Scientists at the University of Tennessee, Knoxville, and Oak Ridge National Laboratory in the US developed an algorithm to predict electric grid stability using signals from pumped storage hydropower projects. The method provides critical situational awareness as the grid increasingly shifts to intermittent renewable power.
When pumps shut down, they almost always stop at a fixed power level and this, Yilu Liu, lead for the project and UT-ORNL Governor’s Chair for Power Grids, says is a very defined signal on the grid that can help calculate overall inertia.
Generation sources such as solar and wind currently provide a minimal amount of inertia. They’re connected to the grid using inverters that convert the direct current power generated by renewables to the alternating current used to transmit electricity over long distances. The result is that grids reliant on inverter-connected renewable energy have less tolerance to abrupt change such as storm damage or unusual demand peaks.
Liu and colleagues have created a new algorithm that captures the pumped storage signal and uses it along with information gathered from unique, low-cost grid sensors previously deployed across the country. Called FNET/GridEye, this sensing and measurement system was developed by ORNL and University of Tennessee researchers to monitor the grid across a wide area. Together, the pumped storage signal and sensor data produce a real-time, highly accurate estimation of grid inertia.
To make it easier for grid operators to monitor inertia using the algorithm and better prepare for potential grid instability, the researchers created a visualisation interface. The new method was validated with the help of utilities and power regulating authorities in the western and eastern US where pumped storage hydropower is most prevalent.
The visualisation tool is being demonstrated to utilities and grid coordinating authorities such as the North American Electric Reliability Corporation, and Liu is confident that it will become more important for grid situational awareness as the system grows increasingly reliant on renewables.
“Through this project we can demonstrate how important inertia is, and how pumped storage hydro can contribute to it, especially as we are looking at more intermittent renewable energy sources added to the grid,” said Shih-Chieh Kao, manager of the Water Power Programme at ORNL.
Swiss stepping stone
In a move to explore opportunities for enhancing the UK’s renewable energy landscape, Labour Shadow Secretary of State for Scotland, Ian Murray MP, embarked on a fact-finding mission to the Nant de Drance pumped storage hydroelectric project in Switzerland. The visit, conducted in collaboration with companies including Glen Earrach Energy (GEE), Green Highland, Alpiq, and AECOM, aimed to glean insights into the potential integration of similar technologies in the UK.
The visit comes at a crucial time, coinciding with the UK government’s emphasis on bolstering energy storage capabilities and Labour’s commitment to position Britain as a clean energy superpower.
The backdrop of the UK government’s ongoing consultation on the policy framework for long-duration electricity storage (LDES) adds significance to Murray’s exploration of the Nant de Drance project. The Labour Party has pledged to invest in long-duration energy storage to ensure a reliable zero-emission backup power supply during periods without wind or sun. The commitment also includes maintaining a strategic reserve of backup gas power stations to guarantee energy security.
The tour to the Nant de Drance project, which was commissioned in 2022, provided essential lessons for the UK, particularly in the context of the country not having seen the development of new pumped storage hydro facilities since 1984. Murray and the delegation learned about creating a pro-growth investment framework to unlock the sector’s full potential in Scotland, along with strategies to maximise community benefits and minimise the environmental impact of large-scale engineering projects.
Reflecting on the visit, Murray said: “Under Labour’s vision, Scotland is set to become a global leader in green energy. This visit to the Nant de Drance project is a stepping stone towards realising that ambition. Our goal is clear – deliver clean energy by 2030, support the creation of thousands of jobs, and ensure energy security.”
Glen Earrach Energy (GEE) Director, Roderick MacLeod, expressed gratitude for Murray’s presence, describing it as invaluable. He pointed out the pioneering nature of the Nant de Drance project and its potential application to GEE’s proposed Loch Ness project that is anticipated to play a crucial role in the UK’s energy future.
The 900MW Nant de Drance scheme is one of the most powerful pumped storage plants in Europe. Located 600m underground between the Emosson and Vieux Emosson reservoirs, with a storage capacity of 20M kWh it offers flexible power generation and plays a key role in stabilising the electricity grid throughout Europe, as well as safeguarding Switzerland’s power supply.
Indigenous participation
In Canada, TC Energy Corporation has announced that it will continue to advance the Ontario Pumped Storage Project with its prospective partner Saugeen Ojibway Nation, and begin work with the Ministry of Energy and the Ontario Energy Board (OEB) to establish a potential long-term revenue framework for the project. TC Energy and Saugeen Ojibway Nation will assist with the ministry’s evaluation of the assessment of the broader societal and economic benefits linked to the initiative.
This decision comes after Ontario’s Minister of Energy outlined a roadmap for the pumped storage project, including the negotiation of a cost recovery agreement with the Independent Electricity System Operator (IESO). Pending an agreement with the IESO, this strategic move will facilitate the ongoing development of the project, in line with Ontario’s long-term vision for economic growth and the establishment of a sustainable, reliable, and clean electricity system.
Annesley Wallace, Executive Vice-President of Strategy and Corporate Development, and President of Power and Energy Solutions at TC Energy, emphasised the importance of the Minister’s direction. She said: “It recognises the critical role that pumped hydro storage will have in enhancing the diversity of Ontario’s supply mix and achieving a net-zero electricity grid.”
Looking ahead, TC Energy will collaborate with the Ministry and the OEB to establish a potential long-term revenue framework for the project, culminating in a report to the Minister by 31 July 2024. Following submission of this, along with a detailed report outlining estimated development costs and schedules, the Ministry will provide a recommendation to proceed with pre-development work within 45 days.
The initiative is expected to be a cornerstone in Ontario’s energy landscape, designed, engineered, and built by a domestic supply chain, creating 1000 well-paid jobs and sourcing over 75% of materials locally. Construction is anticipated to commence in the latter part of this decade, with commissioning projected for the early 2030s, contingent upon regulatory and corporate approvals.
Conrad Ritchie, Chief of Saugeen First Nation, and Gregory Nadjiwon, Chief of Chippewas of Nawash Unceded First Nation, underscored the significance of Indigenous participation in electricity development. As Ritchie noted: “The Ontario Pumped Storage Project is a long overdue energy initiative with real benefits for the Indigenous people of the land.”
If developed, the 1000MW facility would be co-located on the existing Canadian Army’s 4th Canadian Division Training Centre, north of Meaford in Ontario.
Greek milestone
Hailed as the largest grid energy storage investment in Greece and a milestone project for the country’s clean energy transition, Terna SA, the construction branch of the Gekterna Group, has chosen Andritz to supply electromechanical equipment for the Amfilochia pumped storage complex in Central Greece.
Upon completion and commencement of operations, the Amfilochia complex is expected to boast a total installed capacity of 680MW for generation and 730MW for pumping. The power plant aims to produce approximately 816GWh of clean and sustainable electrical energy annually.
Andritz’s involvement in the scheme encompasses the design, manufacture, supervision of erection, and commissioning of six reversible pump-turbine generator units. The scope also includes various associated auxiliaries and ancillary equipment, governors, excitation and protection systems, main inlet valves, draft tube gates, and digital services.
Snowy breakthrough
Snowy Hydro has announced a significant milestone for the Snowy 2.0 pumped storage hydropower project, as the final metres of the power station’s 223m long transformer hall cavern crown have been successfully breached in Australia.
Initiated in June 2023, the Snowy 2.0 delivery team embarked on the excavation of the transformer hall and machine hall caverns, nestled approximately 800m underground at Lobs Hole in the Snowy Mountains.
To date, approximately 17,000m3 of material have been excavated from the central heading of the transformer hall cavern crown, employing a systematic advancement in 3-4m rounds from both ends of the cavern through a total of 77 blasts.
Breakthrough of the machine hall cavern crown, along with the ongoing side slashing to widen both cavern crowns, will be next with excavation activities for both power station caverns scheduled to persist throughout 2024.
As Snowy 2.0 Project Director Dave Evans says, such milestones are only possible with the whole team working together as one, whether they are subcontractors like Orica, the company managing underground blasting operations, or the lead contractor Future Generation and Snowy working so closely together.
Upon completion Snowy 2.0 will augment the existing Snowy Scheme by contributing an additional 2200MW of on-demand power and 160 hours of large-scale renewable energy storage to the National Electricity Market.
“We are well on our way to delivering the largest single project that will help ensure Australia’s secure and reliable transition to renewable energy,” Snowy Hydro CEO Dennis Barnes stated. “The breakthrough of the transformer hall cavern crown is a really pleasing milestone for the Snowy 2.0 team, reinforcing that we’re making good progress with our underground drill and blast excavation activities. “
Major milestone for Borumba
In a significant development for the Borumba Pumped Storage Hydro Project, Queensland Hydro has unveiled two Request for Tenders (RFTs), marking a crucial phase in the exploratory works programme set to shape region’s renewable energy future.
These tenders form an integral part of the broader exploratory works aimed at gaining deeper insights into the surface geotechnical and groundwater conditions within the expansive footprint of the scheme.
As Leah McKenzie, Borumba Project Director, said: “These new packages are a major step forward in the exploratory works programme. Pumped hydro has a proven global track record and is key to achieving Queensland’s renewable energy targets. It provides advanced clean energy generation and clean energy storage sized for our growing state. The shift to renewable energy is now a ‘must-do,’ not a ‘might-do’,” she added.
With tenders closing in February 2024, contract awards are scheduled for the second quarter of 2024.
New project in Finland
Finland has announced plans to build up to three small-scale pumped storage hydropower plants in the northern part of the country to bolster its green transition and enhance energy balance.
Suomen Voima announced details of this new €300 million energy storage venture called Noste, in the Kemijärvi region.
While pumped storage production is relatively unfamiliar in Finland, there is a substantial demand for efficient energy storage solutions. Noste is anticipated to contribute 100-200MW of balancing power, providing a crucial element for Finland’s move towards sustainable energy infrastructure.
The project aims to employ state-of-the-art technology, with a paramount focus on designing pumped storage facilities that minimise their impact on the northern environment and landscape. Suomen Voima said it is committed to reducing any adverse effects on residential and recreational areas. The investment is also expected to spur positive developments in employment, tax revenues, and rental income during both the construction and operational phases. The first hydropower plant is slated to commence operations within the current decade.
Negotiations with landowners have begun and Suomen Voima says it is committed to maintaining an open dialogue with residents, businesses, and other local stakeholders to ensure a seamless collaboration during the project preparation phase.
Indian MoU
India’s NHPC has sealed a Memorandum of Understanding with Gujarat Power Corporation Limited (GPCL), Government of Gujarat, for a substantial investment in the 750MW Kuppa pumped storage hydropower project.
Under the terms outlined in the MoU, NHPC commits to injecting an estimated Rs 4000 crores into the proposed project, strategically located at Chhota Udaipur in Gujarat. This collaboration aligns with the broader national vision of achieving 500GW of renewable energy by 2030 and attaining Net Zero by 2070.
This article first appeared in International Water Power Magazine.
