Brace, who joined Northland in 1988 shortly after it was founded, will continue to serve as a company director, the developer added.
He had held various positions in risk management, development, construction and operations, before being appointed CEO in 2005.
During his time at Northland, the company has expanded its portfolio to include just over 2GW of operating generation capacity, including roughty 400MW of onshore wind in Canada.
Crawley, meanwhile, joined the Canadian developer in 2015, having previously been CEO of independent renewable power producer Aim Powergen, overseeing its sale to renewables developer GDF Suez Canada (then International Power), where he would later serve as president.
Since Crawley has been at Northland, the company invested in the €1.3 billion 252MW Deutsche Bucht (DeBu) offshore wind site off Germany and secured grid capacity for 300MW from its Hai Long 2 offshore wind project off the coast of Taiwan.
It also owns stakes in the 600MW Gemini site in the Netherlands, and the Nordsee cluster in Germany.