**Exhibit 31.a**

**CERTIFICATIONOF THE CHIEF EXECUTIVE OFFICER**

**PURSUANTTO SECTION 302 OF THE SARBANES-OXLEY ACT OF 2002**

I, David L. Hauser,certify that:

1. I have reviewed this quarterlyreport on Form 10-Q of Cinergy Corp.;

2. Based on my knowledge,this report does not contain any untrue statement of a material fact or omit tostate a material fact necessary to make the statements made, in light of thecircumstances under which such statements were made, not misleading withrespect to the period covered by this report;

3. Based on my knowledge,the financial statements, and other financial information included in thisreport, fairly present in all material respects the financial condition,results of operations and cash flows of the registrant as of, and for, theperiods presented in this report;

4. The registrant’s othercertifying officers and I are responsible for establishing and maintainingdisclosure controls and procedures (as defined in Exchange Act Rules 13a-15(e)and 15d-15(e)) and internal control over financial reporting (as defined inExchange Act Rules 13a-15(f) and 15d-15(f)) for the registrant and have:

a)Designed such disclosure controls and procedures, or caused such disclosurecontrols and procedures to be designed under our supervision, to ensure thatmaterial information relating to the registrants, including their consolidatedsubsidiaries, is made known to us by others within those entities, particularlyduring the period in which this report is being prepared;

b)Designed such internal control over financial reporting, or caused suchinternal control over financial reporting to be designed under our supervision,to provide reasonable assurance regarding the reliability of financialreporting and the preparation of financial statements for external purposes inaccordance with generally accepted accounting principles;

c)Evaluated the effectiveness of the registrant’s disclosure controls andprocedures and presented in this report our conclusions about the effectivenessof the disclosure controls and procedures, as of the end of the period coveredby this report based on such evaluation; and

d)Disclosed in this report any change in the registrant’s internal control overfinancial reporting that occurred during the registrants’ most recent fiscalquarter (the registrant’s fourth fiscal quarter in the case of an annualreport) that has materially affected, or is reasonably likely to materiallyaffect, the registrant’s internal control over financial reporting; and

5. The registrant’s othercertifying officers and I have disclosed, based on our most recent evaluationof internal control over financial reporting, to the registrants’ auditors andthe audit committee of the registrant’s board of directors (or personsperforming the equivalent functions):

a) Allsignificant deficiencies and material weaknesses in the design or operation ofinternal control over financial reporting which are reasonably likely toadversely affect the registrant’s ability to record, process, summarize andreport financial information; and

b) Anyfraud, whether or not material, that involves management or other employees whohave a significant role in the registrants’ internal control over financialreporting.

 
| Date:  August 11, 2006 | /s/    | David L. Hauser         |
|-----------------------------|--------|-------------------------|
|                        |   | David L. Hauser         |
|                        |   | Chief Executive Officer |

 

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