Lift Truck Fuel Systems Can Meet 2007 EPA Standards

July 1, 2004
The Propane Education & Research Council (PERC) announced that initial test results of propane fuel control systems being tested at the Southwest Research

The Propane Education & Research Council (PERC) announced that initial test results of propane fuel control systems being tested at the Southwest Research Institute (SwRI) are able to meet 2007 EPA standards for both steady-state and transient operating conditions. Test results of the fuel systems found that they produced readings for hydrocarbons (HC) plus nitrogen oxides (NOx) that were within the 2007 EPA standards. These results were achieved using new engines and controlled fuel.

The goal of the 2007 EPA standards, based on 2001 standards established by the California Air Resources Board (CARB), is to reduce emissions from 3 g/bhp-hr to 2 g/bhp-hr as well as introduce transient testing protocol.

“In order to meet 2007 standards, lift truck engines must perform an order of magnitude better than current systems,” said Brian Feehan, executive director of the Propane Vehicle Council. “These research results are important in that they demonstrate that inexpensive fuel systems available today can achieve these new standards by using newer high-tech controllers, ensuring that propane can remain a clean and cost-effective fuel for lift trucks.”

The test results are from the first phase of a $1.39 million research study funded by the propane industry to assess fuel system technologies and fuel quality issues relative to large spark-ignited (LSI) non-road engines. The tests analyzed closed-loop carburetion incorporating three different lift truck catalysts. Tests monitored the fuel system’s air/fuel ratio, which requires precise control to meet both steady-state and transient operating conditions. Researchers are now conducting the critical durability testing on the systems.

“The Industrial Truck Association [ITA] appreciates the important work on emissions-reduction technologies being pursued by Southwest Research at the behest of PERC,” said ITA Executive Director Bill Montweiler. “The EPA emissions regulations that are scheduled to take effect in 2007 set challenging standards that engines must meet over their useful lives under actual-use conditions. The Southwest results, although based on testing new engines using controlled fuel, nonetheless represent impressive advances that reflect a substantial commitment of resources from many stakeholders. The next critical challenge will be to develop systems that can meet EPA's durability requirements under the variable conditions of actual use. We look forward to working with the propane industry in facing and meeting that challenge."

In addition to fuel technology systems, the propane industry is also studying the effects of propane fuel quality variation on emissions deterioration. Installation and set-up of the fuel blending and handling facility have been completed and propane fuel quality studies are now under way.

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