Shell joins developers Vattenfall, EnBW, Ørsted, E.on, Equinor, Innogy, SSE and Iberdrola-owned ScottishPower Renewables in the programme that supports research and development in new technologies for the offshore wind market.
The accelerator, launched in 2008, focuses on five research areas: access, cables, electrical systems, wake effects and foundations.
The programme has helped develop lighter monopile foundations through the Pile Soil Analysis (PISA) project and bring 66kV cables to the market.
The accelerator is also working on three-dimensional wind mapping of potential project sites, and has supported work on floating lidar and suction bucket foundations.
"The Carbon Trust's Offshore Wind Accelerator is a good example of the collaboration required between public and private sectors.
"The research and development programme will be key to delivering technical, commercial and financial innovations for large scale and sustainable offshore wind opportunities in the future," said Dorine Bosman, vice president of wind development at Shell.
Jan Matthiesen, director at the Carbon Trust, added: "It is great news for the programme to have yet another strong and ambitious partner on board. It demonstrates that the collaborative approach to R&D in offshore wind is valued by the industry."
The programme is part funded by the Scottish government and the industry partners.
Shell has made a number of moves in the offshore industry in the last two years, notably being part of the consortium developing the 700MW Borssele III & IV site off the Netherlands.