Aquamarine Power said its prototype wave energy device had begun producing power again after a major overhaul saw it replace a large number of failed parts.
The Edinburgh firm said the “survivability” of its flagship Oyster 800 device was well proven but it admitted that several of the systems and components on the machine had failed to stand up to long-term operations in a harsh environment.
The experimental device, which was built by Fife fabrication group BiFab, underwent a major refit over the summer and autumn period which saw it fitted with new, more durable parts to replace those which had stopped working.
The machine is now back operating at the company’s site at Billa Croo, part of the European Marine Energy Centre, in waters off Orkney.
Aquamarine said the revamped device produced its first electricity output last week and would now undergo an extensive series of tests aimed at improving operational performance and its overall reliability.
“The product improvement programme has been extremely challenging but has resulted in an even better Oyster 800,” said Aquamarine Power chief executive officer Martin McAdam.
“We have just completed a huge programme of work over the summer.
“I think someone referred to the programme as major heart surgery.
“I think that that is an exaggeration but we swapped out a large number of failed or non-functioning components.
“The machine’s survivability is already well proven. It has operated through two winters, enduring massive storms.
“The downside is that several of the systems and components on Oyster were just not fit for purpose.
“Our Product Improvement Programme (PIP) allowed us to focus on those areas which were just not up to the job, such as cabling, connectors, accumulators and several of the components of the control and instrumentation system.
“We also had some failures in the valve and pipework systems.
“We exported our first power since the refit last week and we are now running through phased testing and building up our electricity exports.”
Mr McAdam said test data for the revamped machine showed a marked improvement in performance for the 800, but he said there had been some operational issues since the relaunch.
The company is progressing developmentof a new generation Oyster 801 device but Mr McAdam said there was a lot to be learnt before Aquamarine whose key investors are ABB, SSE and Scottish Enterprise could move on.
“The most important part of the Oyster 800 programme has been the learning,” Mr McAdam said.
“Failures can be frustrating but they are not all bad, they are opportunities to learn and we have done a lot of learning.
“The team at Aquamarine Power have given the programme an extraordinary level of commitment.”
The new testing phase represents a step forward for Aquamarine after it was forced to play down fears over its finances during the summer after annual pre-tax losses spiralled to more than £35 million.
At that time, the company admitted that progress in commercialising its technologies had been slower than anticipated but said the establishment of a positive strike price for wave energy and other movement in relation to transmission charging had reduced the risk to Aquamarine and the sector as a whole.