The Tennessee Valley Authority Board of Directors reached its full nine-member capacity Thursday when four business and academic leaders appointed by President Barack Obama were sworn into office.

Joining the board are: William B. “Bill” Sansom of Knoxville, Tenn., who was reappointed; Barbara S. Haskew of Chattanooga, Tenn.; Marilyn A. Brown of Atlanta, Ga., and Neil McBride of Oak Ridge, Tenn. They join Chairman Dennis Bottorff of Nashville, Tenn.; William Graves, of Memphis, Tenn.; Mike Duncan of Inez, Ky.; Howard Thrailkill of Huntsville, Ala., and Tom Gilliland of Blairsville, Ga.

The ceremony was held at TVA headquarters in Knoxville, where Bottorff and U.S. Sen. Lamar Alexander, co-chair of the TVA Congressional Caucus, spoke about TVA’s mission and legacy.

“The new board members face a challenge that is critical to job growth: providing large amounts of reliable, clean electricity at a competitive cost,” Alexander said. “I applaud its mission to do this by leading the country in new nuclear power and making the air cleaner and leading the region in improvements in the efficient use of electricity.”

Bottorff said, “The four nominees joining the board today bring a diversity of knowledge and leadership skills that will help TVA continue to provide the energy and resource management services this region needs to sustain our quality of life, to protect the environment we all cherish and to keep our region competitive, nationally and globally.”

Sansom served on the TVA Board from 2006 to 2009 and was chairman from 2006 to 2008. He is chairman and chief executive officer of The H.T. Hackney Co. in Knoxville. His new term expires May 18, 2014.

Haskew recently retired from Middle Tennessee State University, where she was a distinguished professor of economics for eight years and provided leadership for more than 20 years as chair of the Department of Economics and Finance, dean of the College of Business Administration, vice president and provost of the university. She worked for TVA in the 1980s, helping develop rate structures for power distributors and industrial customers. Her term expires May 18, 2014.

Brown is a professor of energy policy at Georgia Institute of Technology’s School of Public Policy and a distinguished visiting scientist at Oak Ridge National Laboratory. Her term expires May 18, 2012.

McBride is general counsel with the nonprofit Legal Aid Society of Middle Tennessee and the Cumberlands. He also is an adjunct professor at the University of Tennessee College of Law. His term expires May 18, 2013.