EPRI, Entergy validate voltage stability monitoring

By Electricity Forum


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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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U.S. Speeds Up Permitting for Geothermal Energy

Geothermal Emergency Permitting accelerates BLM approvals on public lands via categorical exclusions for exploratory drilling and geophysical surveys, boosting domestic energy security, cutting timelines by up to a year, and streamlining low-impact reviews.

 

Key Points

A policy fast-tracking geothermal exploration on public lands, using BLM categorical exclusions to cut review delays.

✅ Categorical exclusions speed exploratory drilling approvals

✅ Cuts permitting timelines by up to one year

✅ Focused on public lands to enhance energy security

 

In a significant policy shift, the U.S. Department of the Interior has introduced emergency permitting procedures aimed at expediting the development of geothermal energy projects. This initiative, announced on May 30, 2025, is part of a broader strategy to enhance domestic energy production, seen in proposals to replace Obama's power plant overhaul and reduce reliance on foreign energy sources.

Background and Rationale

The decision to fast-track geothermal energy projects comes in the wake of President Donald Trump's declaration of a national energy emergency, which faces a legal challenge from Washington's attorney general, on January 20, 2025. This declaration cited high energy costs and an unreliable energy grid as threats to national security and economic prosperity. While the emergency order includes traditional energy resources such as oil, gas, coal, and uranium and nuclear energy resources, it notably excludes renewable sources like solar, wind, and hydrogen from its scope.

Geothermal energy, which harnesses heat from beneath the Earth's surface to generate electricity, is considered a reliable and low-emission energy source. However, its development has been hindered by lengthy permitting processes and environmental reviews, with recent NEPA rule changes influencing timelines. The new emergency permitting procedures aim to address these challenges by streamlining the approval process for geothermal projects.

Key Features of the Emergency Permitting Procedures

Under the new guidelines, the Bureau of Land Management (BLM) has adopted categorical exclusions to expedite the review and approval of geothermal energy exploration on public lands. These exclusions allow for faster permitting of low-impact activities, such as drilling exploratory wells and conducting geophysical surveys, without the need for extensive environmental assessments.

Additionally, the BLM has proposed a new categorical exclusion that would apply to operations related to the search for indirect evidence of geothermal resources. This proposal is currently open for public comment and, if finalized, would further accelerate the discovery of new geothermal resources on public lands.

Expected Impact on Geothermal Energy Development

The implementation of these emergency permitting procedures is expected to significantly reduce the time and cost associated with developing geothermal energy projects. According to the Department of the Interior, the new measures could cut permitting timelines by up to a year for certain types of geothermal exploration activities.

This acceleration in project development is particularly important given the untapped geothermal potential in regions like Nevada, which is home to some of the largest undeveloped geothermal resources in the country.

Industry and Environmental Reactions

The geothermal industry has largely welcomed the new permitting procedures, viewing them as a necessary step to unlock the full potential of geothermal energy. Industry advocates argue that reducing permitting delays will facilitate the deployment of geothermal projects, contributing to a more reliable and sustainable energy grid amid debates over electricity pricing changes that affect market signals.

However, the exclusion of solar and wind energy projects from the emergency permitting procedures has drawn criticism from some environmental groups. Critics argue that a comprehensive approach to energy development should include all renewable sources, not just geothermal, to effectively address climate change, as reflected in new EPA pollution limits for coal and gas power plants, and promote energy sustainability.

The U.S. government's move to implement emergency permitting procedures for geothermal energy development marks a significant step toward enhancing domestic energy production and reducing reliance on foreign energy sources. By streamlining the approval process for geothermal projects, the administration aims to accelerate the deployment of this reliable and low-emission energy source. While the exclusion of other renewable energy sources from the emergency procedures has sparked debate, especially after states like California halted an energy rebate program during a federal freeze, the focus on geothermal energy underscores its potential role in the nation's energy future.

 

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Bangladesh develops nuclear power with IAEA Assistance

Bangladesh Rooppur Nuclear Power Plant advances nuclear energy with IAEA support and ROSATOM construction, boosting energy security, baseload capacity, and grid reliability; 2400 MW units aid development, regulatory compliance, and newcomer infrastructure milestones.

 

Key Points

A 2400 MW nuclear project in Rooppur, built with IAEA guidance and ROSATOM, to boost Bangladesh's reliable power.

✅ Two units totaling 2400 MW for stable baseload supply

✅ IAEA Milestones and INIR reviews guide safe deployment

✅ ROSATOM builds; national regulator strengthens oversight

 

The beginning of construction at Bangladesh’s first nuclear power reactor on 30 November 2017 marked a significant milestone in the decade-long process to bring the benefits of nuclear energy to the world’s eighth most populous country. The IAEA has been supporting Bangladesh on its way to becoming the third ‘newcomer’ country to nuclear power in 30 years, following the United Arab Emirates in 2012 and Belarus in 2013.

Bangladesh is in the process of implementing an ambitious, multifaceted development programme to become a middle-income country by 2021 and a developed country by 2041. Vastly increased electricity production, with the goal of connecting 2.7 million more homes to the grid by 2021, is a cornerstone of this push for development, and nuclear energy will play a key role in this area, said Mohammad Shawkat Akbar, Managing Director of Nuclear Power Plant Company Bangladesh Limited. Bangladesh is also working to diversify its energy supply to enhance energy security, reduce its dependence on imports and on its limited domestic resources, he added.

#google# In the region, India's nuclear program is taking steps to get back on track, underscoring broader momentum.

“Bangladesh is introducing nuclear energy as a safe, environmentally friendly and economically viable source of electricity generation,” said Akbar.  The plant in Rooppur, 160 kilometres north-west of Dhaka, will consist of two units, with a combined power capacity of 2400 MW(e). It is being built by a subsidiary of Russia’s State Atomic Energy Corporation ROSATOM. The first unit is scheduled to come online in 2023 and the second in 2024, reflecting progress similar to the UK's latest nuclear power station developments.  “This project will enhance the development of the social, economic, scientific and technological potential of the country,” Akbar said.

The country’s goal of increased electricity production via nuclear energy will soon be a reality, Akbar said. “For 60 years, Bangladesh has had a dream of building its own nuclear power plant. The Rooppur Nuclear Power Plant will provide not only a stable baseload of electricity, but it will enhance our knowledge and allow us to increase our economic efficiency.

 

Milestones for nuclear

Bangladesh is among around 30 countries that are considering, planning or starting the introduction of nuclear power, with milestones at nuclear projects worldwide offering context for this progress. The IAEA assists them in developing their programmes through the Milestones Approach — a methodology that provides guidance on working towards the establishment of nuclear power in a newcomer country, including the associated infrastructure. It focuses on pointing out gaps, if any, in countries’ progress towards the introduction of nuclear power.

The IAEA has been supporting Bangladesh in developing its nuclear power infrastructure, including in establishing a regulatory framework and developing a radioactive waste-management system. This support has been delivered under the IAEA technical cooperation programme and is partially funded through the Peaceful Uses Initiative.

Nuclear infrastructure is multifaceted, containing governmental, legal, regulatory and managerial components, in addition to the physical infrastructure. The Milestones Approach consists of three phases, with a milestone to be reached at the end of each.

The first phase involves considerations before a decision is taken to start a nuclear power programme and concludes with the official commitment to the programme. The second phase entails preparatory work for the contracting and construction of a nuclear power plant, as seen in Bulgaria's nuclear project planning, ending with the commencement of bids or contract negotiations for the construction. The final phase includes activities to implement the nuclear power plant, such as the final investment decision, contracting and construction. The duration of these phases varies by country, but they typically take between 10 and 15 years.

“The IAEA Milestones Approach is a guiding document and the Integrated Work Plan (IWP) is the important means of bringing all of the stakeholders in Bangladesh together to ensure the fulfilment of all safety, security, and safeguards requirements of the Rooppur NPP project,” said Akbar. “This IWP enabled Bangladesh to develop a holistic approach to implementing IAEA guidance as well as cooperating with national stakeholders and other bilateral partners towards the development of a national nuclear power programme.”

When completed, the two units of the Rooppur Nuclear Power Plant will have a combined power capacity of 2400 MW(e). (Photo: Arkady Sukhonin/Rosatom)

 

INIR Mission

The Integrated Nuclear Infrastructure Review (INIR) is a holistic peer review to assist Member States in assessing the status of their national infrastructure for introducing nuclear power. The IAEA completed its first INIR mission to Bangladesh in November 2011, making recommendations on how to develop a plan to establish the nuclear infrastructure. Nearly five years later, in May 2016, a follow-up mission was conducted, which noted the progress made — Bangladesh had established a nuclear regulatory body, had chosen a site for the power plant and had completed site characterization and environmental impact assessment.

“The IAEA and other bodies, including those from experienced countries, can and do provide support, but the responsibility for safety and security will lie with the Government,” said Dohee Hahn, Director of the IAEA’s Division of Nuclear Power, at the ceremony for the pouring of the first nuclear safety-related concrete at Rooppur on 30 November 2017. “The IAEA stands ready to continue supporting Bangladesh in developing a safe, secure, peaceful and sustainable nuclear power programme.”

Supporting Infrastructure for Introducing a Nuclear Power Plant in Bangladesh: the IAEA Assists with the Review of Regulatory Guidance on Site Evaluation

How the IAEA Assists Newcomer Countries in Building Their Way to Sustainable Energy

"Exciting times for nuclear power," IAEA Director General Says

 

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ABO to build 10MW Tunisian solar park

ABO Wind Tunisia 10MW Solar Project will build a photovoltaic park in Gabes with a STEG PPA, fixed tariff, 2,500 m grid connection, producing 18 million kWh annually, targeted for 2020 commissioning with local partners.

 

Key Points

A 10MW photovoltaic park in Gabes with a 20-year STEG PPA and fixed tariff, slated for 2020 commissioning.

✅ 18 million kWh/year; 2,500 m grid tie, 20-year fixed tariff

✅ Electricity supplied to STEG under PPA; 2020 commissioning

✅ Located in Gabes; built with local partners, 10MW capacity

 

ABO Wind has received a permit and a tariff for a 10MW photovoltaic project in Tunisia, amid global activity such as Spain's 90MW wind project now underway, which it plans to build and commission in 2020.

The solar park, in the governorate of Gabes, is 400km south of the country’s capital Tunis and aligns with renewable funding initiatives seen across developing markets.

The developer said it plans to build the project next year in close cooperation with local partners, as regional markets from North Africa to the Gulf expand, with Saudi Arabia boosting wind capacity as well.

ABO Wind department head Nicolas Konig said: “The solar park will produce more than 18 million kilowatt hours of electricity per year and will feed it into the grid at a distance of 2500 metres.”

The developer will conclude an electricity supply contract with the state-owned energy supplier (Societe tunisienne de l’electricite et du gaz (STEG), which will provide a fixed remuneration over 20 years, a model echoed by Germany's wind-solar tender for the electricity fed into the grid.

Earlier this year, ABO Wind had already secured a tariff for a wind farm with a capacity of 30MW in a tender, 35km south-east of Tunis, underscoring Tunisia's wind investments under its long-term plan.

The company is working on half a dozen Tunisian wind and solar projects, as institutions like the World Bank support wind growth in developing countries.

“We are making good progress on our way to assemble a portfolio of several ready-to-build wind and solar projects attractive to investors, as Saudi clean energy targets continue to expand globally,” said ABO Wind general manager responsible for international business development Patrik Fischer.

 

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New Mexico Governor to Sign 100% Clean Electricity Bill ‘As Quickly As Possible’

New Mexico Energy Transition Act advances zero-carbon electricity, mandating public utilities deliver carbon-free electricity by 2045, with renewable targets of 50 percent by 2030 and 80 percent by 2040 to accelerate grid decarbonization.

 

Key Points

A state law requiring utilities to deliver carbon-free electricity by 2045, with 2030 and 2040 renewable targets.

✅ 100 percent carbon-free power from utilities by 2045

✅ Interim renewable targets: 50 percent by 2030, 80 percent by 2040

✅ Aligns with clean energy commitments in HI, CA, and DC

 

The New Mexico House of Representatives passed the Energy Transition Act Tuesday afternoon, sending the carbon-free electricity bill, a move aligned with proposals for a Clean Electricity Standard at the federal level, to Gov. Michelle Lujan Grisham.

Her opinions on it are known: she campaigned on raising the share of renewable energy, a priority echoed in many state renewable ambitions nationwide, and endorsed the ETA in a recent column.

"The governor will sign the bill as quickly as possible — we're hoping it is enrolled and engrossed and sent to her desk by Friday," spokesperson Tripp Stelnicki said in an email Tuesday afternoon.

Once signed, the legislation will commit the state to achieving zero-carbon electricity from public utilities by 2045. The bill also imposes interim renewable energy targets of 50 percent by 2030 and 80 percent by 2040, similar to Minnesota's 2040 carbon-free bill in its timeline.

The Senate passed the bill last week, 32-9. The House passed it 43-22.

The legislation would enter New Mexico into the company of Hawaii, California, where climate risks to grid reliability are shaping policy, and Washington, D.C., which have committed to eliminating carbon emissions from their grids. A dozen other states have proposed similar goals. Meanwhile, the Green New Deal resolution has prompted Congress to discuss the bigger task of decarbonizing the nation overall.

Though grid decarbonization has surged in the news cycle in recent months, even as some states consider moves in the opposite direction, such as a Wyoming bill restricting clean energy that would limit utility choices, New Mexico's bill arose from a years-long effort to rally stakeholders within the state's close-knit political community.

 

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Senate Democrats push for passage of energy-related tax incentives

Senate Renewable Energy Tax Credits face Finance Committee scrutiny, with Democrats urging action on tax extenders, clean energy incentives, and climate policy, while Republicans cite prior wins in wind, biodiesel, and EV credits.

 

Key Points

Legislative incentives debated in the Senate Finance Committee to extend and align clean energy tax benefits.

✅ Democrats press hearings and action on energy tax policy

✅ Focus on clean energy, EVs, wind, biodiesel, and resilience

✅ Grassley cites prior extenders; disputes push for bigger subsidies

 

A group of 27 Democratic senators is calling for action in the Senate Finance Committee on extending energy-related tax credits and examining new tax proposals, especially those that incentivize renewable energy projects and align with FERC action on aggregated DERs across the grid.

Sen. Ron Wyden, D-Ore., the ranking Democrat on the Senate Finance Committee, who recently introduced a wildfire-resilient grid bill with Sen. Merkley, led the group of Democrats in writing a letter Tuesday to Sen. Charles Grassley, R-Iowa, who chairs the committee.

“Despite numerous opportunities, including in the recent tax extenders package, the Finance Committee has failed to take action on the dozens of energy tax proposals pending before it,” they wrote. “It is critical that the Committee move to address these issues in a timely manner, along with much needed policy changes that heed warnings on regulatory rollbacks to combat the damage and growing dangers caused by global climate change.”

The number of Americans ages 65 and over is projected to nearly double by 2060. And most would prefer to age in place and hiresenior caregivers if needed.

They pointed out that the Senate Finance Committee hasn’t held a single hearing on energy tax policy during the previous congressional term, and has yet to hold one in the current one.

“The sole energy tax-related recommendation of the Committee’s temporary policy task forces was ignored in the tax extender legislation passed in December 2019, along with nearly all proposals put forward in members’ legislation this Congress,” they wrote. “This Committee must fulfill its role in examining members’ energy tax proposals and in bolstering our nation’s efforts to combat climate change, including a clean electricity standard approach that sets firm targets.”

They noted that In 2019, the global average temperature was the second highest ever recorded and the past decade was the hottest ever. The lawmakers pointed to raging wildfires and increased flooding in the western part of the U.S., as well as challenges in California’s power system during the transition, causing unprecedented destruction over the past several years. They called for tax incentives for renewable energy to help combat climate change.

“Gaps in the tax code have disadvantaged complementary technologies that could improve climate resiliency and provide additional emissions reductions,” they wrote. “While power sector emissions continue to decrease, emissions from transportation, heavy industry and agriculture have stayed level or increased over the past 10 years, even amid $5 gas not spurring a green shift in consumer behavior. The United States is not on pace to meet its international climate commitments, to say nothing of the reductions necessary to stave off the worst potential outcomes of global warming.”

Grassley reacted to the letter, noting that he had worked to get tax extenders legislation passed, even as some states consider bans on clean energy use by utilities. "I begged Democrats for a year to help me get an extenders package passed, about half of which were green energy policies, so this rings hollow," he said in a statement Tuesday. "We wouldn’t have a wind energy credit or a biodiesel credit but for me, let alone an extension of either. Democrats were holding up these green energy provisions in an attempt to get a big expansion of taxpayer subsidies for rich Tesla owners."

 

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Drought, lack of rain means BC Hydro must adapt power generation

BC Hydro drought operations address climate change impacts with hydropower scheduling, reservoir management, water conservation, inflow forecasting, and fish habitat protection across the Lower Mainland and Vancouver Island while maintaining electricity generation from storage facilities.

 

Key Points

BC Hydro drought operations conserve water, protect fish, and sustain hydropower during extended heat and low inflows.

✅ Proactive reservoir releases protect downstream salmon spawning.

✅ Reduced flows at Puntledge, Coquitlam, and Ruskin/Stave facilities.

✅ System relies on northern storage to maintain electricity supply.

 

BC Hydro is adjusting its operating plans around power generation as extended heat and little forecast rain continue to impact the province, a report says.

“Unpredictable weather patterns related to climate change are expected to continue in the years ahead and BC Hydro is constantly adapting to these evolving conditions, especially after events such as record demand in 2021 that tested the grid,” said the report, titled “Casting drought: How climate change is contributing to uncertain weather and how BC Hydro’s generation system is adapting.”

The study said there is no concern with BC Hydro being able to continue to deliver power through the drought because there is enough water at its larger facilities, even as issues like crypto mining electricity use draw scrutiny from observers.

Still, it said, with no meaningful precipitation in the forecast, its smaller facilities in the Lower Mainland and on Vancouver Island will continue to see record low or near record low inflows for this time of the year.

“In the Lower Mainland, inflows since the beginning of September are ranked in the bottom three compared to historical records,” the report said.

The report said the hydroelectric system is directly impacted by variations in weather and the record-setting, unseasonably dry and warm weather this fall highlights the impacts of climate change, while demand patterns can be counterintuitive, as electricity use even increased during Earth Hour 2018 in some areas, hinting at challenges to come.

It noted symptoms of climate change include increased frequency of extreme events like drought and intense storms, and rapid glacial melt.

“With the extremely hot and dry conditions, BC Hydro has been taking proactive steps at many of our South Coast facilities for months to conserve water to protect the downstream fish habit,” spokesperson Mora Scott said. “We began holding back water in July and August at some facilities anticipating the dry conditions to help ensure we would have water storage for the later summer and early fall salmon spawning.”

Scott said BC Hydro’s reservoirs play an important role in managing these difficult conditions by using storage and planning releases to provide protection to downstream river flows. The reservoirs are, in effect, a battery waiting to be used for power.

While the dry conditions have had an impact on BC Hydro’s watersheds, several unregulated natural river systems — not related to BC Hydro — have fared worse, with rivers drying up and thousands of fish killed, the report said.

BC Hydro is currently seeing the most significant impacts on operations at Puntledge and Campbell River on Vancouver Island as well as Coquitlam and Ruskin/Stave in the Lower Mainland.

To help manage water levels on Vancouver Island, BC Hydro reduced Puntledge River flows by one-third last week and on the Lower Mainland reduced flows at Coquitlam by one-third and Ruskin/Stave by one quarter.

However, the utility company said, there are no concerns about continued power delivery.

“British Columbians benefit from BC Hydro’s integrated, provincial electricity system, which helps send power across the province, including to Vancouver Island, and programs like the winter payment plan support customers during colder months,” staff said.

Most of the electricity generated and used in B.C. is produced by larger facilities in the north and southeast of the province — and while water levels in those areas are below normal levels, there is enough water to meet the province’s power needs, even as additions like Site C's electricity remain a subject of debate among observers.

The Glacier Media investigation found a quarter of BC Hydro's power comes from the Mica, Revelstoke and Hugh Keenleyside dams on the Columbia River. Some 29% comes from dams in the Peace region, including the under-construction Site C project that has faced cost overruns. At certain points of the year, those reservoirs are reliant on glacier water.

Still, BC Hydro remains optimistic.

Forecasts are currently showing little rain in the near-term; however, historically, precipitation and inflows show up by the end of October. If that does not happen, BC Hydro said it would continue to closely track weather and inflow forecasts to adapt its operations to protect fish, while regional cooperation such as bridging with Alberta remains part of broader policy discussions.

Among things BC Hydro said it is doing to adapt are:

Continuously working to improve its weather and inflow forecasting;
Expanding its hydroclimate monitoring technology, including custom-made solutions that have been designed in-house, as well as upgrading snow survey stations to automated, real-time snow and climate stations, and;
Investing in capital projects — like spillway gate replacements — that will increase resiliency of the system to climate change.

 

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