Unit 3 to be down for some time

By Knight Ridder Tribune


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Sixteen days after an unplanned shutdown, Browns Ferry Unit 3 remained offline and TVA was making no projections on when it would return to service.

"In this instance you had electrical equipment on the generator that is disassembled, being repaired," TVA spokes-man Gil Francis said. "It will be reassembled, and the unit will come back in service. They will do that as quickly as they can, but the No. 1 priority is to do it safely."

When operational, Unit 3 produces 1,155 megawatts of power, enough for about 650,000 homes. Because the unit is down, the Tennessee Valley Authority must find replacement power. "We've got interconnections to the marketplace to buy replacement power if needed, particularly when it's cheaper," Francis said.

"Or we can use other resources, whether it's combustion turbine, other coal plants, hydro plants, Raccoon Mountain. It's such a large system we have that flexibility."

Raccoon Mountain is an energy storage facility near Chattanooga. TVA pumps water to an elevated pool during non-peak hours, then releases the water to generate hydroelectric power during hours of peak demand. Unit 3 automatically shut down Dec. 31 when the main turbine generator received a load reject signal of unknown cause. All safety systems responded properly to the signal. A load reject signal causes the system to "think" that the generator has lost the attached load.

It is similar to the tires of a speeding vehicle losing contact with the road. With the load gone, there is a risk that the engine will overaccelerate, damaging the engine. Similarly, if TVA's safety systems failed, a false load reject signal could cause the turbine and attached generator to speed up to dangerous levels.

The repairs, according to one TVA spokesman, are focused on Unit 3's exciter. The exciter provides a source of direct current to the generator, which allows the generator to produce alternating current electricity. The alternating current electricity connects to the power grid through an output circuit breaker.

Shutdowns during August forced TVA to purchase high-priced power produced by natural gas turbines, but Francis said a January shutdown is unlikely to impact rates.

Power purchases in January are generally less expensive than in August because most systems are not running at full capacity. Francis said TVA does not keep statistics indicating how the length of the Unit 3 outage compares to other unplanned outages in TVA history.

"There is no list of unplanned outages where I can just pull it," he said. "Each outage is different." He said TVA uses unplanned outages to perform maintenance unrelated to the reason for the outage.

"You manage that outage to the best of your ability to take care of all the other issues that are pending," Francis said.

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Greening Ontario's electricity grid would cost $400 billion: report

Ontario Electricity Grid Decarbonization outlines the IESO's net-zero pathway: $400B investment, nuclear expansion, renewables, hydrogen, storage, and demand management to double capacity by 2050 while initiating a 2027 natural gas moratorium.

 

Key Points

A 2050 plan to double capacity, retire gas, and invest $400B in nuclear, renewables, and storage for a net-zero grid.

✅ $400B over 25 years to meet net-zero electricity by 2050

✅ Capacity doubles to 88,000 MW; demand grows ~2% annually

✅ 2027 gas moratorium; build nuclear, renewables, storage

 

Ontario will need to spend $400 billion over the next 25 years in order to decarbonize the electricity grid and embrace clean power according to a new report by the province’s electricity system manager that’s now being considered by the Ford government.

The Independent System Electricity Operator (IESO) was tasked with laying out a path to reducing Ontario’s reliance on natural gas for electricity generation and what it would take to decarbonize the entire electricity grid by 2050.

Meeting the goal, the IESO concluded, will require an “aggressive” approach of doubling the electricity capacity in Ontario over the next two-and-a-half decades — from 42,000 MW to 88,000 MW — by investing in nuclear, hydrogen and wind and solar power while implementing conservation policies and managing demand.

“The process of fully eliminating emissions from the grid itself will be a significant and complex undertaking,” IESO president Lesley Gallinger said in a news release.

The road to decarbonization, the IESO said, begins with a moratorium on natural gas power generation starting in 2027 as long as the province has “sufficient, non-emitting supply” to meet the growing demands on the grid.

The approach, however, comes with significant risks.

The IESO said hydroelectric and nuclear facilities can take 10 to 15 years to build and if costs aren’t controlled the plan could drive up the price of clean electricity, turning homeowners and businesses away from electrification.

“Rapidly rising electricity costs could discourage electrification, stifle economic growth or hurt consumers with low incomes,” the report states.

The IESO said the province will need to take several “no regret” actions, including selecting sites and planning to construct new large-scale nuclear plants as well as hydroelectric and energy storage projects and expanding energy-efficiency programs beyond 2024.

READ MORE: Ontario faces calls to dramatically increase energy efficiency rebate programs

Ontario’s minister of energy didn’t immediately commit to implementing the recommendations, citing the need to consult with stakeholders first.

“I look forward to launching a consultation in the new year on next steps from today’s report, including the potential development of major nuclear, hydroelectric and transmissions projects,” Todd Smith said in a statement.

Currently, electricity demand is increasing by roughly two per cent per year, raising concerns Ontario could be short of electricity in the coming years as the manufacturing and transportation sectors electrify and as more sectors consider decarbonization.

At the same time, the province’s energy supply is facing “downward pressure” with the Pickering nuclear power plant slated to wind down operations and the Darlington nuclear generating station under active refurbishment.

To meet the energy need, the Ford government said it intended to extend the life of the Pickering plant until 2026.

READ MORE: Ontario planning to keep Pickering nuclear power station open until 2026

But to prepare for the increase, the Ontario government was told the province would also need to build new natural gas facilities to bridge Ontario’s electricity supply gap in the near term — a recommendation the Ford government agreed to.

The IESO said a request for proposals has been opened and the province is looking for host communities, with the expectation that existing facilities would be upgraded before projects on undeveloped land would be considered.

The IESO said the contract for any new facilities would expire in 2040, and all natural gas facilities would be retired in the 2040s.

 

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Nuclear plants produce over half of Illinois electricity, almost faced retirement

Illinois Zero Emission Credits support nuclear plants via tradable credits tied to wholesale electricity prices, carbon costs, created by the Future Energy Jobs Bill to avert Exelon closures and sustain low-carbon power.

 

Key Points

State credits that value nuclear power's zero-carbon output, priced by market and carbon metrics to keep plants running.

✅ Pegged to wholesale prices, carbon costs, and state averages.

✅ Created by Future Energy Jobs Bill to prevent plant retirements.

✅ Supports Exelon Quad Cities and Clinton nuclear facilities.

 

Nuclear plants have produced over half of Illinois electricity generation since 2010, but the states two largest plants would have been retired amid the debate over saving nuclear plants if the state had not created a zero emission credit (ZEC) mechanism to support the facilities.

The two plants, Quad Cities and Clinton, collectively delivered more than 12 percent of the states electricity generation over the past several years. In May 2016, however, Exelon, the owner of the plants, announced that they had together lost over $800 million dollars over the previous six years and revealed plans to retire them in 2017 and 2018, similar to the Three Mile Island closure later announced for 2019 by its owner.

In December 2016, Illinois passed the Future Energy Jobs Bill, which established a zero emission credit (ZEC) mechanism

to support the plants financially. Exelon then cancelled its plans to retire the two facilities.

The ZEC is a tradable credit that represents the environmental attributes of one megawatt-hour of energy produced from the states nuclear plants. Its price is based on a number of factors that include wholesale electricity market prices, nuclear generation costs, state average market prices, and estimated costs of the long-term effects of carbon dioxide emissions.

The bill is set to take effect in June, but faces multiple court challenges as some utilities have expressed concerns that the ZEC violates the commerce clause and affects federal authority to regulate wholesale energy prices, amid gas-fired competition in nearby markets that shapes the revenue outlook.

Illinois ranks first in the United States for both generating capacity and net electricity generation from nuclear power, a resource many see as essential for net-zero emissions goals, and accounts for approximately one-eighth of the nuclear power generation in the nation.

 

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National Grid to lose Great Britain electricity role to independent operator

UK Future System Operator to replace National Grid as ESO, enabling smart grid reform, impartial system planning, vehicle-to-grid, long duration storage, and data-driven oversight to meet net zero and cut consumer energy costs.

 

Key Points

The UK Future System Operator is an independent ESO and planner, steering net zero with impartial data and smart grid coordination.

✅ Replaces National Grid ESO with independent system operator

✅ Enables smart grid, vehicle-to-grid, and long-duration storage

✅ Supports net zero, lower bills, and impartial system planning

 

The government plans to strip National Grid of its role keeping Great Britain’s lights on as part of a proposed “revolution’” in the electricity network driven by smart digital grid technologies.

The FTSE 100 company has played a role in managing the energy system of England, Scotland and Wales, including efforts such as a subsea power link that brings renewable power from Scotland to England (Northern Ireland has its own network). It is the electricity system operator, balancing supply and demand to ensure the electricity supply. But it will lose its place at the heart of the industry after government officials put forward plans to replace it with an independent “future system operator”.

The new system controller would help steer the country towards its climate targets, at the lowest cost to energy bill payers, by providing impartial data and advice after an overhaul of the rules governing the energy system to make it “fit for the future”.

The plans are part of a string of new proposals to help connect millions of electric cars, smart appliances and other green technologies to the energy system, and to fast-track grid connections nationwide, which government officials believe could help to save £10bn a year by 2050, and create up to 10,000 jobs for electricians, data scientists and engineers.

The new regulations aim to make it easier for electric cars to export electricity from their batteries back on to the power grid or to homes when needed. They could also help large-scale and long-duration batteries play a role in storing renewable energy, supported by infrastructure such as a 2GW substation helping integrate supply, so that it is available when solar and wind power generation levels are low.

Anne-Marie Trevelyan, the energy and climate change minister, said the rules would allow households to “take control of their energy use and save money” while helping to make sure there is clean electricity available “when and where it’s needed”.

She added: “We need to ensure our energy system can cope with the demands of the future. Smart technologies will help us to tackle climate change while making sure that the lights stay on and bills stay low.”

The energy regulator, Ofgem, raised concerns earlier this year that National Grid would face a “conflict of interest” in providing advice on the future electricity system because it also owns energy networks that stand to benefit financially from future investment plans. It called for a new independent operator to take its place.

Jonathan Brearley, Ofgem’s chief executive, said the UK requires a “revolution” in how and when it uses electricity, including demand shifts during self-isolation to help meet its climate targets and added that the government’s plans for a new digital energy system were “essential” to meeting this goal “while keeping energy bills affordable for everyone”.

A National Grid spokesperson said the company would “work closely” with the government and Ofgem on the role of a future system operator, as well as “the most appropriate ownership model and any future related sale”.

The division has earned National Grid, which has addressed cybersecurity fears in supplier choices, an average of £199m a year over the last five years, or 1.3% of the group’s total revenues, which are split between the UK – where it operates high-voltage transmission lines in England and Wales, and the country’s gas system – and its growing energy supply business in the US, aligned with investment in a smarter electricity infrastructure in the US to modernize grids.

 

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Cooperation agreement for Rosatom and Russian Academy

Rosatom-RAS Cooperation drives joint R&D in nuclear energy, nuclear medicine, fusion, particle accelerators, laser technologies, fuel cycle safety, radioactive waste management, and supercomputing, aligning strategic planning and standards to accelerate innovation across Russia's nuclear sector.

 

Key Points

A pact uniting Rosatom and RAS on nuclear R&D, fusion, and medicine to advance nuclear technologies across Russia.

✅ Joint R&D in fusion, accelerators, lasers, and new materials

✅ Focus on fuel cycle closure, safety, and waste management

✅ Shared strategic planning, standards, and expert evaluation

 

Russian state atomic energy corporation Rosatom and the Russian State Academy of Sciences are to cooperate on joint scientific, technical and innovative activities in areas including nuclear energy, nuclear medicine and other areas of the electricity sector under an agreement signed in Moscow on 7 February.

The cooperation agreement was signed by Rosatom Director General Alexei Likhachov and President of the Russian Academy of Sciences Alexander Sergeev during a joint meeting to mark Russian Science Day. Under its terms, the partners will cooperate in organising research and development activities aimed at providing technological advantages in various sectors of the domestic industry, as well as creating and developing interdisciplinary scientific and technological centres and organisations supporting energy sector training and innovation. They will also jointly develop strategic planning documents, improve the technical and scientific regulatory and legal framework, and carry out expert evaluations of scientific and technical projects and scientific consultations.

Rosatom said the main areas of cooperation in the agreement are: the development of laser technologies and particle accelerators; the creation of modern diagnostic equipment, nuclear medicine and radiation therapy; controlled thermonuclear fusion; nuclear energy of the future; new materials; the nuclear fuel cycle and its closure; safety of nuclear energy and power sector pandemic response preparedness; environmental aspects of radioactive waste management; modern supercomputers, databases, application packages, and import-substituting codes; and also X-ray astronomy and nuclear planetology.

Likhachov said joint activities between Rosatom and the Academy would strengthen the Russian nuclear industry's "leadership" in the world and allow the creation of new technologies that would shape the future image of the nuclear industry in Russia. "Within the framework of the Agreement, we intend to expand work on the entire spectrum of advanced scientific research. The most important direction of our cooperation will be the integration of fundamental, exploratory and applied scientific research, including in the interests of the development of the nuclear industry. We will work together to form the nuclear energy industry of the future, and enhance grid resilience, to create new materials, new radiation technologies,” he said.

Sergeyev noted the "rich history" of cooperation between the Academy of Sciences and the nuclear industry, including modern safety practices such as arc flash training that support operations. “All major projects in the field of military and peaceful nuclear energy were carried out jointly by scientists and specialists of our organisations, which largely ensured their timeliness and success," he said.

 

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Energy Vault Secures $28M for California Green Hydrogen Microgrid

Calistoga Resiliency Centre Microgrid delivers grid resilience via green hydrogen and BESS, providing island-mode backup during PSPS events, wildfire risk, and outages, with black-start and grid-forming capabilities for reliable community power.

 

Key Points

A hybrid green hydrogen and BESS facility ensuring resilient, islanded power for Calistoga during PSPS and outages.

✅ 293 MWh capacity with 8.5 MW peak for critical backup

✅ Hybrid lithium-ion BESS plus green hydrogen fuel cells

✅ Island mode with black-start and grid-forming support

 

Energy Vault, a prominent energy storage and technology company known for its gravity storage, recently secured US$28 million in project financing for its innovative Calistoga Resiliency Centre (CRC) in California. This funding will enable the development of a microgrid powered by a unique combination of green hydrogen and battery energy storage systems (BESS), marking a significant step forward in enhancing grid resilience in the face of natural disasters such as wildfires.

Located in California's fire-prone regions, the CRC is designed to provide critical backup power during Public Safety Power Shutoff (PSPS) events—periods when utility companies proactively cut power to prevent wildfires. These events can leave communities without electricity for extended periods, making the need for reliable, independent power sources more urgent as many utilities see benefits in energy storage today. The CRC, with a capacity of 293 MWh and a peak output of 8.5 MW, will ensure that the Calistoga community maintains power even when the grid is disconnected.

The CRC features an integrated hybrid system that combines lithium-ion batteries and green hydrogen fuel cells, even as some grid-scale projects adopt vanadium flow batteries for long-duration needs. During a PSPS event or other grid outages, the system will operate in "island mode," using hydrogen to generate electricity. This setup not only guarantees power supply but also contributes to grid stability by supporting black-start and grid-forming functions. Energy Vault's proprietary B-VAULT DC battery technology complements the hydrogen fuel cells, enhancing the overall performance and resilience of the microgrid.

One of the key aspects of the CRC project is the utilization of green hydrogen. Unlike traditional hydrogen, which is often produced using fossil fuels, green hydrogen is generated through renewable energy sources like solar or wind power, with large-scale initiatives such as British Columbia hydrogen project accelerating supply, making it a cleaner and more sustainable alternative. This aligns with California’s ambitious clean energy goals and is expected to reduce the carbon footprint of the region’s energy infrastructure.

The CRC project also sets a precedent for future hybrid microgrid deployments across California and other wildfire-prone areas, with utilities like SDG&E Emerald Storage highlighting growing adoption. Energy Vault has positioned the CRC as a model for scalable, utility-scale microgrids that can be adapted to various locations facing similar challenges. Following the success of this project, Energy Vault is expanding its portfolio with additional projects in Texas, where it anticipates securing up to US$25 million in financing.

The funding for the CRC also includes the sale of an investment tax credit (ITC), a key component of the financing structure that helps make such ambitious projects financially viable. This structure is crucial as it allows companies to leverage government incentives to offset development costs, including CEC long-duration storage funding, thus encouraging further investment in green energy infrastructure.

Despite some skepticism regarding the transportation of hydrogen rather than producing it onsite, the project has garnered strong support. California’s Public Utilities Commission (CPUC) acknowledged the potential risks of transporting green hydrogen but emphasized that it is still preferable to using more harmful fuel sources. This recognition is important as it validates Energy Vault’s approach to using hydrogen as part of a broader strategy to transition to clean, reliable energy solutions.

Energy Vault's shift from its traditional gravity-based energy storage systems to battery energy storage systems, such as BESS in New York, reflects the company's adaptation to the growing demand for versatile, efficient energy solutions. The hybrid approach of combining BESS with green hydrogen represents an innovative way to address the challenges of energy storage, especially in regions vulnerable to natural disasters and power outages.

As the CRC nears mechanical completion and aims for full commercial operations by Q2 2025, it is poised to become a critical part of California’s grid resilience strategy. The microgrid's ability to function autonomously during emergencies will provide invaluable benefits not only to Calistoga but also to other communities that may face similar grid disruptions in the future.

Energy Vault’s US$28 million financing for the Calistoga Resiliency Centre marks a significant milestone in the development of hybrid microgrids that combine the power of green hydrogen and battery energy storage. This project exemplifies the future of energy resilience, showcasing a forward-thinking approach to mitigating the impact of natural disasters and ensuring a reliable, sustainable energy future for communities at risk. With its innovative use of renewable energy sources and cutting-edge technology, the CRC sets a strong example for future energy storage projects worldwide.

 

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"Kill the viability": big batteries to lose out from electricity grid rule change

AEMC Storage Charging Rules spark industry backlash as Tesla, Snowy Hydro, and investors warn transmission charges on batteries and pumped hydro could deter grid-scale storage, distort the National Electricity Market, and slow decarbonisation.

 

Key Points

AEMC Storage Charging Rules are proposals to bill grid storage for network use, shaping costs and investment.

✅ Charges apply when batteries draw power; double-charging concerns.

✅ Tesla and Snowy Hydro warn of reduced viability and delays.

✅ AEMO recommends exemptions; investors seek certainty.

 

Tesla, Snowy Hydro and other big suppliers of storage capacity on Australia’s main electricity grid warn proposed rule changes amount to a tax on their operations that will deter investors and slow the decarbonisation of the industry.

The Australian Energy Market Commission (AEMC) will release its final decision this Thursday on new rules for integrating batteries, pumped hydro and other forms of storage.

The AEMC’s draft decision, released in July, angered many firms because it proposed charging storage providers for drawing power, ignoring a recommendation by the Australian Electricity Market Operator (AEMO) that they be exempt.

Battery maker Tesla, which has supplied some of the largest storage to the National Electricity Market, said in a submission that the charges would “kill the commercial viability of all grid storage projects, causing inefficient investment in alternative network”, with consumers paying higher costs.

Snowy Hydro, which is building the giant Snowy 2 pumped storage project and already operates a smaller one, said in its submission the proposed changes if implemented would jeopardise investment.

“This is a major policy change, amounting to a tax on infrastructure critical to achieving a renewable future,” Snowy Hydro said.

AEMO itself argued it was important storage providers were not “disincentivised from connecting to the transmission network, as they generally provide a net benefit to the power system by charging at periods of low demand”.

Australia’s electricity grid faces economic and engineering challenges, similar to Ontario's storage push as it adjusts to the arrival of lower cost and also lower carbon alternatives to fossil fuels.

While rule changes are necessary to account for operators that can both draw from and supply power, how they are implemented can have long-lasting effects on the technologies that get encouraged or repelled, including control of EV charging issues, independent experts say.

“It doesn’t have to be this way,” said Bruce Mountain, director of the Victoria Energy Policy Centre. “In Britain, where the UK grid transformation is underway, the regulator dealing with the same issues has said that storage devices don’t pay the system charges when they withdraw electricity from the grid,” he said.

The prospect that storage operators will have to pay transmission charges could “drastically” affect their profitability since their business models rely on the difference between the price their pay for power and how much they can sell it for. Gas generators and network monopolies would benefit from the change, Mountain said.

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An AEMC spokesperson said the commission had consulted widely, including from those who objected to the payment for transmission access.

“The market is moving towards a future that will be increasingly reliant on energy storage to firm up the growing volume of renewable energy and deliver on the increasing need for critical system security services, with examples such as EVs supporting grid stability in California as the ageing fleet of thermal generators retire,” the spokesperson said, declining to elaborate on the final ruling before it is published.

“The regulatory framework needs to facilitate this transition as the energy sector continues to decarbonise,” the official said.

AusNet, which operates the Victorian energy transmission grid, said that while “technological neutrality is paramount for battery and hybrid unit connections to both the distribution and transmission networks,” it did not back charging storage access to networks in all cases.

“[Ausnet] supports a clear exemptions framework for energy storage providers,” a spokesperson said. “We recommend that batteries and other hybrid facilities should have transmission use of system charges waived if they provide a net benefit to network customers.”

We are not aware of anyone that supports the charging storage access to networks in all circumstances.

“Batteries and hybrid facilities that consume energy from the network should be provided no preferential treatment relative to other customers and generators.”

Jonathan Upson, a principal at Strategic Renewable Consulting, though, said the AEMC wants electricity flowing through batteries to be taxed twice to pay network charges – once when the electricity charges the battery and then again when the same electricity is sent out by the battery an hour or two later but this time with customers paying.

“The AEMC’s draft decision has the identical rationale for eliminating franking credits on all dividends, resulting in double taxing of company profits,” he said.

Christiaan Zuur, director of energy transformation at the Clean Energy Council, said that while much of AEMC’s draft proposal was constructive, “those benefits are either nullified or maybe even outweighed” by uncertainty over charges.

“Risk perception” will be important since potential newcomers won’t be sure of what charges they will pay to connect to the grid and existing operators could have their connection agreements reopened, Zuur said.

“Investors focus on the potential risk. It does factor through to the integral costs for projects,” he said.

The outcome of new charges may prompt more people to put batteries on their premises and draw power from their own solar panels, Mountain said, with rising EV adoption introducing new grid challenges, cutting their reliance on a centralised network.

“Ironically, it encourages customers to depend less and less on the grid,” he said. “It’s almost like the capture of the dominant interests playing out over time at their own expense.”

Separately, the latest edition of the Clean Energy Council Confidence Index shows leadership by state governments is helping to shore up investor appetite for investing in renewable energy amid 2021 electricity lessons even with higher 2030 emissions reduction goals from the federal government.

Overall, investor confidence increased by a point in the last six months – from 6.3 to 7.3 out of 10 – following strong commitments and policy development from state governments, particularly on the east coast, the council said.

“The results of this latest survey illustrate the economic value in policy that lowers the emissions footprint of our electricity generation, supporting regional centres and creating jobs. Investors recognise the opportunities created by limiting global temperature rise to 1.5 degrees,” said council chief executive Kane Thornton.

Among the states, NSW, Victoria and Queensland led in terms of positive investor sentiment.

Correction: this article was amended on 30 November. An earlier version stated Ausnet supported charging storage for network access. A spokesperson said it backed a waiver on charges if certain conditions are met.        

 

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