Seven years ago, Nick Molden, founder and CEO of Emissions Analytics – an independent U.K.-based company, simply wanted to know why drivers were struggling to match official fuel economy figures. He started digging and soon discovered that the official testing regime – the New European Driving Cycle (NEDC) – was to blame.
According to Molden, manufacturers appeared to be legally exploiting the test to get the most flattering figures. He wanted to find out whether it was possible to come up with an alternative system which could provide a better number.
So, he found a device, the Portable Emissions Measurement System (PEMS), that was devised as a way to monitor some U.S. truck manufacturers who’d been caught using a crude defeat device to beat the emissions testing regime in the 1990s. Using some ‘clever maths’ and the PEMS, Emissions Analytics was able to begin real world testing in 2011.
The portable PEMS system works on the same underlying technology found in a traditional testing laboratory, but packaged for on-board installation. It measures the gases coming out of the tailpipe, as well as recording how and where the vehicle is being driven and furthermore, requires no modifications to the vehicle.
After 18 months of testing, they started to notice a problem with data relating to nitrogen oxides (NOx). They had always believed there was a fuel economy gap, but hadn’t really thought about NOx.
The International Council on Clean Transportation (ICCT) published research in 2014 on early Euro 6 diesels which showed they were 7.1 times over the legal limit for NOx.
Half of the data came from testing that EA had done. That was the first time a serious piece of their work had been put into the public domain. The findings were to prove crucial and a year later, Volkswagen admitted using a defeat device to beat strict emissions tests in the US.
EA’s facility in California has tested more than 500 vehicles in the U.S. since 2013 and plans to release its full findings on U.S. vehicles in early October. The goal is to give consumers an accurate and unbiased look at the true fuel economy and CO2 emissions of the vehicles they’re interested in and true impact on the environment. The EPA sticker is good up to a point, but companies like this can give a lot more information and let us know what’s really going into our air.
Here’s how EA conducts the testing:
• Instrument: Portable emissions measurement device strapped to the back of each test vehicle
• Measurements: Carbon monoxide, carbon dioxide, total hydrocarbons, nitrogen oxides, fuel economy and fuel consumption.
• Test course: 88 miles on public roads in Southern California that takes about 140 minutes to drive. Includes 6 passes on the nearby freeway -2 with AC on max, 2 with it off – averaging 65 mph, plus a 22-turn surface-street route with elevation changes and a 22.5 mph average that’s run twice with the AC on max and twice with it off.
• Vehicles: Usually sourced from media partners & rental agencies, each vehicle has 1,000 to 5,000 odometer miles and is tested in the default drive setting. Never sourced directly from the manufacturer, so as to not be given a ‘golden child’ to test.
• Fuel: Standardized Chevron gasoline in regular, premium and diesel varieties
Not surprisingly, four years of results in the U.S. show very little actual improvement in overall fuel economy, or decrease in CO2 emissions, according to EA.
Vehicles with engines smaller than 2 liters have seen essentially no change in fuel economy; vehicles with the most common size engines, 2 to 3 liters, have seen fuel economy decrease by around 8 percent, while vehicles with engines 3 liters or larger have seen an 8 percent increase in fuel economy.
This decrease among the most common vehicles is magnified in the U.S. because Americans are commuting longer distances without switching to smaller vehicles.
The EPA’s five-cycle test procedure is pretty accurate when compared with Emissions Analytics’ real-world tests; however, with stricter fuel economy regulations looming in the U.S., automakers could be lured into relying too heavily on efforts that have little real-world impact.
Consumers who pay attention to a brand’s fuel-economy credentials should be wary of automakers relying too heavily on “off cycle” credits. Off-cycle credits are those given to automakers by the EPA for technologies that help cut fuel use but aren’t accounted for in the standard city and highway test cycle. These include features such as engine stop-start during idle, “eco” driving modes, active grille shutters that improve aerodynamics and even ventilated seats, which can reduce the need for air conditioning.
Some brands use these technologies to make actual mile-per-gallon gains, while others use them for window dressing.
It’s the turbocharged engines that are particularly susceptible to large gaps between lab and street results. When a turbocharged engine is being tested under low stress and thus not engaging the turbos themselves, it produces significant fuel savings over a naturally aspirated engine. But once the turbos are engaged, the engine becomes far less efficient than a nonturbo unit.
Downsizing engines can be a good thing up to a point. If you go past a certain point though, you can find that the real-world mpg will actually get worse if you go too small. Downsizing is most effective when moving from larger engines — above 2 liters down to as little as 2 liters. As soon as you start going below 2 liters, that’s where we start seeing the gaps open up between EPA sticker and real world.
So what kind of technologies are successful in cutting fuel use and reducing CO2 emissions?
Hybrids — the plain type that have been overlooked recently as plug-in hybrid electric vehicles and pure EVs have gained recognition. Regular hybrids still offer significant cuts to CO2 and NOx and have highly sophisticated tuning to make sure they run at optimal efficiency rates and wring out excellent mpg results. They use minimal fuel when they need to, but can use an electric motor to help with acceleration and basically take over completely for city driving.
Beyond the typical Prius, Emissions Analytics’ EQUA Index shows that technologies such as multi-speed transmissions, lightening of the vehicle weight and proper tire choice – that is, not large-diameter rims wrapped in ultra-thin rubber – have a meaningful real-world impact that drivers will notice.
There are genuine efficiency improvements happening. The marketplace just needs to know so people can then choose the right vehicles when they’re in the showroom.
EA has additionally undertaken projects such as testing Low Carbon Trucks, Airport air quality, fuel testing of Techron for Chevron, and development of real MPG data for Motor Trend as well as other independent tests.