Is your new car actually less fuel efficient? It's all in how they test it

It’s not likely that gas prices are ever going to go down by much, which means many Canadians consider good fuel economy to be very important when buying a car. But when you look at the fuel efficiency figures on upcoming 2015 vehicles, they may look thirstier than the 2014 models.

It’s not because they actually use more gas. Instead, Natural Resources Canada is introducing a new testing procedure that results in more realistic fuel numbers.

“The government of Canada changed the fuel ratings to better reflect the fuel consumptions that (Canadians are) likely to achieve under today’s typical driving conditions and driving styles,” says Fabian Allard, deputy director at Natural

Resources’ Energy Efficiency transportation division. “We’ve been working with the auto industry on these changes for quite some time.”

Fuel efficiency testing isn’t done on a test track, but in a lab, since it’s the only way to guarantee consistency. Engineers run vehicles on a dynamometer, and determine fuel consumption by measuring the amount of carbon in the exhaust.

Up until now, engineers have used a two-cycle test. The city test starts with a cold engine, takes 31 minutes, and runs at an average 34 km/h, with 23 stops. The highway test starts with a warm engine, takes 12 minutes, and runs an average 78 km/h. In each test, the lab temperature is set between 20 C and 30 C.

The new five-cycle test also uses these, but then adds a cold-weather city test with the lab a chilly -7 C; a nine-minute air conditioning test, with the vehicle’s a/c running and the lab set to 35 C; and a nine-minute test that includes hard acceleration and a top speed of 129 km/h. All of these factors typically use more fuel.

Automakers do the testing and forward results to Natural Resources. The government sometimes audits results if it thinks the numbers aren’t right, or if a model hasn’t been tested for a long time or has new technologies. Auditors will use real-life vehicles purchased for the testing.

The EnerGuide labels on 2015 models will explain the new system and numbers. On 2016 labels, you’ll see information such as CO2 emissions, combined city and highway ratings, and comparisons with other vehicles in the segment. There will also be clearer information for alternative vehicles such as electric cars and plug-in hybrids.

Facts and tips

  • The new 2015 testing methods may produce fuel figures that are 10 to 20 per cent higher than the 2014 numbers.
  • Four-wheel drive vehicles are tested in two-wheel drive, and the results are adjusted for extra weight and engine load.
  • The 2016 Canadian label will align with the U.S., which has used five-cycle testing since 2008.

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