It’s a problem that has long thwarted wave energy pioneers – how to transform the slow back and forth motion of waves into a reliable and cost-effective stream of electricity.
Now two Edinburgh firms – Artemis Intelligent Power and Quoceant – have together secured £2.5 million in funding from the Scot-Govt. to test a prototype which aims to do just that.
They have developed a technology which includes the use of digital displacement hydraulics to harness the massive but slow and erratic power output of wave energy machines.
Artemis now plans to build and demonstrate a complete hybrid power transmission on a laboratory test-rig which will simulate the behaviour of a wave energy converter responding to a range of different real sea conditions.
Artemis, which was bought by Mitsubishi Heavy Industries in 2010, already uses elements of the same technology to power the world’s largest floating offshore wind turbine, which is currently operating 20 km offshore of Fukushima in Japan, for which it was awarded the MacRobert Prize in 2015 – the UK’s highest award for engineering innovation.
The new innovation has been developed in tandem with engineering consultancy Quoceant, whose team pioneered the ill-fated Pelamis wave energy device.
The Quoceant system combines the efficiency and power handling capability of the Pelamis wave energy converter with the fine control capability of Artemis’ Digital Displacement® technology.
The resulting hybrid system allows continuous and highly responsive four-quadrant load control, with the ability to absorb energy from the wave energy converter at peak powers that are more than an order of magnitude greater than the average, whilst maintaining overall conversion efficiencies above 70% in realistic ocean wave environments.
Dr Niall Caldwell, Managing Director of Artemis, said: “The core technology we will develop in our project also has wider application in large established markets worldwide.
“This can be wherever mechanical power needs to be efficiently controlled – from excavators to trains to heavy trucks – where it can dramatically lower the fuel consumption at a much lower cost than electric hybrid drives.”