SONE Newsletter 270 - November 2021

Posted by Wade Allison on 17 November 2021 in Newsletters

Tagged with: Amber Rudd, Arun Khuttan, COP26, EDF, ENTSO-E, Jack Simmons, Paul Spare, Rafael Grossi, Rolls-Royce, SMR, Tom Samson, Trudy Harrison, Urenco, Young Generation Nuclear.

This month

  • Brief report of COP26 for SONE

  • “Who put the lights out?”
    From a report report on the Scottish electricity supply commissioned by Scotland Matters and published by, written by Paul Spare

  • Professor Jack Simmons (1934-2021)

This Newsletter comes rather late because it seemed important to include the report from COP26 kindly contributed by Ian McFarlane who valiantly stayed for the whole meeting. As you will be aware, SONE was not permitted to make a presentation, but, as Ian reports, the younger generation made a good showing and excellent contacts were made.

Paul Spare’s searching paper on the viability of Scotland’s electricity supply follows.

Brief report of COP26 for SONE

Whatever else may emerge from the UN Framework Convention on Climate Change (UNFCC) COP26 conference in Glasgow, held 1-12 November, supporters of nuclear energy will be heartened by the clear signs that ‘new nuclear’ is now at the forefront of urgent moves to limit the likely extent of global warming in the coming decades. The case for new nuclear reactors was heard and welcomed among almost all delegates, as well as those like ourselves (a handful of SONE members) who were, at least, able to attend some of the fringe activities, and also follow the livestreaming of conference discussions. In the conference itself, the Director General of IAEA Rafael Grossi hosted a live-streamed round table discussion on nuclear power in which the importance of new nuclear power was convincingly presented.

YGN activists at COP26 with NetZeroNeedsNuclear banner

Outside the Conference, the urgency for ‘new nuclear’ was conspicuously proclaimed by Young Generation Nuclear (YGN) members clad in their distinctive blue T-shirts. YGN were well organised, and led by Arun Khuttan.

It was Arun himself who hosted the first of three memorable evenings, on 2 November, when the Nuclear Institute provided us with food and drink, and a first opportunity to get to know one another, in the agreeable surroundings of Glasgow University Student Union.

Glasgow YGN Flash Mob can be seen in action here: [Good to watch Ed.]

Secondly on Friday 5 November, as news of UK government approval for development of Rolls-Royce plans for a fleet of SMRs using factory-built PW reactors emerged, a prestige reception in the Marriott Hotel hosted by the New Nuclear Watch Institute included a set of short presentations on industrial plans for small reactors, each one enthusiastically applauded by the 80-100 guests, especially a brief report by Tom Samson, CEO of Rolls-Royce SMR.

Thirdly, on 9 November Urenco and EDF jointly hosted a reception in the city at which Urenco CEO Boris Schucht with IAEA DG Rafael Grossi launched a study of the market for SMRs commissioned by Urenco; the case for new nuclear was then warmly endorsed by Amber Rudd (former member of UK Cabinet) and by Trudy Harrison, MP for the constituency that includes Sellafield.

Between whiles, those us with the opportunity to do so handed out a leaflet specially prepared by SONE addressed to conference delegates, pointing out the direct and indirect benefits of investment in new nuclear plants, especially for use in hydrogen separation (high temperature reactors offer huge energy savings compared with conventional hydrolysis), for desalination and for marine propulsion, among other important indirect benefits. The leaflets were distributed and well-received, especially at the NNWI and Urenco receptions.

“Who put the lights out?”

The challenge of maintaining electricity supply in a Scotland outside the United Kingdom.

From a report commissioned by Scotland Matters and published by

Written by Paul Spare CEng FEI FIMechE


The SNP continue to pursue their vision of an independent Scotland. Although independence could not be achieved for several years, some important issues need to be investigated without delay. Over the centuries, the institutions and systems of England, Scotland and Wales have become deeply intertwined, so that separating them is a substantial challenge and could bring adverse consequences. Nowhere is this more significant than in the supply of electricity.

Since the formation of the high voltage national grid system in the 1920s, the power supply structure in the UK has operated as an integrated whole. Privatisation brought administrative changes, but the operation and control of the grid remained largely unchanged. Operations from Lands End to John O’Groats are controlled from the Wokingham centre. Planning, design and maintenance pays little attention to national boundaries.

Would an independent Scotland be able to establish an equivalent Scottish Grid, independent of England and Wales? Would indep­endence be seriously compromised if the English grid exercised substantial control over such an important commodity as electricity? What costs and financial penalties might be incurred? This article examines the feasibility and implications of a separate Scottish High voltage (HV) power grid.


For a national grid system to be truly independent, it has to be able to provide electricity to its customers with a high level of supply security 365 days per year, without being significantly dependent upon another country. It must be able to provide a high integrity service over a wide range of conditions, from low summer demand to peak winter, and cope with unanticipated demands and ‘loss of supply’ shocks.

Scotland appears to be in a healthy position in that the total capacity of generators connected to the network (12500 MW) is about twice the maximum demand. However, this is to a large an extent an illusion, since the excess is mainly wind turbines that are not controllable, with highly variable outputs that do not match the need for continuous electrical supplies. Many wind turbines have been erected to export power to England at subsidised rates and preferential conditions. The principal generators currently connected in Scotland are: -

  • Hunterston B nuclear power station; 1200 MW

  • Torness nuclear power station;- about 1200 MW

  • Peterhead CCGT 1500 MW

  • Mid-sized hydroelectric plants aggregating to a few hundred MW

  • Pumped storage – Cruachan 440

  • Pumped storage – Foyers 300

  • Biomass 285 MW

  • Landfill gas 109 MW

  • Wind turbines with a nameplate capacity of about 7000 MW.

Since average demand in Scotland is about 3500 MW and the midwinter peak 6000 MW, it can be seen that there is the potential for over supply that could be exported. There are inter-connectors enabling Scotland to export about 5700 MW to England, although the 2250 MW Hunterston DC link is proving unreliable, with long outages. Two questions arise. How would an independent Scottish grid look in 2021, and what would be the situation if independence was granted in say 2025?

Technical and Engineering Aspects

An appreciation of the developing challenge can be gained from the appraisal conducted in the National Grid “Electricity Ten Year Statement” November 2019 ETYS (Ref 1). Section 3.4 summarises the situation in Scotland, with four possible scenarios for future electricity supply, depending on policies and customer behaviour. ETYS noted that….

The rapidly increasing generation capacity, mostly from renewable sources and mainly wind, connecting within Scotland is leading to growing needs in some areas. In three scenarios, inter-connector and storage increases. Across all the scenarios , the fossil fuel generating capacity in Scotland reaches nearly zero.

Investment is required now to handle increased generation. An expanded Scottish wind industry will have no market without new HV grid transmission lines to England. The recently constructed Hunterston DC link was a joint venture between National Grid ESO (Energy System Operator) and SP Networks. It cost over one billion pounds but has proved unreliable. New transmission routes are required. If the England and Wales grid were separated from Scotland, there would be little incentive for National Grid to pay for a further HV link, when supplies could come from generators in England, that would require less expensive network investments. Scottish wind turbines would be stranded assets.

ETYS also noted that………

although gross demand in Scotland is not expected to exceed 6 GW, at times of low renewable output, Scotland may need to import power from England. The present inter-connectors should be sufficient, but a Scottish grid might have to strengthen the South to North equipment.

Apart from the power handling issues, ETYS noted that some associated problems were emerging………

The reduction in synchronous generation could lead to challenges detecting reduced short circuit current levels and with inertia. This potentially leads to increasingly dynamic Scottish network behaviour depending on factors such as weather condition and price of electricity. Conventional synchronous generation (such as Peterhead) must remain in service to ensure secure supplies.

These problems can be managed for the time being because Scotland benefits from the stabilising effect of the generators connected in England. This instability and related problems were considered in an article by David Watson in Engineering and Technology magazine, April 2019 (Ref. 2).

He described the risk of lengthy power cuts after events such as a grid substation failure, lightning or overhead line faults or cyber attack. Black starting the grid following widespread collapse, with the Scottish network being overloaded with uncontrollable renewables, could take up to five days and only then with input from generators in England. It is highly improbable that a stand alone Scottish grid, with the present mixture of power sources would be stable.

The Ofgem investigation into the August 2019 power cut that affected about one million consumers illustrates the developing problem. The loss of 150 MW of distribution after a lightning strike, then two large power stations, Hornsea One wind farm (737MW) and Little Barford (gas-fired 690 MW) caused a plunge in mains frequency and subsequent disconnections. Two of the owners made a voluntary payment of £4.5 million each into Ofgem’s redress fund.

The European Network of Transmission System Operators, ENTSO-E (Ref 3. ) have identified similar risks of frequency abnormalities in Germany and Italy with the increase in wind and solar power. The loss of large synchronous generators has weakened the ability of protection equipment to detect and isolate faults.

The Position in 2025

National Grid envisages an expansion to at least 15000 MW of installed capacity in Scotland in 2025. Hunterston B would have closed. Torness would be required for base load; Peterhead would be retained for a stable synchronised supply. The principal generators would be:-

  • Torness nuclear power station;- about 1200 MW

  • Peterhead CCGT 1500 MW

  • Mid sized hydroelectric plants aggregating to a few hundred MW

  • Pumped storage – Cruachan 440

  • Pumped storage – Foyers 300

  • Biomass 285 MW

  • Landfill gas 109 MW

  • Wind turbines with a nameplate capacity of about 12000 MW are envisaged.

If Scotland had its own National Grid then the figures above show that wind output could be a factor of four greater than the conventional plant. It would be impossible to balance the varying output from the wind sector in certain weather conditions because of the few controllable resources. At the other extreme, providing 6000 MW on a cold winter day with Torness and Peterhead being the only full scale secure supplies, would probably be impossible at times of low wind speed. This problem would be magnified if electric vehicle numbers increase quickly and longer term by the increased electricity demand if gas heating is phased out.

Financial Considerations

The wind power sector is supported by generous subsidies. These are Contracts for Difference (Cfds); Renewable Obligation Certificates (ROCs) and Feed in Tariffs (FiTs). Precise forecasts of the liabilities for a Scottish grid are not possible, but the calculations below indicate the general situation.

In 2020, Scotland produced 35% of UK wind energy, amounting to 23.2 TWh. Total UK on and offshore generation was 65 TWh. The Global Warming Policy foundation (GWPF) have calculated that the UK renewable subsidies in 2019 – 20 (Cfds; ROCs and FiTs) aggregate to about £9 Billion. A pro rata income for Scotland on that basis would be about £3billion in renewable subsidies.

The total cost of ROCs to all UK consumers is 114.7m ROC × £54.43 (the notional value of the ROC) = £6.2 Billion

Considering the ROCs issued to each country, Scotland had 25.2m out of 114.7m issued. The cost to consumers of Scottish ROCs is given by the 25.2m ROCs × £54.43 = £1.37bn.

Some 80% of the Scottish costs are due to wind, on and offshore, which receive about 19.9m ROCs and therefore cost consumers about £1 billion. Scotland’s renewable generators get about 22% of the £6.2 billion….about £1.3 Billion

The interruption of these substantial income streams would be very destructive.

Consider the situation from 2025 described by the National Grid ETYS at which time 15000 MW of generators might connected in Scotland. England may continue to require to import 5000 MW, but might prefer to import continuous, reliable supplies via the European inter-connectors. It may decline the more expensive, variable wind power from Scotland. Such risks need to be addressed well in advance, since the subsidies and income from electricity exports amount to considerable sums.

Investments in the Transmission Network

Consider the north to south flows within Scotland. ETYS includes the following statement related to the boundary B4, which is just north of the Glasgow and Edinburgh latitude. Similar statements are included about future investments for all the Scottish boundaries.

With increasing generation and potential inter-connectors in the Scottish Hydro Electric (SHE) transmission area for all scenarios, the required transfer across boundary B4 is expected to increase significantly over the ETYS period.

Network strengthening will be required from the north coast down to the border before any new renewable power plants can export electricity to the English grid. No firm figures an be given, but costs of many hundreds of millions of pounds must be expected. The Beauly - Denny 400 kV link cost about £1 billion for a capacity of 1200 MW and is 200 km in length.

If Scotland achieved independence, then the electricity market in England would not be obliged to take supplies from Scotland. If Scotland had its own National Grid then the commercial obligations between electricity distributors and the Scottish Generators would be renegotiated. English suppliers would not be under any obligation to take “low carbon” power from Scotland. They would be able to make purchase decisions based on their own commercial interests.

Wind power has been expanded to exploit the generous subsidies available for low carbon sources. The UK legislation compels electricity companies to take wind power in preference to other forms of generation. There is some rationale for constructing power plants hundreds of miles from the customers if they are reliable but not if they are intermittent. Low wind conditions would also provide a challenge if wind farm owners were contracted to supply power to England under a commercial contract. At the time of writing, 6 Sept 2021, wind power is producing less than 1.5% of UK demand. With these conditions, output from generators in Scotland – Torness, Peterhead and the larger hydro plants – would be required for domestic customers. There would be no power available for export to England.

There are also other costs that would have to be managed by an independent Scottish Grid. Balancing Services Use of System (BSUoS) is a service with charges incurred in the first instance by National Grid, with costs that are charged to both generators and suppliers, and ultimately recovered from consumers through higher retail prices. In 2019, this was almost £1.5 billion pounds for the whole of the UK. With the instability risks, any Scottish Grid would need the support of National Grid ESO to maintain the grid 50 Hz supply. The Scottish Grid and the main suppliers in Scotland would almost certainly have to pay for this assistance (costing many of millions of pounds) many months before the expenditure could be recovered from customers.


  • An independent Scottish Grid looks non-viable on the above evidence. Separating Scotland from the stabilising effect of the much larger National Grid would almost certainly weaken the network beyond recovery.

  • Substantial investment will be required from within Scotland on the north to south network in Scotland to enable the electricity from any new wind farms to be fed towards the border with England.

  • Closing conventional power stations such as Peterhead and Torness, whilst increasing the number of wind turbines will risk serious instability and lengthy power cuts. At times of low wind, all generation would be require to meet domestic needs, leaving none for export.

  • If Scotland gained independence, there would be no obligation for suppliers in England to buy renewable power under the ROC or related schemes.

  • In addition, National Grid’s commercial strength would enable it to dominate any contractual negotiations with Scotland because of the unpredictable nature of the wind power it had to sell.

  • If separated from the UK National Grid, an equivalent government subsidy system would have to be established from Scottish consumers. Since there is a disproportionate concentration of wind farms in Scotland, the cost per capita to households could be three times that levied across the UK


  1. National Grid 1 ETYS November 2019

  2. Watson D, Engineering and Technology Magazine April 2019

  3. Dispersed Generation Impact on CE Region Security, European Network of Transmission System Operators for Electricity 11 December 2014.

[The viability of the entire UK Grid this winter looks questionable, too. SONE members should wrap up warm and buy some yule logs, perhaps. Ed.]

Professor Jack Simmons (1934-2021)

It is with the greatest sadness that we report the death of Jack Simmons. A member of the Committee for many years, Jack contributed much academic wisdom, always with his characteristic smile. In 1999 he published an important book Radiation Protection Dosimetry, A Radical Reappraisal. In it he exposed the professional make-believe account that lies behind the extreme precaution restricting the use of ionising radiation today. As he wrote in the Introduction …re-thinking is essential when inconsistencies between theory and experiment become too glaring to be ignored. He went on to compare current dogma in radiation biology with the constructs of Ptolemaic Astronomy that were swept away by the Copernican Revolution. Posterity will benefit from his work as one of those who made the case that the benefits of nuclear energy and its radiation should be enjoyed by mankind without fear, even with a smile.

Wade Allison, Hon. Sec.
17 November 2021