Suncor Energy Inc.

Suncor Energy Inc.

December 19, 2006 00:00 ET

Suncor Energy reports unplanned unit shutdown at Commerce City refinery

(Financial figures are in U.S. dollars)

Denver, Colorado (December 19, 2006) — Suncor Energy (U.S.A.) Inc. reported today an unplanned shutdown of the diesel hydrotreating unit at its Commerce City refinery. This unit reduces sulfur content of diesel fuel in order to meet Ultra Low Sulfur Diesel (ULSD) requirements. The shutdown was a result of a failure in the unit's furnace.

The unit was safely taken off line during a controlled shutdown on December 15. Suncor maintenance personnel are currently determining the scope of the repair and plan to safely return the unit to full production as quickly as possible. As a result of the outage, the refinery's ULSD production is currently reduced to approximately 5,000 barrels per day from normal capacity of 20,000 bpd.

"We regret the inconvenience and are working to minimize the impact to our customers." said Steve Douglas, general manager of supply and marketing.

The refinery's diesel hydrotreating unit has been performing reliably since it began operations in June when Suncor completed a $445 million plant upgrade and began producing ULSD. As of June 1, 2006, the Environmental Protection Agency (EPA) mandated that refineries reduce the sulfur content of diesel to 15 parts per million (ppm) from 500 ppm.

This news release contains forward-looking statements that address goals, expectations or projections about the future. These statements are based on Suncor's current goals, expectations, estimates, projections and assumptions, Some of the forward-looking statements may be identified by the words "plans" "are working", "continues" and similar expressions. These statements are not guarantees of future performance. Actual results could differ materially, as a result of factors, risks and uncertainties, known and unknown, to which Suncor's business is subject. Further discussion of the risks, uncertainties and other factors that could affect these plans, and any actual results, is included in Suncor's annual report to shareholders and other documents filed with regulatory authorities.

Suncor Energy (U.S.A.) Inc. is a wholly-owned subsidiary of Suncor Energy Inc., an integrated energy company based in Calgary, Canada. Suncor Energy U.S.A.'s business includes refining operations and retail sales in the Denver area under the Phillips 66® brand, and pipeline operations in Colorado and Wyoming. Suncor's common shares (symbol: SU) are listed on the New York and Toronto stock exchanges.

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For further information, contact:
Lisha Burnett
(303) 570-2540