EPRI, Entergy validate voltage stability monitoring

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The Electric Power Research Institute (EPRI) and Entergy Corporation (Entergy) have validated a method developed by EPRI for continuously calculating the voltage stability margin on transmission networks using measured voltage and current waveforms at the transmission substation level.

The method promises to overcome limitations of traditional methods that rely primarily on simulation-based methods and promises to help power system operators prevent voltage collapse.

The offline validation was conducted on the western region of EntergyÂ’s power system and demonstrated how voltage instability margins can be calculated in real time using data from selected transmission substations. The calculated voltage stability margins provide important indices for power system operators to monitor and control voltage stability.

“It is extremely challenging to assess voltage stability in a continuously changing electric system,” said Sharma Kolluri, manager, transmission planning at Entergy. “Utilities and system operators need dependable tools to accurately predict voltage stability margins in order to come up with mitigation plans.”

Voltage stability assessment (VSA) is important in helping power system operators anticipate potential system-wide instability problems. Although computer simulation tools are available to help monitor and control system voltage stability, their accuracy depends primarily on computer modeling of generation, load, and transmission facilities.

“As transmission networks operate closer to their limits, maintaining voltage stability is more important than ever,” said Arshad Mansoor, vice president for power delivery and utilization at EPRI. “During conditions of high transmission loading or a power system disturbance, progressive drops in voltage can jeopardize system integrity. If the voltage drops were not corrected, voltage instability could lead to voltage collapse and wide-area blackouts. Having the capability to assess the stability margins online is an important step in improving reliability.”

“The results of the validation study have shown us here at Entergy that this is promising for enhancing the security of our transmission system,” says Sujit Mandal, senior staff engineer at Entergy.

Mansoor also said that this research has established a solid technical foundation for the next steps in the technology’s development — demonstration and validation at the control center level and implementation as an online tool.

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Clorox accelerates goal of achieving 100% renewable electricity in the U.S. and Canada to 2021

Clorox Enel 70 MW VPPA accelerates renewable energy, sourcing Texas solar from the Roadrunner project to support 100% renewable electricity, Scope 2 reductions, and grid decarbonization through a virtual power purchase agreement starting in 2021.

 

Key Points

A 12-year virtual power purchase agreement for 70 MW of Texas solar to advance Clorox's 100% renewable electricity goal.

✅ 12-year contract supporting 100% renewable electricity by 2021

✅ Supplies 70 MW from Enel's Roadrunner solar project in Texas

✅ Cuts Scope 2 emissions via grid-delivered virtual PPA

 

The Clorox Company and a wholly owned subsidiary of Enel Green Power North America announced today the signing of a 12-year, 70 megawatt (MW) virtual power purchase agreement (VPPA) for the purchase of renewable energy, aligned with carbon-free electricity investments across the power sector beginning in 2021. Representing about half of Clorox's 100% renewable electricity goal in its operations in the U.S. and Canada, this agreement is expected to help Clorox accelerate achieving its goal in 2021, four years ahead of the company's original plan.

"Climate change and rising greenhouse gas emissions pose a real threat to the health of our planet and ultimately the long-term well-being of people globally. That's why we've taken action for more than 10 years to measure and reduce the carbon footprint of our operations," said Benno Dorer, chair and CEO, The Clorox Company. "Our agreement with Enel helps to expand U.S. renewable energy infrastructure, reflecting our view that companies like Clorox play an important role in addressing global climate change, as landmark policies like the U.S. climate deal further accelerate the transition. We believe this agreement will significantly contribute toward Clorox achieving our goal of 100% renewable electricity in our operations in the U.S. and Canada in 2021, four years earlier than originally planned. Our commitment to climate stewardship is an important pillar of our new IGNITE strategy and part of our overall efforts to drive Good Growth – growth that's profitable, sustainable and responsible."

The 70MW VPPA between Clorox and Enel Green Power North America for the purchase of renewable energy delivered to the electricity grid is for the second phase of Enel's Roadrunner solar project to be built in Texas, and complement global clean energy collaborations such as Canada-Germany hydrogen cooperation announced recently. Roadrunner is a 497-direct current megawatt (MWdc) solar project that is being built in two phases. The first phase, currently under construction, comprises around 252 MWdc and is expected to be completed by the end of 2019, while the remaining 245 MWdc of capacity is expected to be completed by the end of 2020. Once fully operational, the solar plant could generate up to 1.2 terawatt-hours (TWh) of electricity annually, while avoiding an estimated 800,000 metric tons of carbon dioxide emissions per year.

Based on the U.S. Environmental Protection Agency Greenhouse Gas Equivalencies Calculator[i], this VPPA is estimated to avoid approximately 140,000 metric tons of CO2 emissions each year. This is equivalent to the annual impact that 165,000 acres of U.S. forest can have in removing CO2 from the atmosphere, and illustrates why cleaning up Canada's electricity is central to emissions reductions in the power sector, or the carbon impact of the electricity needed to power more than 24,000 U.S. homes annually.

"We are proud to support Clorox on their path towards 100% renewable electricity in its operations in the U.S. and Canada by helping them achieve about half their goal through this agreement," said Georgios Papadimitriou, head of Enel Green Power North America. "This agreement with Clorox reinforces the continued significance of renewable energy as a fundamental part of any company's sustainability strategy."

Schneider Electric Energy & Sustainability Services advised Clorox on this power purchase agreement and, amid heightened investor attention exemplified by the Duke Energy climate report, supported the company in its project selection, analysis, negotiations and deal execution.

 

Clorox Commits to Scope 1, 2 and 3 Science-Based Targets

For more than 10 years, Clorox has consistently achieved its goals to reduce greenhouse gas emissions in its operations. Clorox is focused on setting emissions reduction targets in line with climate science. As a participant in the Science Based Targets Initiative, Clorox has committed to setting and achieving science-based greenhouse gas emissions reduction targets in its operations (Scopes 1 and 2) and across its value chain (Scope 3), and consistent with national pathways such as Canada's net-zero 2050 target pursued by policymakers. The targets are considered "science-based" if they are in line with what the latest climate science says is necessary to meet the goals of the 2015 Paris Agreement – a global environmental accord to address climate change and its negative impacts.

Clorox's climate stewardship goals are part of its new integrated corporate strategy called IGNITE, which includes several other environmental, social and governance (ESG) goals and reflects lessons from Canada's electricity progress in scaling clean power. More comprehensive information about Clorox's IGNITE ESG goals can be found here. Information on Clorox's 2020 ESG strategy can be found in its fiscal year 2019 annual report.

 

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International Atomic Energy Agency agency commends China's nuclear security

IAEA Nuclear Security Mission in China reviews regulatory frameworks, physical protection, and compliance at nuclear power plants, endorsing CAEA efforts, IPPAS guidance, and capacity building to strengthen safeguards, risk management, and global cooperation.

 

Key Points

An IAEA advisory visit assessing China's nuclear security, physical protection, and regulatory frameworks.

✅ Reviews laws, regulations, and physical protection measures

✅ Endorses CAEA, COE, and IPPAS-aligned best practices

✅ Recommends accelerated rulemaking for expanding reactors

 

The International Atomic Energy Agency commended China's efforts and accomplishments in nuclear security after conducting its first nuclear security advisory mission to the nation, according to the China Atomic Energy Authority.

The two-week International Physical Protection Advisory Service mission, from Aug 28to Saturday, reviewed the legislative and regulatory framework for nuclear security as well as the physical protection of nuclear material and facilities, including worker safety protocols during health emergencies.

An eight-member expert team led by Joseph Sandoval of the United States' Sandia National Laboratories visited Fangjiashan Nuclear Power Plant, part of the Qinshan Nuclear Power Station in Zhejiang province, to examine security arrangements and observe physical protection measures, where recognized safety culture practices can reinforce performance.

The experts also met with officials from several Chinese government bodies involved in nuclear security such as the China Atomic Energy Authority, National Nuclear Safety Administration and Ministry of Public Security.

The international agency has carried out 78 of the protection missions in 48 member states since 1995. This was the first in China, it said.

The China Atomic Energy Authority said on Tuesday that a report by the experts highly approves of the Chinese government's continuous efforts to strengthen nuclear safety, to boost the sustainable development of the nuclear power industry and to help establish a global nuclear security system.

The report identifies the positive roles played by the State Nuclear Security Technology Center and its subsidiary, the Center of Excellence on Nuclear Security, in enhancing China's nuclear security capability and supporting regional and global cooperation in the field, such as bilateral cooperation agreements that advance research and standards, officials at the China Atomic Energy Authority said.

"A strong commitment to nuclear security is a must for any state that uses nuclear power for electricity generation and that is planning to significantly expand this capacity by constructing new power reactors," said Muhammad Khaliq, head of the international agency's nuclear security of materials and facilities section. "China'sexample in applying IAEA nuclear security guidance and using IAEA advisory services demonstrates its strong commitment to nuclear security and its enhancement worldwide."

The report notes that along with the rapid growth of China's nuclear power sector, challenges have emerged when it comes to the country's nuclear security mechanism and management, as highlighted by grid reliability warnings during pandemics in other markets.

It suggests that the Chinese government accelerate the making of laws and regulations to better govern this sector.

Deng Ge, director of the State Nuclear Security Technology Center, said the IAEAmission would help China strengthen its nuclear security since the nation could learn from other countries' successful experience, including on-site staffing measures to maintain critical operations, and find out its weaknesses for rectification.

Deng added that the mission's report can help the international community understand China's contributions to the global nuclear security system and also offer China's best practices to other nations.

 

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U.S. Residents Averaged Fewer Power Outages in 2022

2022 U.S. Power Outage Statistics show lower SAIDI as fewer major events hit, with SAIFI trends, electric reliability, outage duration and frequency shaped by hurricanes, winter storms, vegetation, and utility practices across states.

 

Key Points

They report SAIDI and SAIFI for 2022, showing outage duration, frequency, and impacts of major weather events.

✅ 2022 SAIDI averaged 5.6 hours; SAIFI averaged 1.4 interruptions.

✅ Fewer major events lowered outage duration versus 2021.

✅ Hurricanes and winter storms drove long outages in several states.

 

In 2022, U.S. electricity consumers on average experienced about 5.5 hours of power disruptions, a decrease from nearly two hours compared to 2021. This information comes from the latest Annual Electric Power Industry Report. The reduction in yearly power interruptions primarily resulted from fewer significant events in 2022 compared to the previous year, and utility disaster planning continues to support grid resilience as severe weather persists.

Since 2013, excluding major events, the annual average duration of power interruptions has consistently hovered around two hours. Factors contributing to major power disruptions include weather-related incidents, vegetation interference near power lines, and specific utility practices, while pandemic-related grid operations influenced workforce planning more than outage frequency. To assess the reliability of U.S. electric utilities, two key indexes are utilized:

  • The System Average Interruption Duration Index (SAIDI) calculates the total length (in hours) an average customer endures non-brief power interruptions over a year.
  • The System Average Interruption Frequency Index (SAIFI) tracks the number of times interruptions occur.

The influence of major events on electrical reliability is gauged by comparing affected states' SAIDI and SAIFI values against the U.S. average, which was 5.6 hours of outages and 1.4 outages per customer in 2022. The year witnessed 18 weather-related disasters in the U.S., each resulting in over $1 billion in damages, and COVID-19 grid assessments indicated the electricity system was largely safe from pandemic impacts. Noteworthy major events include:

  • Hurricane Ian in September 2022, leaving over 2.6 million Floridian customers without electricity, with restoration in some areas taking weeks rather than days.
  • Hurricane Nicole in November 2022, causing over 300,000 Florida customers to lose power.
  • Winter Storm Elliott in December 2022, affecting over 1.5 million customers in multiple states including Texas where utilities struggled after Hurricane Harvey to restore service, and Florida, and bringing up to four feet of snow in parts of New York.

In 2022, states like Florida, West Virginia, Maine, Vermont, and New Hampshire experienced the most prolonged power interruptions, with New Hampshire averaging 10.3 hours and Florida 19.1 hours, and FPL's Irma storm response illustrates how restoration can take days or weeks in severe cases. Conversely, the District of Columbia, Delaware, Rhode Island, Nebraska, and Iowa had the shortest total interruptions, with the District of Columbia averaging just 34 minutes and Iowa 85 minutes.

The frequency of outages, unlike their duration, is more often linked to non-major events. Across the nation, Alaska recorded the highest number of power disruptions per customer (averaging 3.5), followed by several heavily forested states like Tennessee and Maine. Power outages due to falling tree branches are common, particularly during winter storms that burden tree limbs and power lines, as seen in a North Seattle outage affecting 13,000 customers. The District of Columbia stood out with the shortest and fewest outages per customer.

 

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TransAlta Scraps Wind Farm as Alberta's Energy Future Blusters

Alberta Wind Energy Policy Changes highlight TransAlta's Riplinger cancellation amid UCP buffer zones for pristine viewscapes, regulatory uncertainty, and market redesign debates, reshaping Alberta's renewables investment climate and clean energy diversification plans.

 

Key Points

UCP rules and market shifts reshaping wind siting, permits, and finance, increasing uncertainty and delays for new projects.

✅ 35-km buffer near pristine viewscapes limits wind siting

✅ TransAlta cancels 300 MW Riplinger project

✅ Market redesign uncertainty chills renewables investment

 

The winds of change are blowing through Alberta's energy landscape today, and they're not necessarily carrying good news for renewable energy development. TransAlta, a major Canadian energy company, recently announced the cancellation of a significant wind farm project, citing a confluence of factors that create uncertainty for the future of wind power in the province. This decision throws a spotlight on the ongoing debate between responsible development and fostering a clean energy future in Alberta.

The scrapped project, the Riplinger wind farm near Cardston, Alberta, was envisioned as a 300-megawatt facility capable of providing clean electricity to the province. However, TransAlta pointed to recent regulatory changes implemented by the United Conservative Party (UCP) government, following the end of the renewable energy moratorium in Alberta, as a key reason for the project's demise. These changes include the establishment of a 35-kilometer buffer zone around designated "pristine viewscapes," which significantly restricts potential wind farm locations.

John Kousinioris, CEO of TransAlta, expressed frustration with the lack of clarity surrounding the future of renewable energy policy in Alberta. He highlighted this, along with the aforementioned rule changes, as major factors in the project's cancellation. TransAlta has also placed three other power projects on hold, indicating a broader concern about the current investment climate for renewable energy in the province.

The news has been met with mixed reactions. While some residents living near the proposed wind farm site celebrate the decision due to concerns about potential impacts on tourism and the environment, others worry about the implications for Alberta's clean energy ambitions, including renewable energy job growth in the province. The province, a major energy producer in Canada, has traditionally relied heavily on fossil fuels, and this decision might be seen as a setback for its goals of diversifying its energy mix.

The Alberta government defends its changes to renewable energy policy, arguing that they are necessary to ensure responsible development and protect sensitive ecological areas. However, the TransAlta decision raises questions about the potential unintended consequences of these changes. Critics argue that the restrictions might discourage investment in renewable energy and the province's ability to sell clean power to wider markets altogether, hindering Alberta's progress towards a more sustainable future.

Adding to the uncertainty is the ongoing process of redesigning Alberta's energy market. The aim is to incorporate more renewable energy sources, including solar energy expansion across the grid, but the details of this redesign remain unclear. This lack of transparency makes it difficult for companies like TransAlta to make sound investment decisions, further dampening enthusiasm for renewable energy projects.

The future of wind energy development in Alberta remains to be seen. TransAlta's decision to scrap the Riplinger project is a significant development, and it will be interesting to observe how other companies respond to the changing regulatory landscape, as a Warren Buffett-linked developer pursues a $200 million wind project in Alberta. Striking a balance between responsible development, protecting the environment, and fostering a clean energy future will be a crucial challenge for Alberta moving forward.

This situation highlights the complex considerations involved in transitioning to a renewable energy future, where court rulings on wind projects can influence policy and investment decisions. While environmental concerns are paramount, ensuring a stable and predictable investment climate is equally important. Open communication and collaboration between industry, government, and stakeholders will be key to navigating these challenges and ensuring Alberta can harness the power of wind energy for a sustainable future.

 

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Hydro One delivery rates go up

Hydro One Rate Hike reflects Ontario Energy Board approval for higher delivery charges, impacting seasonal customers more than residential classes, funding infrastructure upgrades like wood pole and transformer replacements across Ontario's medium-density service areas.

 

Key Points

The Hydro One rate hike is an OEB-approved delivery charge increase to fund upgrades, with impacts on seasonal users.

✅ OEB-approved delivery rate increases retroactive to 2018

✅ Seasonal customers see larger monthly bill impacts than residential

✅ Funds pole, transformer replacements and tree trimming work

 

Hydro One seasonal customers will face bigger increases in their bills than the utility's residential customers as a result of an Ontario Energy Board approval of a rate hike, a topic drawing attention from a utilities watchdog in other provinces as well.

Hydro One received permission to increase its delivery charge, as large projects like the Meaford hydro generation proposal are considered across Ontario, retroactive to last year.

It says it needs the money to maintain and upgrade its infrastructure, including efforts to adapt to climate change, much of which was installed in the 1950s.

The utility is notifying customers that new statements reflect higher delivery rates which were not charged in 2018 and the first half of this year, due to delay in receiving the OEB's permission, similar to delays that can follow an energy board recommendation in other jurisdictions.

The amount that customers' bills will increase by depends not only on how much electricity they use, but also on which rate class they belong to, as well as policy decisions affecting remote connections such as the First Nations electricity line in northern Ontario.

For seasonal customers such as summer cottage owners, the impact on a typical user's bill will be 2.9 per cent more per month for 2018, and 1.7 per cent per month for 2019.

There will be further increases of 1.0 per cent, 1.4 per cent and 1.1 per cent per month in 2020, 2021 and 2022 respectively. 

Typical residential customers will experience smaller increases or rate freezes over the same period.

In the residential medium density class, the rate changes are a 2.0 per cent increase for last year, a decrease of 0.5 per cent this year, and an increase of 0.5 per cent in 2021. There will be no increases in 2020 and 2022.

 

Seasonal Rate Class — Estimated bill impact per month

2018 - 2.9 %

2019 - 1.7%

2020 - 1.0%

2021 - 1.4%

2022 - 1.1%

 

Residential Medium Density Rate Class — Estimated bill impact per month

2018 - 2.0%

2019 - -0.5% decrease

2020 - 0.0%

2021 - 0.5%

2022 - 0.0%

A Hydro One spokesperson told tbnewswatch.com that over the next three years, the utility's upgrading plan includes reliability investments such as replacing more than 24,000 wood poles across the province as well as numerous transformers.

In the Thunder Bay area, the spokesperson said, some of the revenue generated by the higher delivery rates will cover the cost of replacing more than 180 poles and trimming hazardous trees around 3,200 kilometres of overhead power lines while sharing electrical safety tips with customers.

 

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N.S. approves new attempt to harness Bay of Fundy's powerful tides

Bay of Fundy Tidal Energy advances as Nova Scotia permits Jupiter Hydro to test floating barge platforms with helical turbines in Minas Passage, supporting renewable power, grid-ready pilots, and green jobs in rural communities.

 

Key Points

A Nova Scotia tidal energy project using helical turbines to generate clean power and create local jobs.

✅ Permits enable 1-2 MW prototypes near Minas Passage

✅ Floating barge platforms with patented helical turbines

✅ PPA at $0.50/kWh with Nova Scotia Power

 

An Alberta-based company has been granted permission to try to harness electricity from the powerful tides of the Bay of Fundy.

Nova Scotia has issued two renewable energy permits to Jupiter Hydro.

Backers have long touted the massive energy potential of Fundy's tides -- they are among the world's most powerful -- but large-scale commercial efforts to harness them have borne little fruit so far, even as a Scottish tidal project recently generated enough power to supply nearly 4,000 homes elsewhere.

The Jupiter application says it will use three "floating barge type platforms" carrying its patented technology. The company says it uses helical turbines mounted as if they were outboard motors.

"Having another company test their technology in the Bay of Fundy shows that this early-stage industry continues to grow and create green jobs in our rural communities," Energy and Mines Minister Derek Mombourquette said in a statement.

The first permit allows the company to test a one-megawatt prototype that is not connected to the electricity grid.

The second -- a five-year permit for up to two megawatts -- is renewable if the company meets performance standards, environmental requirements and community engagement conditions.

Mombourquette also authorized a power purchase agreement that allows the company to sell the electricity it generates to the Nova Scotia grid through Nova Scotia Power for 50 cents per kilowatt hour.

On its web site, Jupiter says it believes its approach "will prove to be the most cost effective marine energy conversion technology in the world," even as other regional utilities consider initiatives like NB Power's Belledune concept for turning seawater into electricity.

The one megawatt unit would have screws which are about 5.5 metres in diameter.

The project is required to obtain all other necessary approvals, permits and authorizations.

It will be located near the Fundy Ocean Research Center for Energy in the Minas Passage and will use existing electricity grid connections.

A study commissioned by the Offshore Energy Research Association of Nova Scotia says by 2040, the tidal energy industry could contribute up to $1.7 billion to Nova Scotia's gross domestic product and create up to 22,000 full-time jobs, a transition that some argue should be planned by an independent body to ensure reliability.

Last month, Nova Scotia Power said it now generates 30 per cent of its power from renewables, as the province moves to increase wind and solar projects after abandoning the Atlantic Loop.

The utility says 18 per cent came from wind turbines, nine per cent from hydroelectric and tidal turbines and three per cent by burning biomass across its fleet.

However, over half of the province's electrical generation still comes from the burning of coal or petroleum coke, even as environmental advocates push to reduce biomass use in the mix. Another 13 per cent come from burning natural gas and five per cent from imports.

 

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