David Walker New CEO of DNV KEMA Energy & Sustainability PR Newswire ARNHEM, The Netherlands, June 12, 2012 ARNHEM, The Netherlands, June 12, 2012 /PRNewswire/ -- David Walker (56)will be appointed Chief Executive Officer (CEO) of DNV KEMA. He joins from the position of Chief Strategy Officer for the DNV Group. Chairman of the N.V.