Engel will be based at the advisory and certification body's Dutch headquarters in Arnhem. He will take up his new role from 4 April.
Engel was sacked as Vestas CEO in August 2013, having been in the role since 2005. He proved to be a controversial figure in his latter years at Vestas as the company moved to make deep cuts and close a number of factories in order to turn around losses.
He was also embroiled in a number of legal cases involving former CFO Henrik Norremark, which were finally settled at the end of February 2016.
In 2014, it was reported Engel had joined the Big Future 2025 think-tank set up by Danish electricity supplier SE. Big Future 2025 looks at creating a sustainable future for Danish companies and help them expand using natural resources.
DNV GL said Engel was a member of "a number of senior non-executive board and advisory roles, which he will terminate in order to fully concentrate on his new position".
"I am very pleased to announce that Ditlev Engel has accepted the position as CEO of our energy business area. He has extensive knowledge of the global energy industry, which will allow him to continue to developour value proposition and services to our customers," said DNV GL group CEO Remi Eriksen.
"A key success factor will be to focus on helping customers effectively address the trilemma of affordable, accessible and sustainable energy in an increasingly complex and changing market. Impressed by DNV GL's global presence, purpose and values, I look forward to converting DNV GL's new strategy 2016-2020 into actions together with my new colleagues," Engel said on his new role.