EPA Proposes Grading System For Car Fuel Economy

suraj.sun writes with this snippet from CNET: "The EPA and Department of Transportation on Monday proposed a fuel economy label overhaul to reflect how electric and alternative fuel vehicles stack up against gasoline passenger vehicles. ... The changed label, mandated by the 2007 energy law, includes the same information on city and highway miles per gallon and estimated driving costs based on 15,000 miles a year now available. But the new labels add more comparative information, rating cars on mileage, greenhouse gas contribution, and other air pollutants from tailpipe emissions. That means that consumers can look at a label to see how one vehicle compares to all available vehicles, rather than only cars in a specific class. One label proposes grades, ranging from an A-plus to a D. There are no failing grades, since vehicles need to comply with the Clean Air Act."

Comments

Re:Giant letter?

[cappp]

I sometimes feel bad for the guys in charge, it's apparently impossible to please people. We're normally clamouring for more information, operate our markets with the assumption of perfectly informed agents, run democracies that were conceived presuming some degree of voter knowledge, and heap disdain on the apparently ignorant. But a government agency tries to help consumers make decent choices by undermining the ability of companies to easily obscure certain basic information and they're told people want less info of a specific type. We’re a capricious lot.

I had a look at the two proposed sheets and thought they were nicely thorough, explained the basic assumptions, and presented the info in an easily comparable fashion. Guess it takes all sorts.

Misleading CO2

[Antony T Curtis]

The CO2 emission numbers would be misleading for battery electric and plug-in hybrids because it only states the tailpipe emissions.

Example... A battery-electric vehicle may use 34 KW/h of electricity per 100 miles. According to official data, in the USA, about 0.6 Kg of CO2 is emitted for every KW/h of electricity consumed. So for every 100 miles, about 20 Kg of CO2 is released into the atmosphere. So the data should state that 200g of CO2 is emitted per mile, not the 0g it currently states.

Ignoring other sources of CO2 emission and only looking at tailpipe emissions are misleading for technology which does not have a tailpipe. For example, a battery electric vehicle which uses 40 KW/h of electricity per 100 miles would release more CO2 into the atmosphere than many small gasoline vehicles.

Problem with that....

[mark-t]

If a car performs really well, it might get an A...

But then a few years down the road, improved technology could make that A rating in 2010 look like a C- or D in 2015, and other "A" rated cars come out that perform far better. Yet the 2010 car still has the "A" rating... so it isn't fairly compared to newer cars.