*The Three R's to Cleaner Engines: Replace, Retrofit or Retire

Aug. 1, 2001
Most people know the three R's of reduce, reuse and recycle that define the eco-era. But what about the three R's facing the equipment industry in terms

Most people know the three R's of reduce, reuse and recycle that define the eco-era. But what about the three R's facing the equipment industry in terms of emission regulations: replace, retrofit or retire. While the EPA and state agencies are looking forward to the brighter, cleaner future of off-road equipment, many rental centers still employ a fleet aged at 10 to 15 years old.

Stringent emissions regulations for off-road engines will take effect in 2004 and again in 2007. Planning ahead and taking action now will ease the blow in the years to come.

The ideal option would be to replace older models with newer, more efficient units that feature the latest technologies. Some companies have the ability to keep their fleets young and constantly replace outdated units with ‘greener’ machines. “The average age of our fleet is about 2.8 years old, so we're actually in the process of reducing the inventory of the older equipment through used equipment sales and auctions,” says Pricilla Oehlert, director, risk and safety of Scottsdale, Ariz.-based Rental Service Corporation. “In relation to Tier 2 and Tier 3 emission standards, we are working with Brown and Caldwell (a national environmental consultant) to evaluate and create an emission reduction plan that will encompass the entire corporation and not be just state specific.”

Phasing out

Although ideal, most rental centers do not have the funding to replace entire fleets every few years. In this case, the center will need to implement a gradual phasing-out program where certain products are singled out and replaced.

Outdoor power equipment has been a focal point of interest for the past decade, especially in California. Tightening existing 2000 standards, pending 2002 emission standards of the California Air Resources Board have forced small engine manufacturers to find new solutions to reduce emissions. “Prices for new technologies can be anywhere between 10 and 15 dollars per unit. It's part of the tradeoff to have better equipment [with] better fuel consumption,” says Robin Pendergrast, consultant for Lake Zurick, Ill.-based Echo.

According to Milwaukee, Wis.-based Briggs & Stratton, who claims “70% emissions reduction since 1990”, four important technological advances of small four-cycle engines have helped reduce pollution: 1) oil control that prevents oil from getting into the combustion chamber; 2) minimizing the surface area and crevice volume of the combustion chamber to reduce hydrocarbon emissions; 3) providing the optimum mixture of air and gasoline; and 4) overhead valve (OHV) design that reduces fuel consumption and delivers a 20 percent increase in power.

Two-stroke engines, used to power trimmers, blowers and other hand-held products, are a strong source of hydrocarbon emissions. Hydrocarbons are classified as volatile organic compounds and when combined with nitrogen oxides, create ground-level ozone, which threatens human health.

“Hydrocarbons come from unburned fuel,” says Allen Daily, director of marketing engine technology with Raleigh, N. C. -based John Deere Consumer Products. “About 25 percent of the fuel remains unburned in a conventional 2-stroke engine.” John Deere's new ecoPower is a compression wave injection technology that incorporates the addition of an injector tube to the side of the engine designed to serve as the staging area for incoming fuel, preventing it from escaping through the exhaust port. This technology reduces hydrocarbon emissions by 75 percent, John Deere says.

CARB Tier 2-certified engine families must display information regarding the Emissions Durability Period and the Air Index on the engine emissions label. Consumers should understand these ratings and be familiar with the information they convey. The durability period refers to the unit's emissions-compliant lifespan (in hours) and the Air Index is a rating from 0 - 10 based on the emission output level of the engine family (the lower the number, the cleaner the engine).

Stepping up

A less extreme replacement strategy is to re-power units with new engines or retrofit units with exhaust treatment systems. Larger diesel-powered units are an expensive investment and it may not be feasible to work new purchases into a tight budget.

Heavy-duty engines aren't exactly an inexpensive alternative, however new engines often feature reduced noise levels, higher torque and increased fuel efficiency. Diesel engines cause a great amount of pollution concern across the country. In response to this concern, the EPA has a two-step plan that will begin in 2004 with new emission standards. Come 2007, more stringent standards will be enforced in combination with cleaner, low-sulfur diesel fuel requirements.

Serving as the staging ground for the rest of the country, cities such as Houston and Dallas-Fort Worth are already experiencing an accelerated surge in emissions regulations. According to the Texas Natural Resource Conservation Commission, plans to phase out old off-highway equipment will force equipment owners to purchase Tier 2 and Tier 3 machines beginning in 2004 and restrict fleet age to no more than 6 years by 2007.

To get the ball rolling on diesel emission reductions, the EPA's Voluntary Diesel Retrofit Program was created to help heavy equipment owners develop effective retrofit plans. Retrofitting is a term used when referring to the early replacement of older engines with newer ones, the addition of new pollution control after-treatment equipment, upgrading an engine to a cleaner “certified-like configuration” or the conversion of any engine to a cleaner fuel.

Catalytic converters, or exhaust treatment products, can be the solution for certain engines. “We reduce the soluble organic fraction [by removing] the hydrocarbons and the liquid portion of the diesel exhaust,” says Desmond Gallant, sales manager of Mississauga, Ontario-based Nett Technologies, a manufacturer of emission control products. These units are “built for equipment with existing exhaust problems and need a replacement muffler.”

It is important to realize that some older engines may need more than just a catalytic converter or hydrocarbon trap to clean them up. Some of them will have to go. “If you're putting this on because you have an engine problem, we won't sell it to you,” Gallant says.

For some, an early retirement may be inevitable. Planning ahead and acting now will mean early retirement for the equipment rather than the equipment owner.

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