59-527: The Cruachan Power Station (also known as the Cruachan Dam ) is a pumped-storage hydroelectric power station in Argyll and Bute , Scotland, UK. The scheme can provide 440 MW of power and produced 705 GWh in 2009. The turbine hall is located inside Ben Cruachan , and the scheme moves water between Cruachan Reservoir and Loch Awe , a height difference of 396 m (1,299 ft). It
118-447: A "clean" appearance, so the operational equipment is housed within the dam wall. The penstocks are a pair of tunnels, 260 m (850 ft) long and inclined at 56° from the horizontal with a 5.3 m (17 ft) diameter, which then bifurcate into four steel lined 190 m (620 ft) long, 2.5 m (8 ft 2 in) diameter shafts. The penstocks underwent a major inspection and refurbishment in 2003. The power station
177-607: A cost-effective solution for a water reservoir in a micro-pumped hydro energy storage. Such plants provide distributed energy storage and distributed flexible electricity production and can contribute to the decentralized integration of intermittent renewable energy technologies, such as wind power and solar power . Reservoirs that can be used for small pumped-storage hydropower plants could include natural or artificial lakes, reservoirs within other structures such as irrigation, or unused portions of mines or underground military installations. In Switzerland one study suggested that
236-436: A four-week test of a pumped storage underwater reservoir. In this configuration, a hollow sphere submerged and anchored at great depth acts as the lower reservoir, while the upper reservoir is the enclosing body of water. Electricity is created when water is let in via a reversible turbine integrated into the sphere. During off-peak hours, the turbine changes direction and pumps the water out again, using "surplus" electricity from
295-470: A hard granite intrusion . Construction of the power station required the removal of 220,000 cubic metres (7,800,000 cu ft) of rock. Access to the hall is gained by a road tunnel 1 km (0.62 miles) long, 4 m (13 ft) high and 7 m (23 ft) wide, which is warm and humid enough to allow tropical plants to grow. The transformers step up the voltage from 16 kV to 275 kV for transmission. Six oil-filled cables carry
354-486: A hybrid system that both generates power from water naturally flowing into the reservoir as well as storing water pumped back to the reservoir from below the dam. The Grand Coulee Dam in the United States was expanded with a pump-back system in 1973. Existing dams may be repowered with reversing turbines thereby extending the length of time the plant can operate at capacity. Optionally a pump back powerhouse such as
413-510: A network of 19 km (12 miles) of tunnels. Around 10% of the energy from the station is generated from rainwater; the rest is from the water pumped up from Loch Awe. 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 30 seconds if compressed air
472-404: A pump and as a turbine generator (usually Francis turbine designs). Variable speed operation further optimizes the round trip efficiency in pumped hydro storage plants. In micro-PSH applications, a group of pumps and Pump As Turbine (PAT) could be implemented respectively for pumping and generating phases. The same pump could be used in both modes by changing rotational direction and speed:
531-591: A reservoir. The largest one, Saurdal, which is part of the Ulla-Førre complex, has four 160 MW Francis turbines , but only two are reversible. The lower reservoir is at a higher elevation than the station itself, and thus the water pumped up can only be used once before it has to flow to the next station, Kvilldal, further down the tunnel system. And in addition to the lower reservoir, it will receive water that can be pumped up from 23 river/stream and small reservoir intakes. Some of which will have already gone through
590-473: A significant amount of energy is by having a large body of water located relatively near, but as high as possible above, a second body of water. In some places this occurs naturally, in others one or both bodies of water were man-made. Projects in which both reservoirs are artificial and in which no natural inflows are involved with either reservoir are referred to as "closed loop" systems. These systems may be economical because they flatten out load variations on
649-641: A similar role in the electrical grid as pumped storage if appropriately equipped. Taking into account conversion losses and evaporation losses from the exposed water surface, energy recovery of 70–80% or more can be achieved. This technique is currently the most cost-effective means of storing large amounts of electrical energy, but capital costs and the necessity of appropriate geography are critical decision factors in selecting pumped-storage plant sites. The relatively low energy density of pumped storage systems requires either large flows and/or large differences in height between reservoirs. The only way to store
SECTION 10
#1732773406827708-437: A smaller power station on its way. In 2010, the United States had 21.5 GW of pumped storage generating capacity (20.6% of world capacity). PSH contributed 21,073 GWh of energy in 2020 in the United States, but −5,321 GWh (net) because more energy is consumed in pumping than is generated. Nameplate pumped storage capacity had grown to 21.6 GW by 2014, with pumped storage comprising 97% of grid-scale energy storage in
767-409: A three-section 48 ft × 12 ft (14.6 m × 3.7 m) modernist mural in wood, plastic and gold leaf by English artist Elizabeth Falconer . The mural includes Celtic crosses , pylons, mythical beasts, and men of industry. The first section depicts the mythical Cailleach Bheur , who guarded the spring underneath the mountain. The middle panel commemorates 15 workers killed when
826-529: A total installed capacity of 1344 MW and an average annual production of 2247 GWh. The pumped storage hydropower in Norway is built a bit differently from the rest of the world. They are designed for seasonal pumping. Most of them can also not cycle the water endlessly, but only pump and reuse once. The reason for this is the design of the tunnels and the elevation of lower and upper reservoirs. Some, like Nygard power station, pump water from several river intakes up to
885-518: A total installed storage capacity of over 1.6 TWh . A pumped-storage hydroelectricity generally consists of two water reservoirs at different heights, connected with each other. At times of low electrical demand, excess generation capacity is used to pump water into the upper reservoir. When there is higher demand, water is released back into the lower reservoir through a turbine , generating electricity. Pumped storage plants usually use reversible turbine/generator assemblies, which can act both as
944-404: Is 7 m (23 ft) in diameter and 935 m (3,068 ft) long. The Cruachan Reservoir is 396 m (1,299 ft) above Loch Awe, and is contained by a dam 316 m (1,037 ft) long. The reservoir has a catchment area of 23 km (8.9 sq mi), and is capable of holding 7 gigawatt-hours (25 TJ) of energy. Environmental restrictions meant that the dam had to have
1003-531: Is also used to cope with sudden surges in the demand for electricity, such as at the end of popular television programmes . Despite the use of some rainwater, Cruachan is not a net generator of electricity: it uses more energy for pumping water and spinning its turbines than it generates. Water is pumped from Loch Awe to the upper reservoir, 396 m (1,299 ft) above, during periods of low energy use (most often at night), and then released when needed. The upper reservoir also receives rainwater, supplemented by
1062-441: Is much smaller than the land occupied by the solar and windfarms that the storage might support. Closed loop (off-river) pumped hydro storage has the smallest carbon emissions per unit of storage of all candidates for large-scale energy storage. Pumped storage plants can operate with seawater, although there are additional challenges compared to using fresh water, such as saltwater corrosion and barnacle growth. Inaugurated in 1966,
1121-544: Is necessary. Smaller pumped storage plants cannot achieve the same economies of scale as larger ones, but some do exist, including a recent 13 MW project in Germany. Shell Energy has proposed a 5 MW project in Washington State. Some have proposed small pumped storage plants in buildings, although these are not yet economical. Also, it is difficult to fit large reservoirs into the urban landscape (and
1180-476: Is now done using a remotely operated underwater vehicle . To commemorate the 50th anniversary of the station's opening, a 2015 BBC radio documentary Inside the Rock described its construction. The Cruachan station temporarily stores energy at times of low demand, and releases it at times of high demand, when electricity prices are higher, reducing the maximum power that must be provided by other power stations. It
1239-672: Is one of only four pumped storage power stations in the United Kingdom, and is capable of providing a black start capability to the National Grid . Construction began in 1959 to coincide with the Hunterston A nuclear power station in Ayrshire. Cruachan uses cheap electricity generated at night to pump water to the higher reservoir, which can then be released during the day to provide power as necessary. The power station
SECTION 20
#17327734068271298-511: Is open to visitors, and around 50,000 tourists visit it each year. The power station is on the A85 road , about 8 km (5.0 miles) west of Dalmally , on a branch of Loch Awe leading to the River Awe , which is the outflow from the loch, at its north west corner. There is a seasonally open Falls of Cruachan railway station nearby. Construction commenced in 1959, and the power station
1357-640: Is rarely due to wind or solar power alone, increased use of such generation will increase the likelihood of those occurrences. It is particularly likely that pumped storage will become especially important as a balance for very large-scale photovoltaic and wind generation. Increased long-distance transmission capacity combined with significant amounts of energy storage will be a crucial part of regulating any large-scale deployment of intermittent renewable power sources. The high non-firm renewable electricity penetration in some regions supplies 40% of annual output, but 60% may be reached before additional storage
1416-940: Is somewhat mitigated by their proven long service life of decades - and in some cases over a century, which is three to five times longer than utility-scale batteries. When electricity prices become negative , pumped hydro operators may earn twice - when "buying" the electricity to pump the water to the upper reservoir at negative spot prices and again when selling the electricity at a later time when prices are high. Along with energy management, pumped storage systems help stabilize electrical network frequency and provide reserve generation. Thermal plants are much less able to respond to sudden changes in electrical demand that potentially cause frequency and voltage instability. Pumped storage plants, like other hydroelectric plants, can respond to load changes within seconds. The most important use for pumped storage has traditionally been to balance baseload powerplants, but they may also be used to abate
1475-427: 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. The power station is required to keep a 12-hour water supply in order to provide a black start capability to
1534-486: Is variable speed machines for greater efficiency. These machines operate in synchronization with the network frequency when generating, but operate asynchronously (independent of the network frequency) when pumping. The first use of pumped-storage in the United States was in 1930 by the Connecticut Electric and Power Company, using a large reservoir located near New Milford, Connecticut, pumping water from
1593-475: The National Grid , to enable utilities to be restarted without access to external power. It began supplying grid inertia in 2020. In June 2021, Drax applied to build a further 600 MW pumped storage system using the same reservoir, to a combined 1 GW for seven hours of storage. Approval was granted in July 2023, and Drax intended to complete the project in 2030. Several financing modes are possible for
1652-623: The 240 MW Rance tidal power station in France can partially work as a pumped-storage station. When high tides occur at off-peak hours, the turbines can be used to pump more seawater into the reservoir than the high tide would have naturally brought in. It is the only large-scale power plant of its kind. In 1999, the 30 MW Yanbaru project in Okinawa was the first demonstration of seawater pumped storage. It has since been decommissioned. A 300 MW seawater-based Lanai Pumped Storage Project
1711-491: The 3 million abandoned wells in the US. Using hydraulic fracturing pressure can be stored underground in impermeable strata such as shale. The shale used contains no hydrocarbons. Small (or micro) applications for pumped storage could be built on streams and within infrastructures, such as drinking water networks and artificial snow-making infrastructures. In this regard, a storm-water basin has been concretely implemented as
1770-620: The EU. Japan had 25.5 GW net capacity (24.5% of world capacity). The six largest operational pumped-storage plants are listed below (for a detailed list see List of pumped-storage hydroelectric power stations ) : Australia has 15GW of pumped storage under construction or in development. Examples include: In June 2018 the Australian federal government announced that 14 sites had been identified in Tasmania for pumped storage hydro, with
1829-511: The Housatonic River to the storage reservoir 70 metres (230 ft) above. In 2009, world pumped storage generating capacity was 104 GW , while other sources claim 127 GW, which comprises the vast majority of all types of utility grade electric storage. The European Union had 38.3 GW net capacity (36.8% of world capacity) out of a total of 140 GW of hydropower and representing 5% of total net electrical capacity in
Cruachan Power Station - Misplaced Pages Continue
1888-567: The Kidston project under construction in Australia. Water requirements for PSH are small: about 1 gigalitre of initial fill water per gigawatt-hour of storage. This water is recycled uphill and back downhill between the two reservoirs for many decades, but evaporation losses (beyond what rainfall and any inflow from local waterways provide) must be replaced. Land requirements are also small: about 10 hectares per gigawatt-hour of storage, which
1947-453: The United States. As of late 2014, there were 51 active project proposals with a total of 39 GW of new nameplate capacity across all stages of the FERC licensing process for new pumped storage hydroelectric plants in the United States, but no new plants were currently under construction in the United States at the time. Conventional hydroelectric dams may also make use of pumped storage in
2006-573: The effective storage in about 2 trillion electric vehicle batteries), which is about 100 times more than needed to support 100% renewable electricity. Most are closed-loop systems away from rivers. Areas of natural beauty and new dams on rivers can be avoided because of the very large number of potential sites. Some projects utilise existing reservoirs (dubbed "bluefield") such as the 350 Gigawatt-hour Snowy 2.0 scheme under construction in Australia. Some recently proposed projects propose to take advantage of "brownfield" locations such as disused mines such as
2065-652: The efficiency of pumped storage by using fluid 2.5x denser than water ("a fine-milled suspended solid in water" ), such that "projects can be 2.5x smaller for the same power." The first use of pumped storage was in 1907 in Switzerland , at the Engeweiher pumped storage facility near Schaffhausen, Switzerland. In the 1930s reversible hydroelectric turbines became available. This apparatus could operate both as turbine generators and in reverse as electric motor-driven pumps. The latest in large-scale engineering technology
2124-488: The electric current up a cable shaft to a point in front of the dam, and from there it is carried on pylons to Dalmally 8 km (5.0 miles) to the east. The staircase in the cable shaft has 1,420 steps, making it the tallest in Britain. After passing through the turbines, the water enters a surge chamber designed to balance fluctuations in the level of water before entering the tailrace tunnel to Loch Awe, which
2183-418: The fluctuating output of intermittent energy sources . Pumped storage provides a load at times of high electricity output and low electricity demand, enabling additional system peak capacity. In certain jurisdictions, electricity prices may be close to zero or occasionally negative on occasions that there is more electrical generation available than there is load available to absorb it. Although at present this
2242-402: The fluctuating water level may make them unsuitable for recreational use). Nevertheless, some authors defend the technological simplicity and security of water supply as important externalities . The main requirement for PSH is hilly country. The global greenfield pumped hydro atlas lists more than 800,000 potential sites around the world with combined storage of 86 million GWh (equivalent to
2301-644: The form of gravitational potential energy of water, pumped from a lower elevation reservoir to a higher elevation. Low-cost surplus off-peak electric power is typically used to run the pumps. During periods of high electrical demand, the stored water is released through turbines to produce electric power. Pumped-storage hydroelectricity allows energy from intermittent sources (such as solar , wind , and other renewables) or excess electricity from continuous base-load sources (such as coal or nuclear) to be saved for periods of higher demand. The reservoirs used with pumped storage can be quite small, when contrasted with
2360-435: The grid. The quantity of power created when water is let in, grows proportionally to the height of the column of water above the sphere. In other words: the deeper the sphere is located, the more densely it can store energy. As such, the energy storage capacity of the submerged reservoir is not governed by the gravitational energy in the traditional sense, but by the vertical pressure variation . RheEnergise aim to improve
2419-415: The lakes of conventional hydroelectric plants of similar power capacity, and generating periods are often less than half a day. The round-trip efficiency of PSH varies between 70% and 80%. Although the losses of the pumping process make the plant a net consumer of energy overall, the system increases revenue by selling more electricity during periods of peak demand , when electricity prices are highest. If
Cruachan Power Station - Misplaced Pages Continue
2478-714: The largest PHES in the world at 5 GW. China has the largest capacity of pumped-storage hydroelectricity in the world. In January 2019, the State Grid Corporation of China announced plans to invest US$ 5.7 billion in five pumped hydro storage plants with a total 6 GW capacity, to be located in Hebei, Jilin, Zhejiang, Shandong provinces, and in Xinjiang Autonomous Region. China is seeking to build 40 GW of pumped hydro capacity installed by 2020. There are 9 power stations capable of pumping with
2537-489: The number of underground pumped storage opportunities may increase if abandoned coal mines prove suitable. In Bendigo , Victoria, Australia, the Bendigo Sustainability Group has proposed the use of the old gold mines under Bendigo for Pumped Hydro Energy Storage. Bendigo has the greatest concentration of deep shaft hard rock mines anywhere in the world with over 5,000 shafts sunk under Bendigo in
2596-628: The operation point in pumping usually differs from the operation point in PAT mode. In closed-loop systems, pure pumped-storage plants store water in an upper reservoir with no natural inflows, while pump-back plants utilize a combination of pumped storage and conventional hydroelectric plants with an upper reservoir that is replenished in part by natural inflows from a stream or river. Plants that do not use pumped storage are referred to as conventional hydroelectric plants; conventional hydroelectric plants that have significant storage capacity may be able to play
2655-432: The peak of the construction, there were around 4,000 people working on the project. Thirty-six men died in the construction of the power station and dam. The cost of the scheme was £24.5 million . Cruachan was one of the first reversible pumped-storage systems , where the same turbines are used as both pumps and generators. Previous pumped-storage systems used separate pumps with a network of pipes to return water to
2714-483: The potential of adding 4.8GW to the national grid if a second interconnector beneath Bass Strait was constructed. The Snowy 2.0 project will link two existing dams in the New South Wales' Snowy Mountains to provide 2,000 MW of capacity and 350,000 MWh of storage. In September 2022, a pumped hydroelectric storage (PHES) scheme was announced at Pioneer-Burdekin in central Queensland that has the potential to be
2773-554: The power grid, permitting thermal power stations such as coal-fired plants and nuclear power plants that provide base-load electricity to continue operating at peak efficiency, while reducing the need for "peaking" power plants that use the same fuels as many base-load thermal plants, gas and oil, but have been designed for flexibility rather than maximal efficiency. Hence pumped storage systems are crucial when coordinating large groups of heterogeneous generators . Capital costs for pumped-storage plants are relatively high, although this
2832-1075: The proposed Summit project in Norton, Ohio , the proposed Maysville project in Kentucky (underground limestone mine), and the Mount Hope project in New Jersey , which was to have used a former iron mine as the lower reservoir. The proposed energy storage at the Callio site in Pyhäjärvi ( Finland ) would utilize the deepest base metal mine in Europe, with 1,450 metres (4,760 ft) elevation difference. Several new underground pumped storage projects have been proposed. Cost-per-kilowatt estimates for these projects can be lower than for surface projects if they use existing underground mine space. There are limited opportunities involving suitable underground space, but
2891-713: The roof of the turbine hall collapsed, and the final section shows the station working. In the Disney+ Star Wars series Andor episode six "The Eye", the Cruachan Power Station appeared as the Empire's supply hub on the planet Aldhani. Pumped-storage hydroelectricity Pumped-storage hydroelectricity ( PSH ), or pumped hydroelectric energy storage ( PHES ), is a type of hydroelectric energy storage used by electric power systems for load balancing . A PSH system stores energy in
2950-619: The sea area replacing seawater by constructing coastal reservoirs . The stored river water is pumped to uplands by constructing a series of embankment canals and pumped storage hydroelectric stations for the purpose of energy storage, irrigation, industrial, municipal, rejuvenation of over exploited rivers, etc. These multipurpose coastal reservoir projects offer massive pumped-storage hydroelectric potential to utilize variable and intermittent solar and wind power that are carbon-neutral, clean, and renewable energy sources. The use of underground reservoirs has been investigated. Recent examples include
3009-430: The second half of the 19th Century. The deepest shaft extends 1,406 metres vertically underground. A recent pre-feasibility study has shown the concept to be viable with a generation capacity of 30 MW and a run time of 6 hours using a water head of over 750 metres. US-based start-up Quidnet Energy is exploring using abandoned oil and gas wells for pumped storage. If successful they hope to scale up, utilizing some of
SECTION 50
#17327734068273068-424: The total installed capacity of small pumped-storage hydropower plants in 2011 could be increased by 3 to 9 times by providing adequate policy instruments . Using a pumped-storage system of cisterns and small generators, pico hydro may also be effective for "closed loop" home energy generation systems. In March 2017, the research project StEnSea (Storing Energy at Sea) announced their successful completion of
3127-410: The upper lake collects significant rainfall, or is fed by a river, then the plant may be a net energy producer in the manner of a traditional hydroelectric plant. Pumped storage is by far the largest-capacity form of grid energy storage available, and, as of 2020 , accounts for around 95% of all active storage installations worldwide, with a total installed throughput capacity of over 181 GW and
3186-512: The upper reservoir, making them more expensive to build than conventional hydroelectric systems. Cruachan is pre-dated by the smaller 232 megawatts (311,000 hp) Lünerseewerk ( de ) (Austria, 1958) and the 360 megawatts (480,000 hp) Ffestiniog Power Station (Wales, 1963). It is one of four pumped storage schemes in the United Kingdom. Its construction was linked to that of Hunterston A nuclear power station , to store surplus night-time nuclear-generated electrical energy. The power station
3245-516: The £500M project. Seismic surveys began in June 2024. There are four Francis turbines , which operate as both pumps and generators. These are housed in a cavern within Ben Cruachan , which is 91.5 m (300 ft) long, 23.5 m (77 ft) wide and 38 m (125 ft) high, with an adjacent transformer hall. The chamber is at a depth of around 300 m (980 ft), and is within
3304-524: Was considered for Lanai, Hawaii, and seawater-based projects have been proposed in Ireland. A pair of proposed projects in the Atacama Desert in northern Chile would use 600 MW of photovoltaic solar (Skies of Tarapacá) together with 300 MW of pumped storage (Mirror of Tarapacá) lifting seawater 600 metres (2,000 ft) up a coastal cliff. Freshwater from the river floods is stored in
3363-461: Was listed by the conservation organisation DoCoMoMo as one of the sixty key monuments of post-war Scottish architecture. In November 2012, the power station received the Institution of Mechanical Engineers ' Engineering Heritage Award . A visitor centre , refurbished in 2009, is sited by the outflow to Loch Awe and receives around 50,000 visitors a year. The power station houses
3422-420: Was opened by Queen Elizabeth II on 15 October 1965. The concept was designed by Sir Edward MacColl , who died before it opened. The civil engineering design of the scheme was carried out by James Williamson & Partners of Glasgow, and the main project contractors were William Tawse of Aberdeen and Edmund Nuttall of Camberley. Consulting electrical engineers were Merz & McLellan of Newcastle upon Tyne. At
3481-511: Was originally operated by the North of Scotland Hydro-Electric Board , before being transferred to the South of Scotland Electricity Board . It was owned by ScottishPower from the privatisation of Britain's electricity industry in 1990 until Drax Group purchased it along with other ScottishPower assets on 1 January 2019. Maintenance of the penstocks , which formerly required them to be drained,
#826173