Public Service's pledge was made as part of a U.S. Department of Energy program to get utilities to reduce so-called greenhouse gases.
Last week, Pennsylvania Power & Light Co., which serves the Allentown area, also signed on to the department's program and promised to reduce its carbon dioxide emissions by more than 2 million tons a year by the end of the century.
Under that pledge, the firm will reduce its annual carbon dioxide output
from about 21 million tons a year to approximately 19 million.
On average, the United States annually pumps about 5 billion tons of carbon dioxide into the atmosphere.
The notion that industrial activity, by giving off gases such as carbon dioxide, is warming the atmosphere and changing the Earth's climate is challenged by business groups and some scientists.
But most scientists are convinced the gases will cause catastrophic weather changes, and the Department of Energy's program, geared to keeping greenhouse emissions to 1990 levels, reflects that concern.
Thus, Public Service's decision to enlist in the program is important, according to officials of the Environmental Defense Fund.
"We hope it will serve as a model for other" utility companies, said Joseph Goffman, senior attorney for the Environmental Defense Fund.
Public Service says it will spend about $1 billion on its efforts.
Among other things, the utility will replace some older generators with ''cleaner, state-of-the-art equipment" capable of using natural gas, according to Neil Brown, a company representative.
Natural gas, though also a fossil fuel, results in significantly lower greenhouse-gas emissions, according to Brown.
The utility also hopes to reach its goal by showing its customers how to use less electricity.
Over the next five years, the use-less approach is expected to reduce demand for electricity by a total of one million watts, enough power to satisfy the demands of 800 residential customers over the span of a summer, according to Brown.
"We think it's important to make these environmental improvements now in the most economical way possible, rather than wait until more Draconian measures have to be taken," Brown said.
Under a memorandum signed Tuesday with the Environmental Defense Fund, the group will keep an eye on the utility's progress, largely by monitoring emission reports the Public Service has to file with the Environmental Protection Agency.
The agreement between the fund and Public Service also recognizes the environmental group's right to force, by going to court if necessary, the utility to live up to its promises, Goffman said.
But the environmental group will not just "be there like a bunch of environmental meat inspectors going thumbs up or thumbs down," Goffman said.
The agreement also calls on the Environmental Defense Fund to come up with carbon dioxide-reducing programs for the utility if Public Service's own efforts to lower emissions falter.
"To make the contract work, we have to come up with meaningful ideas of our own," Goffman said.