Garrad’s mission for the company was to be able to predict the weather, through the turbines and wind farms, the electricity they provided to the grid and the resulting cash flow.

[4][5] In 1984 Garrad wrote the initial version of the wind turbine system aeroelastic code Bladed, whose development continues to this day.

[6] Data, both measured and predicted, were the main currency of Garrad Hassan and the company produced many other computational tools[7][5][8] adopted by the industry.

Garrad was a member of the Council (Governing Body)[21] of the University of Bristol from 2012 to 2016 and is on the advisory board of the Cabot Institute.

[24] Garrad was appointed a Commander of the Order of the British Empire (CBE) "for services to renewable energy" in the 2017 New Year Honours.

"[31] OGM[32] named him one of the world's seven most influential energy leaders; Daily Magazine made a similar reference.

[35][36] In 2024 he and Henrik Stiesdal received the Queen Elizabeth Prize for Engineering for their work on the development of high performance wind turbines.