A wave power developer has said tests of a device off Scotland's coast exceeded expectations.
US-based Ocean Power Technologies (OPT), which also has offices in Warwick, Warwickshire, deployed the machine from Invergordon, Easter Ross.
The trials of the PB150 PowerBuoy required the consent of the Scottish government.
OPT has also been developing wave energy devices for powering US Navy and Marine Corps bases.
The tests off Scotland are mentioned in the company's latest financial results.
OPT said it had successfully deployed the PB150 PowerBuoy off the coast of Scotland on 15 April 2011.
It said initial reported power levels for the system had outperformed expectations.
OPT added: "The company believes the capacity factor represented by these results exceeded that experienced by most other renewable sources."