The Union Pacific Railroad plans to invest in 111 low-emissions locomotives that should help reduce pollution in Texas over the next decade.

The new locomotives, which are also more fuel-efficient, will be used in rail yards in Houston, Galveston, Dallas, Fort Worth and San Antonio. Union Pacific plans to have them in place by the middle of 2007.

The railroad said it expects these locomotives to reduce nitrogen oxide emissions by up to 80 percent while using as much as 40 percent less fuel.

"Our new low-emission yard locomotives are the next chapter in Union Pacific´s voluntary efforts to reduce emissions," said Bob Grimaila, Union Pacific´s vice president of environment and safety.

The railroad plans to use incentive money from Texas to help purchase the new locomotives. That grant also helped pay for 13 low-emission switchers from Motive Power Industries, which are powered by 2,000-horsepower Caterpillar engines.

Ninety-eight of these low-emission rail yard locomotives will be built by RailPower Technologies Corp. The units are powered by two or three 700-horsepower small diesel engines commonly used in over-the-road trucks. Each engine turns a generator that produces electricity for motors connected to the axles of the locomotive wheels.

The two-engine models are hybrid locomotives, operating both on the twin diesel engines and a bank of batteries that provides additional power.

Union Pacific has purchased more than 2,000 fuel-efficient locomotives since 2000, and about 1,000 older locomotives have been retrofitted to comply with stricter EPA standards.