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GE Invests in OPD, Supplier of World’s First Offshore Wave Farm Project

The Pelamis Wave Energy Converter

GE’s Technology Lending is providing capital to Ocean Power Delivery, Ltd. (OPD), developer of the world’s first commercial facility that will generate electricity from offshore ocean waves. The transaction, made in conjunction with GE Energy Financial Services, extends a loan facility of $2.6 million (£1.5 million) to UK-based OPD.

Additionally, GE is taking an equity position as part of OPD’s $22.5 million (£13 million) equity financing as OPD prepares to deliver on its first commercial contract for a wave power farm.

OPD developed the Pelamis Wave Energy Converter, which generates 750 kW of electricity from offshore wave motion. In early 2005, OPD announced the signing of an order with a consortium, led by Enersis, to build the initial phase of the world’s first commercial wave-farm at a site 5km off the coast of northern Portugal.

The first stage consists of three 750kW Pelamis machines with a combined rating of 2.25MW. A letter of intent has also been issued to order a further 28 Pelamis machines before the end of 2006. When complete, the eventual 22.5MW project is expected to meet the average electricity demand of more than 15,000 Portuguese households while displacing more than 60,000 tonnes per year of carbon dioxide emissions from conventional generation using fossil fuels.

Pelamis Power Conversion Module

The Pelamis is a semi-submerged, articulated structure composed of four cylindrical sections linked by hinged joints, at each of which is placed a Power Conversion Module, each rated at 250 kW. The Pelamis, which is 120-meters long and 3.5-meters in diameter, swings head-on into incident waves.

Each of the three Power Conversion Modules resists the wave-induced motion of the joints with four hydraulic rams—two for heave (horizontal axis), two for sway (vertical axis). The rams pump high-pressure oil through hydraulic motors via smoothing accumulators.

Placement of the Power Conversion Modules

The hydraulic motors drive electrical generators to produce electricity. Power from all the joints is fed down a single umbilical cable to a junction on the sea bed. Several devices can be connected together and linked to shore through a single seabed cable.

The Pelamis uses a novel joint configuration to induce a tuneable, cross-coupled resonant response, which greatly increases power capture in small seas. Control of the restraint applied to the joints allows this resonant response to be “turned-up” in small seas where capture efficiency must be maximized or “turned-down” to limit loads and motions in survival conditions.

A proprietary mooring system comprising a combination of floats and weights which prevent the mooring cables becoming taut holds the machine in position. The mooring system maintains enough resistance to keep the Pelamis positioned but allows the machine to swing head on to oncoming waves.



Bjoern Sandvik

This is brilliant! I hope to see much funding for r&d into this technology in the very near future. For taking advantage of our potential abundance of renewable energy, this is undoubtedly among the top three sources, and it thrills me to see that it's ready to go live!



I read through some of the stuff on the company website, and one thing that they did mention was that since this is new, there will be economies of scale as they build more of them. It may well be true - I guess for now we just watch to see how things go with this first wave farm.

Harvey D.

How many of those 'energy transformers' or 'power conversion' are in actual operation?


anyone wonder why it is being done off the coast of portugal when some of the best water for this activity lies off our own shores?

1) Portugal is paying 28 cents/kWhr for alternative energy to spur developement.

2) The environmental permitting process for Portugal isn't a maze of confused red tape.

At a wave energy conference at OSU last year, the biggest barrier to developement was sighted as being the impossibility of obtaining environmental permits even to test something, because they can't prove the environmental impact without testing it.

So companies go overseas with green energy, while the domestic market flounders.


I'm a little sceptical of the reliablity of the mechanisms involved. All those moving parts subjected to continuous marine exposure. How many are in service now - for how long ? How much down time ? I remember wind turbines having reliablity problems in the 80's. Those problems were corrected after more realistic assumptions about the forces/enviroment exposure were factored into the newer turbine designs. I suspect the same thing will occur with this or similar devices. So first it has to prove itself in actual service, then any design deficiencies corrected, and then it will be more realistic to expect more and larger installations here in the US & elsewhere.

Dr S C Banerjee , MIEEM ,India

This WEC Pelamis , seems to be an excellent proposition awaiting practical trial in high wave power sites off-shore , at Portugal .I wonder whether it has a potential market with rather poorer wave power sites in Indian ocean or ,bay of Bengal in India and such sites .Nor is it known whether with sudden influx of high intensity storms or future aggravation of wave energy(in the eventuality of global warming)-it would be able to get tuned to take the advantage of high intensity waves- generating more power ,or shed the extra power availed or ,would cease to function ?
Clarificattion/Comments over these eventualities /market advancements are requested from the concerned R & D cell of Pelamis .
Dr S C Banerjee ,Consultant , Fir-E-Con ,India .

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