Engine Tier Changes Yield Cleaner Air

April 1, 2012
We refer to the progression towards clean diesels as engine tier changes. At Terex AWP, we have applied significant resources to the conversion to Tier

We refer to the progression towards clean diesels as “engine tier changes.” At Terex AWP, we have applied significant resources to the conversion to Tier 3 engines and now converting to Tier 4 engines in 2012 through 2014. In our focus on the cost and effort, we sometimes lose sight of how we are producing a healthier, cleaner world.

The conversion from unregulated Tier I engines in the mid 1990's to Tier 3 engines (called “Stage 3” in Europe) has already produced significant benefits. A European study shows that in spite of a 26-percent increase in diesel engine use in Europe there has been an 80-percent reduction in poisonous carbon monoxide gas and a 40- to 60-percent reduction in other poisonous exhaust gases because of the Stage conversions. Studies of diesel operators show a 31-percent increase in cancer risk and those who are around diesel exhaust (such as construction workers, border guards, and those who ride school buses) are at an even bigger risk. Clean diesels present significant improvements to the health and quality of life for all of us, since we all breathe air with diesel exhaust. To fully realize the potential health benefits we need to implement Tier 4.

Diesel engines built until 2006 were surprisingly archaic compared to our gas-powered automobile engines. While almost all cars went to computer-controlled, fuel-injected engines by the late 1980's, diesel engines were still mechanically controlled similar to early 70's automobiles. Tier 4 engines greater than 25 hp (greater than 50 hp in Europe) are direct-fuel injected and computer controlled, just like all cars built in the past 20 years. These new engines will be installed in Genie telehandlers this year and most Genie aerials in 2013 and 2014. Their electronic controls combined with other measures reduce carbon soot by 90 percent bringing associated health benefits to everyone living in the U.S. and Europe.

The nostalgia around mechanical-controlled engines is far more myth than fact. Distributors and carburetors, components long gone from cars, were fickle and required frequent tinkering. Up until the early 1980's, most households had a resident “mechanic.” Today cars require very little maintenance, rarely break, and a “tune-up” is performed hundreds of times per minute by the engine's computer. Rare maintenance is simplified as mechanics plug an inexpensive, simple machine (available at auto parts stores for less than $100) under the dash and the engine tells them specifically what problems exist. In addition to cleaner exhaust, Tier 4 engines bring these service and reliability advantages to our diesel engines adding additional value for the cost and pain of conversion.

A great example of the success electronically controlled engines can bring is the Ford EcoBoost engine line. Ford employs the same advances used in our Tier 4 diesels: computer control, direct injection, and turbocharging. Ford has been so successful with these technologies that in 2013 the Ford Escape will no longer be offered as a hybrid because the standard EcoBoost engine is more powerful and more fuel efficient than the current hybrid model. Expect these types of improvement in our diesels as the technology is tuned to even better performance and cleaner emissions.

Clean diesel technology is literally creating a brighter future for generations to come.

Brad Allen is vice president, product management and engineering, Terex Aerial Work Platforms.