More companies in Pa. trying fracking with gas

More companies in Pa. experiment with natural gas to power hydraulic fracturing pump engines

HARRISBURG, Pa. (AP) -- Another natural gas exploration company says it's experimenting with the gas to power huge pump engines that drive the hydraulic fracturing process.

Cabot Oil and Gas Corp. said Monday that it successfully tested an engine last month in northern Pennsylvania's Susquehanna County with gas from other wells it had already drilled.

A Cabot spokesman says the Houston-based company has two multi-engine units active in Pennsylvania's Marcellus Shale formation.

The formation is thought to be the nation's largest natural gas reservoir.

A number of increasingly cost-conscious oil- and gas-field companies are trying to save money by using natural gas to run trucks and drilling rigs.

The conversion of the hydraulic fracturing pump engines to natural gas is particularly challenging because of the amount of horsepower necessary to power the pumps.