WARWICK - National Grid is willing to return to the negotiating table with offshore wind farm developer Deepwater Wind, the state's largest utility said in a filing with the R.I. Public Utilities Commission (PUC).

The Wednesday filing, actually a copy of a letter sent to Deepwater, came six days after National Grid rejected the developer's renewable energy contract offer, saying that electricity from Deepwater's proposed offshore wind farm would be too expensive. Deepwater maintained in interviews and a subsequent filing with the PUC that National Grid misunderstood the proposal.

In an Oct. 21 letter to Deepwater CEO Bill Moore, National Grid's Director of Wholesale Market Relations Madison N. Milhous Jr. said the company "read with interest reports in the news media that you believe that the price for the power would be between 20 and 25 cents per kilowatt-hour" as opposed to Grid's conclusion that the cost would be 30.7 cents a kilowatt-hour.

Milhous said if Deepwater is truly pitching a fixed price of 20 cents to 25 cents a kilowatt-hour in the first full year of operation in 2013, then "Grid would be interested in meeting with you again." Milhous said Grid also wants assurances that Deepwater is offering a fixed-rate contract and that the utility would pay only for electricity actually produced without a revenue make-up provision in later years to compensate for lost revenue that might happen if, say, the wind is not blowing.

"National Grid believes that renewing negotiations could be fruitful," Milhous wrote. "While we cannot promise that we would necessarily support a new proposal at the stipulated pricing, given the fact that 20 to 25 cents per kilowatt-hour is still quite high, we certainly would consider and evaluate it. Of course, there are other important issues that would need to be addressed in negotiations as well, but the issue relating to fixed pricing is a threshold issue."

The PUC is scheduled to discuss the issue Thursday afternoon. The commission could continue the matter or force the two sides into arbitration.

The PUC gained oversight over the matter after the General Assembly passed a law earlier this year. The law requires National Grid to procure some of its electricity from renewable sources and left it to the PUC to approve a "commercially reasonable" contract between a renewable energy provider and the utility. Deepwater was the sole bidder to fulfill that contract.