SUB-SEA TIDAL STREAM SOLUTION LEAVES WAVES IN ITS WAKE

The first significant UK wave-power electricity may be as late as 2030 before it is generated on any scale. There is a plethora of designs, none of which have so far proven economically viable, with several high-profile financial failures in the mid-2010s.

By the mid-2000s Edinburgh University’s engineering department’s Professor Ian Bryden — who died suddenly in late 2016 — was active in analysing and promoting tidal stream electricity with academic colleagues throughout the UK as the way forward.

“The Inner Sound is correctly seen as an important world-scale tidal-stream green electricity test-bed.”

Fast forward to 2007, the year that Atlantis RL picked the Pentland Firth’s Inner Sound as its first choice of UK tidal-stream electricity development sites.

The Sound is the 1.5 miles wide “secondary strait” between the Scottish mainland and the mid-firth isle of Stroma, appropriately named over 1,000 years ago by the Vikings as “the island in the stream” (literally strom oy; “stream island”).

Atlantis RL’s consortium was one of 14 bidders for the Crown Estate lease of an area of seabed under waters between Gills Bay and Stroma, both in Caithness, in the Northernmost part of Scotland’s Highland region.

This then-tiny Singapore-registered company was Initially a junior partner in the winning group that was allocated the 400 MW-capacity site by the UK’s Crown Estate in autumn 2010.

Since then, Atlantis RL’s directors have determinedly grown the company. They built up a controlling interest in the Inner Sound site, in stages, by mergers and take-overs and, from time-to-time, pulling in as partners other businesses and agencies with relevant technical and financial expertise.

In 2015, Atlantis RL won the managing interest in the adjoining Ness of Duncansby 100 MW lease, off John O’Groats, in a deal with Scottish Power Renewables, of Glasgow, a subsidiary of Spain’s Iberdrola utility.

The company, which now has its HQ in Edinburgh in Scotland, was floated on the London AIM (junior) Stock Exchange in February, 2014. Its shares have been actively traded since.

Shareholders include major finance house “names”, notably New York’s giant investment bank 60,000- employee Morgan Stanley, with its world-wide motto: “We help build a sustainable future”.

Atlantis RL has gained the reputation of being nimble and rapidly honing the details of its operations to meet many separate sorts of challenges, whilst never taking its corporate eye off the ball about its eventual aims. Those are as providers of economically-attractive “green” sub-sea tidal power stations — and being creators of the very means to ensure that this occurs.

Creating the first phase of Atlantis RL’s Inner Sound sub-sea tidal-steam electricity location alone cost over £50 million, with significant contributions from UK public agencies.

An even larger sum has been spent — with substantial public-sector investment, particularly in the academic side — during the past decade into aspects of tidal stream electricity that have been essential in getting Phase 1A of the project to the “electricity-generation” juncture. This first 6 MW (capacity) step is due to be completed in mid 2017.

Now, in early 2017, Atlantis RL’s Phase 1B of its MeyGen site is well under way (with a further 6 MW capacity) and due for completion in 2018.

Tidal stream electricity makes use of novel 21st Century “horizontal hydro” technology, a culmination of many years of high-grade engineering, electrical and electronics research and development, largely in the UK.

Again, this high-tech work has received financial input from agencies of the UK and Scottish governments as well as the European Union, due to tidal stream’s importance as a long-term, non-polluting, “green” energy source, with a power output that can be readily reliably forecast.

“21st century technology in action under the Pentland Firth’s Inner Sound.”

Included is thorough seabed surveying with detailed measurements of the currents and examination of sub-sea turbulence at intervals in the 25/30-metre deep Inner Sound water-column. Also involved is designing, manufacturing, assembling, testing and emplacing the new-style lateral “hydro” turbines.

And that’s not to forget the very necessary “financial engineering” that has allowed this to be undertaken with Atlantis RL leading from the front, rather than following in the wake of others.

This latter encompasses the commercial know-how and agility that has allowed the four-turbine “demonstration” sub-sea site to be funded, including the “bulk” pre-selling of the electricity to be generated, with a bit of a helping hand from the UK’s taxpayers.

It further involved innovative, sometimes novel, concepts for seabed site selection/preparation for turbine deployment and installation, including having sub-sea support “jackets” fabricated and “machined” steel weights delivered for ballasting the turbine units to the 30-metre deep seabed.

Also needed were the manufacture of specialist — weighted and strongly insulated — 100mm (4”) diameter cables, laying those on the tide-swept (usually bare-rock) seabed and successfully jointing them.

Directional drilling down underneath the wave-swept Inner Sound’s rocky coastline and then up again to the seabed’s surface, created the boreholes to allow the heavily insulated “wires” to be hauled ashore to the purpose-built “power conversion building” (PCB) at the cables’ landfall on the Ness of Quoys, a low headland jutting out into Gills Bay.

The power from there is fed into the local electricity supply network.

In Phase 1A, each turbine had its own dedicated cable, but this will change to shared “wire”, as commercial tidal arrays develop.

The first stage is being immediately followed-up in 2017-18, with a four-turbine addition in Phase 1B, giving an early Inner Sound peak generating installation total of 12 MW.

Phase 1B, the “step” that will be operational in 2018, includes a European Union funding allocation of around £17.5 million, as the Inner Sound is correctly seen as an important world-scale tidal-stream “green” electricity “test-bed”.

Phase 1C is “the big one” commencing in 2019, states Atlantis RL. Costing over £420 million is for an extra 49 turbines that it claims will be on a scale enough to let manufacturing start at Global Energy’s Nigg yard — with the low-cost Gills Harbour Inner Basin workboat base expected to be in place by then.

Inner Sound MeyGen site is firm’s worldwide flagship

Alternatively dubbed “Project Stroma” or “Demotide”, the second stage of the MeyGen project, will see the supports of the generating nacelles being drilled and piled downwards into the sea-floor bedrock, some 30 metres below the sea-surface, Atlantis RL announced in early 2017.
This the alternative to the use of gravity “steel-weights”, as were installed in Phase 1A in autumn 2016, and seems to be a “preferred” longer-term solution for tidal turbine deployment in “fast-flow” currents.

AIM-listed Atlantis Resources Ltd, is now both active tidal-stream turbine developers under two separate “brands” (for use by its own generating arm, as well as sale to third parties), in addition to it becoming international tidal site utility generators (as in the Inner Sound).
It claims to have some 1,000 MW of tidal stream electricity under development world-wide, but refers to Inner Sound (MeyGen site) as its “flagship” pioneering project, attracting global attention.

As well as Ness of Duncansby, Atlantis RL has leases on several sub-sea tidal sites elsewhere in Scottish waters and off the coasts of England and Wales, as well as internationally, with an Asian emphasis.

The fact that “wave and tidal” is frequently lumped together as a single type of technology for official purposes (e.g. Crown Estate seabed lease sites) may have had a negative effect on tidal stream electricity — newspaper reports have frequently muddled the two. For tidal stream electricity is often confused in such genera) reports with so-far non-performing “wave energy converters”.

Meanwhile, the Scottish Government’s jobs agency, Highlands and Islands Enterprise, is active in a wave energy rescue effort from 2016 onwards. This is for a sector where finding fixed structures to stand up to extreme wave conditions has proved difficult to date and there have reportedly been some “large” storm-damage insurance claims. Floating wave devices (i.e. Pelamis Wavepower) have generated electricity in modest quantities, but not (so far) at a price that looks as if it can become competitive.

HIE’s Wave Energy Scotland is using patented technology from such as the Pelamis’s sectionally-articulated “giant steel cylindrical snak”’ floating device and is also “going back to first principles”, as the long-term goal appears very large, albeit somewhat distant, with, as yet, unproven technologies.