That was proven to be "fake news". Essentially someone talked to a source (Michael McKenna) that hadn't even talked to Perry after his name was floated. Later

That was proven to be "fake news". Essentially someone talked to a source (Michael McKenna) that hadn't even talked to Perry after his name was floated. Later interviews with McKenna even had him saying that he was misquoted. The DoE does lots of work in Texas, and as former governor Perry had experience in working with them on managing the US's nuclear weapons stockpile. Part of his campaign platform in 2011 was to split the National Nuclear Security Administration out of the DoE and give it to the DoD. In his statement accepting the nomination, he specifically called out the role of the DoE in safeguarding the US nuclear arsenal. Otherwise don't let me stop the "hurr Durr stupid Republicans" circle jerk.