Exhibit 3.1





|                                                     |                                            |                                   |  |     |                                    |                                           |             | 
|---------------------------------------------------- | ------------------------------------------ | --------------------------------- |  | --- | ---------------------------------- | ----------------------------------------- | ----------- | 
|LOGO                                                 |                                            | Prescribed byJ. Kenneth Blackwell |  |     |                                    | Expedite this Form:(Select One)          
|                                                     | Ohio Secretary of State                    |                                   |  |     | Mail Form to one of the
Following:
|                                                     | Central Ohio: (614) 466-3910               |                                   |  |     | OYes                               |                                           | PO Box 1390
|                                                     | Toll Free: 1-877-SOS-FILE (1-877-767-3453) |                                   |  |     |                                    | Columbus, OH 43216                       
|                                                     |                                            |                                   |  |     |                                    | *** Require an additional fee of $100 ***
|www.state.oh.us/sos e-mail:  busserv@sos.state.oh.us |                                            |                                   |  | ÄNo |                                    | PO Box 1028  Columbus, OH 43216          

Certificate of Amendment by

Shareholders or Members

(Domestic)

Filing Fee $50.00



(CHECK ONLY ONE (1) BOX)

|                        |  |              |  |                         |  |           
|----------------------- |  | ------------ |  | ----------------------- |  | ----------
|(1) Domestic for Profit |  |              |  | (2) Domestic Non-Profit |  |           
| ̈Amended                |  | x  Amendment |  |  ̈Amended                |  |  ̈Amendment
|(122-AMAP)              |  | (125-AMDS)   |  | (126-AMAN)              |  | (128-AMD) 





|                                                                                                                                                                                                                  |  |                                      |  |       
|----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------- |  | ------------------------------------ |  | ------
|Complete the general information in this section for the box checked
above.                                                                                                                                       |  |                                     
|                                                                                                                                                                                                                  | 
|Name of Corporation                                                                                                                                                                                               |  | The Cincinnati Gas &
ElectricCompany
|                                                                                                                                                                                                                  |  |                                     
|Charter Number                                                                                                                                                                                                    |  | 47309                                |  |       
|                                                                                                                                                                                                                  |  |                                     
|Name of Officer                                                                                                                                                                                                   |  | Richard G.
Beach                     |  |       
|                                                                                                                                                                                                                  |  |                                     
|Title                                                                                                                                                                                                             |  | Assistant
Secretary                  |  |       
|                                                                                                                                                                                                                 
| ̈Please check if additional provisions attached.                                                                                                                                                                 
|                                                                                                                                                                                                                 
|The above named Ohio
corporation, does hereby certify that:                                                                                                                                                      
|                                                                                                                                                                                                                  | 
| ̈A meeting of the ̈shareholders ̈members was duly called and held on                                                                                                                                                |  | __________________                  
|                                                                                                                                                                                                                  |  |                                      |  | (Date)
|                                                                                                                                                                                                                 
|at which meeting a quorum was present in person or by proxy, based upon the
quorum present, an affirmative vote was cast which entitled them to exercise  % as the voting power of the
corporation.              
|                                                                                                                                                                                                                 
|x In a writing signed by all of the    x shareholders ̈members who would be entitled to the notice of a meeting or such other proportion not less than a majority as the articles
of regulations or bylaws permit.





|                                                                                                                                                                                                         |  | 
|-------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------- |  | 
|Clause applies if amended box is checked.                                                                                                                                                                |  | 
|                                                                                                                                                                                                        
|Resolved, that the following amended articles of incorporations be and the same are hereby adopted to supercede and take the place of the existing
articles of incorporation and all amendments thereto.





---

|                                                                                                                                                |  |                                                                                                                                                                                  |  |         
|----------------------------------------------------------------------------------------------------------------------------------------------- |  | -------------------------------------------------------------------------------------------------------------------------------------------------------------------------------- |  | --------
|All of the following information must be completed if an amended box is checked. If an amendment box is checked, complete the areas that apply. |  |                                                                                                                                                                                 
|                                                                                                                                                | 
|FIRST:                                                                                                                                          |  | The name of the corporation
is:Duke Energy Ohio, Inc.                                                                                                                           
|                                                                                                                                                | 
|SECOND:                                                                                                                                         |  | The place in the State of Ohio where its principal office is located is in the City of:                                                                                         
|                                                                                                                                                |  |                                                                                                                                                                                 
|                                                                                                                                                |  | Cincinnati                                                                                                                                                                       |  | Hamilton
|                                                                                                                                                |  | (city, village or township)                                                                                                                                                      |  | (county)
|                                                                                                                                                |  |                                                                                                                                                                                 
|THIRD:                                                                                                                                          |  | The purposes of the corporation are as follows:                                                                                                                                  |  |         
|                                                                                                                                                |  | The Company is engaged in the production, transmission, distribution and sale of electricity and the sale and transportation of natural gas in the southwestern portion of
Ohio.
|                                                                                                                                                | 
|FOURTH:                                                                                                                                         |  | The
number of shares which the corporation is authorized to have outstanding
is:    89,663,086                                                                                  
|                                                                                                                                                |  | (Does not apply to box
(2))                                                                                                                                                     



|                                                                                           |                                                                 |                           |  |  |      |        
|------------------------------------------------------------------------------------------ | --------------------------------------------------------------- | ------------------------- |  |  | ---- | -------
|REQUIRED Must be authenticated (signed) by an authorized representative (See Instructions) |                                                                 | /s/ Richard G. Beach      |  |  |      | 9-14-06
|                                                                                           | Authorized Representative Richard G. Beach, Assistant
Secretary |                           |  |  | Date
|                                                                                           |                                                                 |                           |  |  |     
|                                                                                           |                                                                 |                           |  |  |      |        
|                                                                                           |                                                                 | Authorized Representative |  |  |      | Date   
|                                                                                           |                                                                 |                           |  |  |      |        
|                                                                                           |                                                                 | Authorized Representative |  |  |      | Date