A Brief History Of Scottish Hydropower
The title of this post, is the same as that of this page on the Drax Group web site.
This is the introductory paragraph.
Over the last century, Scottish hydro power has played a major part in the country’s energy make up. While today it might trail behind wind, solar and biomass as a source of renewable electricity in Great Britain, it played a vital role in connecting vast swathes of rural Scotland to the power grid – some of which had no electricity as late as the 1960s. And all by making use of two plentiful Scottish resources: water and mountains.
These are some points from the page.
- The first scheme was built in the last years of the nineteenth century and provided power for aluminium smelting.
- The first modern scheme was the Lanark Hydro Electric Scheme, which was built in the 1920s and is still running today, under the ownership of Drax Group.
- In 1935, the Galloway scheme, set the tone for later projects with architecture including stylised dams and modernist turbine halls.
- The North of Scotland Hydroelectric Board was founded in 1943.
- Sloy, the largest conventional hydro-electric station opened in 1950 and has a capacity of 152.5 MW.
- Building the dams and power stations appears to have been hard but well-paid work.
- By the mid Sixties, the North of Scotland Hydroelectric Board had built 54 main power stations and 78 dams. Northern Scotland was now 90% connected to the national grid.
- In 1965, the world’s then largest reversible pumped storage power station opened at Cruachan.
- In 2009, the last major scheme at Glendoe opened.
The schemes are a working catalogue of everything you can do with water to generate and store electricity.
Future development now seems to be moving in two directions.
The Drax page says this about new hydro-electric schemes.
In recent years, however, the real growth has been in smaller hydro-electric schemes that may power just one or a handful of properties – with more than 100 MW of such generation capacity installed in the Highlands since 2006.
On the other hand, several large pumped storage schemes are under development.
- Balliemeanoch – 1.5 GW/45 GWh
- Coire Glas – 1.5 GW/30 GWh
- Corrievarkie – 600 MW/14.5 GWh
- Red John – 450 MW/2.8 GWh
Note.
These schemes add up to an output of just over 4 GW and a colossal 92.3 GWh of storage.
The existing Foyers scheme and the under-development Coire Glas and Red John schemes. all use Loch Ness as the lower reservoir.
Two of these under-development schemes will be larger than the current largest pumped storage system in the world; Bath County Pumped Storage Station in Virginia in the United States, which is a 3 GW/24 GWh system.
Conclusion
Adding large numbers of wind turbines and tens of GWs to Scotland’s existing pumped storage could transform not just Scotland’s but most of Western Europe’s green energy production.
Glendoe Hydro Power Station
When I think of hydro-electric power stations in the UK, I generally, think that most of the hydro-electric power stations were built years ago by organisations like the North of Scotland Hydroelectric Board. These power stations were one of the staples of the Meccano Magazine, of which I was a long-term subscriber in the 1950s.
But Glendoe hydro-electric power station is relatively new having been opened in 2009. At only 100 MW, the power-station may not be large in comparison to others around the world, but it does show what can be built in the Highlands of Scotland.
This Google Map shows the layout of the power station.
Note.
- The red arrow indicates the location of Glencoe power station, which is underground.
- To the North of the power station, is the Southern end of Loch Ness.
- In the South-Eastern corner of the map there is the lake from which the power station draws its water.
- The dam is at the Western end of the lake.
According to this article on Power Technology, the project cost £160 million.
This extract from a page on the SSE Renewables web site, describes the layout of the tunnels and the operation of the power station.
Engineers began planning the Glendoe project as far back as October 2001. Formal construction work at the site started over four years later, in January 2006. It involved constructing a 960 metre-wide dam on the River Tarff to create a new reservoir some 600 metres above the power station, giving it the greatest head of any hydro electric power station in the UK.
An 8.6 kilometre tunnel connects the reservoir to the power station that is built 250 metres below ground level, about two kilometres from the banks of Loch Ness. Although some of the tunnel was created using traditional drill and blast techniques that would have been familiar to the Tunnel Tigers of the last century, much of its length was bored out using a massive tunnelling machine named Eliza Jane by local schoolchildren.
The SSE page also describes the working and living conditions of those who built the scheme.
Most lived in specially constructed camps high in the hills above Loch Ness, braving brutal weather conditions in winter, and the fearsome Scottish midges in the summer.
The SSE page also gives the main use of the power station.
Today, the main operating feature of Glendoe is its ability to react quickly to changing demand for electricity, being able to reach full output in just 90 seconds.
So when there is an important football or rugby match on the television, it is ideal to supply the surge of electricity, when everybody puts on the kettle at half time.
Could This Power Station Have A Pumped Storage System Added?
Consider.
- There is a large lake six hundred metres above the power station.
- Loch Ness is a large source of water at the bottom of the mountain.
- Every tonne or cubic metre of water pumped into the upper lake would store 1.63 kWh of electricity.
- The world’s and the UK’s tunneling engineers are getting better and more ambitious.
- When this power station was built in the early years of this century, there wasn’t the large amount of wind turbines in Scotland, that there are now.
I suspect, it’s an idea that’s been looked at, but the costs or the distance to pump the water might kill it.
If a second project was the same size as the first, it would cost £210 million based on inflation.
But.
- It wouldn’t need another dam or a substation to connect to the National Grid.
- There would probably be a need for extra excavation at the power station to put in the pumps.
- I suspect it would need an extra tunnel to get the water uphill.
- One tunneling engineer told me, as with sex, digging a second tunnel is easier.
The main benefit, would be that it would be hidden infrastructure.
As to the energy storage capacity, I estimate from maps that the top reservoir at Glendoe is about half the size of Loch Mohr at Foyers power station, but the head is 600 metres as against 197 metres. As Foyers can store 10 GWh, it looks to me, that Glendoe could store around 15 GWh.
Also, as Glendoe power station was designed and built after the successful conversion of Foyers to a pumped storage station, I wouldn’t be surprised to find that Glendoe was designed, so that the station could be converted to pumped storage at a later date.
Conclusion
This scheme will be seriously looked at for extension with a pumped storage facility.
Corrievarkie Pumped Storage Hydro Project
When I wrote ILI Group To Develop 1.5GW Pumped Storage Hydro Project, I noticed that they were also developing a scheme called Corrievarkie at Loch Ericht.
This document on the Highland Council web site gives details of the planning application.
This is said.
Corrievarkie Pumped Storage Hydro Scheme – Construction and Operation of a Pumped Storage Hydro Scheme with generation capacity of approximately 600MW and storage capacity of 14.5 GWh comprising headpond reservoir, surge shaft, tailpond, headrace, tailrace, power cavern, temporary access tracks for construction, permanent access tracks, 12 construction compounds, temporary worked accommodation, switching station, loch based structures and ancillary infrastructure.
Note.
- With storage of 14.5 GWh, it is bigger than Electric Mountain, which has only 9.1 GWh of storage.
- But with a generation capacity of 600 MW, this is only a third of that of Electric Mountain.
This Google Map shows the area, where the scheme will be realised.
The red arrow indicates Corrievarkie Lodge.
I shall be interested to see the full details of this scheme.
Red John Pumped Storage Hydro Project
When I wrote ILI Group To Develop 1.5GW Pumped Storage Hydro Project, I noticed that they were also developing a scheme called Red John near Inverness.
The title of this post is the same as that of this article on Power Technology.
I have also found a web site for the project, which is part of the ILI Group web site.
- The scheme has an output of 450 MW.
- The storage capacity is 2,800 MWh or 2.8 GWh.
- The scheme has planning consent.
- The project is budgeted to cost £550 million.
- The construction program indicates that the scheme will be completed by the end of 2025.
This paragraph from this article on Water Power and Dam Construction, describes the head and tail ponds.
The Red John project will be located on the eastern shore of the north end of Loch Ness in the Highlands of Scotland. Loch Ness is to be the tail pond for the project, with the head pond to be newly constructed. It will use the natural topography between Loch Duntelchaig, Loch Ashie and Loch na Curra and Lochan an Eoin Ruadha, from where the development gets its Red John name.
This Google Map shows the area.
Note.
- Loch Ness is in the West.
- Loch Ashie is in the North.
- Loch Duntelchaig is in the East.
This second Google Map shows the area between Lochs Ness, Duntelchaig and Ashie in more detail.
Loch na Curra and Lochan an Eoin Ruadha are now named and can be picked out in the previous map.
It looks like there will be a lot of heavy construction works to create the head pond.
Conclusion
This scheme has the output of a large gas-fired power station for just over six hours.
The finances must add up, as no-one would back a scheme like this if they didn’t get an adequate return on their money.
ILI Group To Develop 1.5GW Pumped Storage Hydro Project
The title of this post, is the same as that of this article on Solar Power Portal.
These are the first two paragraphs.
Clean energy developer ILI Group has begun the initial planning phase for a new pumped storage hydro project in Scotland.
The Balliemeanoch project at Loch Awe, Dalmally in Argyll and Bute will be able to supply 1.5GW of power for up to 30 hours. It is the third and largest of ILI’s pumped storage hydro projects, with the other two being Red John at Loch Ness and Corrievarkie at Loch Ericht.
It is a big scheme at 45 GWh.
The ILI Group has an extensive web site, that is worth a read.
- This page describes pumped storage.
- This long document from the company is part of their submission to the Government.
The company seems to be going in the right direction.
This Google Map shows the Loch Awe area.
Note.
- Loch Awe is in the North West corner of the map.
- Loch Fyne is the large loch in the South East corner of the map.
- Balliemeanoch is marked by the red arrow.
I am a bit puzzled as to the layout of the scheme.
But I have now noticed a Ballimeanoch close by Loch Awe.
This is a map of its location.
I suspect that is the correct location of the pumped storage scheme.
I shall be interested to see the layout of the full scheme.
SSE Renewables Launches 1.5GW Coire Glas Construction Tender
The title of this post, is the same as that of this article on renews.biz.
These are the first two paragraphs.
Hydro construction companies have been invited to submit tenders for construction of SSE Renewables’ proposed 1500MW pumped hydro storage scheme at Coire Glas, in Scotland.
Coire Glas, on the shores of Loch Lochy near Invergarry, would be the first large-scale pumped hydro storage scheme to be built in the United Kingdom for more than 30 years.
There appears to be global interest and six shortlisted bidders.
- The ANDRITZ HYDRO and Voith Hydro partnership
- The Bechtel, Acciona Construcción and Webuild S.p.A consortium
- The BAM Nuttall, Eiffage Génie Civil and Marti Tunnel consortium
- The Dragados and BeMo Tunnelling UK consortium
- GE Hydro France
- STRABAG UK
Bidders like these probably wouldn’t bother to get involved unless they knew that funding of the project was in place and it was pretty certain that the project will be constructed.
In World’s Largest Wind Farm Attracts Huge Backing From Insurance Giant, I talk about how Aviva are funding the Hornsea wind farm.
I believe, that insurance and pension companies like abrdn, Aviva and L & G could find a way of financing a scheme like Coire Glas.
Conclusion
It looks to me, that it’s almost certain that Scotland will get a 1.5GW/30 GWh pumped-storage system at Coire Glas.
Coire Glas could supply slightly more power than Sizewell B nuclear power station for twenty hours.
Now that’s what I call backup!
Power Storage Is The Next Big Net Zero Challenge
The title of this post, is the same as that of this Opinion from Bloomberg.
This is the sub-heading.
Britain’s pioneering plans for renewable energy show the global need could be massive. The means don’t yet exist.
The opinion is very much a well-written must-read.
One new project the article mentions is a 30 GWh pumped storage project at Coire Glas in the Scottish Highlands, that is planned by SSE.
I discuss this scheme in The Coire Glas Pumped Storage Scheme.
Bloomberg didn’t say it, but this pumped storage scheme could give the UK energy security.
Drax’s Plans For Cruachan
Cruachan Power Station is a pumped-storage hydroelectric power station in Argyll and Bute, Scotland.
- It can generate 440 MW of power.
- It has a storage capacity of 7.1 GWh.
- The power station is owned by Drax.
This Google Map shows the area around the power station.
Note.
- Cruachan Reservoir is the upper reservoir for the power station.
- The River Awe is the lower reservoir.
- The turbines for the power station are in a hollowed-out Ben Cruachan.
- There is a visitor centre, which is two-hundred metres from the Falls of Cruachan station, that can be seen on the map, by the river.
More information on visiting can be found at the Visit Cruachan web site.
This second map shows the Southern part of the Cruachan Reservoir to a larger scale.
Note the strength of the dam.
The Operation Of Cruachan Power Station
Wikipedia says this about the operation of Cruachan power station.
The station is capable of generating 440 megawatts (590,000 hp) of electricity from four turbines, two of 100 megawatts (130,000 hp) and two of 120 megawatts (160,000 hp) capacity, after two units were upgraded in 2005. It can go from standby to full production in two minutes, or thirty seconds if compressed air is used to start the turbines spinning. When the top reservoir is full, Cruachan can operate for 22 hours before the supply of water is exhausted. At full power, the turbines can pump at 167 cubic metres (5,900 cu ft) per second and generate at 200 cubic metres (7,100 cu ft) per second.
What I find surprising, is that they only upgraded two turbines to 120 MW. I would suspect that there was some other factor that stopped all turbines from being upgraded.
So I would be very surprised if Drax upgraded the power of the existing station.
The Wikipedia extract claims that the Cruachan power station can provide power for 22 hours, if the reservoir, which has a capacity of 7.1 GWh is full. A simple calculation gives an average output in 323 MW. Does that indicate an efficiency of 73.4 %, by dividing 323 by 440.
But no pumped storage system of the 1950s is 100 % efficient. The Ffestiniog Power Station, which opened two years before Cruachan has an efficiency of 73 %. , which appears to be in line with the figures for Cruachan.
Cruachan Power Station And Nuclear Power
Wikipedia says this about Cruachan power station and Hunterston A nuclear power station.
Construction began in 1959 to coincide with the Hunterston A nuclear power station in Ayrshire. Cruachan uses cheap off-peak electricity generated at night to pump water to the higher reservoir, which can then be released during the day to provide power as necessary.
Note.
- Hunterston A power station closed in 1990.
- Hunterston B power station closed a few days ago.
- Scotland now only has one nuclear station at Torness.
It looks like the method of operation will have to change.
Cruachan Power Station And Wind Power
The obvious replacement source of energy at night to replace the nuclear power is wind power.
As I write this the UK is generating 8.5 GW of power from wind turbines.
Surely, enough can be diverted to Cruachan to fill the Cruachan Reservoir.
Cruachan 2
Drax’s plans for Cruachan are based around the building of a second underground power station, which is not surprisingly called Cruachan 2. This page on the Drax web site describes Cruachan 2.
- It will be a 600 MW power station.
- It will be to the East of the current power station.
- More than a million tonnes of rock would be excavated to build the power station.
The existing upper reservoir, which can hold 2.4 billion gallons of water, has the capacity to serve both power stations.
I think it is reasonable to assume the following about Cruachan 2.
- Design of the turbines will have improved in the sixty years since the Francis turbines for the original power station were ordered and designed.
- The turbines will now be precisely computer-controlled to optimise the operation of the power station.
- The turbines will have a faster response, than even that of Cruachan 1, which will help to match output to demand.
But most importantly, I suspect that the efficiency will be higher due to improved turbine design.
I can do a simple calculation, where I will assume the following figures for the two power stations.
- Cruachan 1 – 440 MW – Efficiency – 73 % – Full Power – 323 MW
- Cruachan 2 – 600 MW – Efficiency – 80 % – Full Power – 480 MW
It looks to me that 1040 MW can be used to store water in the reservoir and at this rate it would take 6.8 hours to fill the reservoir. With just Cruachan 1 in operation, filling the reservoir would take sixteen hours.
It looks like with moderate winds generating sensible amounts of electricity, it should be possible to fill the reservoir overnight using both Cruachan 1 and Cruachan 2.
When running flat-out, the combined station can generate 803 MW. At that rate it will generate the power for just under nine hours.
The Wikipedia entry for Francis turbines says this.
Francis turbines are the most common water turbine in use today, and can achieve over 95% efficiency.
Applying 95 % Efficiency to Cruachan 2 would give the following.
- An output of 570 MW for Cruachan 2.
- A total output of 1010 MW for the combined station.
- This would mean the combined station could deliver 1.01 GW for just over seven hours.
Modern control technology would probably be used to ensure that the output of the combined Cruachan station filled in the gaps between demand and supply.
Could The Size Of Cruachan Reservoir Be Increased?
This would increase the amount of energy stored.
I suspect that it probably can’t be increased, as any increases would have been done by now.
Conclusion
It looks like very good engineering to me.
- There is a good chance, that on most nights, the reservoir will be filled using wind energy
- The maximum output of the Cruachan power station has been more than tripled from 323 to 1010 MW.
- There has been no increase in the size of the Cruachan reservoir.
Scotland will now have a GW-sized hydro-electric power station.
Future Offshore Wind Power Capacity In The UK
I am building this table, so that I can get a feel for the electricity needs of the UK.
According to Wikipedia, on February 2020, there were thirty six offshore wind farms consisting of 2180 turbines with a combined capacity of 8113 megawatts or 8.113 gigawatts.
Currently, these offshore wind farms are under construction, proposed or are in an exploratory phase.
- Triton Knoll – 857 MW – 2021 – Under Construction
- Hornsea Two – 1386 MW – 2022 – Under Construction
- Moray East – 960 MW – 2022 – Under Construction
- Neart Na Gaoithe – 450 MW – 2023 – Under Construction
- Seagreen Phase 1 – 1075 MW – 2023 – Under Construction
- Dogger Bank A – 1200 MW – 2023/24 – Proposed
- Dogger Bank B – 1200 MW – 2024/25 – Proposed
- Dogger Bank C – 1200 MW – 2024/25 – Proposed
- Moray West – 1200 MW – 2024/25 – Exploratory
- Hornsea Three – 2400 MW – 2025 – Proposed
- East Anglia One North 800 MW – 2026 – Exploratory
- East Anglia Two – 900 MW – 2026 – Exploratory
- East Anglia Three – 1400 MW – 2026 – Exploratory
- Sofia Offshore Wind Farm Phase 1 – 1400 MW – 2023/2026 – Under Construction
- Hornsea Four – 1000 MW (?) – 2027 – Exploratory
- Rampion Two Extension – 1200 MW – Exploratory
- Norfolk Vanguard – 1800 MW – Exploratory
- Norfolk Boreas – 1800 MW – Exploratory
Note.
- The date is the possible final commissioning date.
- I have no commissioning dates for the last three wind farms.
- Wikipedia says that the Hornsea Four capacity is unknown by Ørsted due to the ever increasing size of available wind turbines for the project.
I can total up these wind farms by commissioning date.
- 2021 – 857 MW
- 2022 – 2346 MW
- 2023 – 1525 MW
- 2024 – 1200 MW
- 2025 – 6000 MW
- 2026 – 4500 MW
- Others – 5800 MW
I can draw these conclusions.
- Total wind farm capacity commissioned each year is increasing.
- It looks like there will be a capacity to install up to 5000 or 6000 MW every year from about 2025.
- If we add my figures for 2021-2026 to the 8113 MW currently installed we get 24541 MW.
- Adding in 6000 MW for each of the four years from 2027-2030 gives a total of 48541 MW or 48.5 GW.
As I write this on a Sunday afternoon, wind power (onshore and offshore) is supplying 13 GW or forty-four percent of our electricity needs.
I have further thoughts.
Parallels With North Sea Oil And Gas
I was very much involved in the development of North Sea oil and gas, as my software was used on a large number of the projects. I had many discussions with those managing these projects and what was crucial in shortening project times was the increasing availability of bigger rigs, platforms and equipment.
Big certainly was better.
I believe that as we get more experienced, we’ll see bigger and better equipment speeding the building of offshore wind farms.
Reuse of Redundant North Sea Oil And Gas Platforms
Don’t underestimate the ability of engineers to repurpose redundant oil and gas platforms for use with windfarms.
Electrolysers on the platforms can convert the electricity into hydrogen and use redundant gas pipes to bring it ashore.
Some processes like steelmaking could use a lot of hydrogen.
Platforms can be used as sub-stations to collect electricity from windfarms and distribute it to the various countries around the North Sea.
Hydrogen
Some processes like steelmaking could use a lot of hydrogen. And I don’t think steelmakers would be happy, if the supply was intermittent.
So why not produce it with giant electrolysers on redundant oil and gas platforms and store it in redundant gas fields under the sea?
A large store of hydrogen under the sea could have the following uses.
- Steelmaking.
- Feedstock for chemical manufacture.
- Transport
- Power generation in a gas-fired power station, that can run on hydrogen.
It would just need a large enough hydrogen store.
Energy Storage
This large amount of wind power will need a large amount of energy storage to cover for when the wind doesn’t blow.
Some of this storage may even be provided by using hydrogen, as I indicated previously.
But ideas for energy storage are coming thick and fast.
The North Sea Link To Norway
The North Sea Link is much more important than an interconnector between Blyth in Northumberland and Norway.
- At the Norwegian end the link is connected to a vast pumped storage energy system in the mountains of Norway.
- This pumped storage system is filled in two ways; Norwegian rain and snow and UK wind power through the interconnector.
- In times of need, we can draw electricity through the interconnector from Norway.
- It has a capacity of 1.4 GW.
- It was delivered on time for a cost of around €2 billion.
It can almost be thought of as an international bank of electricity and is probably one of the most significant pieces of European infrastructure built in recent years.
There are also plans to build NorthConnect, that would connect Peterhead in Scotland to Norway.
Conclusion
It looks like we’ll be able to reap the wind. And possibly 50 GW of it!
Sun Cable’s Australia-Asia PowerLink
Two weeks ago, in How Clean Energy And Jobs Can Flow From Morocco to The UK, I talked about a plan to generate electricity using solar arrays in Southern Morocco and use an underwater interconnector to bring it to the UK.
If you think that project was ambitious and distinctly bonkers, then that project is outshone by Sun Cable‘s Australia-Asia PowerLink, which is shown in this SunCable graphic.
These are a few facts about the project.
- Electricity will be generated by solar panels in the Northern Territories of Australia.
- There will be 12,000 hectares of solar panels in Australia, which will create 3.2 GW of electricity for distribution.
- There will be a 36-42 GWh battery in Australia.
- There will be 4,200 km of submarine HVDC cable to deliver the electricity to Singapore and Indonesia.
- It looks like there will be batteries in Darwin and Singapore.
- The link could supply up to fifteen percent of Singapore’s electricity.
It is certainly an ambitious project, that will contain the world’s largest solar array, the world’s largest battery, and the world’s longest submarine power cable.
Note.
- Currently, the largest solar park in the world is Bhadia Solar Park in India, which is half the size of the solar array proposed.
- At 720 km, the North Sea Link is the largest undersea HVDC is operation.
- The largest battery in the UK is Electric Mountain in Snowdonia, which is only 9.1 GWh.
- A Tesla Megapack battery of the required size would probably cost at least ten billion dollars.
This is certainly, a project that is dealing in superlatives.
Is The Australia-Asia PowerLink Possible?
I shall look at the various elements.
The Solar Panels
I have flown a Piper Arrow from Adelaide to Cairns.
- My route was via Coober Pedy, Yulara, Alice Springs and Mount Isa.
- There didn’t seem to be much evidence of rain.
- The circle from South to East took four days of almost continuous flying, as Australia is not a small country.
- It left me with the impression of a flat featureless and hot country.
Having seen solar panels on flat areas in the UK, the Australian Outback could be ideal for solar farms.
Sun Cable are talking about 10,000 hectares of solar panels, which is roughly 38.6 square miles or a 6.2 mile square.
Given enough money to source the solar panels and install them, I would expect that the required solar farm could be realised.
The Cable
Consider.
- The North Sea Link is a 1.4 GW cable that is 720 km. long.
- I would size it as 10008 GW-km, by multiplying the units together.
- The Australia-Asia PowerLink will be 4200 km or nearly six times as long.
- But at 3.2 GW as opposed to 1.4 GW, it will have 2.3 times the capacity.
- I would size it as 13,400 GW-km.
Whichever way you look at it, the amount of cable needed will be massive.
The Battery
Currently, the largest battery in the world is the Bath County Pumped Storage Station, which has these characteristics.
- Peak power of 3 GW
- Storage capacity of 24 GWh.
Sun Cable’s 36-42 GWh battery will be the largest in the world, by a long way.
But I don’t think pumped storage will be suitable in the usually dry climate of Northern Australia.
The largest lithium-ion battery in the world is the Hornsdale Power Reserve in South Australia, which is only 150 MW/194 MWh, so something else will have to be used.
As Highview Power are building a CRYOBattery for the Atacama region in Chile, which I wrote about in The Power Of Solar With A Large Battery, I wonder, if a cluster of these could provide sufficient storage.
The Anonymous Widower 