The tie-up is foreseen marrying Seattle-headquartered Principle Power's expertise in floating offshore wind foundations – the designer's WindFloat prototype has been turning off Portugal since mooring in 2011 – with Shell's experience installing and operating floating offshore oil and gas platforms around the world.

"It is a great privilege to welcome Shell as a technology partner," says Principle Power chief executive João Metelo.

"Shell provides our team access to an unparalleled knowledge base, crucial in realising the WindFloat as a paradigm shift, in both cost and risk, to the offshore wind industry."

Rechargerevealed yesterday (Monday) that a consortium of European and Japanese industrialists had set the seal on a plan to develop a 25MW floating wind array in the Portuguese Atlantic using Principle Power's second-generation WindFloat semisubmersible foundations.