HOLYOKE, Mass. – New England’s power plants are responding properly to economic incentives, and the region’s new wholesale electricity market is working well, power grid officials said Friday.

New England consumers also have more electricity generation available than they did five years ago, according to a report by ISO New England, which operates the regional power grid.

The report, which analyzed data from 1995 to 2000, said power plant owners are, on the average, producing more electricity when demand is highest and shutting down for maintenance when demand is least.

“The improvement indicates that the market is working as designed,” said Stephen G. Whitley, ISO New England’s senior vice president and chief operating officer.

New England’s wholesale electricity market opened in May 1999. It was created to make electricity generation and sales more efficient by forcing utilities to respond to signals such as market price and consumer demand.

ISO is an independent, not-for-profit corporation approved by federal regulators to manage New England’s power grid.

The report did not entirely answer questions about whether power plant companies that control much of the market have reduced output to drive up prices.

That topic will be addressed in a separate report, commissioned by Massachusetts Attorney Thomas Reilly and the Maine Public Utilities Commission, that is due out toward the end of this year.

Whitley repeated ISO predictions that New England would not face California-style blackouts this summer, when electricity demand is at its highest, because nine new power plants have begun operation this year.

But he warned that some “transmission bottlenecks” were already developing in Maine, Rhode Island, and southeastern Massachusetts, where ample supply is available but there are not enough transmission lines to carry it.

ISO New England planned to look into beefing up existing transmission lines or other ways to alleviate the bottlenecks, Whitley said.