Steve Lucas, the finance director of energy pipeline grid operator National Grid is to retire from the board at the end of this year.The company said his replacement will be Andrew Bonfield, who will take over as finance director on 1 November.Bonfield was chief financial officer of confectionery group Cadbury when it was taken over in March of this year by US processed foods giant Kraft Foods. He is currently a non-executive director at DIY retailer Kingfisher.Prior to his stint at Cadbury he was vice-president and chief financial officer at Bristol-Myers Squibb for five years, based in New Jersey, US. Previously, Andrew was the Finance Director at BG Group and chief financial officer at SmithKline Beecham and was a non-executive director of BOC Group.