An Offshore Problem

Offshore sub station

Offshore and nearshore infrastructure is becoming increasingly important, is the UK defence, policing and security infrastructure too fragmented to adequately protect them?

Only a few weeks ago, during the unseasonal cold spell, we saw how a less than 8 hour disruption to the Interconnector natural gas pipeline between the UK at Bacton and Belgium at Zeebrugge caused serious price fluctuation as the UK waited for a couple of LNG tankers to arrive at the Isle of Grain and Milford Haven.

The problems at the Interconnector were caused by a failure of a connection to a pump on the hot water system and a resultant shutdown. Other capacity reductions have been caused by planned preventative maintenance.

What the problem highlighted is the potential vulnerability of the UK to disruption caused at a small number of geographic locations.  Milford Haven has a couple of very large LNG terminals and the economics of operating LNG regasification infrastructure drives geographic concentration, hence concentration of risk.

Although the plans themselves are ‘huge’ and therefore have some considerable resistance to damage the jetty facilities are less so

"Mozah”, the world’s largest LNG vessel, arrived on its maiden visit to the South Hook LNG Terminal in Milford Haven, Wales, heralding a new era in the history of liquefied natural gas (LNG) transportation.
“Mozah”, the world’s largest LNG vessel, arrived on its maiden visit to the South Hook LNG Terminal in Milford Haven, Wales, heralding a new era in the history of liquefied natural gas (LNG) transportation.

It is not the plant that would be targeted, it is the jetty.

Conventional oil and gas pipelines are robust, well buried and very secure.

As the UK increases its reliance on offshore wind power their protection is also subject to consideration. As with LNG regasification plants, the economics and physics of offshore wind mean that they have to be clustered.

Offshore Wind Farm
Offshore Wind Farm
Offshore Wind Farm
Offshore Wind Farm

By virtue of their separation, these clusters are highly resilient. Each wind turbine is very tough and it would take some considerable effort to create a significant disruption.

However, distance, power efficiency and maintainability concerns mean that AC and DC substations are often placed above water, on platforms such as those shown below.

Offshore wind farm power components
Offshore wind farm power components
Offshore sub station
Offshore sub station
Offshore wind farm power cable schematic
Offshore wind farm power cable schematic

The huge 1GW London Array that will provide over half of the Government’s 15% renewable target by 2015 has two such sub stations, provided by Siemens, each containing a 180MVA transformer and associated switchgear that aggregates the power from the turbines and steps it up from 33kV to 150kV before transmission to land.

Siemens Offshore Sub Station
Siemens Offshore Sub Station

All cables are buried and the four export cables terminate at Cleve Hill sub-station and connect to the National Grid from there.

Offshore power cable
Offshore power cable

The export cables from Nexans/JDR are of an interesting design, combining both power and fibre optics for control and telemetry. The image below is not from the London Array but is of a similar construction.

Offshore wind farm power cable
Offshore wind farm power cable

Buried cables and duplication from the four export cables provide a high degree of resilience to damage from fishing vessels.

However, the cables are typically buried between 0.5m and 3m deep and the two sub stations are obvious points of failure.

Despite this cable diversity they all land at a similar location and terminate at a single onshore sub station.

Given the size of some of the wind farms, should planning conditions include onshore diversity?

The UK is well blessed with undersea telecommunications cable diversity, as one would imagine.

TeleGeography produce an excellent map of submarine telecommunications cables, click here to view and an interactive version here

Submarine Cable Map
Submarine Cable Map
Submarine Cable Map
Submarine Cable Map

Submarine cables do sometimes get damaged from fishing vessels and a recent incident in Egypt demonstrates how they can be vulnerable to malicious damage.

The SMW4 maritime cable was cut at 8 am around 750 meters north of Alexandria, which slowed internet service in Egypt and other countries.

But industry officials said they were hard at work to get services up and running.

“[Internet services] will be back 100 percent on Thursday morning,” he said. “We are using alternative feeds.”

Finally, as the offshore hydrocarbon industry moves increasingly towards underwater compression infrastructure the traditional oil and gas platform may become a thing of the past.

Shell are currently trialling a subsea compressor in their Ormen Lange gas field off Norway. This facility requires power from the shore, another subsea cable requirement. Perhaps future production facilities around the Falkland Islands will not look like what we expect at all.

There is an increasing financial and strategic reliance on ‘offshore’ infrastructure; be that gas, telecommunications, hydrocarbons or power and the deployed infrastructure has multiple risk concentration points.

The UK offshore environment is a very complex subject, informed by a number of national and international laws and conventions. Broadly speaking it is divided into 4 areas, internal waters, territorial sea, EEZ and continental shelf.

Other states have many rights within this area such as innocent passage and in some regards the UK has relatively little legislative jurisdiction, fishing for example. A number of international conventions also complicate matters, the OSPAR Convention on waste dumping for example.


Devolution of power to Northern Ireland, Scotland and Wales also contribute to the patchwork of legislation that governs the UK EEZ.

British Overseas Territories and Crown Dependencies that are not part of the EU, such as the South Atlantic, also have EEZ’s. Combined, the UK has an enormous EEZ, the fifth largest in the world at over 6.8 million square kilometres.

UK Territorial Waters
UK Territorial Waters

Unlike some military capabilities there is a veritable menagerie of interested parties, the MoD, Maritime and Coastguard Agency, DEFRA, devolved administrations, EU, various police services and agencies, security services and the UK Border Agency amongst others.

Also to be taken into consideration is the UK’s increasing cooperation with France, India, Brazil, the USA and Japan, whilst not direct stakeholders they all have a direct or indirect interest.

The UK has recently established a single National Maritime Information Centre at Northwood as a single point of contact and information fusion, analysis and dissemination but without a range of assets it is difficult to see its potential maximised.

Maritime security is managed by the Maritime Security Oversight Group

The 2010 SDSR recognised that no single body could or should be responsible for maritime security so the establishment of NMIC was a good move, at least it would provide some measure of coordination.

There is still duplication though with overlapping surface and aircraft provision across the numerous interested parties.

As resources continue to be pressed, low profile but vital functions such as MSOG and NMIC are likely to be starved of funding undoing much of their good work and ensuring they fail to achieve their potential.

The cancellation of Nimrod has also seriously impacted on this requirement.

Does the UK, with its diverse range of interested parties, have a sufficient handle on the security implications of this increasingly critical offshore infrastructure?

Are the cross departmental structures and working arrangements in place but no resources to do anything?

What can the UK learn from the USA, Canada, Australia or Norway for example?

Does our regulatory and departmental diversity work against us?

Where does the Royal Navy and Royal Air Force fit in, would alternatives pull funding from defence?

These are complex and difficult issues but is it time for a cross departmental, single ‘Coastguard’ style organisation to be established, one that can adequately address a mission set as diverse as rescuing errant day trippers, protecting offshore infrastructure from terrorists and dealing with pollution from underwater compressors off the Falkland Islands whilst fending off Spanish incursions in the waters of Gibraltar?

Or is that the problem right there?

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