Plastics and chemicals producer Nova Chemicals Corp. said second-quarter net income plunged by 78 percent in part because of a charge related to rising energy prices.

Nova, which is incorporated in Calgary, Canada, and has its executive operations in Moon, said net income fell to $18 million, or 21 cents per share, from $80 million, or 96 cents per share in the 2007 second quarter.

Analysts polled by First Call/Thomson Financial projected earnings of 22 cents per share.

Sales jumped to $2.2 billion from $1.7 billion a year ago, beating analysts' estimates of $1.94 billion.

Net income included an after-tax charge of $61 million that reflected a decline in value of its fuel contracts for a plant in Corunna, Ontario. The soaring price of crude oil outpaced price increases in Nova's contracts for butane and propane for that facility, resulting in the noncash charge. Adjusted net income was $83 million, or $1 per share, down from $84 million, or $1 per share a year ago.

The after-tax charge that reduced net income "masked the strength" of Nova's performance during the quarter, said Jeffrey Lipton, chief executive. He had disclosed the charge in a call with analysts earlier this month.

Adjusted earnings before interest, taxes, depreciation and amortization (EBITDA) totaled $258 million, "the highest second quarter in our history," Mr. Lipton said. Adjusted EBITDA was up from $251 million in the second quarter a year ago.

Mr. Lipton said he expects a stronger second half because of higher prices and continued benefits of the "Alberta advantage," which reduces Nova's production costs. Because the company utilizes cheaper Canadian natural gas at its western Canadian polyethylene facilities, its costs were 17 cents per pound lower than competitors on the U.S. Gulf Coast during the second quarter, the company said.

Shares in Nova closed at $25.08, down $1.33.