Last Friday, Sept. 18, the U. S. Environmental Protection Agency (EPA) announced that it had discovered a "defeat device" installed in nearly half a million diesel vehicles made by Volkswagen (VW) and sold in the U. S. from 2009 to 2015. Specifically, EPA claims that VW engineers have admitted to designing and installing software that implements full emissions controls on their diesel engines only when the software detects that the car is undergoing emissions testing. The rest of the time, some of the emissions controls are disabled, allowing the vehicle to produce as much as forty times the maximum allowed levels of NOx, a type of pollutant that can lead to respiratory problems and smog. When queried about the accusations, VW spokespersons declined comment, citing the ongoing investigation.
Until VW has their day in court, or wherever this case ends up, fairness dictates that we give them the benefit of the doubt. But when both the EPA and the California Air Resources Board (CARB) issue notices that VW is in violation of clean-air ordinances, citing admissions made by VW personnel, it's a fairly safe bet that something is amiss.
In 2014, some researchers at West Virginia University who were working for the International Council on Clean Transportation discovered that certain VW diesels emitted far more pollutants when operating under actual road conditions than one would expect from the fact that they are certified by the EPA for sale in the U. S. When the researchers notified the EPA about this, EPA asked VW about it, and VW said they would issue a recall to recalibrate the systems involved, which they did in December of 2014. However, the California Air Resources Board checked some of the supposedly fixed VWs in May of 2015, and found that some of them were still out of compliance—hence, more meetings with VW. According to a letter from the CARB, its staff and EPA staff held a technical meeting with VW personnel on Sept. 3, 2015. Reading between the lines, we can surmise that the question they asked was along the lines of, "Okay, guys, what's really going on here?" Faced with the inevitable, VW admitted that they had deliberately designed the vehicle's software to detect an official emissions test, and to turn on all the pollution controls only during testing. The rest of the time, some of the controls were inactive.
Faced with this smoking gun (so to speak), EPA and CARB had no choice but to declare the affected vehicles in violation and to order VW to issue a recall to remove the defeat-device software.
As it turns out, if the allegations prove true this isn't the first time that regulators have found diesel-engine defeat devices deployed on a massive scale. Back in 1998, diesels in trucks and construction machinery made by Caterpillar, Renault, and Volvo were found to have two different sets of software. One set was used when the EPA was running emissions tests on the engines, and adjusted the injection timing for low NOx emissions. The second set of software used a different injection timing that delivered better fuel economy, but also caused more NOx emissions. The manufacturers ended up paying about a billion-dollar fine for that infraction.
There seems to be something about software that tempts engineers to bend the rules. With hardware, it's relatively easy to dig into the machinery and find the gizmo that's doing its nefarious work—that's the kind of thing that the term "defeat device" brings to mind. It reminds me of a scene from the autobiography of Vannevar Bush, who was in charge of the U. S. Office of Scientific Research and Development during World War II. In the 1920s, he was a professor at MIT and got involved with a startup company named Raytheon. At the time, Raytheon's hot product was a type of rectifier tube that was useful in the rapidly growing production of radios that operated from power-line current (earlier radios used messy and expensive batteries). In a dispute with rival radio manufacturer Westinghouse, Bush claimed that Westinghouse was using Raytheon's patented tube structure. The patent attorney for the rival firm rival denied it. In response, Bush told Westinghouse's patent attorney to pick up a Westinghouse tube (which had an opaque coating on the glass) and crack it over a trash can. He did so, and there was Raytheon's patented tube structure. As Bush put it, the patent attorney agreed to advise his client Westinghouse to "keep off the grass."
You can't do that sort of dramatic stunt with software so easily. If the accessible form of the software involved is in the form of machine code (which it usually is in production systems), often nobody other than the people who wrote it can really tell what it does. So sneaky evasions such as the one VW engineers are accused of doing with the defeat-device software are hard to pin down, which means that indirect evidence such as performance measurements have to be used instead. And it's not often that regulatory agencies go to such trouble to track down violations. Further investigation may reveal exactly who at VW was responsible for the defeat-device software, and how high in the firm the decision was made. And then, if the charges are proven, VW will have to pay—at least with a recall fixing the problem, and perhaps with fines or other penalties.
The contrast between the way cars used to pollute before environmental regulations and what comes out the tailpipe today was brought home to me recently when we started working on a 1955 Oldsmobile owned by my late father-in-law. It now starts up pretty reliably without help, but whenever it does, a blue cloud appears behind it and the sharp tang of volatile organic compounds (VOCs) fills the air. Exhaust just doesn't smell like that any more, by and large, and that's thanks to catalytic converters, selective catalytic reduction for diesels that uses urea to reduce NOx emissions, and many other measures that make the air cleaner than it would otherwise be.
If the charges against VW prove to be true, that firm will have the opportunity to make the air behind its cars even cleaner. And we will all be thankful for that.
Sources: Numerous news outlets carried reports of the EPA's press release of Sept. 18, which can be found on the EPA website at yosemite.epa.gov/opa/admpress.nsf/21b8983ffa5d0e4685257dd4006b85e2/dfc8e33b5ab162b985257ec40057813b!OpenDocument. I referred to reports on the issue by the Washington Post at http://www.washingtonpost.com/news/energy-environment/wp/2015/09/18/epa-volkswagen-used-defeat-device-to-circumvent-air-pollution-controls/and a letter from the CARB at http://www.arb.ca.gov/newsrel/in_use_compliance_letter.htm. I also referred to an article on the 1998 defeat-device actions in the Los Angeles Times for Oct. 23, 1998 at http://articles.latimes.com/1998/oct/23/news/mn-35220. The patent dispute between Raytheon and Westinghouse is described on p. 198 of Vannevar Bush, Pieces of the Action (William Morrow, 1970).