But in the drive to reduce the cost of offshore wind energy below the magic £100 ($167) per MWh mark, engineers are now looking to break away from reworking moored oil platforms to create lightweight giants for the richer gusts offshore.

TetraFloat is one of these. Recent wave-tank testing of the pyramidic concept, which is backed by seedcorn funding from the UK’s Department of Energy and Climate Change (Decc), suggests an initial cost of energy (CoE) of about £120/MWh, which could be further cut when scaling up for 10MW turbines.

“Offshore