While the author of this article is correct that it is likely Dr. Brown's nomination is being help up on political grounds the remainder of the article is almost entirely off base.
First off, it is simply inflammatory to write that the senators want a "white man". There is no proof to back up this claim and it does not belong in a profession article. Secondly, the argument that they want a buisnessman doesn't seem to cast them in a negative light. TVA is a multibillion dollar buisness that affects all of our lives and should be run by people who have experience in buisness. While Dr. Brown's credentials are impressive she has no buisness experience. If a utility executive were put on the board of a climate change panel people would be outraged. Why are they not similarily outraged that a member of a climate change panel is being nominated to run a utility. Dr Brown is no more suited to run TVA than Bill Sansom is to run the IPCC.
Furthermore, attacks on TVA's generating fleet are lacking in historical context. It is true that TVA's largest source of electricity is coal, however the last coal plant came online 40 years ago. At that point in time no one here had ever even heard the term "global warming" and it is only in hindsight that the construction of these plants seems like a poor decision. Since that time TVA has only built non-carbon emitting nuclear plants and lower carbon emitting natural gas plants. This trend continues at TVA along with their increasing purchases of wind power. TVA has a schedule to retire their old coal plants, however they cannot simply be "turned off" all at once as this would result in a lack of power as well as billions of dollars we would have to pay in order to build new generating plants. Given the lack of any suitable wind power resources in the Tennessee Valley that leaves TVA with four generating options. Wind purchases, energy efficiency, nuclear and natural gas. TVA is currently aggressively pursuing all of these options to replace their coal plants. It is easy for the author of this article and others to chide TVA for their failings, but I have yet to see anyone propose a better solution.