June 22: Preparing the Big Floater
AWS Ocean Energy in Alness, Scotland, is developing a giant floating device that is to bop with large ocean waves and to convert the movement into electricity. They don't want to be the first commercialising marine energy, but they do want to be the best.
The prototype that looks like a giant upturned table was built in Romania in 2001. The 4,000 tonnes steel device was then towed to Portugal, where it was prepared for the tests. In 2004 it was sunk to the bottom of the Atlantic Ocean and connected to the grid. Lo and behold, it worked. And for about three weeks, it delivered power to the grid.
In the middle of the 'upturned table' sits a giant cilinder that is partly filled with air. As waves pass overhead, the local pressure changes, making the submerged cilinder swim up and down with the passing waves. Inside the cilinder, a line of permanent magnets move vertically in front of a row of coils, inducing electrical current in this so-called linear generator.

Model of the prototype

The idea for a floating or swimming device bopping with the waves originates from the Dutch inventor Fred Garner who called his device the Archimedes Wave Swing, AWS for short. It was an Eureka moment for him, muses Graham Bibby, Operations Director at AWS Ocean Energy.
Now AWS Ocean Energy is preparing a next prototype to be tested at the European Centre of Marine Energy at Stromness 'sometime in the next years', says Bibby. ”In the next couple of years we're planning 'to get wet again'. We need to get this right. Because the cost of getting it wrong at big scale is almost damaging to the point of death to an individual company.”
Bibby is a bit fed up with the list of 'firsts' in this line of industry: “If somebody gets it right tomorrow, we'll take our hats off for them and say okay, well done. But that's unlikely. What's more likely is that there's an opportunity to get a better solution, a more cost-effective solution, a safer solution, or an easier to maintain solution, or a solution which impacts less on the seabed.”
So, they take their time at AWS, housed on the first floor of a non-descript building on an industrial estate in Alness. A team of seventeen people are working 'to get it right'. They have attracted investors like Shell Technology Ventures Fund and Kender Capital bv, both from The Hague, Netherlands.

Graham Bibby and Ben Yeats

When asked if they are not under pressure of investors to proceed faster, Bibby replies: “The pressure is to be right. Our investors ask for the progress we made, what we have learned and how can that improve things for you. They are asking us how we are going to adjust our plans”. Ben Yeats, Head of Marine Operarions, adds: “The investors need to be in tune with the developmental nature of the project. They need to be aware that there is a lot of learning going on and the difficult part is getting the economics right.”
AWS is confident that a market for wave- and tidal energy is emerging. “The waves will still be there on the long term, global warming will still be there because the energy demand is still expanding”, says Bibby. Besides there are the EU energy targets for 20 percent renewable energy by 2020 driving the market for renewables.
Another sign of growing interest in marine energy is the current 'gold rush' for access to the currents of the Pentland Firth between Scotland and Orkney. Yeats: “There is a landgrap going on by developers and utilities acquiring sites. The ground estates have the right to the seabed. There's a licensing going around similar to offshore wind. The majority will be tidal developers, but there will be wave developers as well.”
They expect wave and tidal energy to follow in the wake of offshore wind energy. Bibby: “At the moment the ocus is on offshore wind, up to 2020. We will be developing small farms in the meantime. Government target is 1-3 gigawatts in 2020, but the real target is 20 gigawatts in 2025. All major deployments in marine energy will take place between 2015 and 2025.” Yeats adds that developers aim at 100 megawatt wave and tidal 'farms'.
Dimensions of the device under development are not given. The prototype was aimed at an electrical power of 2 megawatts. After re-evaluation, the AWS team tends towards a larger rather than a smaller device because of the economies of scale.
Last year, the Scottish goverment put a new beacon on the horizon for marine energy developers. The so-called Saltire Prize promises 10 million pounds for the first wave or tidal energy device that generates 100 gigawatthour ocean energy. A single 2 megawatt would need six years of continuous production to reach that amount. But a farm of ten devices could win the prize in little over half a year.