Last month, the IRS issued guidance (Notice 2013-29) on satisfying the new “beginning of construction” requirement for the renewable energy production tax credit under Code Section 45 (PTC) and energy investment tax credit under Code Section 48 (ITC).  The IRS has revised Notice 2013-29 to provide guidance clarifying the definition of a “binding written contract,” which can be relevant for both methods of establishing the beginning of construction – performing physical work of a significant nature or satisfying the safe harbor.  (See previous blog post from April 17, 2013).