and regional applications where low-emitting vehicles are mandated.
The dual fuel engines in the Cat line-up operate on a combination of diesel fuel and natural gas. Unlike all-gas engines, they have no spark ignition, but rely on the diesel combustion to ignite the natural gas. As a result, only around 15% of the fuel charge is diesel; the rest is natural gas. This allows for performance that is very similar to a diesel’s with lower emissions and better economy than spark ignited engines.
Typical users of the dual-fuel engines include the public transportation system at Disneyland, Anaheim, Calif., where 190-horsepower 3126B engines power the trams.
But the option is not limited to small engines. Harris Ranch, a feedlot operator in California’s San Joaquin Valley, has incorporated the technology into C-12 engines rated 410 horsepower. Trucks with these engines run 80,000-pound GVWs in the mountainous areas of Southern California.
Natural gas engines are California Air Resources Board certified to the 2.5 g NOx level and offer the potential to lower operating costs in areas where natural gas is abundant and inexpensive. Also, there are tax rebates to help defray costs.
To this point, the dual-fuel conversion has been done outside the Caterpillar production process at the dealers, but it will be brought on to the production line during 2001.
The 3216B also will be available starting March 1 as a Clean Diesel low-emission engines that can be used in fleets operating in emissions non-attainment areas.
With the start of production in March, the clean 3126B will reduce NOx and NMHC emissions by 13%. From July of next year that will be increased to a 22% reduction using exhaust aftertreatment.
The Cat 3126B clean diesel will be available in ratings from 175 to 330 horsepower. Additionally, three ratings – 207, 216 and 230 horsepower – will be certified to meet stricter low emissions vehicle (LEV) standards.