Part 1—What the increasing standardization of emissions testing and regulations mean for automotive sensors
As the world moves toward harmonizing vehicle emission standards and new testing regulations, what do these developments mean for the automotive sensors market?
The question is an important one, especially at a time of unprecedented flux for the automotive industry. In the face of two factors—the unification of standards governing emissions and their measurement, and the electrification of engines—sensors in cars will be considerably impacted in the next 10-15 years. As a result, vehicle architectures, systems, and underlying components will all be radically affected, in the process generating a slew of new opportunities for sensor makers.
At the same time, car makers will try to claw back as much as possible the all-important return on their existing investments. This means vehicle manufacturers will push internal combustion engines the furthest they can go within the current regulatory framework. Before too long, however, vehicle OEMs will embrace new systems and architectures as a response to fresh and tougher legislation on carbon dioxide (CO2) emissions.
Standards and testing are harmonizing
On the first factor, the most important player today in the growing synchronization of global testing standards for passenger-car emissions is China. California may have the world’s toughest legislation on emissions, achieving on the world stage a prominence normally reserved for nations, not states. And yet China is not far behind North America or European emissions legislation. In fact, the country is moving its legislation to CN6a, which resembles current Euro 6 norms, by 2020.
The China specification calls for fewer allowable particulates in gasoline per kilometer, taking its cue from European requirements that also standardize nitrogen oxide (NOx) emissions.
In Europe, the Euro 6c and Euro 6d TEMP specifications, which came into force in September 2017, build on existing Euro 6 regulations dating back to 2014. Under these more stringent rules, new vehicles must demonstrate that they can meet original target requirements on NOx and particulate output of the exhausts under harsher test conditions. Those conditions apply to exhaust performance on the road as well as in the lab—i.e., via a world-harmonized testing procedure called WLTP under Euro 6c, and including Real Driving Emissions (RDE) testing under Euro 6D TEMP.
These tests have meant that OEMs are looking to extend their aftertreatment technology, even into gasoline engines, for example, via the adoption of gasoline particle filters (GPFs) for gasoline direct-injection (GDI) engine vehicles in European-sold vehicles. Such filters are already used to drastically reduce particulate output in diesels. And the close similarity in the Chinese regulations will accelerate adoption of GPF in GDI engines as soon as 2019. A GPF needs at least one differential pressure sensor for on-board diagnostics of the filter, and some OEMs even consider the use of high-temperature control monitoring.
Within two years, then, a Chinese-made car can be considered in much the same way as a European car in terms of sensors, especially in the case of exhaust emissions management. And because China is the world’s largest car market, last year selling 28 million cars—more than North America and Japan combined—its readiness to accept and implement strong emissions-related measures is significant.
To be sure, the adoption at present of GPFs by European brands, especially Mercedes-Benz and Volkswagen, has been a boon for the suppliers of MEMS pressure sensors. Suppliers are already reporting strong traction for the sensors, and pieces numbering in the multiple millions are anticipated this year.
The chart below shows global revenue of MEMS pressure sensors for gasoline particle filters in both diesel and gasoline engines, according to IHS Markit projections. The updated emissions specifications and their implementation will result in very rapid adoption of pressure sensors.
India joins green wave
Besides China, other countries are also looking to clean up the air, especially in their cities. The New Delhi government in India, for instance, has a roadmap to promote green cars, and will accelerate its current Bharat 4 emission regulations plan to bring it in line with that of Europe. This means that India will bypass Bharat 5 altogether and go straight to Bharat 6, which is similar to Euro 6 emissions legislation, by 2020.
Nonetheless, a considerable challenge is in store for the car market in India, given the cost in extra exhaust treatment equipment needed by Indian-made cars to meet the legislation. To this end, IHS Markit believes Indian car makers will initially adopt exhaust-gas recirculation technology in gasoline engines to mitigate vehicle output of noxious nitrogen oxide, along with the use of three-way catalysts. The country is unlikely to adopt the more expensive GPFs on top of this approach, especially as approximately 50% of Indian vehicles use multi-port injection and not direct-injection fuel systems, which significantly mitigates the particulate output on the engine side.
What about diesels?
Generally, RDE measurements will mean that OEMs must strive harder in the future to ensure that their vehicles live up to lab measurements on harmful NOx and particulate output when on the road. There is a phasing-in period, but the trend is to spur new vehicles toward conformity via ever-more sophisticated exhaust cleaning strategies.
For diesels in Europe, such a requirement already accelerates the use of selective catalytic reduction (SCR) systems, which inject urea and water into the exhaust to further reduce NOx. Manufacturers of diesels in Europe and North America are now more widely adopting this approach. The SCR fluid tank has a temperature and level sensor, and occasionally a quality sensor based on optical or ultrasonic technology to prevent incorrect dilution of the urea. These three measurements can sometimes be combined in a single “smart” sensor.
In the US market, there are even more stringent regulations for on-board diagnostics relating to the operation of the particle filter, which drove the use of particulate mass (PM) sensing in diesels already from model year 2014. At present, large European SUVs and other large diesel engines from US manufacturers feature PM sensors, in addition to the pressure sensor, to ensure that the filter is working to specification over the life of the vehicle.
Note: More details can be found in my latest report, “Another good year for automotive MEMS sensors,” available to IHS Markit subscribers.