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EXHIBIT 5.4

CONSENT OF INDEPENDENT PETROLEUM ENGINEER

We hereby consent to the use and reference to our name and reports evaluating (i) a portion of Cenovus Energy Inc.'s oil and gas reserves data, including estimates of proved reserves and probable reserves and related future net revenue as at December 31, 2014, estimated using forecast prices and costs, and (ii) the contingent resources and prospective resources of Cenovus Energy Inc. as at December 31, 2014, estimated using forecast prices and costs, and the information derived from our reports, as described or incorporated by reference in Cenovus Energy Inc.'s Registration Statement on Form F-10.

MCDANIEL & ASSOCIATES CONSULTANTS LTD.

/s/ P.A. WELCH

P.A. Welch, P. Eng.
President & Managing Director

Calgary, Alberta
February 17, 2015

2200, Bow Valley Square 3, 255 – 5 Avenue SW, Calgary AB T2P 3G6 Tel: (403) 262-5506 Fax: (403) 233-2744 www.mcdan.com

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EXHIBIT 5.4

CONSENT OF INDEPENDENT PETROLEUM ENGINEER