Pelastar has been developed by US-based naval architecture and marine engineering firm Glosten Associates.
The ETI's offshore renewable energy test facility, Wave Hub, has applied for consent to operate the demonstrator over a period of 10 years and hopes to have the project running as early as 2015.
The aim of the project is to accelerate the commercial application of floating foundations for wind turbines which could open up new deep water areas for deployment. The platform is designed to remain stabilised in offshore conditions by vertical-load anchors embedded in the sea floor and tensioned mooring tendons.
Andrew Scott, programme manager for offshore wind at the ETI, said: "Our modeling and engineering design projects have shown that floating offshore wind farms could play a key role in providing affordable, secure and sustainable energy for the UK as part of a broader and balanced energy system."
The ETI said it will decide in the new year whether to invest up to £21 million in the construction and deployment of the demonstrator project.