Wave power refers to the energy of ocean surface waves and the capture of that energy to do useful work - including electricity generation, desalination and the pumping of water into reservoirs.

The fundamental challenges of wave power are finding a system which converts wave motion into electricity and building affordable devices resilient enough to survive storms and salt water corrosion.

The main systems used and under development at the moment include:

• A moored pontoon which is driven by wave action to creat hydraulic power and thereby electrical energy. The Pelamis Wave Energy Converter is this type.
•  A floating bouy, which forces seawater into a turbine that drives an electrical generator.
•  A device which uses wave action to compress air in a chamber which, in turn, drives an air turbine and generator.
•  A submerged device where pressure variations from overhead waves are used to drive a piston and, thereby, a generator.

Scotland has led the world in the development of wave power, starting back in the 1970s when Professor Stephen Salter of the University of Edinburgh developed the famous "Salter's Duck".

However, a lack of funding support meant that progress was slow for 25 years. In 1995 the world's first grid connected wave device was built on Islay, again using technology from a Scottish company, Wavegen.

Nowadays there are a number of marine technology developers based in Scotland prompting hopes that the industry can secure economic benefits similar to those of wind power in Denmark, where over 30,000 jobs have been created by what is now its second largest industry.

The present global leaders are Ocean Power Delivery (based in Leith) which has already secured significant export business for a Portugese wave project.