Green Energy News | May 27, 1996

May 27, 1996 – Vol.1 No.9

ENERGIES... week of May 27, 1996

A RIDE ON A TREADMILL. This editor recently volunteered his 10 year old station wagon for the optional dynamometer emissions test offered here in the State of Maryland. The test is considered a more accurate method of checking the condition of pollution control equipment than a typical idle test (also offered) since it attempts to simulate real driving conditions.

The state spent millions of dollars building the 19 new emissions testing stations, only to have the dyno test virtually shut down by special interest groups and motorists who didn’t want their cars subject to the rigorous test, nor allow others to drive their beloved chariot.

THE TESTING PROCEDURE is accomplished by a technician who “drives” the car along a computer graph visible on a monitor nearby. He (in this case) must follow the graph along its hills, valleys and straights by varying the speed of the car with the accelerator and shifting, if need be, in a stick shift car like mine. The test is not unlike a computer video game. It’s pretty exciting, but my car failed the test.

THOUGH CLEARLY SUPERIOR to an idle test, the procedure and the equipment need some improvement. It is difficult, even for the technician, to coax the car onto the big steel dynamometer rollers. Dyno rollers that rise into position would be make the task easier, but certainly more expensive.

The test also does not seem to consider the effect on pollution levels of driving techniques. In this case the technician did not upshift into higher gears as soon as I would have and did not even attempt to put the car into overdrive along the simulated highway. Better training would help.

Popularity of the test might be improved by opening the testing stations to repair shops and car buffs. (For a fee, of course.) Dynamometers can tell a lot more about car performance than emissions, and few repair shops have such expensive equipment. Power output, fuel economy and drive train condition could be tested at speed and under load. This information would be helpful to mechanics and car owners while helping to ease concerns over the testing procedure.