**Exhibit 99.5**

 

**CERTIFICATIONPURSUANT TO RULE 13a-14 OR 15d-14 OF THE SECURITIES EXCHANGE ACT OF 1934**

 

I, William E. Andrew, certify that:

 

1.               I have reviewedthis annual report on Form 40-F of Penn West Energy Trust;

 

2.               Based on my knowledge, this report does notcontain any untrue statement of a material fact or omit to state a materialfact necessary to make the statements made, in light of the circumstances underwhich such statements were made, not misleading with respect to the periodcovered by this report;

 

3.               Based on my knowledge, the financialstatements, and other financial information included in this report, fairlypresent in all material respects the financial condition, results of operationsand cash flows of the issuer as of, and for, the periods presented in thisreport;

 

4.               The issuer’s other certifying officer and I areresponsible for establishing and maintaining disclosure controls and procedures(as defined in Exchange Act Rules 13a-15(e) and 15d-15(e)) andinternal control over financial reporting (as defined in Exchange Act Rules 13a-15(f) and15d-15(f)) for the issuer and have:

 

(a)                                  Designed such disclosure controls andprocedures, or caused such disclosure controls and procedures to be designedunder our supervision, to ensure that material information relating to theissuer, including its consolidated subsidiaries, is made known to us by otherswithin those entities, particularly during the period in which this report isbeing prepared;

 

(b)                                 Designed such internal control overfinancial reporting, or caused such internal control over financial reportingto be designed under our supervision, to provide reasonable assurance regardingthe reliability of financial reporting and the preparation of financialstatements for external purposes in accordance with generally acceptedaccounting principles;

 

(c)                                  Evaluated the effectiveness of the issuer’sdisclosure controls and procedures and presented in this report our conclusionsabout the effectiveness of the disclosure controls and procedures, as of theend of the period covered by this report based on such evaluation; and

 

(d)                                 Disclosed in this report any change inthe issuer’s internal control over financial reporting that occurred during theperiod covered by the annual report that has materially affected, or isreasonably likely to materially affect, the issuer’s internal control overfinancial reporting; and

 

5.               The issuer’s other certifying officer and Ihave disclosed, based on our most recent evaluation of internal control overfinancial reporting, to the issuer’s auditors and the audit committee of theissuer’s board of directors (or persons performing the equivalent function):

 

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(a)          All significant deficiencies and material weaknessesin the design or operation of internal control over financial reporting whichare reasonably likely to adversely affect the issuer’s ability to record,process, summarize and report financial information; and

 

(b)         Any fraud,whether or not material, that involves management or other employees who have asignificant role in the issuer’s internal control over financial reporting.

 

Dated:             March 26, 2008

 
|   | /s/ William E. Andrew                                |
|--------|------------------------------------------------------|
|   |                                                 |
|   | William E. Andrew                                    |
|   | Chief Executive Officer of Penn West  Petroleum Ltd. |

 

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