The EPA changed the test for 2008. They have not retested old models but will estimate the reduction using an undisclosed formula. The 2004 Jetta TDI auto wagon was 32/43. Under the new test they estimate 28/39 for an average of 32.
Ah, OK. Sorry, I haven’t kept up with the busybodies, I see.
The stupid thing about this is that if one goes to the EPA site (fueleconomy.gov) and noodles around, one sees that the MPG figures submitted by vehicle owners are most often higher than what the EPA is quoting, esp. on diesel vehicles.
Proving that government employees are morons, because the average joe on the street, whom the EPA claims to be simulating, is getting higher mileage than the old system and the new system, ergo, bureaucrats are dumber than the average citizen.
But we already knew that.
The consideration of air conditioning in the MPG figures will likely lead to new AC technologies. It does take a fair bit of energy to run the AC compressor. This could be done away with by using a Seeback/Peltier thermo-electric cooling setup, and scavenging exhaust heat to power it. Wha-la, no more compressor, only a fan.