Select Committee on Science and Technology Minutes of Evidence

Memorandum submitted by Dr Alan Wells in collaboration with David Langston of Wavegen


  1.  Wavegen is a private sector company that has undertaken research, development and commercialisation of various forms of wave energy over the last 10 years, in close collaboration with academia.

  2.  Wavegen owns and operates a 500kW wave energy converter off the west coast of Scotland and has built 3MW of plant to date.

  3.  Wavegen is a company dedicated to the extraction of energy from waves, and will not be commenting on tidal energy.


  4.  Whilst efficiency, the conversion of the energy available in the wave front into electrical power, is a useful measure the key factor to consider is the cost of the power produced, that is p/kWh. So a relatively inefficient device with a low capital cost could be a better technical solution than a very efficient device but with a correspondingly high capital cost.

  5.  Wavegen has built a Limpet 0.5MW device on the island of Islay, off the west coast of Scotland. This plant follows the earlier 75kW pilot plant built by Queen's University of Belfast. The plant is currently supplying power to the national grid. The plant has recently moved from manned operation only to remote control with 24 hours per day operation.

  6.  Building the Limpet plant and monitoring its operation has provided valuable data, which will be used to improve the performance of the next generation of Limpet device. Redesign proposals already exist for substantial cost reductions with greater site flexibility.


  7.  Wave energy will become commercially viable for the supply of electricity for the grid. The first UK wind projects (NFFO-1) produced electricity more expensively than the current Limpet wave plant. Since the early NFFO projects the cost of power from UK wind farms has dropped by a factor of approximately six. Provided that the development of wave energy is adequately supported in the near term then it will follow the same trend.

  8.  The energy market is full of existing technology that has received and is still receiving direct or indirect national subsidies. Wave power has the potential of being a substantial industry and yet it is not yet receiving sustained and coherent support necessary to move from research to commercial demonstration. Wave energy is commercially competitive niche markets, such as remote islands and oil and gas subsea developments.


  Development over the past 25 years of wave power plants has been slow in the UK, and indeed elsewhere, for cogent reasons. Although the annual offshore potential power output is substantial, there are also extreme storm conditions to be faced, with temporary power fluxes sometimes larger than the mean by an order of magnitude, but without any well defined upper limit. This introduces design uncertainties.

  The potential profitability of wave power is also limited, as for instance compared with the winning of hydrocarbons offshore. This may be illustrated by comparing added values from compression of seawater on the one hand to drive hydroelectric plant, and on the other hand to be used directly for displacement by dosed injection at declining hydrocarbon well systems, where the value of additional hydrocarbon products, even when heavily discounted by seawater leakage losses, will be at least an order of magnitude greater. It arises from this, firstly that oil-related offshore technology is often too expensive to apply to wave power extraction plants; this has encouraged the trial of unconservative prototype plants. But secondly, a historical comparison with the progression of commercial square rigged steel sailing barques late in the 19th century, compatible with the most adverse storm conditions, shows that economic solutions could also be found for wave energy plants. The lessons so far from these experiences have been mainly (1) that wave power conversion plants should be minimally attended and (2) that the technology to be employed should be as simple and rugged as possible, requiring the minimum maintenance. These lessons will be learned, and wave power will become one of the significant sources of renewable power, probably commencing in niche markets. Suitable candidates are (1) oceanic islands, (2) seabed hydrocarbon wellhead systems, with or without dosed seawater injection and (3) clean pressurised seawater desalination, by membrane or vacuum/compression/condensation/distillation (VCCD) systems.

  Despite long development lead times, one considerable advantage of wave power conversion systems in general is that their construction lead times are short, which can have a favourable effect on reducing capital costs. Serious attention might also be given to synergistic applications. Thus, a cable ring main laid on the seabed to serve pumping installations for a group of offshore oilfields, initially using electric power from ashore might towards the end of oilfield life have wave power plants connected to it, so as to deliver power ashore with storage, particularly for use with electric vehicles, or gasification and synthesis of municipal waste with oxygen to form diesel fuels. Now is the time for serious study of these possibilities.

  9.  The time required for wave energy to become a commercially competitive source of power is largely dependent upon how much positive encouragement its development is given in the near term. If resources are committed quickly then the technology will mature more quickly determined only by the availability of adequate inventive and intellectual talent. Whereas, if the same amount resource is eked out slowly there is a probability that the technology will not mature in the UK but become an imported technology.

  10.  Two of Europe's largest venture capital funds and its third largest oil company have already invested in Wavegen. These investors have been attracted by the prospect of a profitable global industry evolving.


  11.  The Limpet 500 plant is successfully operating on the island of Islay. It is a 0.5MW oscillating water column with a Wells turbine power take-off. The project which was part financed by the EU secured an SRO-3 (Scottish Renewable Obligation) contract for the sale of the power.

  12.  The Limpet 500 follows on from the successful DTI funded 75kW plant, also on Islay, built by Queen's University, Belfast in 1990. As part of the DTI contract this plant was decommissioned in early 1999.

  13.  The Limpet 500 is currently constrained to a maximum power output of 150kW due lack of capacity in the local grid. Shortly after commissioning was complete in November 2000 the plant exported power at maximum capacity. At the end of January 2001 we moved to remote operation—24 hours per day.

  14.  The plant has been built to enable data to be collected for further R&D leading to improved performance from future devices.

  15.  The Osprey I near shore 2MW project of 1995 using reversible pneumatic turbines, was undertaken by Applied Research & Technology. The welded steel structure was built in the Clyde, towed 450 miles to Dounreay and successfully settled on the seabed after receipt of a satisfactory weather window forecast from the Met Office. A 2m swell from the North arrived soon after placement and persisted for a week. The work boat could pump neither ballast sand nor cement grout, nor place anti scour mats, although the divers did obtain videos underwater. These showed that the seabed wave motion eroded sand around the bilges and the unballasted structure buckled and broke its back on the remaining humps. After the swell had subsided the decision was taken and implemented to retrieve the turbo generators. The loss report was accepted without reservation by the insurers, on the basis of "perils of the sea". They compensated in full but removal of the wreck required by the Crown Commission, required the sourcing of a large Dutch jack up crane barge and this operation cost more than the Osprey prototype. Costs were also inflated by the discovery of irradiated metal particles on the structure from seabed contamination. The associated procedures and diving equipment needed for handling this contamination risk more than doubled the budget. The project provided valuable lessons for the development of future marine renewable energy projects.


  16.  Wave power should be recognised as being able to make a significant contribution to the renewable target by 2010. The UK has the technical lead. It also has the skills and resources from the declining offshore Oil & Gas market. If this opportunity is not grasped now then others will pick up the opportunity and in a few years the UK will be importing Wave Energy Converters from the new market leader. The wave industry in the UK has the potential to become a major industry worth billions of pounds. A strong home market is essential in developing this opportunity. This can only be achieved by it having a high priority in the Government's renewable energy strategy. This is not the case at present.

  17.  The Renewables Obligation—Preliminary Consultation document issued by the DTI at the end of 2000 contained information regarding a proposal for Capital Grants for Offshore Wind projects "to stimulate early deployment of a significant capacity of offshore wind farms". The UK has an excellent wave climate, it is at the forefront of the development of wave energy technology and yet Capital Grants are to be made available for imported wind energy technology. The Renewables Obligation timetable indicates an end date of 31 March 2026 but without mentioning the option of future Capital Grants being made available for wave energy. A more positive statement toward wave energy would have given the encouragement that the capital markets needs to co invest.

  18.  With the wind industry the Danish Government has successfully demonstrated how a strategy of supporting the development of renewable energy technology at home can result in a new industry with significant exports. It now employs more people that the UK's coal mining industry.

  19.  With world demand in energy increasing at about 2 per cent per year, oil controlled by a small number of politically influential countries, nuclear power stations coming to the end of their lives and short-term local gas supplies, also with a vast untapped global wave resource and the necessary skills and resources becoming available from a declining offshore oil and gas industry, it makes sense for the Government to encourage wave energy. In addition to achieving substantial domestic renewable power production it will also create a valuable export market for manufactured goods.


  21.  In March 1999, the Government launched a new wave power programme to monitor the development of the SRO-3 schemes and fund research, development and demonstration projects. £1 million of R&D funding has been contracted mostly for collaborative device development projects. The DTI's New and Renewable Energy Programme budget of £14 million in 2000-01 covers a wide range of activities. The actual amount that is used to assist in the development to wave power devices is small.

  22.  Wavegen is receiving funding from the DTI for the development of a floating attenuator device.

  23.  It is not clear how national funding for R&D is being co-ordinated or what sort of peer-review processes are undertaken.


  24.  A number of national and international official studies have confirmed that there is minimal impact from wave energy devices.

  25.  Offshore wave energy devices carry almost no negative environmental impact, apart from the usual construction and decommissioning impacts for those living near fabrication sites. They are placed in deep water and can also be sited close to oil installations where their function would be to assist in the development of marginal fields or to extract difficult-to-recover reserves from existing fields. They provide a clear environmental advantage over current mechanisms for generating electricity offshore.

  26.  Of all the renewable energy forms, it appears to us that wave provides the lowest level of negative environmental impact coupled with the highest level of positive environmental impact. It is the only form of energy generation we are aware of which may, in fact, be deployed as much for its positive environmental effects such as protection against coastal erosion or provision of potable water as for its ability to generate electricity.

  27.  In developing nearshore or offshore wave energy projects it is necessary to account for the physical obstacle that they represent to other sea users, including fishermen, shipping, navigation, Ministry of Defence (MoD) practice exercises and anchorage areas. In general, sites that are good for wave energy are not in high demand by other users.

  28.  Detailed consultation during the scoping phase of a wave energy development should rule out locating wave energy devices in particularly busy marine areas so reducing the risk of obstructing other sea users. Admiralty charts, traffic surveys and liaison with key personnel such as harbour masters, coastguards and the MoD will identify shipping routes and other sensitive users.


  29.  There is a growing number of countries that are showing significant interest in wave energy and so Britain runs the risk of falling behind. In addition, the country that demonstrates commitment is the country that wins the prize of a future major industry. The UK is well placed with its wave power technology and skills and resources from the Offshore Oil & Gas industry. It is more than likely that one country will dominate the market. This is the case for Denmark in the wind industry. If the UK does not capitalise on its present opportunity regarding wave power then in 10 years' time it could be importing wave energy devices from a country that was handed a golden opportunity.

  30.  A number of projects have been undertaken abroad, for example the IPS Buoy in Sweden, Mighty Whale in Japan, OWC with Wells Turbine (supplied by Wavegen) in the Azores, an OWC in Norway. To date these projects have not been resoundingly successful, but they have added to the body of knowledge. More and more countries are developing wave energy technology. There are Australian, US, Dutch and probably other developments that are nearing finalisation, which could erode the UK's lead. Some of these are described in the book "Power of the waves" by David Ross, OUP, 1995, ISBN 0198565119.

10 February 2001

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