These pages are largely made
up of un-published information from the Edinburgh Wave Power Group which
is now incorporated in the Institute
for Energy Systems of the School of Engineering at the University
of Edinburgh. During the 1970s and 1980s we also referred to ourselves
as the 'Edinburgh Wave Power Project'.
Power Group at the University of Edinburgh dates back to 1974 -
the year that Stephen Salter invented the 'Duck' as a means of converting
into electricity some of the abundant natural power that arrives
as ocean waves on our western shores.
The first duck. Stephen Salter on right with David Jeffrey the co-founder
of the Wave Energy group.
of Duck full-scale engineering design
is a crest-spanning, spine-mounted, slack-moored, deep-water,
floating, electricity-generating, terminator. Tank tests showed
that it could capture energy from regular waves with great efficiency.
Development of 'smart' dynamometers using force-based transducers
with analogue electronics showed how to get more and more power
out of mixed and ever-changing sea-states. The final goal was
to get near to the utopia of real-time 'complex-conjugate' control.
The engineering challenge was how to build
these ideas into a system that would convert the raw sea power
into electric current suitable for grid connection and survive
at sea. As the 'power-take-off' designs evolved, they gave birth
to a new generation of high-pressure oil-hydraulics that now finds
much wider application.
first sketch, as published in Nature.
single ring-cam & twelve-ram active joints
Robert Clerk surrounded by the designs for his 'trilink' machine.
of the duck concept so that it might compete economically with conventional
sources of energy required several new technologies. Above all, there
was a need for very high efficiency high-pressure bi-directional oil
hydraulic transmissions that could implement the advanced control
algorithms required to get the most energy out of waves. With the
arrival of Robert Clerk and
his ground-breaking designs, we started in the early 1980s to develop
a new generation of high performance hydraulic machines. Building
on that experience, a new company called Artemis
Intelligent Power Ltd. was founded in 1994 by Win Rampen and Stephen
Salter to develop the next generation of hydraulic machine. They call
this new technology 'digital hydraulics'.
From the beginning,
wave energy research needed a new generation of high-fidelity test tanks,
and concurrently with the invention of his Duck Stephen Salter created
the first 'absorbing' wavemaker. This became the foundation of our accurate
and highly repeatable narrow tank work and led in late 1977 to the revolutionary
Wide Tank. In 2001 we had to dismantle
the Wide Tank, as the site was required for a long-delayed building project.
We replaced it with the novel and user-friendly Curved
Tank. It was built by our spun-out colleagues at Edinburgh
Designs Ltd, the world leaders in wave-making and test-tank design.
Control bench for the old narrow tank. Real time multi-axis analogue
control - the best thing for optimising a wave energy device.
Chris Retzler and Andy Knox flying the spine model in the wide tank.
Computers had taken over.
Duck model on the surging heaving rig meets 50 year wave. As good
as it gets in a narrow tank.
First 'sneak' wave in the Curved Tank - the most intimate of multi-directional