John Sheridan took over as CEO at Ballard Power Systems in February 2006 John Sheridan took over as CEO at Ballard Power Systems in February 2006 When John Sheridan took over as CEO at Ballard Power Systems Inc. in February, 2006, he understood the Herculean task that lay ahead. Having previously served as chairman, Sheridan knew that the company's dream of putting fuel cells in every car was dead for the foreseeable future.