Emissions Testing Is Broken, and Other Lessons from the VW Scandal

In perhaps the most stunning example of greenwashing in the automotive industry, Volkswagen admitted on September 18 that 11 million diesel cars have been equipped with a ‘default device,’ an ingenious, if illegal, piece of software code.  Since 2009, this ‘default device’ has allowed VW diesel cars to detect when its emissions were being tested, and essentially switch to ‘test’ mode.  The result – VW diesel cars passed lab emissions tests, while real-world emissions of harmful air toxins were up to 40 times higher than the legal limit.      

While the fallout from the revelation will take years to play out, a few things are immediately clear. Potential costs to VW are estimated in the billions, U.S. and EU regulators have already announced  stepped up measures to detect any other so-called ‘defeat-devices,’ lawmakers are holding hearings and “clean diesel” now sounds like a punchline.  Beyond looking for any additional ‘defeat devices’, what lessons can regulators, lawmakers and stakeholders take away? 

We Need to Get Serious About Reducing Tailpipe Emissions

Transportation sector greenhouse gas emissions account for 27 percent of U.S. emissions. Within the transportation sector, gasoline is responsible for 59 percent of emissions and diesel another 24 percent.  The Obama Administration should be commended for the numerous regulatory steps it has taken to reduce emissions from cars.  Most recently, in 2012, the administration raised Corporate Average Fleet Emissions (CAFE) to 54.5 miles per gallon (MPG) by 2025.

But setting a strong rule is one thing.  Meeting it is another.  By all accounts, reaching a CAFE of 54.5 mpg in 10 years could be a challenge, but is achievable, with a combination of engine technology and improvements in fuels. Yet, if emissions aren’t properly counted, it will be difficult to measure progress. According to a back of the envelope calculation by the Guardian, the uncounted emissions from the VW diesel cars is the same as the total emissions from the United Kingdom – which includes power stations, vehicles, industry and agriculture.  

The best way to make sure the U.S. is on-track to reduce car emissions is to test vehicles and the fuels emissions using real-world conditions.  

Gaming Emissions Testing Is Perfectly Legal

VW’s activities were illegal, but there are other perfectly legal ways to skirt emissions regulations.  Where VW stepped over the line is installing the ‘default device’ in its diesel cars.  This allowed cars to detect when they were being put through emissions tests and take steps to lower emissions.  The legal option is to just design a car around emissions testing.  It guarantees excellent performance during the test, but not necessarily ideal performance in the real world.  The result is lower MPG ratings than as advertised by the manufacturer, and higher emissions. The International Council for Clean Transportation found in 2011 that emissions for a variety of cars in the United States are, on average, 35 percent higher in the real world versus the lab.

Like teaching to the test, these cars score high on the emissions test, but fail in the real world. 

There are several examples of manufacturers skirting emissions tests going back to the beginning of the Clean Air Act, as noted by the Center for Biological Diversity in their legal petition to EPA to use real-world emissions testing.  Most recently, Hyundai-Kia had to revise advertised MPG standards due to ‘calculation errors’ in their emissions tests, and pay a $300 million penalty for misleading consumers.  Other manufacturers have had to restate MPG ratings, but none received a fine.  It’s clear that fines are not enough of a deterrent against both legal and illegal emissions gaming. 

On the fuels side, manufacturers are required to use certification fuels, which are specifically designed for emissions testing.  These fuels don’t reflect real-world fuel properties, but are instead optimized for testing. In some cases these fuels are designed by the oil companies themselves.  

Test in the Real World, Not In a Lab  

When researchers at the University of West Virginia started testing the VW diesel cars, they wanted to show that clean diesel was possible.  Instead, it quickly became clear that the real-world emission results from the VW were very different than those from the lab.  Driving in the real world allows scientists to put a car through its paces. 

Why isn’t EPA already testing in the real world?  The agency already tests heavy-duty trucks under real world conditions, due to a similar scandal with these vehicles in the 1990s.  EPA argues that their lab testing is incredibly thorough.  In response to this most recent scandal, EPA claims to be stepping up measures to detect ‘default devices’ in diesel cars.  But their response is narrow, and doesn’t address the root problem. Real-world emissions testing would end the ‘cat-and-mouse’ game played between regulators and manufacturers.

Similarly, on a fuels side, things are much clearer in the real world. Real-world fuels are necessary in emissions testing, in order to understand how the engine interacts with the fuel. Without using real-world fuels, it’s impossible to know where exactly tailpipe emissions are from. What comes out of the tailpipe is directly influenced by what’s in the tank.

Reward Innovation in the Industry

U.S. automakers are pulling out the stops on vehicle technology to get to more stringent CAFE standards, but, as the VW scandal illustrates, it’s not an easy task to reconcile consumer and regulatory needs.  These emissions gaming measures place those manufacturers that do not skirt the rules at a clear disadvantage.  At the same time, falling gas prices and consumer demand for large vehicles are largely opposed to the need for smaller, cleaner cars.  How do you create clean vehicles that consumers want to buy?  All of the automakers are currently focused on this question.

The Department of Energy’s Quadrennial Technology Review calls for the co-optimization of fuels and engines, which will enable improvements in engine efficiency along with significant reductions in greenhouse gas emissions.  But in order to get there, significant incentive programs, continued investment in R&D and partnerships that foster clean technologies is what’s needed to get manufacturers to innovate. 

Support Robust, Transparent Compliance Programs

Finally, real-world fuels and emissions testing won’t happen without resources.  EPA will need significant resources to conduct these real-world vehicle and fuels emission tests, but everyone will benefit.  First and foremost, public health and the environment will benefit.  But equally important to realizing cleaner cars -- automotive manufacturers will be able to sell clean cars that people actually want to buy, instead of relying on gaming the system.

The technology exists to conduct real-world fuels and vehicle testing, but regulators need to have the manpower to execute these programs.  A weak regulatory program benefits no one.