Fork it over

May 1, 2002 By    

New federal regulations aimed at reducing air pollution are likely to have a significant impact on propane-fueled forklifts, including large reductions in per-unit fuel consumption.



Forklifts are the one major category of motor vehicles strongly dominated by propane motor fuel use. As much as 80 percent of the domestic heavy-duty industrial forklifts run on propane. Some estimate market domination of up to 95 percent in the future, although improved battery technology and cleaner gasoline and diesel fuel are giving other fuels competitive traction.

Last September, the U.S. Environmental Protection Agency finalized its proposed emissions rules for heavy duty, spark-ignited, off-road engines, including 40 pages of regulations for forklift engines. Final adoption of the regulations is expected in September 2002.

The text of the rules may be downloaded from the Internet.

The agency set the stage for its rulemaking by declaring that emissions from the kind of non-road spark-ignited engines used in forklifts “endanger public health.”

The new standards target industrial spark-ignition engines rated above 19kW (25 hp) and include generators as well as forklifts. The EPA proposal also will set limits for the first time on emissions from gasoline-fueled recreational vehicles including snowmobiles, off-road motorcycles and marine engines, including diesel and all stern-drive and inboard engines.

These types of off-road engines are responsible for 2 percent each of the NOX and hydrocarbon emissions from all mobile sources nationally. They also account for 3 percent of CO and two-tenths of 1 percent of all particulate pollution from mobile sources. Combined, the entire group is estimated to contribute 11 percent of current hydrocarbon emissions, 9 percent of carbon monoxide, and 3 percent nitrogen oxides.

EPA is targeting forklift emissions because of projections that in 20 years their CO output could reach as much as 8 percent of the total contamination from all mobile sources. That larger share is expected to emerge as they not only become more numerous, but other vehicle types – especially on-road vehicles of all sizes – are subjected to ever-more-stringent emissions restrictions.

EPA proposes to follow a model adopted in California by the Air Resources Board in 1998. Those standards limit forklift emissions to a maximum of 4g/kW hr (3 g/hp-hr) for hydrocarbons and NOX, and 50 g/kW hr (37 g/hp hr) for CO. EPA asked for comment on more stringent standards for 2007 that would emphasize reduction of carbon monoxide (CO) or non-methane hydrocarbons and nitrogen oxides (NOX). The former is considered more important for indoor applications, since prolonged exposure to CO can be deadly to humans.

The number of spark-ignited forklifts at work in the United States is expected to exceed 600,000 by 2007. Of those, 95 percent will be propane or CNG.
The number of spark-ignited forklifts at work in the United States is expected to exceed 600,000 by 2007. Of those, 95 percent will be propane or CNG.

The CARB rules require 25 percent of each manufacturer’s 2001 model year forklifts to meet the cleaner emissions standards. That percentage rises to 50 percent this year, 75 percent in 2003, and culminates at 100 percent compliance in 2004.

Fuel Savings

EPA had estimated that closed-loop technology, catalysts and other modifications to forklifts might increase the cost to the end user by up to $1,000. The current soft economy and the relatively small, highly competitive forklift market seems to have made manufacturers less likely to try to pass their costs along, however.

“In addition to controlling emissions, these emission-control technologies can significantly reduce fuel consumption,” an EPA notice declared. “In a high-use application, the fuel savings can fully offset the increased price for the emissions controls within one year or less.”

In fact, tamper-proof fuel systems could easily cut fuel use by 20 percent, according to Vlad Ulmer, a senior research engineer at the Southwest Research Institute in San Antonio. Ulmer has field experience installing more than 100 such systems on forklifts. He also tested forklift trucks with and without a closed-loop system for the EPA.

Ulmer says a 20 percent fuel savings with closed-loop systems is a realistic estimate, noting that forklifts typically operate with an extremely rich mix and receive very little maintenance.

Another senior research engineer at Southwest, Jim Carroll, says that the typical forklift is often set to “idle” with a wide open throttle. Settings that are lean for carbon monoxide (CO) typically put NOX emissions higher, he adds. Closed-loop systems counter these tendencies by “keeping an ideal all the time.”

One obstacle to maintaining low emissions is tampering with under-the-hood settings.

“All the forklift drivers think they are Formula One drivers,” Ulmer says with good-humored exasperation. “I haven’t seen one truck that was set to lean.”

EPA projects a 20 percent increase in the number of units operating nationally by 2007. By EPA estimates, that would mean the overall forklift fuel load will remain pretty much at present-day levels.

The Market

About 150,000 large spark-ignition engines are sold in the United States annually. With so many manufacturers in the marketplace and no one manufacturer achieving dominant market share, sales volumes by each company tend to range from 10,000 to 25,000 units annually, according to the U.S. EPA.

The agency has used varying estimates of the nation’s total number of forklifts. By one estimate, there were 247,543 spark-ignited forklifts operating in the United States in 2000. The air pollution watchdog agency projected a forklift population of 297,973 by 2007 – an increase of more than 20 percent in just seven years.

But Allen Stout, a mechanical engineer in the Assessment and Modeling Division of EPA in Ann Arbor, Mich., estimates there were 504,696 spark-ignited forklifts in the nation in 2000 and projected 603,099 by 2007. Of those, 95 percent will be LPG or CNG.

He added that propane continues to have a competitive edge over CNG because “the cost of installing high-pressure refueling equipment is an obstacle to increased use of natural gas systems.”

Other studies also suggest that the fastest growth in forklifts in the next decade will be in propane-fueled units, as sales of gasoline forklifts diminish due to higher CO pollution from gasoline engines.

The Industrial Truck Association, a national organization representing forklift manufacturers, recognizes seven classes of forklifts. The first three are electric lifts including hand trucks.

Class 4 forklifts are internal combustion powered sit down lifts with cushion tires, generally used indoors on hard floors.

Class 5 lifts are internal combustion powered sit down forklifts with pneumatic tires, typically used outdoors, on rough surfaces, or significant inclines.

Class 6 can be electric or internal combustion driven, and are ride-on units that can tow at least 1,000 pounds, rather than lift it.

Classes 4 to 6 have typically been where the majority of propane-powered, spark-ignited forklifts and airport tow vehicles have been deployed.

Class 7 trucks, usually diesel-powered, are outdoor, rough terrain forklifts with pneumatic tires.

Electric forklifts are generally more expensive than propane models, and have been less powerful. CARB estimated 70,000 electric lifts in that state, about 71 percent of which were small (Class 3) hand trucks and narrow aisle trucks.

A Gas Research Institute study cited by CARB says the average time an internal combustion forklift is operated is 1,900 hours per year. Electric lifts, which include small electric handtrucks, average about 2,250 hours per year, it said. Both average 1.5 shifts per day, five days per week.

GRI found that 69 percent of Class 1 and 2 electric forklifts were operated only one shift per day, 16 percent two shifts, and 15 percent three shifts. Typically they were recharged after 11 clock (not service) hours. For internal combustion engines, 59 percent operated only one shift daily, while almost 40 percent operated two shifts.

GRI found everything from continual use to as little as four hours per shift. The average propane tank is replaced or refilled after 15 hours, according to the research.

That market data also suggested that approximately 55 percent of forklifts of all types are owned by the end user. An estimated 30 percent are full-service leases, while 15 percent are short-term rentals.

The Dealers

Forklift manufacturers are hardly overwhelmed by the new market. Of those contacted, only one said that it was offering new, improved, CARB-mandated lower emissions forklifts at a price higher than the previous year’s less efficient models.

Dale Muhlenkamp, dealer training and customer support manager at Toyota Material Handling, U.S.A. in Torrance, Calif., said that Toyota was shipping only low-emissions Class 4 and 5 forklifts to California. The primary emissions reduction strategy in use on Toyota’s 2001 California models is a three-way catalyst and an oxygen sensor in the tailpipe.

Muhlenkamp says the greatest challenge was not hitting the targeted emissions numbers, but making the emissions control equipment fit into the small engine spaces. In fact, an emissions reduction package for Toyota forklift products was developed eight or 10 years ago and offered as an option on pneumatic trucks. At that time, it was “priced out of reach and we did not sell any significant volume,” he says.

He declined to discuss product pricing.

Toyota’s cleaner forklifts are available nationwide. Muhlenkamp believes that there are ISO 14000-certified businesses in the United States that may want them.

Companies certified to the ISO 14000 standard have committed to conducting business in a manner that is sensitive to environmental management issues. Participants in that international standardization program set environmental objectives and undergo periodic audits of their environmental plans and applications.

Muhlenkamp estimates that the total annual U.S. market for Class 4 And 5 forklifts is about 80,000 units. As many as 12,000 of those are larger, diesel-fueled units. Forklift classes 1-3 are heavily dominated by electrics, which constitute about 57 percent of total forklift sales. That leaves about 68,000 new propane forklifts sold domestically each year.

Toyota makes a 48-volt, pneumatic electric forklift that Muhlenkamp says gets close to the performance of propane-fueled units in Classes 4 and 5. “But pneumatic electrics have not been a U.S. market. All we try to do is what the customer wants.”

For the moment, that means marketing to the industrial truck customer a cleaner propane forklift that can meet the new emissions requirements, and efficiently get the load-moving work done at the warehouse or in the factory.

Workplace Worries

Workplace air contamination limits adopted by the Occupational Safety and Health Administration may also be stimulating some interest in cleaner forklifts. OSHA requires workplace carbon monoxide be held to under 50 parts per million, over an eight-hour day. Plant managers, not engine or equipment manufacturers, are responsible for meeting those limits.

“Concerns for high indoor pollution concentrations have created a small but distinct demand for aggressive emissions controls on forklifts,” EPA said in a public notice in 2000.

But one marketing manager for a smaller manufacturer says he does not find companies demanding cleaner forklifts.

“This is not customer-driven,” he says. “We don’t have people calling up and saying, ‘I want one of your clean engines.’ “

As the federal regulatory effort on forklifts has unfolded, the National Propane Gas Association has criticized the more stringent standard that California has adopted for propane used as forklift fuel.

The current national HD-5 motor fuel specification for propane is criticized by CARB and some vehicle manufacturers as allowing too much unspecified material that can turn to sludge within an engine, potentially impairing performance.

Phil Squair, NPGA’s director of Regulatory Affairs, has filed comments with the EPA opposing stricter fuel standards on the national level.

“A lot of the push for fuel specs came from the manufacturers of equipment,” Squair said. “But there’s no real data that shows that it’s a problem for emissions purposes.”

Mike Caldarera, NPGA’s manager of regulatory technical services, says the industry has taken the position that “they can meet the emissions standards with the fuel that is available,” and that a more stringent standard would be “difficult to do” from a supply standpoint. Fuel standards expected to be in place by 2007 are likely to be more stringent.

Caldarera says the propane forklift market is important to the industry, and one well worth defending.

“It’s a niche market, but it’s a good market that we have a good handle on.”

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