With apologies to Jules Verne – high voltage direct current (HVDC) cables convey rather more than 20,000 volts. According to Wikipediai most typically use voltages between 100 kV and 800 kV (although they are not limited to this range). Generally HVDC cables are used for wind farms some distance off shore (or to circumvent issues associated with overland transmission), but increasingly the UK’s wind generation is planned to come from islands, with a plan to “export” surplus electricity long distances. HVDC cables are seen as the means by which the electricity is to be transferred from the islands to the mainland.

As we saw in For Peat’s Sakeii and Utilities Futility,iii the Viking Energy wind farm on Shetland is one such development. The plan by SSE is to connect to the National Grid on the mainland via a new HVDC cable. More accurately, the power from Shetland has to reach the mainland via two long subsea cables and a switching station. All elements have to work or the whole system fails. There will obviously be some loss of energy because of the length of transmission required. Not surprisingly, in the face of considerable local opposition, SSE is expressing great confidence in the reliability of such a cable, as reported by Shetland Newsiv:

THE PROJECT director in charge of building the Kergord converter station and 600MW interconnector infrastructure linking Shetland to the national grid expects the subsea link to be available for 99.8 per cent of the time.

Curiously, however, the report in the Shetland News also goes on to say:

Lerwick Power Station will remain on standby, should the cable fail, until at least 2035.

A sensible precaution, or perhaps a sign of less confidence than the official line suggests? Also, given that the plan is that electricity is to be exported from Shetland to the mainland (which implies electricity surplus to Shetland’s needs), why the need for Lerwick Power Station to remain on standby? Oh I see – because wind power is unreliable, and if Shetlanders were forced to rely simply on the electricity generated by the wind farm, even in such a windy place, they would be left without power for significant periods of time.

SSE/Viking Energy may also have run into a new problem. According to the Energy Voice websitev:

Suspected unexploded ordnance has been found along the route of the planned subsea cable that will link Shetland to the mainland.

However, significant though that development might (or might not) prove to be, that’s a side issue. My purpose here is to take a look at the performance of HVDC cables to date, and to ask questions regarding the reliability of offshore and island wind farms as a source of steady power for the UK mainland National Grid.

Caithness – Moray HVDC Cable

SSE have been keen to cite the Caithness – Moray HVDC cable as an example of an earlier cable that hasn’t caused any problems.

In our experience with the Caithness to Moray cable – the most directly relevant one, which we installed in 2018 – we had no issues at all with the cable being damaged or being out of service.”

But is this so? Laid (in fact) in 2017, it appears that by 2018 problems had already become apparent. Because of the nature of the necessary remedial works, and the sensitive nature of the site, it was necessary for an Environmental Appraisal Report to be commissioned. Although elements of it have been redacted, it is available onlinevi.

From this we learn:

Scottish Hydro Electric Transmission Plc (SHET) have developed a High Voltage Direct Current (HVDC) electricity transmission link between Caithness (Noss Head) and Moray (Portgordon)… In early 2018, information became available that suggested there was a fault in the (offshore) installed cable. The location was identified as being at KP 13.158 (approximately 13km from Port Gordon landfall). A cable repair and associated activities were undertaken by NKT in early 2018.

The report was required in connection with additional works, identified as including the following:

Cable remediation and backfill at KP1.6‐3.6, including rock placement if required; Installation of 2 x new lengths of DC cables & 1 x FO of cable between KP11‐16 and potentially KP83‐86 (dependent on cable inspection results);

Cable de‐burial and inspection at KP 83‐86;

Burial of newly installed cable, use of rock placement if required; and

Removal of old cables at KP11‐16 and KP83‐86 (dependent on cable inspection results).

Maybe the claim that they had had no problems with the cable laid in 2018 involved a careful choice of words, if the problems all related to the cable laid in 2017, and not to a replacement cable laid in the following year?

Western Link HVDC cable

This cable has experienced numerous problems, as the Energyst websitevii makes clear:

The failure of the high voltage undersea cable between west Scotland and north Wales last month resulted in National Grid ESO paying almost £31m for wind farm operators to curtail output.

Consultancy Cornwall Insight calculated the figure based on Balancing Mechanism data and prices during what was an exceptionally windy month.

The Western Link HVDC cable went down on 10 January and remained offline until 8 February. It was the cable’s third complete trip in as many years.

So problematic has this cable proved to be, that:

Following the latest outage,Ofgem has opened a probe into the £1.3 billion Western HVDC connector, which links Highland wind farms via Hunterston to North Wales.

So far as I am aware, we still await the outcome of the Ofgem probe. Since the above article appeared (on 25th February 2020), there have been additional problems, with a further outage lasting from 15th February to 13th March 2021. Whenever a problem of this nature occurs, there are inevitably costs. As an online article from S&P Globalviii tells us:

Since the link went offline on Feb. 15, GB metered wind output has been sharply constrained, with output up to 2.1 GW lower than National Grid’s final forecasts, failing to outturn above 12 GW,” S&P Global Platts Analytics said March 3.

Within the Balancing Mechanism, the volume of accepted bids in Scotland reached 430 GWh in February, up from 46 GWh in January when the link was fully available, it said.

Between Jan. 1 and Feb. 15 National Grid reported daily average constraint costs of GBP0.5 million/day. This rose to GBP6.1 million/day from Feb. 16 to Feb. 25, before wind generation dropped.

“Balancing Services Use of System (BSUoS) charges – the cost of balancing the transmission system of which both generators and suppliers are liable – reached an intra-day high of GBP15.3/MWh on Feb. 25, the highest level since Dec. 27, 2020,” Platts Analytics said.

BritNed HVDC cable

As the UK increasingly phases out fossil fuels from its electricity generation programme, the need to import electricity from elsewhere becomes increasingly important. At the very moment I type this, a late summer’s evening in 2021, 17.4% of the UK’s electricity is being supplied via interconnectors, and (by chance – the number fluctuates) 3.5% of the whole of the UK’s electricity is at this moment being supplied via the BritNed HVDC cable, that is the interconnector between Britain and the Netherlands. It can readily be appreciated that this is an important cable. And yet it has an unhappy history. I can do no better than tell its story by quoting from an article which appeared on Watt-Logic’s websiteix on 17th March 2021:

The 1 GW BritNed interconnector linking GB with the Netherlands has suffered another fault and is expected to be out of service until late April, meaning it has spent much of this winter out of action. In addition to contributing to a tight GB market, these outages illustrate some of the challenges facing offshore electricity infrastructure, particularly in sub-sea environments.

BritNed tripped on 8 December and did not return to service until 9 February due to a cable fault. The damaged cable section was found approximately 100 km off the Dutch coast at a water depth of 40-50 meters. Repairs were successfully carried out within 29 days despite severe weather. But now the interconnector has developed another fault, probably with the cable again, and is expected to remain out of service until 22 April.

These outages mean that BritNed will have been offline for a significant portion of Winter 2020, a risky position given it holds a capacity market contract for the current delivery year. There have been two Capacity Market Notices (“CMNs”) issued this year, the second of which came just days before BritNed’s first outage. While a failure to deliver following a CWN [sic] does not attract penalties unless a Capacity Market Stress Event occurs, the issuance of both CWNs [sic] and Electricity Margin Notices this winter, combined with high price volatility, indicate the markets have been much tighter than usual.

By the way, please see “Counting the Cost”x for an explanation of Capacity Markets.

Orkney – Pentland East cable

This cable was replaced in late 2020 and the announcement of the completion of the work was welcomed with much publicity from SSE and others. However about 2 months later it was very quietly announced that the new £30 million cable had unexpectedly failed.

There is as yet no word on whether or not it is to be repaired, as the old one was reconnected, at considerable expense. We can only assume that the cable failure was catastrophic.

As I understand it, Ofgem have conditionally approved a larger capacity cable to Orkney, with final approval depending on enough wind farm capacity being approved to justify the cable. Perhaps if the larger cable is fully approved, SSE will simply write off the failed cable. Presumably they are hoping that the old, reinstated cable lasts until the larger cable is approved.

Whether or not this speculation is correct, this is all on the back of pre-existing problems that were reported by the Orcadianxi in 2019.

Western Isles

This is a particularly dismal story. On 16th October 2020 the cable linking the Outer Hebrides to Skye was cut, causing a blackout affecting 18,000 Hebridean homes. The Guardian reported on it at the timexii:

The 20-mile (32km) cable, which runs on the sea bed from Skye to Harris, failed without warning six days ago.

That forced Scottish and Southern Energy Networks to call on a diesel-fuelled power station in Stornoway to provide back-up electricity, and airlift extra diesel generators from the mainland in case Stornoway’s turbines fail.

SSEN announced on Thursday that the 33,000V cable was unrepairable, adding that it could take between six months and a year before a new cable could be commissioned and laid.

It believes the breach happened at a depth of over 100 metres about 15km offshore from Skye, and is now investigating whether it was cut by a trawler or another vessel. SSEN has asked for local shipping records so that it can pinpoint which vessels were in the area at the time the cable failed.

When the cable failed, a larger replacement cable was requested by many interested in the issue. However SSE do not have much wind farm interest in the Western Isles, and whether or not that influenced them, the larger cable request was rejected. It is worth noting that, when the cable failed, there was an adverse impact on some smaller community based wind farm projects: they could not market the electricity that they were producing, without the cable, and they lost income as a result. These smaller projects were not eligible for constraint payments.

I haven’t yet been able to find confirmation that the replacement cable is operational, though I believe it arrived in May, and the plans were that it should be in place by the end of August 2021.

Gwynt y Môr wind farm

This story confirms the problems, but from a slightly different point of view. As reported on the New Power websitexiii the company that owns the link to Gwynt y Môr wind farm argues that a series of repair outages required following a cable failure in October 2020 should be underwritten by consumers because insurers are leaving the market.

The company notes that the cost of insurance has risen 40 per cent in the past two years and many insurers have declined to provide cover. Offshore wind farm cables have been under the spotlight for outages to repair cable problems, due to manufacturing faults, accidents and other issues.

In April this year, Danish wind farm operator Orsted said it had put aside £350 million to repair or replace cables within its wind farms that had been damaged due to interaction with the sea floor.


Subsea cables fail for many different reasons, including the activities of fishing trawlers, damage from anchors, manufacturing errors, and environmental factors (e.g. seabed roughness and tidal flows) leading to corrosion and abrasion of the cables.xiv Only a few days ago it was reportedxv that the Australian authorities have arrested the Ukrainian master of a Maersk container ship for allegedly damaging a telecommunications cable connecting Singapore and Western Australia, with the ship’s anchor. In that case the cable affected related to telecommunications, and was not an HVDC cable, but the principle remains the same. These cables are vulnerable, and not just in theory – the brief case history above illustrates that the problems are real in practice too.

It’s bad enough blighting beautiful island landscapes with industrial scale wind turbine developments. It compounds the issue when the benefits claimed for them hang by such a fragile thread.

i https://en.wikipedia.org/wiki/High-voltage_direct_current

ii https://cliscep.com/2021/06/29/for-peats-sake/

iii https://cliscep.com/2021/07/06/utilities-futility/

iv https://www.shetnews.co.uk/2021/08/19/subsea-cable-very-reliable-says-project-director/

v https://www.energyvoice.com/renewables-energy-transition/344908/suspected-unexploded-ordnance-found-along-route-of-planned-shetland-hvdc-link/

vi http://marine.gov.scot/sites/default/files/environmental_appraisal_-_redacted_0.pdf

vii https://theenergyst.com/western-link-failure-sees-national-grid-pay-31m-to-turn-off-wind-farms/

viii https://www.spglobal.com/platts/en/market-insights/latest-news/electric-power/030521-uks-western-hvdc-link-due-back-in-service-week-starting-march-15-nat-grid

ix http://watt-logic.com/2021/03/17/another-britned-outage-illustrates-the-risks-of-the-current-offshore-infrastructure-regime/

x https://cliscep.com/2021/08/15/counting-the-cost/

xi https://www.orcadian.co.uk/power-cable-fault-results-in-rackwick-work/

xii https://www.theguardian.com/business/2020/oct/22/scottish-energy-company-ssen-investigates-blackout-caused-by-subsea-cable-failure

xiii https://www.newpower.info/2021/08/gwynt-y-mor-reveals-battle-to-insure-offshore-wind-cables-40-premium-hike-and-scores-or-providers-decline/

xiv https://www.prosperoevents.com/why-subsea-power-cables-fail/

xv https://www.poandpo.com/news/maersk-ship-captain-charged-over-underwater-cable-damage-off-perth/


  1. 25 Aug : SSEN Transmission responds to subsea cable concerns
    “The Caithness-Moray HVDC link, which has been operational since January 2019,
    currently has a 99.8 per cent availability rate, having been unavailable only during pre-planned outages.

    “The Shetland HVDC link, which is scheduled to be fully operational by 2024,
    has been designed to be protected against potential damages
    and will be buried in the sea bed via a remotely operated submersible units
    which cut the trench in which the cable is laid at a specified depth, which is then covered by protective materials.”


    That is contradicted by a reader’s letter on Aug 23, which lists breakages and outages


  2. “Lerwick Power Station will remain on standby” which means that someone has to pay for this perfectly good source of power to sit idle but be available while money is flushed away elsewhere. Thank you for a great summary of the problem with cables.


  3. ‘Subsea cables fail for many different reasons…’

    Including Brexit, natch:



  4. Vinny, interesting link – thanks. I vaguely remember the story at the time. A quick search of the internet does indeed suggest that the project has been dead since at least 2019. I very much doubt it was Brexit that killed it – more likely the expense and sheer unfeasibility of the scheme would be my guess.


  5. Moyle interconnector:


    “In August 2011, the interconnector went out of service. Repairs were made and the cable became operational again with 450 MW in February 2012. However, further faults meant that a major part of the interconnector had to be taken out of service until it could be augmented with the additional return cables, completed in 2016. This restored capacity to the full 500 MW.

    In February 2017, the cable suffered another fault, halving capacity to 250 MW. However full capacity was restored in September 2017, following repairs by Nexans.”


  6. “Tasmanian Government Wants Compo Over 2015-16 Basslink Failure”


    “The Tasmanian government has threatened to take legal action against the operators of a Bass Strait electricity cable, Basslink, that failed and contributed to an energy crisis in the state.

    Energy Minister Guy Barnett said on Thursday the government believes it is entitled to damages over the Basslink outage in December 2015.

    “The state proposes to initiate the dispute next week unless Basslink agrees to compensate it for its losses,” he said in a statement.

    At the end of last year, Basslink rejected an analysis of its subsea cable outage of 2015-16 released by Hydro Tasmania that said the subsea cable was pushed beyond its design limits.

    “The DNV GL analysis indicates that the cable had been operated by BPL in a manner that allowed it to exceed its temperature design limits during a number of periods in its service life. This overheating and subsequent cooling of the cable has resulted in degradation of the cable,” Hydro Tasmania said at the time.

    “DNV GL concluded that the cable failure was the probable result of electrical energy discharge within the cable as a result of polarity reversal and cooling shortly before the 20 December 2015 cable failure.”

    Basslink retorted that the report merely put forward one idea and did not provide any “conclusive and definitive proof”.

    “Hydro Tasmania’s experts did no actual testing on the Basslink cable or any similar HVDC [high-voltage direct current] cables. They used a theoretical model based on certain assumptions to come to a set of conclusions,” Basslink CEO Malcolm Eccles said. “These assumptions make the experts’ conclusions speculative and not based on actual facts.”

    The Basslink Interconnector was down between December 2015 and June 2016, with the fault discovered 90.5km from the Tasmanian coastline, and removed and capped three months after going down.

    Basslink completed its cable joint repairs in June 2016 following months-long delays due to excess water damage.”


  7. Skagerrak:


    “The 240-kilometre (150 mi) Skagerrak 1–3 scheme consists of a 113-kilometre (70 mi) overhead line and a 127-kilometre (79 mi) underwater cable.”

    “Skagerrak 2 repair, Norway – Denmark
    The national power grids between Denmark and Norway are connected through four DC-links crossing the Skagerrak strait, capable to carrying 1700 MW of renewable energy to the two countries’ energy mix. One of the cables, the Skagerrak 2, was damaged due to external impact. The damaged part was located about 36.5 km north of Bulbjerg in Denmark.”


    Keep looking, and more and more examples of failure are there to be found.


  8. Mark – thanks for the digging on this “Fishy” topic.

    my only question is – as they are buried in the seabed & rocks laid to protect them, how do they get “damaged due to external impact” ?

    or am I missing something (dragnets etc) !!!


  9. or – “conspiracy theory alert” – Russian Subs with big snipper like things attached !!!


  10. Thanks also from me Mark. I have failed to respond so far because I wanted to look up in Future Energy Scenarios what the future holds for us re: interconnectors. The first interesting thing to note is:

    GB becomes a net exporter of electricity by 2040 in all scenarios

    Net export in 2050 seems to range (reading from the graphs) from 0-150 TWh, depending on scenario. (Dudgeon, remember, generated 1.7 TWh last year).

    There is a large net export of electricity over the interconnectors across the year; this helps manage renewable generation output and meet peak demand.

    –System Transformation scenario

    The question arises: are other countries also generating Net Zero scenarios where the excess juice they make from renewables are exported? I can’t help thinking that when we need the juice, so will they, and when we won’t, they won’t. (Allowing a 1-hour shift in peak demand, etc.) Will our friends say “Non!”

    And all a nefarious state or organisation, SPECTRE, etc, would have to do to discombobulate us would be to “accidentally” drag an anchor for a significant distance.


  11. dfhunter – the short answer is that I don’t know. However, manufacturing errors and corrosion (from salt water) are both possible even in buried cables. I suspect that long cables aren’t entirely covered in boulders for protection (imagine the size of that task!), so significant lengths of cable are probably vulnerable to damage from drag-nets, anchors etc.

    I tend to prefer cock-up over conspiracy theory, but given that the authorities make the position of cables known (so that anchors and drag-nets can – in theory, at least – avoid them), there must be a large risk of hostile actors, to whom the information is readily available, being able to damage them if they want to.

    I don’t want to over-state the problems, but given the track record of cable failures, problems there undoubtedly are.


  12. Why are we having to rely on a bunch of amateur journalists to do all of the heavy lifting here? Why couldn’t someone who is getting paid have done Mark’s job for him?


  13. Update:

    “Faulty 19 mile-long Harris to Skye subsea cable replaced”


    “A subsea electricity cable between the islands of Harris and Skye affected by a fault last October has been replaced.

    The new 33 kilovolt (kV) cable has gone live following a £28m project by energy company SSEN Distribution.

    Since October, customers on Harris have been supplied with electricity by back-up power stations at Battery Point and Arnish on Lewis.

    The fault also stopped power being exported from Lewis and Harris renewable schemes to the mainland grid.

    The new cable runs from Beacravik on Harris to Ardmore on Skye. Beaches dug up at both locations during the work have been reinstated to their “natural state”.

    SSEN Distribution said repairing the broken cable was ruled out because the fault had occurred on part of the powerline 100m (382ft) underwater.

    The company said laying the new cable had required “significant offshore work” using specialist marine vessels.”

    What the BBC article omitted to mention (must have slipped the journalist’s mind) is that the replacement cable came from China.


  14. Latest on the planned interconnector for the Viking Energy wind farm on Shetland:


    “This consultation sets out our views on our assessment of SSEN Transmission’s proposed costs for delivery of the Shetland HVDC Link project.”

    The consultation end date is 4th October 2021.

    The executive summary within the consultation document includes this:

    “In November 2020, we received a ‘Project Assessment’ submission from SSEN Transmission, for its proposed Shetland HVDC Link project (the Shetland Link). The project will provide an electricity transmission connection between the Scottish mainland and the Shetland Isles.

    This consultation is seeking stakeholder views on our proposed efficient cost allowances for the Shetland Link, as well as our proposed modifications to SSEN Transmission’s licence to support delivery of the project.

    The link will be a 600MW single circuit connection that serves the dual purpose of exporting renewable generation from windfarms on and around the Shetland Isles to the mainland and providing a new secure supply connection to Shetland as the Lerwick Power Station reaches its end of life.

    SSEN Transmission submitted its initial costs for delivering the Shetland Link to Ofgem in November 2020, amounting to £657.8m. As discussed and agreed with us, it provided further updates to those costs in May and August 2021, bringing the costs to £675.4m. We are minded to provide an ex-ante allowance of costs of £628.6m for delivery of the project, which constitutes a reduction of £46.8m (6.9%) to SSEN Transmission’s submitted costs. This proposed reduction is the result of our careful review of SSEN Transmission’s submitted costs over the past eight months, including benchmarking those costs against similar projects and our detailed assessment of SSEN Transmission’s contracting and risk management strategy.”

    Interesting planned costs reduction. Watch this space.


  15. “Interesting planned costs reduction”

    are you sure that’s what the Ofgem statement means ?

    as ever I had to look up the meaning for “ex-ante” & got lost in the long grass of definitions !!!


  16. dfhunter, I’m not sure of anything where ofgem is concerned. The document is lengthy and, as you say, is peppered with definitions, none of which makes it easy. However, subject to watching this space for possible alternative developments, I’m content for now to take “a reduction of £46.8m (6.9%) to SSEN Transmission’s submitted costs” at face value.


  17. What’s interesting in this context is the Anglia One winfarm was originally going to have a +/- 300kV DC system because of the long run (down to Bawdsey & then overland to Bramford 400kV station). What they seem to have ended up with is 220kV 3 phase AC. Dunno what that does to the power factor loss in the capacitance but I guess they must have thought the TCO was better with AC.


  18. “Fire shuts one of UK’s most important power cables in midst of supply crunch
    Coal plants being warmed up as market prices surge to £2,500 per MWh from a norm of £40”


    “A major fire has forced the shutdown of one of Britain’s most important power cables importing electricity from France as the UK faces a supply crunch and record high market prices.

    National Grid was forced to evacuate staff from the site of the IFA high-voltage power cable, which brings electricity from France to a converter station in Kent, where 12 fire engines attended the blaze in the early hours of Wednesday morning.

    The fire has halted electricity imports via the 2,000 megawatt power cable until March next year and could not have come at a worse time for the UK’s squeezed markets, according to experts. The UK faces record energy prices after a global gas market surge raised the cost of running gas power plants, which has been compounded by a string of power plant outages and low wind speeds.

    The all-time energy price highs are expected to send bills soaring for the next year and cause a string of small energy companies to go bust. It has already forced some steelmakers to shut their factories during hours of peak electricity demand.

    The market price at one of the UK’s main electricity auctions cleared at a record price of £2,500 per megawatt-hour for the hours of peak demand on Wednesday, compared with a typical baseload price of about £40/MWh throughout 2019 and 2020.

    Phil Hewitt, a director of the market consultancy EnAppSys, said the fire was “a major event” because it could lead to an extended outage at the IFA cable.

    “It puts the GB market in a risky position for the winter and especially if we suffer from periods of low wind and cold temperatures,” he added.

    The electricity system operator, which is owned by National Grid, said there would be enough electricity to meet the UK’s peak demand on Wednesday evening. However, market experts fear the latest blow to the UK’s power system could cause prices to rise further and will increase the UK’s reliance on running its last remaining coal plants.”

    Of course, all this stuff is linked up. I could just as relevantly have posted this as a comment on “Counting the Cost”. We can join the dots. Why can’t the Guardian, BBC, and most importantly, the politicians?


  19. The BBC has caught up now, too:

    “UK power prices soar after key cable hit by blaze”


    “A key electricity cable between Britain and France has been shut down, sending wholesale energy prices soaring.

    National Grid said a fire and planned maintenance at a site near Ashford in Kent means the cable will be totally offline until 25 September.

    Half of its capacity, or one gigawatt (GW) of power, is expected to remain unavailable until late March 2022.

    On Wednesday, British electricity prices for the following day jumped by 19% to £475 per megawatt hour (MWh).

    The fire at the Interconnexion France-Angleterre (IFA) site broke out in the early hours of Wednesday. The site was evacuated and there were no reports of casualties.

    After the fire an electricity interconnector running under the English Channel was “not operating”, the National Grid said in a statement.”

    Although the failure is significant, the headline does a disservice to the truth by trying to suggest that that prices soared after, i.e. because of, the blaze that prevented the cable from importing electricity from France. As is made clear further in to the report, prices were already soaring, because of the ridiculous electricity generation system we have in place, it’s just that the energy crisis (funny they never use the words “crisis” or “chaos” in this context) was exacerbated by the cable failure:

    “The link can carry up to 2GW of power, and had been importing electricity from France in recent days, after UK prices hit a record high of £540 per MWh on the wholesale energy market.”

    Not a mention anywhere of the shambolic electricity generation system we have in this country, thanks to over-reliance on unreliable sources of energy generation, and a pointlessly complex system of regulation, plus reliance on imports.


  20. I’ve commented on the BBC story, by way of Cliscep community outreach. (Politely, in reply to comments on proposed solutions.)

    We seem to have a good system going here, so long as the goal is to increase prices, decrease stability, and ultimately trigger failures. It seems we have cut out more and more of the grid’s reliable bits, and fixed the resulting gaps with brown paper and bits of string.

    Is this concentrating any minds among those whose opinions might actually have the possibility of making change? Or are we locked onto a path that takes us to inevitable crisis?

    I find it interesting that I disparage the use of the word “crisis” as it pertains to climate change, but reach for it now in connection with our electricity grid. The question is, are my fears of the consequence of climate change policies any more valid than others’ fears of climate change itself?

    Liked by 1 person

  21. Update:



    “SSEN, part of SSE PLC, has completed a project to replace the subsea electricity cable between Skye and Harris, following a cable fault in October last year.

    Teams from Scottish and Southern Electricity Networks (SSEN) Distribution connected and energised the new cable this week before gradually returning the network to normal operation – reconnecting Lewis and Harris to the mainland electricity network.

    The £28 million cable replacement project involved significant offshore works using specialist marine vessels – the Maersk Connector and Grand Canyon 3 – working with principal contractor, Global Offshore, to successfully install and protect the 33 kilovolt (kV) cable between Ardmore, Skye and Beacravik in Harris.

    The project included land-based works at each shore end to connect the new cable to the existing electricity network and restore local beaches at Ardmore and Beacravik to their natural state.

    Since October, Battery Point and Arnish Power Stations on Lewis have been running at full-duty operation, alongside on-island renewable generation, to ensure a safe, secure and reliable supply of electricity to local homes and businesses. These stations will now return to back-up operation.

    “While reliability of power supplies has been maintained, we recognise the impact to the community as a result of this fault and would like to thank stakeholders, including local generators and wider community partners for their continued patience and engagement during the fault period.

    “I’d also like to thank our teams in our operational centres, power stations and contract partners for their ongoing commitment during a highly complex operation to help keep the power flowing and restore the network.”

    As part of its draft business plan for the next price control period, RIIO-ED2, running from 2023 to 2028, SSEN Distribution is proposing a number of strategic subsea investment projects in the Western Isles, including an upgrade to the circuit between Skye and Uist.

    SSEN Distribution continues to assess the future resilience and electricity demand needs for customers and communities on Lewis and Harris. This includes close liaison with SSEN Transmission on its proposed 600MW HVDC transmission link to the Western Isles, which remains subject to developer commitment and regulatory approval.

    A third-party study will be carried out prior to SSEN Distribution’s final business plan submission in December to assess options, including the installation of a second 33kV cable between Skye and Harris, if the current transmission needs case is not taken forward. All plans will be subject to regulatory approval.”

    Liked by 1 person

  22. “CPS failures on Orsted’s offshore wind farms”.


    I can’t cut and paste, because it’s a subscriber-only website. However, the gist is that Orsted has identified Cable Protection System (CPS) problems at three offshore wind farms – Burbo Bank Extension, Westernmost Rough, and Walney Extension Array, and has consequently had to apply for licences from the Marine Management Organisation to repair or replace CPS at all three “farms”.


  23. “Full power ahead for UK to Norway under-sea power cable”


    “The world’s longest under-sea electricity cable, transferring green power between Norway and the UK, has begun operation.

    The 450-mile (725km) cable connects Blyth in Northumberland with the Norwegian village of Kvilldal.

    At full 1,400 megawatt capacity it will import enough hydro-power to supply 1.4 million homes, National Grid said.

    National Grid Ventures president Cordi O’Hara said it was a “remarkable feat of engineering”.

    She added: “We had to go through mountains, fjords and across the North Sea to make this happen.

    “North Sea Link (NSL) is also a great example of two countries working together to maximise their renewable energy resources for mutual benefit.”

    National Grid said the €1.6bn (£1.37bn) joint venture with Norwegian power operator Statnett would help the UK reduce carbon emissions by 23 million tonnes by 2030.

    It has four other power cables running to Belgium, France and the Netherlands and said 90% of energy imported in this way would be from zero carbon sources by 2030.”

    There’s so much wrong with this piece.

    “…the Netherlands and said 90% of energy imported in this way would be from zero carbon sources by 2030.” That ignores the fact that much of the electricity coming through the Dutch interconnector is far from “zero carbon” just now. I should have though an analysis of that issue might have been worthwhile, rather than just cutting & pasting the press release.

    Furthermore, the timing of the completion of the Norwegian interconnector is exquisitely awful, since Norway isn’t really in much of a position to export to the UK any hydro-generated electricity just now:

    That might just have been mentioning too, but if it had been, the BBC wouldn’t have been able to give it the uncritical flattering piece of PR that was obviously intended, ahead of COP 26.


  24. I thought they’d been running it for a few weeks now
    but they are calling that testing
    On 23/9/21 they ran 0.43GW through it for a bit then back to zero
    The Friday morning they ran it up from zero to 0.63GW where is has sat since
    Unfortunately for them, now they don’t need it as currently the UK has too much wind.

    Liked by 1 person

  25. “Mesmerised brown crabs ‘attracted to’ undersea cables
    Research in Scotland shows animals freeze near the electromagnetic field with implications for metabolism and migration”


    “Underwater power cables mesmerise brown crabs and cause biological changes that could affect their migration habits, scientists have discovered.

    The cables for offshore renewable energy emit an electromagnetic field that attracts the crabs and causes them to stay where they are.

    A study of about 60 brown crabs at the St Abbs marine station in the Scottish Borders found that higher levels of electromagnetism caused cellular changes in the crabs, affecting their blood cells.

    Alastair Lyndon, an associate professor at Heriot-Watt University’s centre for marine biology and diversity, said: “Underwater cables emit an electromagnetic field. When it’s at a strength of 500 microteslas and above, which is about 5% of the strength of a fridge door magnet, the crabs seem to be attracted to it and just sit still.

    “That’s not a problem in itself. But if they’re not moving, they’re not foraging for food or seeking a mate. The change in activity levels also leads to changes in sugar metabolism – they store more sugar and produce less lactate, just like humans.”

    The researchers used the marine station’s purpose-built aquarium laboratory for the experiment. Kevin Scott, the manager of the St Abbs facility, said: “The aquarium lab is composed entirely of non-metallic materials, which means there is minimal electromagnetic interference.

    “We found that exposure to higher levels of electromagnetic field strength changed the number of blood cells in the crabs’ bodies.

    “This could have a range of consequences, like making them more susceptible to bacterial infection.”

    The team warned that changes in the species’ behaviour could hit fishing markets, as the crabs are the UK’s second most valuable crustacean catch and the most valuable inshore catch.

    A number of offshore wind farms are installed or planned around Scotland’s coast, requiring extensive underwater cabling, and researchers said further work is needed to ensure they do not destabilise Scotland’s brown crab population.”


  26. “Kent’s burnt-out electricity cable will take two more years to get back to full service
    Lost capacity will compound UK’s energy woes while ‘extensive work’ is carried out on French connection”


    “One of Britain’s most important electricity import cables will not return to full service for another two years after a fire forced it to shut, compounding the UK’s energy woes ahead of a looming winter crunch.

    The blaze at the Sellindge converter station in Kent forced a shutdown of the high-voltage cable that brings electricity from France to the UK last month as energy markets rocketed to all-time highs amid global energy supply difficulties.

    National Grid, which owns the 2,000 megawatt cable, expects half of its capacity to return to service on Wednesday but said “extensive work” would be needed to bring the power link back to full service.

    The FTSE 100 energy company hopes to bring another 500MW of capacity back to service between October 2022 and May 2023, meaning the cable will be running at three-quarters of its capacity through that winter.

    The cable, known as the IFA Interconnector, will finally return to full service after further work, which National Grid hopes to complete by October 2023.

    “We are completely focused on getting IFA safely returned to service as soon as possible and ensuring we are able to support security of supply,” the company said in a statement.

    The shock shutdown of the subsea cable sparked concern among industry experts over Britain’s energy supplies during record high market prices across Europe.

    Phil Hewitt, a director of the market consultancy EnAppSys, said at the time that the fire was “a major event” that would leave the UK “in a risky position” this winter “especially if we suffer from periods of low wind and cold temperatures”….”.

    Liked by 1 person

  27. “How to plug the UK into desert sunshine”


    “If you wanted to build a gigantic new solar farm, you would probably choose the desert over Dartmoor.

    Many have dreamed of exploiting the desert sun, but one of the challenges has always been how to export that electricity.

    Xlinks, an energy start-up, says it has the answer with the world’s longest under-sea power cable.

    A total of four cables are planned to snake for 3,800km (2,360 miles) along the seabed from a solar and wind farm in Morocco past Portugal, Spain and France, before landing in the Devon village of Alverdiscott.

    “It’s absolutely doable,” insists chief executive Simon Morrish. His firm hopes to have the project up and running by the end of the decade.

    If all goes to plan, Xlinks’ cable will provide 3.6 gigawatts of electricity, enough to power seven million homes, for 20 or more hours a day. It will join several similar, if shorter, lines that connect the UK’s electricity grid to neighbouring countries.

    Energy firms plan to establish even more under-sea power cables here and in other places around the world in the coming years. But what does it take to install them?

    And with one connection between France and the UK recently knocked out of action due to a fire, are these cables really going to provide reliable sources of energy in the future?”

    Good question. The article goes on:

    “Prof David Flynn at Heriot-Watt University says we are witnessing the start of a “boom time” in the under-sea power cable industry. That’s partly thanks to heightened spending by various governments on renewables during the pandemic, in a push to accelerate job growth and decarbonisation.

    These power lines are not just important for countries seeking to link their grids together – offshore wind farms, which are ever more popular, require under-sea cables, as well.

    The recently completed North Sea Link, a 1.4 gigawatt connection between the UK and Norway, currently holds the title of world’s longest under-sea power cable. At 720km, it is less than a fifth of the length of the cables required by Xlinks. However, North Sea Link had particularly challenging obstacles in its way at the Norwegian end, including a landlocked lake, a mountain and steep fjords.”


    “Installing any under-sea power line requires care, she explains, because the cables can only bend so much before they become damaged. As such, they must be gently lowered into position in favourable weather.

    Plus, there are lots of other cables and pipelines on the seabed. You can’t just dump new power lines over them without permission. Special structures sometimes have to be put in place in order to allow one cable to cross another, for instance. North Sea Link had to negotiate almost 100 crossings between Norway and the UK, says Mrs Opiyo-Mullings.

    The next under-sea cable, Viking Link, will connect the UK to Denmark’s grid. At 760km, it will be longer in terms of total length than North Sea Link, though a significantly larger portion of it, about 140km, will pass over land either in the UK or Denmark. That too requires careful planning, so small tunnels can be bored underneath roads and other infrastructure, for instance.

    We should be cautious about the proliferation of under-sea power cables, says Prof Flynn. For one thing, there could be negative environmental consequences of increasing activity on the seabed.

    One study recently found that brown crabs were mesmerised by under-sea electricity cables off the coast of Scotland, which could negatively affect their mating and foraging.

    Plus, what if multiple cables get damaged by anchors or debris rolling around on the seabed? Or, worse, an adversary decides to sabotage them?”

    A reasonably balanced article for a change.


  28. Mark Hodgson says:
    “How to plug the UK into desert sunshine”

    I seem to remember a plan to link the UK with Iceland to tap into their geothermal capacity. It seems to me that an Iceland, if. it was feasible, would be much more useful to the UK as it could provide baseload power from a dedicated facility.


  29. Bill, yes, the Iceland idea seems to have disappeared without trace. Subject to all the technical difficulties associated with it, I’d say from the point of view of baseload and grid stability it makes a lot more sense than a connection to Moroccan solar panels.


  30. A view from the USA:

    “Silence from Shoreline Press on Undersea Electric Problems”


    “ALL THE EXCITING PRESS about the installation of windfarms focuses on the seemingly blithe turbine blades swirling innocently in the free breeze offering efficient, economical and carbon imprint free electricity to the east coast of the United States.

    That is the mantra offered by Baker, Raimondo, Lamonte and Cuomo. And to make sure no one sings off key the public is reminded of the tens of thousands of jobs and commercial contracts that attend to this wonderful new age. Cementing that certainty is the new president Biden naming Raimondo to Commerce so that NOAA doesn’t get up on its high horse and start to discuss the real harm marine wind installations can and will cause marine ecology, to say nothing of wrecking a significant portion of the commercial fishing industry….

    …You’ve got Google (I didn’t say you wanted it. I just said you had it)—go ahead and look at the wind industry cable laying engineering press about the hazards and certainty of cable failure and associated costs to find and repair. And the attendant financial impact of down time when electricity is not being delivered. The news is not good, none of it.

    The necessary undersea electric cables that connect the swan like turbines to the shore are viewed by the wind industry itself as their Achilles Heel. While the cost of cable laying is estimated at only 10 to 15 percent, it has shown in its 15 year European and Asian experience (over 5,000 turbines planted in someone’s ocean with maybe 10,000 miles or more of cable laid on ocean floors) it has run up more than 80 percent of the insurance claims the wind industry has filed. In 2020 the numbers worldwide have not gotten much better.

    The marine environment in the northwest Atlantic is considered the harshest of places on the planet to place any undersea cable—let alone the three thousand miles Avangrid and its gaming table player partners are set to do on the Vineyard Wind project alone.

    It has already shown its ugly face in the functioning of the five turbines off Block Island. The cables to the island, and to the mainland, have become unburied from the sandy ocean bottom there and will require a complete reengineering with tunnels drilled 30 feet into ocean bottom and then laterally several thousand yards offshore in order for them to stay put.

    This has placed an unexpected $80 million repair bill (just five turbines, mind you, and less that 18 miles of cable) on the rate payers. Orsted, which has bought the Rhode Island wind company, has publicly said “we do not discuss our financial matters.” National Grid, which owns the grid acknowledged it will absorb the $50 million repair bill.


    As a side note the RI Public Utilities government panel had advised the deeper and more expensive installation should be used in the first place. Their advice was brushed aside. Now the cost of each turbine has upped $15 million. People get paid to think like this?

    The tiny Block Island Times newspaper has made much of this reporting in detail the costs and the culprits. But it doesn’t seem of interest to the Narragansett Times in the shoreside town where the cables land. And dead silence when it arrives in Providence for the Providence Journal.

    The repair will take two years, and a large swath of ocean is closed to commercial fishing—blues, sword, squid, lobster, clams, flounder, haddock. No fishing! And this mistake was entirely not of nature’s making. Wait until she wades in (no pun intended) off Martha’s Vineyard….”


  31. No great surprises here:

    “Decision on our Shetland HVDC Link Project Assessment”


    “This document confirms our decision to provide SSEN Transmission with a total capital cost allowance of £641.8m for the delivery of the Shetland Link and sets out the details of the Large Project Delivery (LPD) mechanism that will apply to this project.

    We also set out our decision on the licence modifications required to support the delivery of the Shetland link. To that end, we have issued a notice of licence modification in appendix 2 of the document as part of this publication.

    SSEN Transmission submitted its initial costs for delivering the Shetland Link to Ofgem in November 2020, amounting to £657.8m. As discussed, and agreed with us, it provided further updates to those costs in May and August 2021, bringing the submitted costs to £675.4m. We have decided to provide an ex-ante4 allowance of costs of £641.8m for delivery of the project, which constitutes a reduction of £33.6m (5.0%) to SSEN Transmission’s submitted costs. This decision is the result of our careful review of SSEN Transmission’s submitted costs over the past 12 months, including benchmarking those costs against similar projects, our detailed assessment of SSEN Transmission’s contracting and risk management strategy, and consideration of responses to our 03 September 2021 consultation: ‘Shetland HVDC Link Project Assessment”….”.

    And they keep telling us that renewables are cheap!


  32. On the other hand:

    “Energy firms fined after subsea cable delay pauses Scottish windfarms
    Turbine sites paid to switch off on windy days because there was no way to transmit power to south of UK”


    “Two energy companies will pay a record £158m fine after delays to a major subsea power cable bringing renewable energy from Scotland to England and Wales caused home energy bills to rise.

    National Grid and Scottish Power agreed to pay the penalty after an investigation by the industry regulator found many of Scotland’s windfarms were paid to turn off on windy days because there was no way to transmit the clean electricity to areas of high energy demand in the south of the UK.

    The £1.2bn power cable known as Western Link was expected to carry enough electricity to power 2m homes over 260 miles, mostly under water, from Scotland to England from late 2015, well ahead of its late 2017 deadline from the regulator.

    But the project was dogged by delays and was only ready more than three years later, in the summer of 2019, to help the UK make better use of its renewable energy generation.

    During the delay the cost of turning off windfarms, and running alternative power sources such as gas and coal plants, was ultimately shouldered by households through their energy bills.”


  33. “Power firms to pay £158m over Western Link delays”


    In fairness to the almost-sceptical Douglas Fraser at the BBC. he provides rather more nuanced information than does the Guardian:

    “There are eight big transmission cables exporting Scottish renewable power across the border, and importing it when the wind drops.

    The importance of that security of supply becomes even more important as Hunterston nuclear power station enters its final month of production.

    So big electric bootstraps to the east and west are required. The 530-mile link between Ayrshire and the Welsh border pioneered that length of high-voltage subsea cable.

    It proved to be a stretch for the companies contracted to supply the cable. It arrived late, it was faulty and sections had to be repaired. It didn’t help that there was a fire in the equipment at the Hunterston landfall site.

    So the contracting companies which face a huge hit in Ofgem redress have already seen around £100m of that in compensation from their contractors.

    The lessons learned should help with two more bootstraps, which should be nearing the Ofgem approval stage. One is planned for Peterhead in Aberdeenshire to Hawthorn Pit, a substation in County Durham. The other would link East Lothian with Drax, the giant biomass and ex-coal power plant in North Yorkshire.

    Together, they could cost £3.4bn, making them the biggest transmission investment Britain has ever seen.

    And with huge new windfarms being built offshore, there’s a lot more cable yet to be laid which will link them up.”


  34. This is more “20,000 volts under the ground,” but still.


    “More than 80 Norfolk parishes protest against wind farm plans”

    They are worried about the years of disturbance from cable-laying works. Personally I think that is a relatively minor issue, since it is very much temporary. The parishes are moonshotting for offshore grid connections instead. Curiously they are also worried about the effect of the works on land birds without giving a fig about the seabirds that are actually going to get swatted. I note also that considerable bribes are being offered to local communities:

    Vattenfall says it will “minimise” impacts to residents and wildlife and says the technology to connect offshore is not yet viable. It also points out the farms will bring investment to the region with a £15m pot for community projects announced last week.

    Vattenfall’s Head of Stakeholder Engagement gives lectures in her biker jacket, so that’s certainly innovative.


  35. “Western Link issues spark fresh concerns about Shetland HVDC link
    Issues with a major subsea cable project have ignited fresh fears about plans for a major project to hook Shetland up to the UK’s electricity grid.”


    “Issues with a major subsea cable project have ignited fresh fears about plans for a major project to hook Shetland up to the UK’s electricity grid.

    Local campaigners have highlighted faults with the Western Link scheme and the potential for similar problems to arise with the planned Shetland link.

    Similar concerns were voiced earlier this year after problems arose during work to replace one of the two electricity distribution cables connecting Orkney to the mainland.

    The Western Link scheme
    National Grid and Scottish Power Transmission recently agreed to pay a record redress package of £158 million for delays to the £1.2 billion Western Link scheme.

    The 262-mile subsea high-voltage direct current (HVDC) cable runs from Ardneil Bay in Scotland’s west coast to the Wirral in England, allowing electricity to be transported around the UK.

    But it has been plagued with issues, including a two-year delay and outages, which has led to constraint payments falling on the taxpayer.

    And the “multiple faults” with the cable that were picked up by the energy regulator are causing anxiety for some residents in Shetland, given a similar scheme is ongoing there.

    Shetland HVDC link
    Plans were approved by Ofgem last year to lay a 200-mile interconnector between the island and the mainland.

    It is aimed at maintaining security of supply to Shetland, with the Lerwick Power Station due to shut in 2025.

    It will also allow for renewable energy to be transported off the island, which is home to SSE Renewables’ Viking wind farm – its due to start up production in 2024.

    But the prospect of relying on a vast subsea cable for power doesn’t sit well with some Shetlanders.

    Frank Hay, head of local group Sustainable Shetland, said: “Cable problems are of particular interest to us because of the length of the cable to Shetland and the probability of issues with it.

    “In our opinion, Ofgem is failing to ensure value for money to consumers and the whole national energy supply situation is becoming chaotic. The headlong dash for green energy without properly ensuring security of supply is very worrying.

    “Here in Shetland we are comforted by the fact that the existing Lerwick Power Station will be maintained on standby mode until at least 2035, a fact that even Ofgem seemed to be unaware of in their consultation documentation.”…”


  36. “Tax haven firms own £7.7bn of UK offshore wind power lines”


    “Transmission cables from the 24 offshore wind farms around the UK — which have a combined value of nearly £7.7bn — are all owned by companies with links to corporate tax havens.

    A Ferret investigation has found that five companies which part-own the cables — HICL Infrastructure, 3i Group, International Public Partnerships Limited, Equitix, and Dalmore Capital — have links to either Luxembourg, Guernsey, Jersey or the Cayman Islands.

    Tax experts called The Ferret’s findings “very significant” and said that the exchequer could be losing “several hundred million pounds” as a result of the tax arrangements. Lost revenue should be “funding the transition out of oil and gas for workers and communities” according to trade unionists and campaigners.

    The firms are part of umbrella groups which won auctions to operate the transmission lines transporting electricity from offshore wind farms to land. These cables are valuable because their owners are paid even if the turbines they connect to are not producing energy.”

    Actually, I think the attempt to make a big deal out of the tax haven links is probably overdone, as it all looks a little tenuous. Still, worth a read, and it reinforces my view that our current electricity generation and distribution system is a shambles. Surely, there can’t even be many Tories left who think that Thatcher’s privatisation of this vital national asset was a good idea, serves us well, or has been well done?


  37. “UK military chief warns of Russian threat to vital undersea cables
    Adm Tony Radakin says any attempt by submarines at damage would be treated as ‘act of war’”


    “The head of the UK’s armed forces has warned that Russian submarine activity is threatening underwater cables that are crucial to communication systems around the world.

    Adm Tony Radakin said undersea cables that transmit internet data are “the world’s real information system”, and added that any attempt to damage them could be considered an “act of war”.

    Speaking to the Times in his first interview since assuming the role, Sir Tony – a former head of the Royal Navy – said there had been a “phenomenal increase in Russian submarine and underwater activity” over the past 20 years.

    He said that meant Moscow could “put at risk and potentially exploit the world’s real information system, which is undersea cables that go all around the world”.

    “That is where predominantly all the world’s information and traffic travels. Russia has grown the capability to put at threat those undersea cables and potentially exploit those undersea cables.”…”.

    He is talking only about communications cables, but one would hope that he and others are also thinking about the risk from being reliant for electricity on underwater cables that are vulnerable to action by bad actors.


  38. “£3.4bn undersea electricity superhighway between Scotland and north England moves forward”


    “The first proposed HVDC link is between Torness, near Edinburgh, and Hawthorn Pit substation in County Durham, and will have 176km of offshore cable. The £1.3bn project will be taken forward by a joint venture between SP Transmission and National Grid Electricity Transmission and is expected to become operational in 2027.

    The other is a £2.1bn link between Peterhead in north east Scotland and Drax in north Yorkshire, to be taken forward by a joint venture between SSEN Transmission and National Grid Electricity Transmission. It will have 440km of subsea cable and is expected to become operational in 2029.

    These two projects are part of National Grid’s project to upgrade the UK’s electricity transmission system and work towards the government’s target of 40GW of offshore wind generation by 2030.

    There are another 14 major projects in development across the network worth a combined £10bn. These include another two 2GW subsea links between Scotland and England, as well as projects in the Humber, Lincolnshire, East Midlands, North of England, Yorkshire, North Kent and four in East Anglia (one being an offshore link between Suffolk and Kent).”


  39. “Steel plate lost at sea during HVDC cable work”


    “AN INVESTIGATION is underway to determine how a steel plate from a hook used in preparatory work for the Shetland interconnector cable was lost at sea.

    The incident happened after damage occurred to one of the grapnel hooks on the MV Sima earlier this week while off the north coast of mainland Scotland.

    A spokesperson for project lead SSEN Transmission said while the steel plate is not considered to present a risk to any marine stakeholders, a notice to mariners was issued…

    …Preparatory work has been been taking place ahead of the HVDC transmission link being laid.

    The boat in question was on a pre-lay grapnel run to remove any debris from the seabed along the cable route….”.


  40. “Lobsters’ deformities linked to subsea cables”


    “Lobsters which hatch near subsea electricity cables risk developing life-limiting deformities, researchers have said.

    Scientists from Heriot-Watt University at St Abbs exposed lobster larvae to electromagnetism in the lab to see how it affected their development.

    They said exposed lobsters were three times more likely to develop abnormalities around the tail and eyes.

    Experts said it meant cables must be buried on the sea bed.

    Many more cables will have to be laid in the coming years to service the huge number of offshore wind farms which will be constructed in Scotland’s waters…

    …The industry body Scottish Renewables said cables were routinely buried in the waters around Scotland’s coast.

    But it can be expensive and makes the cables difficult to maintain.

    Moran Watson, director of policy, said: “Offshore wind developers already bury all cables where possible, often as a condition of their licence, so we welcome this new research as a contribution to those mitigation efforts.

    “It is also important to recognise that offshore renewable energy projects provide one of the most powerful tools we have in the fight against one of most widespread threats to the health of the marine environment – climate change.””

    And two fingers to anyone who cares about ecology. There’s money to be made, and saying that we’re saving the planet while trashing it gives us a free pass.


  41. “Campaigners oppose 112-mile East Anglia power line”


    “A planned 112 mile-long (180km) power line suspended mostly on new pylons across East Anglia should be run under the sea, campaigners said.

    National Grid said the high voltage line, between Norwich, Suffolk and Essex, was needed to carry electricity from offshore wind turbines.

    It said the “essential” line would also be used by the proposed new Sizewell C nuclear power station.

    Essex MP, Sir Bernard Jenkin, said the plan was a “non-starter”.

    The proposed 400kV electricity transmission line, called the East Anglia Green Energy Enablement project, would run between Norwich and a new Bramford substation near Ipswich, and then to Tilbury in south Essex, the Local Democracy Reporting Service said.

    It would use 164ft high (50m) steel pylons, except for where it would run underground through the Dedham Vale area of outstanding natural beauty on the Suffolk/Essex border.”

    I’m not sure which is worse. Saving the planet by trashing it.


  42. “Undersea cable laid to link Shetland to UK energy grid”


    “The first undersea cable is being laid to connect Shetland to the UK mainland’s energy system.

    The Shetland High-Voltage Direct Current (HVDC) link began this week off the coast of Caithness.

    The £660m project will allow Shetland to export renewable electricity to the grid and give the islands security over their electricity supply.

    The project has three separate cable-laying efforts. The 260km seabed link is due to be completed in 2023.”

    Worth repeating – £660m, just for the cables. Never mind the cost of the wind farm, and never mind the ecological damage associated with both.


  43. “More powerful subsea cable proposed for isles”


    “The company said the new proposed cable would be able to accommodate all known onshore and offshore wind projects planned in and around the Western Isles.

    It said it could be in place before 2030.

    Over the years, timescales for the multi-million pound project have slipped from 2015 to 2017 and 2023.

    The project is closely tied to the development of major renewable schemes on the islands.

    Projects that could potentially use the cable include Lewis Windpower’s planned 33-turbine scheme on the Isle of Lewis.

    The project has approval under the UK government’s Contracts for Difference subsidy regime.”

    How much is all this costing? That will be at least the third such cable. And how many millions are there in a “multi-million pound project”?


  44. “Preparations continue for cable to Yell for wind farm export”


    “THE PROCESS of gaining consent for a new subsea electricity cable between Yell and the Shetland mainland to allow wind farms to export power is progressing.

    Scottish Hydro Electric Transmission (SHE Transmission) has now submitted a scoping report to Marine Scotland to determine the type of studies which will need to be taken to support the eventual marine licence application.

    Two wind farms are planned for Yell – the already consented 17-turbine Beaw Field in the south, and the larger Energy Isles in the north west. The latter does not yet have approval from the Scottish Government.

    With the 103-turbine Viking Energy wind farm due to come on stream in 2024, as well as a HVDC interconnector between Shetland and the Scottish mainland, there is a need to install a new, larger 132kV transmission network in the isles.

    This network is needed to connect each wind farm – including the planned 12-turbine Mossy Hill development near Lerwick – to a new substation and HVDC converter station at Kergord, which are currently under construction.

    The two stations form part of the HVDC link project which will allow wind power to be transferred to the national grid – and bring power to Shetland if needs be – through the 260km cable.”

    Not at all “green”, IMO.


  45. In the article, I wrote as follows about the Orkney – Pentland East cable:

    This cable was replaced in late 2020 and the announcement of the completion of the work was welcomed with much publicity from SSE and others. However about 2 months later it was very quietly announced that the new £30 million cable had unexpectedly failed.

    There is as yet no word on whether or not it is to be repaired, as the old one was reconnected, at considerable expense. We can only assume that the cable failure was catastrophic.

    As I understand it, Ofgem have conditionally approved a larger capacity cable to Orkney, with final approval depending on enough wind farm capacity being approved to justify the cable. Perhaps if the larger cable is fully approved, SSE will simply write off the failed cable. Presumably they are hoping that the old, reinstated cable lasts until the larger cable is approved.

    A Freedom of Information request has now provided us with more information. Four questions were asked, and answers were supplied to three, with an exemption claimed in respect of the first one. I set out below the questions and the responses from Ofgem:

    1. What is the nature of the fault in the cable?

    We confirm that we hold this information. However, having considered your request carefully, we consider that this information is exempt from disclosure under section 43(2) of FOIA 2000. Section 43(2) of FOIA provides that information can be withheld where its disclosure would be likely to prejudice the commercial interests of any person, including the relevant suppliers or the public authority holding it, i.e. Ofgem. In the light of this, and having considered whether the public interest in maintaining the exemption is greater than
    the public interest in disclosing the requested information, our decision is to withhold that information

    2. Why, 2 years after the fault emerged, has the cable yet to be repaired?

    In light of expert technical and financial analysis SSEN has determined that a repair would not be sufficient to ensure the ongoing security of electrical supply to Orkney, or be cost effective for customers in the medium to longer term. SSEN has therefore elected to replace the cable entirely. SSEN anticipates the new cable will be installed in summer 2023. In the interim, the original Pentland Firth East cable is in operation.

    3. I understand that Ofgem have given permission to SSEN for expenditure on the cable repair.

    Ofgem has included the ability for SSEN to claim the expenditure for replacing the Pentland Firth East cable in the RIIO-ED2 price control. However, this does not provide guarantee of funding. It allows SSEN to make the case for funding. If Ofgem are satisfied around the needs case, justification and costings, then we can approve the expenditure.

    4. What is the estimated cost of the repair and when will repairs be completed?

    No repair is envisaged, SSEN is replacing the cable. Full costs of replacement are still not known and subject to ongoing commercial negotiation.

    A £30 million cable written off just like that. Who pays?


  46. Jit,

    There is more information. I didn’t want to overload my comment. However, as regards the claimed excuse for not answering question 1, there was a bit more by way of explanation:

    In applying this exemption, we have had to balance the public interest in withholding the
    information against the public interest in disclosure.
    The main factor we considered in deciding where the public interest lay is that because the nature of the fault is subject to an ongoing legal dispute, we do [sic – surely that should read “do not”] consider that it would be in the public interest to compromise the outcome of that ongoing dispute by revealing the nature of the fault because doing so could result in additional costs being passed on to GB energy consumers.

    And yes, there is a right of appeal:

    If you are dissatisfied with the handling of your request, you have the right to ask for an
    internal review. You must contact us for a review no later than 40 working days after the date of this letter. If you require an internal review, please contact us at information.rights@ofgem.gov.uk or by writing to us at 10 South Colonnade, Canary Wharf, London E14 4PU.

    If you are not content with the outcome of the review, you have the right to apply directly to the Information Commissioner for a decision at:
    Information Commissioner’s Office
    Wycliffe House,
    Water Lane,
    SK9 5AF

    Liked by 1 person

  47. “SSEN rules out repair of £30m Pentland Firth East cable after fault”


    A multi-million pound subsea electrical cable – that connected Orkney to the mainland for just a few weeks – appears to have been written off.

    Regulator Ofgem says no repair of the Pentland Firth East link is envisaged, after a fault with the wire cropped up just a couple of months into operation.

    Following a “comprehensive review into the cable failure” in early 2021, Scottish and Southern Electricity Networks (SSEN) Distribution has judged that a repair “may present a risk of future failure”.

    It therefore plans to replace the Pentland Firth East cable, one of the two that link Orkney to the Scottish mainland.

    Designed to ensure resilience of supply to the islands, the £30 million project to replace the wire was completed in November 2020.

    But it wasn’t long before issues with the new link arose, forcing SSEN to reconnect the decommissioned cable…

    It’s only money, after all – our money, in effect, since ultimately we all bear the costs of the “energy transition”.


  48. I have absolutely no idea regarding the validity of these claims, but mention them for what they are worth:

    “Lobster Tales: Offshore Wind Farms Leave Lobster’s With Deformed & Crippled Young”


    Crabs and lobsters are being mesmerised, deformed and crippled by the peculiar electromagnetic fields created by the cables that connect offshore wind turbines.

    A recent scientific study found that the magnetic fields generated by these cables attracts crabs that then remain in place, fixated on the magnetic field, effectively immobilising them.

    Now, another study relating to their cousins, the lobster has shown that the same electromagnetic fields deform their young to the point where they are incapable of ordinary movement ie, they become crustacean cripples.

    For a creature that needs to move over large distances over the seafloor to feed and breed, offshore wind farms may well amount to a death sentence for any lobsters with the misfortune to have these things speared into their natural habitat.

    Not only that, with thousands of these things being plugged into the coastal waters around Britain and along America’s Atlantic Coast, the great offshore wind power push could also spell the death knell for lobster fishers far and wide.


  49. “Seabed power grid to link North Sea wind turbines”


    A vast power grid on the seabed of the central North Sea is being planned as part of a £20bn project to power oil and gas platforms with green electricity.

    Cerulean Winds won the rights to develop projects aimed at reducing the use of gas by offshore installations.

    It aims to link more than 400 offshore turbines with the high voltage cables.

    The company says the plan will involve 10,000 jobs, many of which could be in the supply chain in Scotland.

    It hopes to have the infrastructure in place by 2028.

    There is so much wrong with this. £20Bn for a start. That’s around £700 per UK household. Using “green” (yeah, right) electricity to power oil and gas platforms! 10,000 jobs? “…many of which could…” be in the supply chain in Scotland, but if past form is anything to go by, won’t be. Cables at risk from bad actors. What could possibly go wrong?


  50. By the way, the ever-sensible Douglas Fraser notes some of the problems (though largely not the ones I suggest) during his analysis:

    To become reality, this requires joining up capacity with orders, though some investment is waiting for the orders before capacity can be built. There are concerns that Scotland is not geared up to handle the scale of industrial manufacturing that is now a prospect.

    Those concerns extend to rising prices where the supply chain is unable to meet demand, when steel and wages are among costs also challenging the finances, and when the UK government has set its sights on continued sharp reductions in the cost at which offshore wind can provide for onshore customers.

    This requires a lot of joining up the different elements of this pipeline of huge engineering projects ,from governments and their agencies, the industry and the public to accept big port developments.


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