KNOWN ALL MEN BY THESE PRESENTS that I, Richard L. Thomas do hereby appoint Frank M. Clark and J. Barry Mitchell, or
either of them, attorney for me and in my name and on my behalf to sign the annual Securities and Exchange Commission report
on Form 10-K for 2005 of Commonwealth Edison Company, together with any amendments thereto, to be filed with the
Securities and Exchange Commission, and generally to do and perform all things necessary to be done in the premises as fully
and effectually in all respects as I could do if personally present.
/s/ Richard L. Thomas
Richard L. Thomas