Fuel-economy ratings a sham Government ratings exposed

Most people would not purchase a household commodity without knowing exactly how much it was going to cost, yet the same folks buy or lease a car or truck without taking the total cost of ownership into account — everything from the purchase price to the operating costs, routine maintenance and so on.
A classic example surfaced when buyers of the Hummer H2 were asked which aspect of their new ride they liked least. Nearly all cited fuel consumption. Given the H2’s house-like aerodynamics and the V8 engine needed to force it through the air, the beastly consumption should not have come as a surprise, yet countless people were disappointed. How do you avoid a similar situation? Do your homework and don’t believe everything you read.
Case in point: The fuel consumption figures published by Natural Resources Canada need to be taken with not a grain but a generous heaping of salt. The numbers, as they appear on the EnerGuide label attached to all new cars and light trucks, can help when comparing one vehicle with a similar type of vehicle because the figures on each are equally optimistic. The reason they should not be used for budgetary reasons is simple — they bear absolutely no resemblance to the fuel economy one will realize in the real world.
The Ministry’s own website admits as much: “The actual fuel consumption of your vehicle will vary from its EnerGuide fuel consumption rating, depending on how aggressively and how fast you drive, and factors such as outside temperature, weather, traffic and road conditions. The operating condition of your vehicle, as well as the types of power-driven accessories (i.e., air conditioning) and external accessories (i.e., roof racks) installed on your vehicle will also affect your fuel use.” Who knew? Rarities such as traffic, temperature and road conditions affecting fuel consumption? Say it isn’t so!
The reason for the discrepancy between the published figures and the actual economy most realize boils down to the testing methods. The laboratory tests simulate driving the vehicle on a summer’s day and on a level, paved road with two passengers and a full tank of fuel aboard. All vehicles, including four- and all-wheel-drive models, are tested in two-wheel drive — the all-wheel-drive system is “physically disconnected.” What sort of economy can one expect when the all-wheel-drive system is physically reconnected?
The problems with the rest of the methodology are equally simple. According to Transport Canada, temperature has a huge effect on economy. When compared with that nice sunny test day, the same vehicle’s fuel consumption at 0C increases by about 8%. At -30C, fuel consumption increases by an average of 30%. Given that this is Canada and that most Canadians drive about a third of their annual distance during the cold season, why are the tests not conducted at a more realistic average temperature?
Then there’s the problem with the worsening road conditions all drivers face. Again, according to Transport Canada, rough asphalt, potholes and gravel roads can increase fuel consumption by up to 35%, and when the road is snow-covered, there’s the increased consumption associated with wheelspin and the fact that it takes more energy to move said vehicle down a snowy road.
Then there’s the test procedure itself. The simulated city loop is based on a 23-minute drive of 12 kilometres with 18 complete stops. The average speed of the test is 32 km/h. The simulated highway run is based on a 13-minute loop of 16 km with no stops. The top speed during the highway test is 97 km/h, and the average speed is 77 km/h. Tell me, when was the last time your typical commute or a trip to the grocery store mirrored either scenario? I venture never.
In fairness, EnerGuide’s fuel consumption figures are massaged to take some of the vagaries into account. They are “adjusted to account for the difference between controlled test conditions and real-world driving conditions.” Simply, the test-derived city economy is reduced by 10% and the highway estimate by 15%. Unfortunately, the tinkering just does not come close to reflecting the effect of deteriorating roads, the growing popularity of all-wheel drive and the fact that most cars are driven with the air blasting or the heated seats toasting buns.
Recognizing that the fuel economy numbers did not reflect the real world, the EPA (Environmental Protection Agency) in the U.S. adjusted its testing procedures for the 2008 model year. As well as doing the theoretical driving loops, the EPA added a hard/rapid acceleration test, began using the air conditioning during the tests and it now takes cold weather and its effect on fuel consumption into consideration. Canada needs to follow this lead.
More worrying is what happens when electric vehicles become significant players. As an all-electric conveyance uses no fuel per se, what does one measure and what is the real cost of operation?
There is no easy solution, but there has to be a better one than the current testing method. I suspect a lot of Hummer owners might have had second thoughts had they been given an accurate operational forecast at the time of purchase.
Source ottawacitizen.com