Two TVA plants taken offline

By Knoxville News Sentinel


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With TVA already experiencing unprecedented fuel costs and buying more power than ever from outside suppliers, two TVA nuclear plants have been taken offline and two more are operating at 50 percent capacity at the agency's Watts Bar and Browns Ferry sites.

One unit at the Browns Ferry site in northern Alabama was pulled completely offline the morning of August 8 following the discovery of a leak in instrumentation used to monitor temperatures in the plant's main steam lines.

In an unrelated incident the day before, all three Browns Ferry units were reduced to 50 percent power following the failure of a transformer that supplies electricity to cooling tower equipment. Power was reduced in order to keep the temperature of water released from the plant into the river system within regulatory limits, said TVA spokesman John Moulton.

"We never exceeded the thermal limit, which is 90 degrees," Moulton said.

The Watts Bar plant was taken offline August 7 to repair a hydrogen leak inside the main generator that workers have been monitoring since August 1. Power has been decreased incrementally since that time, Moulton said, and with a recent cooling trend it was decided to bring the plant completely offline to make the repair.

Moulton would not say when the plants would be back in operation, calling that information proprietary.

At capacity, Browns Ferry can produce 3,440 megawatts of power, enough to supply 1.3 million homes. Watts Bar, near Spring City, Tenn., has a capacity of about 1,100 megawatts, supplying the equivalent of 650,000 homes. As a result of the outages, TVA has lost approximately 2,255 megawatts of generating capacity.

The shutdowns follow on the heels of an announcement by TVA that customers can expect a sizable increase in their fall electric bills because of spikes in the cost of coal and natural gas, which affect TVA's generating plants and the power it buys from outside suppliers. The agency also said the lingering drought has reduced the amount of hydropower that can be generated by TVA dams and that it has bought 11 percent more power on the open market than during the same period last year.

The financial impact of the most recent incidents won't be known until the outages are over, said Moulton. But a break in the August heat wave should help, he said.

Demand for power was expected to be about 26,200 megawatts, a drop from hotter days earlier in the week when demand ranged from 30,0000 to 31,000 megawatts, Moulton said.

"The fact that we don't have two nuclear units available of course isn't what it would be on a day of high demand," he said. "The price of power right now is about 15 to 20 percent lower than it was earlier in the week."

Moulton called the simultaneous mechanical issues at the plants "unusual" but said that planning for such outages is part of the business.

"You want to keep them to a minimum, but you take it into account," he said. "We know that we're going to have some unplanned shutdowns, and that's taken into account as far as how you're going to meet the demand."

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Calgary's electricity use soars in frigid February, Enmax says

Calgary Winter Energy Usage Surge highlights soaring electricity demand, added megawatt-hours, and grid reliability challenges driven by extreme cold, heating loads, and climate change, with summer air conditioning also shifting seasonal peaks.

 

Key Points

A spike in Calgary's power use from extreme cold, adding 22k MWh and testing reliability as heating demand rises.

✅ +22,000 MWh vs Feb 2018 amid fourth-coldest February

✅ Heating loads spike; summer A/C now drives peak demand

✅ Grid reliability monitored; more solar and green resources ahead

 

February was so cold in Calgary that the city used enough extra energy to power 3,400 homes for a whole year, echoing record-breaking demand in B.C. in 2021 during severe cold.

Enmax Power Corporation, the primary electricity utility in the city, says the city 's energy consumption was up 22,000 megawatt hours last month compared with Februray 2018.

"We've seen through this cold period our system has held up very well. It's been very reliable," Enmax vice-president Andre van Dijk told the Calgary Eyeopener on Friday. "You know, in the absence of a windstorm combined with cold temperatures and that sort of thing, the system has actually held up pretty well."

The past month was the fourth coldest in Calgary's history, and similar conditions have pushed all-time high demand in B.C. in recent years across the West. The average temperature for last month was –18.1 C. The long-term average for February is –5.4 C.

 

Watching use, predicting issues

The electricity company monitors demand and load on a daily basis, always trying to predict issues before they happen, van Dijk said, and utilities have introduced winter payment plans to help customers manage bills during prolonged cold.

One of the issues they're watching is climate change, and how extreme temperatures and weather affect both the grid's reliability, as seen when Quebec shattered consumption records during cold snaps, and the public's energy use.

The colder it gets, the higher you turn up the heat. The hotter it is, the more you use air conditioning.

He also noted that using fuels then contributes to climate change, creating a cycle.

​"We are seeing variations in temperature and we've seen large weather events across the continent, across the world, in fact, that impact electrical systems, whether that's flooding, as we've experienced here, or high winds, tornadoes," van Dijk said.

"Climate change and changing weather patterns have definitely had had an impact on us as an electrical industry."

In 2012, he said, Calgary switched from using the most power during winter to using the most during summer, in large part due to air conditioning, he said.

"Temperature is a strong influencer of energy consumption and of our demand," van Dijk said.

Christmas tree lights have also become primarily LED, van Dijk said, which cuts down on a big energy draw in the winter.

He said he expects more solar and other green resources will be added into the electrical system in the future to mitigate how much the increasingly levels of energy use impact climate change, and to help moderate electricity costs in Alberta over time.

 

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IAEA - COVID-19 and Low Carbon Electricity Lessons for the Future

Nuclear Power Resilience During COVID-19 shows low-carbon electricity supporting renewables integration with grid flexibility, reliability, and inertia, sustaining decarbonization, stable baseload, and system security while prices fell and demand dropped across markets.

 

Key Points

It shows nuclear plants providing reliable, low-carbon power and supporting grid stability despite demand declines.

✅ Low prices challenge investment; lifetime extensions are cost-effective.

✅ Nuclear provides inertia, reliability, and dispatchable capacity.

✅ Market reforms should reward flexibility and grid services.

 

The COVID-19 pandemic has transformed the operation of power systems across the globe, including European responses that many argue accelerated the transition, and offered a glimpse of a future electricity mix dominated by low carbon sources.

The performance of nuclear power, in particular, demonstrates how it can support the transition to a resilient, clean energy system well beyond the COVID-19 recovery phase, and its role in net-zero pathways is increasingly highlighted by analysts today.

Restrictions on economic and social activity during the COVID-19 outbreak have led to an unprecedented and sustained decline in demand for electricity in many countries, in the order of 10% or more relative to 2019 levels over a period of a few months, thereby creating challenging conditions for both electricity generators and system operators (Fig. 1). The recent Sustainable Recovery Report by the International Energy Agency (IEA) projects a 5% reduction in global electricity usage for the entire year 2020, with a record 5.7% decline foreseen in the United States alone. The sustainable economic recovery will be discussed at today's IEA Clean Energy Transitions Summit, where Fatih Birol's call to keep options open will be prominent as IAEA Director General Rafael Mariano Grossi participates.

Electricity generation from fossil fuels has been hard hit, due to relatively high operating costs compared to nuclear power and renewables, as well as simple price-setting mechanisms on electricity markets. By contrast, low-carbon electricity prevailed during these extraordinary circumstances, with the contribution of renewable electricity rising in a number of countries as analyses see renewables eclipsing coal by 2025, due to an obligation on transmission system operators to schedule and dispatch renewable electricity ahead of other generators, as well as due to favourable weather conditions.

Nuclear power generation also proved to be resilient, reliable and adaptable. The nuclear industry rapidly implemented special measures to cope with the pandemic, avoiding the need to shut down plants due to the effects of COVID-19 on the workforce or supply chains. Nuclear generators also swiftly adapted to the changed market conditions. For example, EDF Energy was able to respond to the need of the UK grid operator by curtailing sporadically the generation of its Sizewell B reactor and maintain a cost-efficient and secure electricity service for consumers.

Despite the nuclear industry's performance during the pandemic, faced with significant decreases in demand, many generators have still needed to reduce their overall output appreciably, for example in France, Sweden, Ukraine, the UK and to a lesser extent Germany (Fig. 2), even as the nuclear decline debate continues in Europe. Declining demand in France up to the end of March already contributed to a 1% drop in first quarter revenues at EDF, with nuclear output more than 9% lower than in the year before. Similarly, Russia's Rosatom experienced a significant demand contraction in April and May, contributing to an 11% decline in revenues for the first five months of the year.

Overall, the competitiveness and resilience of low carbon technologies have resulted in higher market shares for nuclear, solar and wind power in many countries since the start of lockdowns (Fig. 3), and low-emissions sources to meet demand growth over the next three years. The share of nuclear generation in South Korea rose by almost 9 percentage points during the pandemic, while in the UK, nuclear played a big part in almost eliminating coal generation for a period of two months. For the whole of 2020, the US Energy Information Administration's Short-Term Energy Outlook sees the share of nuclear generation increasing by more than one percentage point compared to 2019. In China, power production decreased during January-February 2020 by more than 8% year on year: coal power decreased by nearly 9%, hydropower by nearly 12%. Nuclear has proved more resilient with a 2% reduction only. The benefits of these higher shares of clean energy in terms of reduced emissions of greenhouse gases and other air pollutants have been on full display worldwide over the past months.

Challenges for the future

Despite the demonstrated performance of a cleaner energy system through the crisis - including the capacity of existing nuclear power plants to deliver a competitive, reliable, and low carbon electricity service when needed - both short- and long-term challenges remain.

In the shorter term, the collapse in electricity demand has accelerated recent falls in electricity prices, particularly in Europe (Fig. 4), from already economically unsustainable levels. According to Standard and Poor's Midyear Update, the large price drops in Europe result from not only COVID-19 lockdown measures but also collapsing demand due to an unusually warm winter, increased supply from renewables in a context of lower gas prices and CO2 allowances . Such low prices further exacerbate the challenging environment faced by many electricity generators, including nuclear plants. These may impede the required investments in the clean energy transition, with longer term consequences on the achievement of climate goals.

For nuclear power, maintaining and extending the operation of existing plants is essential to support and accelerate the transition to low carbon energy systems. With a supportive investment environment, a 10-20 year lifetime extension can be realized at an average cost of US $30-40/MW*h, making it among the most cost-effective low-carbon options, while also maintaining dispatchable capacity and lowering the overall cost of the clean energy transition. The IEA Sustainable Recovery report indicates that without such extensions 40% of the nuclear fleet in developed economies may be retired within a decade, adding around US$ 80 billion per year to electricity bills. The IEA note the potential for nuclear plant maintenance and extension programmes to support recovery measures by generating significant economic activity and employment.

The need for flexibility

New nuclear power projects can provide similar economic and environmental benefits and applications beyond electricity, but will be all the more challenging to finance without strong policy support and more substantive power market reforms, including improved frameworks for remunerating reliability, flexibility and other services. The need for flexibility in electricity generation and system operation - a trend accelerated by the crisis - will increasingly characterize future energy systems over the medium to longer term.

Looking further ahead, while generators and system operators successfully responded to the crisis, the observed decline in fossil fuel generation draws attention to additional grid stability challenges likely to emerge further into the energy transition. Heavy rotating steam and gas turbines provide mechanical inertia to an electricity system, thereby maintaining its balance. Replacing these capacities with variable renewables may result in greater instability, poorer power quality and increased incidence of blackouts. Large nuclear power plants along with other technologies can fill this role, alleviating the risk of supply disruptions in fully decarbonized electricity systems.

The challenges created by COVID-19 have also brought into focus the need to ensure resilience is built-in to future energy systems to cope with a broader range of external shocks, including more variable and extreme weather patterns expected from climate change.

The performance of nuclear power during the crisis provides a timely reminder of its ongoing contribution and future potential in creating a more sustainable, reliable, low carbon energy system.

Data sources for electricity demand, generation and prices: European Network of Transmission System Operators for Electricity (Europe), Ukrenergo National Power Company (Ukraine), Power System Operation Corporation (India), Korea Power Exchange (South Korea), Operador Nacional do Sistema Eletrico (Brazil), Independent Electricity System Operator (Ontario, Canada), EIA (USA). Data cover 1 January to May/June.

 

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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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Cape Town to Build Own Power Plants, Buy Additional Electricity

Cape Town Renewable Energy Plan targets 450+ MW via solar, wind, and battery storage, cutting Eskom reliance, lowering greenhouse gas emissions, stabilizing electricity prices, and boosting grid resilience through municipal procurement, PPAs, and city-owned plants.

 

Key Points

A municipal plan to procure over 450 MW, cut Eskom reliance, stabilize prices, and reduce Cape Town emissions.

✅ Up to 150 MW from private plants within the city

✅ 300 MW to be purchased from outside Cape Town later

✅ City financing 100-200 MW of its own generation

 

Cape Town is seeking to secure more than 450 megawatts of power from renewable sources to cut reliance on state power utility Eskom Holdings SOC Ltd., where wind procurement cuts were considered during lockdown, and reduce greenhouse gas emissions.

South Africa’s second-biggest city is looking at a range of options, including geothermal exploration in comparable markets, and expects the bulk of the electricity to be generated from solar plants, Kadri Nassiep, the city’s executive director of energy and climate change, said in an interview.

On July 14 the city of 4.6 million people released a request for information to seek funding to build its own plants. This month or next it will seek proposals for the provision of as much as 150 megawatts from privately owned plants, largely solar additions, to be built and operated within the city, he said. As much as 300 megawatts may also be purchased at a later stage from plants outside of Cape Town, according to Nassiep.

The city could secure finance to build 100 to 200 megawatts of its own generation capacity, Nassiep said. “We realized that it is important for the city to be more in control around the pricing of the power,” he added.

Power Outages

Cape Town’s foray into the securing of power from sources other than Eskom comes after more than a decade of intermittent electricity outages, while elsewhere in Africa coal projects face scrutiny from lenders, because the utility can’t meet national demand. The government last year said municipalities could find alternative suppliers.

Earlier this month Ethekwini, the municipal area that includes the city of Durban, issued a request for information for the provision of 400 megawatts of power, similar to BC Hydro’s call for power driven by EV uptake.

The City of Johannesburg will in September seek information and proposals for the construction of a 150-megawatt solar plant, reflecting moves like Ontario’s new wind and solar procurements to tackle supply gaps, 50 megawatts of rooftop solar panels and the refurbishment of an idle gas-fired plant that could generate 20 megawatts, it said in June. It will also seek information for the installation of 100 megawatts of battery storage.

Cape Town, which uses a peak of 1,800 megawatts of electricity in winter, hopes to start generating some of its own power next year, aligning with SaskPower’s 2030 renewables plan seen in Canada, according to a statement that accompanied its request for financing proposals.
 

 

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BC Hydro activates "winter payment plan"

BC Hydro Winter Payment Plan lets customers spread electricity bills over six months during cold weather, easing costs amid colder-than-average temperatures in British Columbia, with low-income conservation support, energy-saving kits, and insulation upgrades.

 

Key Points

Allows BC Hydro customers to spread winter electricity bills over six months, with added low-income efficiency support.

✅ Spread Dec-Mar bills across six months

✅ Eases costs during colder-than-average temperatures

✅ Includes low-income conservation and energy-saving kits

 

As colder temperatures set in across the province again this weekend, BC Hydro says it is activating its winter payment plan to give customers the opportunity to spread out their electricity bills as demand can reach record levels during extreme cold periods.

"Our meteorologists are predicting colder-than-average temperatures will continue over the next of couple of months and we want to provide customers with help to manage their payments," said Chris O'Riley, BC Hydro's president.

All BC Hydro customers will be able to spread payments from the billing period spanning Dec. 1, 2017 to March 31, 2018 over a six-month period.

Cold weather in the second half of December 2017 led to surging electricity demand that was higher than the previous 10-year average and has at times hit all-time highs during peak usage periods, according to BC Hydro.

Hydro operations also respond to summer conditions, as drought and low rainfall can force adjustments in power generation strategies.

People who heat their homes with electricity — about 40 per cent of British Columbians —  have the highest overall bills in the province, $197 more in December than in July, when air conditioning use can affect energy costs.

This is the second year the Crown corporation has activated a cold-weather payment plan, part of broader customer assistance programs it offers.  

BC Hydro has also increased funding for its low-income conservation programs by $2.2 million for a total of $10 million over the next three years. 

The low-income program provides energy-saving kits that include things like free energy assessments, insulation upgrades and weather stripping. 

 

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Which of the cleaner states imports dirty electricity?

Hourly Electricity Emissions Tracking maps grid balancing areas, embodied emissions, and imports/exports, revealing carbon intensity shifts across PJM, ERCOT, and California ISO, and clarifying renewable energy versus coal impacts on health and climate.

 

Key Points

An hourly method tracing generation, flows, and embodied emissions to quantify carbon intensity across US balancing areas.

✅ Hourly traces of imports/exports and generation mix

✅ Consumption-based carbon intensity by balancing area

✅ Policy insights for renewables, coal, health costs

 

In the United States, electricity generation accounts for nearly 30% of our carbon emissions. Some states have responded to that by setting aggressive renewable energy standards; others are hoping to see coal propped up even as its economics get worse. Complicating matters further is the fact that many regional grids are integrated, and as America goes electric the stakes grow, meaning power generated in one location may be exported and used in a different state entirely.

Tracking these electricity exports is critical for understanding how to lower our national carbon emissions. In addition, power from a dirty source like coal has health and environment impacts where it's produced, and the costs of these aren't always paid by the parties using the electricity. Unfortunately, getting reliable figures on how electricity is produced and where it's used is challenging, even for consumers trying to find where their electricity comes from in the first place, leaving some of the best estimates with a time resolution of only a month.

Now, three Stanford researchers—Jacques A. de Chalendar, John Taggart, and Sally M. Benson—have greatly improved on that standard, and they have managed to track power generation and use on an hourly basis. The researchers found that, of the 66 grid balancing areas within the United States, only three have carbon emissions equivalent to our national average, and they have found that imports and exports of electricity have both seasonal and daily changes. de Chalendar et al. discovered that the net results can be substantial, with imported electricity increasing California's emissions/power by 20%.

Hour by hour
To figure out the US energy trading landscape, the researchers obtained 2016 data for grid features called balancing areas. The continental US has 66 of these, providing much better spatial resolution on the data than the larger grid subdivisions. This doesn't cover everything—several balancing areas in Canada and Mexico are tied in to the US grid—and some of these balancing areas are much larger than others. The PJM grid, serving Pennsylvania, New Jersey, and Maryland, for example, is more than twice as large as Texas' ERCOT, in a state that produces and consumes the most electricity in the US.

Despite these limitations, it's possible to get hourly figures on how much electricity was generated, what was used to produce it, and whether it was used locally or exported to another balancing area. Information on the generating sources allowed the researchers to attach an emissions figure to each unit of electricity produced. Coal, for example, produces double the emissions of natural gas, which in turn produces more than an order of magnitude more carbon dioxide than the manufacturing of solar, wind, or hydro facilities. These figures were turned into what the authors call "embodied emissions" that can be traced to where they're eventually used.

Similar figures were also generated for sulfur dioxide and nitrogen oxides. Released by the burning of fossil fuels, these can both influence the global climate and produce local health problems.

Huge variation
The results were striking. "The consumption-based carbon intensity of electricity varies by almost an order of magnitude across the different regions in the US electricity system," the authors conclude. The low is the Bonneville Power grid region, which is largely supplied by hydropower; it has typical emissions below 100kg of carbon dioxide per megawatt-hour. The highest emissions come in the Ohio Valley Electric region, where emissions clear 900kg/MW-hr. Only three regional grids match the overall grid emissions intensity, although that includes the very large PJM (where capacity auction payouts recently fell), ERCOT, and Southern Co balancing areas.

Most of the low-emissions power that's exported comes from the Pacific Northwest's abundant hydropower, while the Rocky Mountains area exports electricity with the highest associated emissions. That leads to some striking asymmetries. Local generation in the hydro-rich Idaho Power Company has embodied emissions of only 71kg/MW-hr, while its imports, coming primarily from Rocky Mountain states, have a carbon content of 625kg/MW-hr.

The reliance on hydropower also makes the asymmetry seasonal. Local generation is highest in the spring as snow melts, but imports become a larger source outside this time of year. As solar and wind can also have pronounced seasonal shifts, similar changes will likely be seen as these become larger contributors to many of these regional grids. Similar things occur daily, as both demand and solar production (and, to a lesser extent, wind) have distinct daily profiles.

The Golden State
California's CISO provides another instructive case. Imports represent less than 30% of its total electric use in 2016, yet California electricity imports provided 40% of its embodied emissions. Some of these, however, come internally from California, provided by the Los Angeles Department of Water and Power. The state itself, however, has only had limited tracking of imported emissions, lumping many of its sources as "other," and has been exporting its energy policies to Western states in ways that shape regional markets.

Overall, the 2016 inventory provides a narrow picture of the US grid, as plenty of trends are rapidly changing our country's emissions profile, including the rise of renewables and the widespread adoption of efficiency measures and other utility trends in 2017 that continue to evolve. The method developed here can, however, allow for annual updates, providing us with a much better picture of trends. That could be quite valuable to track things like how the rapid rise in solar power is altering the daily production of clean power.

More significantly, it provides a basis for more informed policymaking. States that wish to promote low-emissions power can use the information here to either alter the source of their imports or to encourage the sites where they're produced to adopt more renewable power. And those states that are exporting electricity produced primarily through fossil fuels could ensure that the locations where the power is used pay a price that includes the health costs of its production.

 

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