By Christine McGourty
Science correspondent, BBC News
A new wave energy device known as "Anaconda
" is the latest idea to harness the power of the seas.
Its inventors claim the key to its success lies in its simplicity: Anaconda is little more than a length of rubber tubing filled with water.
Waves in the water create bulges along the tubing that travel along its length gathering energy.
At the end of the tube, the surge of energy drives a turbine and generates electricity.
The device is being developed by Checkmate Seaenergy Ltd,
which has been testing a small-scale 8m-long prototype in a wave tank in Gosport, Hampshire, owned by the science and technology company Qinetiq.
Paul Auston, chairman of Checkmate
, says the tests have proved the concept works.
The company is now looking to raise £7m from investors to build a larger version to test at sea.
"We've seen excellent results in scale-model testing, and now we are gearing up to attract the necessary investment to develop Anaconda and begin producing the first full-sized units for ocean testing within the next three years," he told BBC News.
"The UK is known for its engineering excellence and politicians from all parties have been keen to challenge companies to come up with renewable energy projects that can be sold around the world.
"With Anaconda, we have an invention that changes conventional thinking and it can help to meet government targets for cutting CO2 by providing renewable wave energy from our coastal waters.
"It will also help cement the UK's world-leading position in this technology."
The co-inventor of the device, Professor Rod Rainey
of engineering design consultants Atkins
, has been working in the field for several decades.
He said: "The beauty of wave energy is its consistency. However, the problem holding back wave energy machines is that devices tend to deteriorate over time in the harsh marine environment.
"Anaconda is non-mechanical. It is mainly rubber, a natural material with a natural resilience, and so has very few moving parts to maintain."
The long-term plan is to have hundreds of these devices offshore where waves are big, in northern Scotland for example.
Other potential locations would be on western seaboards - off the coast of America, Australia, Ireland and Japan, to name a few.
It is claimed that a group of 50 full-size Anacondas - each 200m long - could provide electricity for 50,000 homes.
Professor Godfrey Boyle
, an expert in renewable energy at the Open University, said the device sounded quite promising.
If the required investment capital can be raised, the team "could be on to a winner", he said.
But he cautioned that the developers would need to achieve very long lifetimes for the device and the very high reliability required to withstand decades of battering by the waves - combined with low capital and maintenance costs and high-energy conversion efficiency.
Waving or drowning - is an Anaconda the answer?
By Richard Cable
In renewable energy terms - that is, non-carbon producing power generation - wave power would appear to be a much better source of potential energy than wind power.
Primarily, this is because waves, while produced by the wind, tend to be much more consistent than the wind.
(When was the last time you went to the beach and thought: 'There really are no waves at all?')
So why the heavy focus on legions of white Wind Martians marching across our spotless countryside?
Well, because wave power is much more difficult to harness.
It's slow and irregular, therefore difficult to convert into electricity, and it's ferocious.
Salt water and high seas can dispense with a fancy man-made turbine quicker than a pressure group can be formed to complain about how ghastly it looks floating around off our spotless coastline.
But a prototype built by a small British company may have taken the first steps towards a truly workable solution (with apologies to existing wave energy capture projects like Portugal's Aguçadoura Wave Park.)
Checkmate Seaenergy's 'Anaconda' is potentially game-changing because, it has 'so has very few moving parts to maintain'. Unlike other solutions, it provides a radical answer to the business of being persistently battered by waves: there's hardly anything to break.
It's basically a big rubber tube full of water that waves 'squeeze' as they travel past.
The resulting bulges are forced, by the wave, along the tube, gathering energy which is ultimately converted into electricity by a turbine at the end.
The simplicity is beguiling, but at the moment the prototype is only eight feet long and has only been tested in a lab.
The full-scale version will cost several million to build and will be subjected to the true fury of nature.
Even if it does work in the real world, it's projected that around 50 Anacondas, each 200 metres long, would be required to power 50,000 (presumably coastal) homes.
Not great stats, but interesting and the technology could well improve.
One to watch.
The 'Anaconda' explained on the New Scientist YouTube channel
The Anaconda Wave Energy Converter
Anaconda uses an entirely novel concept to harvest wave energy.
Wave energy is free and widely available to the UK and Eire.
Other potentially rich coasts include the USA and South American western seaboards, South Africa, Australia, parts of Malaysia, Japan, New Zealand and the western facing coasts of Europe.
The Inventors proposed the concept of a distensible rubber tube anchored to the seabed and floating just beneath the surface head to sea, in which bulge waves are excited by passing sea waves.
The device is continually squeezed by passing sea waves.
These waves form bulges in the water-filled tube and travel down its length developing the power to drive a turbine generator in the stern.
Wave energy is a particularly rich, but as yet untapped, energy resource which government studies state could produce 3%-5% of our electricity initially and up to 20% eventually.
The Anaconda project team has been testing a scaled device, part of a programme of rigorous development, completing the final stage of an exhaustive proof of concept phase at QinetiQ’s Haslar Marine Technology Park at Gosport, Hampshire using the UK’s largest wave testing facility where the strength and frequency of ocean waves the device may encounter can be simulated.
Paul Auston, Chairman of the Checkmate Group
, said: “The UK is known for its engineering excellence and politicians of all parties have been keen to challenge companies to come up with renewable energy projects that can be sold around the world. With Anaconda we have an invention that changes conventional thinking and it will help to meet the ambitious government target of providing renewable wave energy from our coastal waters. It will also help cement the UK’s world leading position in this technology.”
“We’ve seen excellent results in scale model testing, and we are now gearing up to attract the necessary investment to develop Anaconda and take this proven concept through to full commercialisation within the next five years.”
The interaction of the bulge tube with the surrounding sea waves is complex and has become the subject of an Engineering and Physical Sciences Research Council grant funded study led by Professor John Chaplin. The study will result in a detailed numerical model of the bulge tube and will help us to optimise tube efficiency in real sea conditions.
Bulge Tube Operation…
As the bulge waves travel down the tube and arrive at the stern, the pressure in the chamber ahead of the power-take-off cycles above and below the tube’s rest pressure.
During the high pressure part of the cycle, water passes through a set of non-return valves into an accumulator where pressure is allowed to build up. A smoothed flow of water then passes from the accumulator into a conventional hydraulic turbine which drives an electrical generator.
On exit from the turbine, the water is accepted into a low pressure accumulator and is then drawn through another set of non-return valves back into the main tube during the low pressure part of the bulge wave cycle.
Cost Of Energy...
Independent analysis of Anaconda by the Carbon Trust suggests ‘it has the potential to deliver breakthrough reductions in the cost of wave energy’ and that ‘it could represent the next generation of marine renewable energy’.
Based on a study from the Carbon Trust Marine Energy Accelerator the projected costs of Anaconda could represent a step change for the industry and a significant improvement over the best current marine renewable energy devices.
Because of its novel concept and unique method of gathering sea energy from long ocean swells, Anaconda has a number of features which mean it has the potential to be very cost effective.
No new technology has ever been without challenges to its introduction.
Anaconda breaks new ground in many ways, but it does not demand new science or materials. Nevertheless, it will be the largest rubber fabrication ever made.
With all renewable energy projects there is a political dimension surrounding development and particularly the will to accept and invest in large scale installations.
Anaconda, by virtue of its cost effectiveness and low environmental impact, has the potential to transcend these issues thus ensuring its success.
Professor Rod Rainey, of design engineering consultants Atkins, one of the co-inventors said: “The beauty of wave energy is its consistency. However, the problem holding back wave energy machines is that devices tend to deteriorate over time in the harsh marine environment. Anaconda is non mechanical: it is mainly rubber, a natural material with a natural resilience and so very few moving parts to maintain.”
Anaconda uses an entirely new way of harvesting wave energy.
• Wave energy occurs due to movements of water near the surface of the sea. Waves are formed by winds blowing over the water surface, which make the water particles adopt circular motions. This motion carries kinetic energy, the amount of which is determined by the speed and duration of the wind, the length of sea it blows over, the water depth, sea bed conditions and also interactions with the tides.
• Waves only occur in the volume of water closest to the water surface, whereas in tides, the entire water body moves from the surface to the sea bed
• In Tides, the energy is due to a net movement of water, but in Waves, the water acts as a carrier for energy, moving it in some directions but it does not undergo a net movement itself.
• Waves are formed by the wind – the stronger the wind and the longer the distance over which it blows, the larger the waves and the more energy they carry. For that reason waves on the West Coast of the UK tend to contain more energy than the East Coast.
Essentially, it is a very large water filled distensible rubber tube floating just beneath the sea surface at right angles to the waves, with a power take off at the stern.
As a wave passes the bulge tube is lifted with the surrounding .water and causes a bulge wave to be excited which passes down the tube’s diameter like a pulse in an artery, gathering energy from the sea wave as it goes.
Continuous energy gathering results from resonance between the bulge wave and the sea wave. Energy from the sea wave is stored in the rubber as it stretches.
The bulge wave travels just in front of the wave rather like a surfer, picking up energy as it increases progressively in size. At the end of the tube the bulge wave energy surge drives a turbine in the power take off after the flow has been smoothed.
The Anaconda Team
Paul Auston, Chairman
. He started Checkmate’s manufacturing business’s of which he is also Chairman. He has over 27 years of Industrial and Commercial experience
Des Crampton BSc (Eng), Chief Executive
, Checkmate Seaenergy. Des started his career as a mechanical engineer in the steel making industry before taking up the challenges of the UK ports industry, most recently as Managing Director of Medway Ports and a director of Mersey Docks and Harbour Company and Peel Ports. His technical and commercial skills are of particular benefit to the company. Des is a lifelong offshore sailor who last year single handed in his own yacht in a race from UK to the Azores .
Mark Prentice BSc, MIME, C Eng.
Technical Manager of Checkmate Flexible Engineering LLP, Seconded to Checkmate Seaenergy he brings to the Anaconda project his unrivalled knowledge of rubber fabrication and flexible structures as well as his experience of mechanical and structural design.
Steve Rimmer BSc.
Project Manager. He trained as a chemist and has worked in technical and managerial roles in the rubber industry for over 30 years. Steve has extensive knowledge of rubber compounds being responsible for rubber compound characterisation, optimisation and testing. As well as having extensive knowledge of materials, Steve is also experienced in rubber manufacturing and fabrication.
Ushpal Thind BEng
. Project Engineer. Ushpal joined Checkmate some years after graduating in engineering from Imperial College London. Seconded to the project, he works on all aspects of the design, manufacture and testing of our products. He contributes to all aspects of the Anaconda project, most notably to model design and testing.
Professor Rod Rainey, MA MSc DIC CEng FIMarEST
. Co-Inventor of Anaconda. He is Head of Floating Structures at WS Atkins plc Oil and Gas Division. Rod is one of the UK’s leading experts on floating offshore structures, and has a unique combination of practical and theoretical know-how in this field. He has been employed by WS Atkins for over thirty years. Prior to this he was employed by Yarrow Shipbuilders and was a research fellow at Imperial College. He is an international recognised authority in the field of Hydrodynamic loading, and hosted the International Workshop on Water Waves and Floating Bodies, at Peterhouse, Cambridge. He has published extensively in the international technical literature. He is a visiting professor at University College London and at Southampton University.
Professor Francis Farley, ScD, F Inst P, FRS
. Co-Inventor of Anaconda. He is an experimental physicist with wide experience of making things work: wartime microwave radar which controlled the Dover guns, innovative experiments in particle physics at CERN and Brookhaven and new wave energy devices. He is a fellow of the Royal Society which awarded him the Hughes medal. Francis has worked on wave energy since 1976 and has filed 14 patents in this area.
Checkmate Seaenergy Limited
Unit 6, Pegasus Way
Telephone (head office) +44 (0) 1795 580 333
Fax (head office) +44 (0) 1795 668 280