this could soon change, thanks in part to the work being done by the EU-funded CARES project. To accomplish this goal, the project focused on developing a number of cost-effective RES solutions that can be easily implemented and used. This includes two new low-cost emission sensing point sampling sensors. Once these innovative sensors are installed along a roadside, they can be used to measure soot particles and particle number emissions. The project also advanced existing plume-chasing RES technology.
In addition to developing new technologies, the CARES project built several tools for analysing the vast amounts of data captured by RES.
According to Sjödin, a transportation and mobility researcher at the Swedish Environmental Research Institute, the typical RES set-up will record thousands of samples every day. “This data can paint an accurate picture of vehicle emissions at a particular location,” he notes. To help make such a comprehensive picture possible, the CARES project developed a state-of-the-art, EU-wide RES database that allows users to interact and visualise aggregate data.
There’s also openCARES, a software package that enables non-experts to analyse large sets of RES data and assists them in preparing measurement reports. The project’s RES technology and data solutions were demonstrated in Milan, Krakow and Prague. In Prague, they successfully identified Euro 5 and Euro 6 heavy- and light-duty diesel trucks with malfunctioning or tampered emission control systems. Across all sites, the system observed that some Euro 6d-Temp and Euro 6d diesel vehicle families show high on-road NOx emissions – a good indicator that they may not comply with emission standards.
