Dr Roberts is to leave on 19 September to "pursue career opportunities outside the company". He had a two-year rolling contract and a remuneration package worth pounds 248,000 a year, according to the last published accounts. He has no immediate plans but City sources said his expertise could well secure him a job with a dozen or more US or European power generators looking to expand internationally.
Dr Roberts, 52, is almost the last survivor of the pre-privatisation management. He was mainly responsible for setting up the UK trading operations in the aftermath of privatisation a decade ago and established a reputation as a shrewd player of the internal market for electricity in the UK. But his main role recently has been to act as a link between managing director Derek King and the international businesses.
The point has now been reached, the company claims, where these businesses need a measure of independence while reporting directly to Mr King, who took over the role last year and initiated an extended clear-out of the surviving members of the board from pre-privatisation days. Dr Roberts has now effectively worked himself out of a job and the company is now in a position to take out a level of management.
City sources pointed to the problems that PowerGen's existing Australian project, Yallourn in Victoria, was facing as a result of deregulation and a fall in the wholesale electricity prices. But analysts said that rival ventures had faced similar problems and doubted if Dr Roberts could properly be blamed for its poor performance.
The company under Mr King's hands-on style of management has now purged the old board with the single exception of the chairman, Ed Wallis. This has caused some nervousness among investors but his position as Mr PowerGen remains secure, industry sources said yesterday.