Plant planned for Wise hits snag

California Renewable Energy Curtailment highlights grid congestion, midday solar peaks, limited battery storage, and market constraints, with WEIM participation and demand response programs proposed to balance supply-demand and reduce wasted solar and wind generation.

Key Points

It is the deliberate reduction of solar and wind output when grid limits or low demand prevent full integration.

✅ Grid congestion restricts transmission capacity

✅ Midday solar peaks exceed demand, causing surplus

✅ Storage, WEIM, and demand response mitigate curtailment

California has long been a leader in renewable energy adoption, achieving a near-100% renewable milestone in recent years, particularly in solar and wind power. However, as the state continues to expand its renewable energy capacity, it faces a growing challenge: the curtailment of excess solar and wind energy. Curtailment refers to the deliberate reduction of power output from renewable sources when the supply exceeds demand or when the grid cannot accommodate the additional electricity.

Increasing Curtailment Trends

Recent data from the U.S. Energy Information Administration (EIA) highlights a concerning upward trend in curtailments in California. In 2024, the state curtailed a total of 3,102 gigawatt-hours (GWh) of electricity generated from solar and wind sources, surpassing the 2023 total of 2,660 GWh. This represents a 32.4% increase from the previous year. Specifically, 2,892 GWh were from solar, and 210 GWh were from wind, marking increases of 31.2% and 51.1%, respectively, compared to the first nine months of 2023.

Causes of Increased Curtailment

Several factors contribute to the rising levels of curtailment:

1. Grid Congestion: California's transmission infrastructure has struggled to keep pace with the rapid growth of renewable energy sources. This congestion limits the ability to transport electricity from generation sites to demand centers, leading to curtailment.
   
   

2. Midday Solar Peaks: Amid California's solar boom, solar energy production typically peaks during the midday when electricity demand is lower. This mismatch between supply and demand results in excess energy that cannot be utilized, necessitating curtailment.
   
   

3. Limited Energy Storage: While battery storage technologies are advancing, California's current storage capacity is insufficient to absorb and store excess renewable energy for later use. This limitation exacerbates curtailment issues.
   
   

4. Regulatory and Market Constraints: Existing market structures and regulatory frameworks may not fully accommodate the rapid influx of renewable energy, leading to inefficiencies and increased curtailment.

Economic and Environmental Implications

Curtailment has significant economic and environmental consequences. For renewable energy producers, curtailed energy represents lost revenue and undermines the economic viability of new projects. Environmentally, curtailment means that clean, renewable energy is wasted, and the grid may rely more heavily on fossil fuels to meet demand, counteracting the benefits of renewable energy adoption.

Mitigation Strategies

To address the rising curtailment levels, California is exploring several strategies aligned with broader decarbonization goals across the U.S.:

• Grid Modernization: Investing in and upgrading transmission infrastructure to alleviate congestion and improve the integration of renewable energy sources.
  
  

• Energy Storage Expansion: Increasing the deployment of battery storage systems to store excess energy during peak production times and release it during periods of high demand.
  
  

• Market Reforms: Participating in the Western Energy Imbalance Market (WEIM), a real-time energy market that allows for the balancing of supply and demand across a broader region, helping to reduce curtailment.
  
  

• Demand Response Programs: Implementing programs that encourage consumers to adjust their energy usage patterns, such as shifting electricity use to times when renewable energy is abundant.

Looking Ahead

As California continues to expand its renewable energy capacity, addressing curtailment will be crucial to ensuring the effectiveness and sustainability of its energy transition. By investing in grid infrastructure, energy storage, and market reforms, the state can reduce curtailment levels and make better use of its renewable energy resources, while managing challenges like wildfire smoke impacts on solar output. These efforts will not only enhance the economic viability of renewable energy projects but also contribute to California's 100% clean energy targets by maximizing the use of clean energy and reducing reliance on fossil fuels.

While California's renewable energy sector faces challenges related to curtailment, proactive measures and strategic investments can mitigate these issues, as scientists continue to improve solar and wind power through innovation, paving the way for a more sustainable and efficient energy future.

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Heathrow Airport Power Outage 2025 disrupted operations with mass flight cancellations and diversions after a grid failure, exposing infrastructure resilience gaps, crisis management flaws, and raising passenger compensation and safety oversight concerns.

Key Points

A grid failure closed Heathrow, causing mass cancellations and diversions, exposing resilience and communication lapses.

✅ Grid fire triggered airport-wide shutdown

✅ 1,400+ flights canceled or diverted

✅ Inquiry probes resilience, communication, compensation

On March 21, 2025, Heathrow Airport, Europe's busiest, suffered a catastrophic power outage, similar to another high-profile outage seen at major events, that led to the cancellation and diversion of over 1,400 flights, affecting nearly 300,000 passengers and costing airlines an estimated £100 million. The power failure, triggered by a fire at an electricity substation in west London, left Heathrow with a significant operational crisis. This disruption is even more significant considering that Heathrow is one of the most expensive airports globally, which raises concerns about its infrastructure resilience and broader electricity system resilience across Europe.

In a parliamentary committee meeting, Heathrow officials admitted that vulnerabilities in the airport’s power supply were flagged just days before the outage. Nigel Wicking, Chief Executive of the Heathrow Airline Operators' Committee (HAOC), informed MPs that concerns regarding power resilience had been raised on March 15, following disruptions caused by cable thefts impacting runway lights. Despite these warnings, the airport’s management did not address the vulnerabilities urgently, even as UK net zero policies continue to reshape infrastructure planning, which ultimately led to the disastrous outage.

The airport was closed for a day, with serious consequences for not only airlines but also the surrounding community and businesses. British Airways alone faced millions of pounds in losses, and passengers experienced significant emotional distress, missing vital life events like weddings and funerals due to flight cancellations. The committee is now questioning officials from National Grid and Scottish and Southern Electricity Networks to better understand why Heathrow’s infrastructure failed, in the context of a cleaner grid following the British carbon tax that reduced coal use, how it communicated with affected parties, and what measures will be taken to compensate impacted passengers.

Heathrow’s Chief Executive, Thomas Woldbye, defended the closure decision, stating it would have been disastrous to keep the airport open under such circumstances. He noted that continuing operations would have left tens of thousands of passengers stranded and would have posed safety risks due to the failure of fire surveillance and CCTV systems. However, Wicking, representing the airlines, pointed out that Heathrow’s lack of resilience was unacceptable given the amount spent on the airport, emphasizing the need for better infrastructure, including addressing SF6 in switchgear during upgrades, and more transparent management practices.

Looking forward, the MPs intend to investigate the airport’s emergency preparedness, why the resilience review from 2018 wasn’t shared with airlines, and whether enough preventative measures were in place amid surging data demand that could strain electricity supplies. The outcome of this inquiry could have lasting effects on how Heathrow and other major airports handle their infrastructure and crisis management systems, as drought-driven hydro challenges demonstrate the wider climate stresses on power networks.

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Entergy COVID-19 Emergency Relief Fund provides financial assistance to ALICE households, low-income seniors, and disabled customers via United Way grants for rent, mortgage, utilities, food, and bill payment support during COVID-19, alongside a disconnect moratorium.

Key Points

A shareholder-funded program offering essential grants and bill support to Entergy customers affected by COVID-19.

✅ Shareholders commit $700,000; grants distributed via United Way partners.

✅ Focus on ALICE families, low-income seniors, and disabled customers.

✅ Disconnects suspended; bill tools and LIHEAP advocacy underway.

In an effort to help working families experiencing financial hardships as a result of the coronavirus pandemic, the Entergy Charitable Foundation has established the COVID-19 Emergency Relief Fund, recognizing the need for electricity across communities.

"The health and safety of our customers, employees and communities is Entergy's top priority," said Leo Denault, chairman and CEO of Entergy Corporation. "For more than 100 years, Entergy has never wavered in our commitment to supporting our customers and the communities we serve. This pandemic is no different. During this challenging time, we are helping lessen the impact of this crisis on the most vulnerable in our communities. I strongly encourage our business partners to join us in this effort."

As devastating and disruptive as this crisis is for everyone, we know from past experience that those most heavily impacted are ALICE households (low-wage working families) and low-income elderly and disabled customers, who often face energy insecurity during such events - roughly 40%-50% of Entergy's customer base.

"We know from experience that working families and low-income elderly and disabled customers are hardest hit during times of crisis," said Patty Riddlebarger, vice president of Entergy's corporate social responsibility. "We are working quickly to make funds available to community partners that serve vulnerable households to lessen the economic impact of the COVID-19 crisis and ensure that families have the resources they need to get by during this time of uncertainty."

To support our most vulnerable customers, Entergy shareholders are committing $700,000 to the COVID-19 Emergency Relief Fund to help qualifying customers with basic needs such as food and nutrition, rent and mortgage assistance, and other critical needs, alongside measures like Texas utilities waiving fees that ease household costs, until financial situations become more stable. Grants from the fund will be provided to United Way organizations and other nonprofit partners across Entergy's service area that are providing services to impacted households.

Company shareholders will also match employee contributions to the COVID-19 relief efforts of local United Way organizations up to $100,000 to maximize impact.

In addition to establishing the COVID-19 Emergency Relief Fund, Entergy is taking additional steps to support and protect our customers during this crisis, similar to PG&E's pandemic response measures, including:

With support from our regulators, we are temporarily suspending customer disconnects, as seen in New Jersey and New York policies, as we continue to monitor the situation.

We are working with our network of community advocates, as the industry coordination with federal partners continues, to request a funding increase of the Low Income Home Energy Assistance Program to help alleviate financial hardships caused by COVID-19 on vulnerable households.

We are developing bill payment solutions and tools to help customers pay their accumulated balances once the disconnect moratorium is lifted.

Already in place to support vulnerable customers is Entergy's The Power to Care program, which provides emergency bill payment assistance to seniors and disabled individuals. To mark the 20th anniversary of Entergy's low-income customer initiative, the limit of shareholders' dollar for dollar match of customer donations was increased from $500,000 to $1 million per year. Shareholders continue to match employee donations dollar for dollar with no limit.

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Utility Battery Storage Rankings measure grid-connected capacity, not ownership, highlighting MW, MWh, and watts per customer across PJM, MISO, and California IOUs, featuring Duke Energy, IPL, ancillary services, and frequency regulation benefits.

Key Points

Rankings that track energy storage connected to utility grids, comparing MW, MWh, and W/customer rather than ownership.

✅ Ranks by MW, MWh, and watts per customer, not asset ownership

✅ Highlights PJM, MISO cases and California IOUs' deployments

✅ Examples: Duke Energy, IPL, IID; ancillary services, frequency response

The rankings do not tally how much energy storage a utility built or owns, but how much was connected to their system. So while IPL built and owns the storage facility in its territory, Duke does not own the 16 MW of storage that connected to its system in 2016. Similarly, while California’s utilities are permitted to own some energy storage assets, they do not necessarily own all the storage facilities connected to their systems.

Measured by energy (MWh), IPL ranked fourth with 20 MWh, and Duke Energy Ohio ranked eighth with 6.1 MWh.

Ranked by energy storage watts per customer, IPL and Duke actually beat the California utilities, ranking fifth and sixth with 42 W/customer and 23 W/customer, respectively.

Duke ready for next step

Given Duke’s plans, including projects in Florida that are moving ahead, the utility is likely to stay high in the rankings and be more of a driving force in development. “Battery technology has matured, and we are ready to take the next step,” Duke spokesman Randy Wheeless told Utility Dive. “We can go to regulators and say this makes economic sense.”

Duke began exploring energy storage in 2012, and until now most of its energy storage efforts were focused on commercial projects in competitive markets where it was possible to earn revenues. Those included its 36 MW Notrees battery storage project developed in partnership with the Department of Energy in 2012 that provides frequency regulation for the Electric Reliability Council of Texas market and two 2 MW storage projects at its retired W.C. Beckjord plant in New Richmond, Ohio, that sells ancillary services into the PJM Interconnection market.

On the regulated side, most of Duke’s storage projects have had “an R&D slant to them,” Wheeless said, but “we are moving beyond the R&D concept in our regulated territory and are looking at storage more as a regulated asset.”

“We have done the demos, and they have proved out,” Wheeless said. Storage may not be ready for prime time everywhere, he said, but in certain locations, especially where it can it can be used to do more than one thing, it can make sense.

Wheeless said Duke would be making “a number of energy storage announcements in the next few months in our regulated states.” He could not provide details on those projects.

More flexible resources
Location can be a determining factor when building a storage facility. For IPL, serving the wholesale market was a driving factor in the rationale to build its 20 MW, 20 MWh storage facility in Indianapolis.

IPL built the project to address a need for more flexible resources in light of “recent changes in our resource mix,” including decreasing coal-fired generation and increasing renewables and natural gas-fired generation, as other regions plan to rely on battery storage to meet rising demand, Joan Soller, IPL’s director of resource planning, told Utility Dive in an email. The storage facility is used to provide primary frequency response necessary for grid stability.

The Harding Street storage facility in May. It was the first energy storage project in the Midcontinent ISO. But the regulatory path in MISO is not as clear as it is in PJM, whereas initiatives such as Ontario storage framework are clarifying participation. In November, IPL with the Federal Energy Regulatory Commission, asking the regulator to find that MISO’s rules for energy storage are deficient and should be revised.

Soller said IPL has “no imminent plans to install energy storage in the future but will continue to monitor battery costs and capabilities as potential resources in future Integrated Resource Plans.”

California legislative and regulatory push

In California, energy storage did not have to wait for regulations to catch up with technology. With legislative and regulatory mandates, including CEC long-duration storage funding announced recently, as a push, California’s IOUs took high places in SEPA’s rankings.

Southern California Edison and San Diego Gas & Electric were first and fourth (63.2 MW and 17.2 MW), respectively, in terms of capacity. SoCal Ed and SDG&E were first and second (104 MWh and 28.4 MWh), respectively, and Pacific Gas and Electric was fifth (17 MWh) in terms of energy.

But a public power utility, the Imperial Irrigation District (IID), ended up high in the rankings – second in capacity (30 MW) and third  in energy (20 MWh) – even though as a public power entity it is not subject to the state’s energy storage mandates.

But while IID was not under state mandate, it had a compelling regulatory reason to build the storage project. It was part of a settlement reached with FERC over a September 2011 outage, IID spokeswoman Marion Champion said.

IID agreed to a $12 million fine as part of the settlement, of which $9 million was applied to physical improvements of IID’s system.

IID ended up building a 30 MW, 20 MWh lithium-ion battery storage system at its El Centro generating station. The system went into service in October 2016 and in May, IID used the system’s 44 MW combined-cycle natural gas turbine at the generating station.

Passing savings to customers
The cost of the storage system was about $31 million, and based on its experience with the El Centro project, Champion said IID plans to add to the existing batteries. “We are continuing to see real savings and are passing those savings on to our customers,” she said.

Champion said the battery system gives IID the ability to provide ancillary services without having to run its larger generation units, such as El Centro Unit 4, at its minimum output. With gas prices at $3.59 per million British thermal units, it costs about $26,880 a day to run Unit 4, she said.

IID’s territory is in southeastern California, an area with a lot of renewable resources. IID is also not part of the California ISO and acts as its own balancing authority. The battery system gives the utility greater operational flexibility, in addition to the ability to use more of the surrounding renewable resources, Champion said.

In May, IID’s board gave the utility’s staff approval to enter into contract negotiations for a 7 MW, 4 MWh expansion of its El Centro storage facility. The negotiations are ongoing, but approval could come in the next couple months, Champion said.

The heart of the issue, though, is “the ability of the battery system to lower costs for our ratepayers,” Champion said. “Our planning section will continue to utilize the battery, and we are looking forward to its expansion,” she said.” I expect it will play an even more important role as we continue to increase our percentage of renewables.”

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Ontario Darlington SMR Expansion advances four GE Hitachi BWRX-300 reactors with OPG, adding 1,200 MW of baseload nuclear power to support electrification, grid reliability, and clean energy growth across Ontario and Saskatchewan.

Key Points

Plan to build four BWRX-300 SMRs at Darlington, delivering 1,200 MW of clean, reliable baseload power under OPG.

✅ Four GE Hitachi BWRX-300 units, 1,200 MW total

✅ Shared infrastructure cuts costs and timelines

✅ Supports electrification, grid reliability, net zero

The day after Ontario announced it would be building an additional 4,800 megawatts of nuclear reactors at Bruce Nuclear Generating Station, the province announced it would be dramatically expanding its planned rollout of small modular reactors at its Darlington Nuclear Generating Station, and confirmed plans to refurbish Pickering B as part of its broader strategy.

Ontario Power Generation OPG was always going to be the first to build the GE-Hitachi BWRX-300 small modular reactor SMR, with the U.S.’s Tennessee Valley Authority among others like SaskPower and several European nations following suit. But the OPG was originally going to build just one. On July 7, OPG and the Province of Ontario announced they would be bumping that up to four units of the BWRX-300.

The Ontario government is working with Ontario Power Generation (OPG) to commence planning and licensing for three additional small modular reactors (SMRs), for a total of four SMRs at the Darlington nuclear site. Once deployed, these four units would produce a total 1,200 megawatts (MW) of electricity, equivalent to powering 1.2 million homes, helping to meet increasing demand from electrification and fuel the province’s strong economic growth, the Ontario Ministry of Energy said in a release.

“Our government’s open for business approach has led to unprecedented investments across the province — from electric vehicles and battery manufacturing to critical minerals to green steel,” said Todd Smith, Minister of Energy. “Expanding Ontario’s world-leading SMR program will ensure we have the reliable, affordable and clean electricity we need to power the next major international investment, the new homes we are building and industries as they grow and electrify.”

For the first time since 2005, Ontario’s electricity demand is rising. While the government has implemented its plan to meet rising electricity demand this decade, the experts at Ontario’s Independent Electricity System Operator have recommended the province advance new nuclear generation and pursue life-extension at Pickering NGS to provide reliable, baseload power to meet increasing electricity needs in the 2030s and beyond.

Subject to Ontario Government and Canadian Nuclear Safety Commission (CNSC) regulatory approvals on construction, the additional SMRs could come online between 2034 and 2036. That is the same timeframe that SaskPower is looking at for its first, and possibly second, units.

The initial unit is expected to go online in 2028 following Ontario’s first SMR groundbreaking at Darlington.

The Darlington site, which already hosts four reactors, was originally considered for an expansion of “large nuclear,” which is why OPG was already well on its way for site approvals of additional nuclear power generation. The plan changed to one, singular, SMR. Now that has been updated to four.

The announcement has significant impact on Saskatchewan, and its plans to build four of its own SMRs. The timing would allow Ontario Power Generation to apply learnings from the construction of the first unit to deliver cost savings on subsequent units. This is also the strategy SaskPower is following – allow Ontario to build the first, then learn from that experience.

Building multiple units will also allow common infrastructure such as cooling water intake, transmission connection and control room to be utilized by all four units instead of just one, reducing costs even further, the Ministry said.

“A fleet of SMRs at the Darlington New Nuclear Site is key to meeting growing electricity demands and net zero goals,” said Ken Hartwick, OPG President and CEO. “OPG has proven its large nuclear project expertise through the on-time, on budget Darlington Refurbishment project. By taking a similar approach to building a fleet of SMRs, we will deliver cost and schedule savings, and power 1.2 million homes from this site by the mid-2030s.”

The Darlington SMR project is situated on the traditional and treaty territories of the seven Williams Treaties First Nations and is also located within the traditional territory of the Huron Wendat peoples. OPG is actively engaging and consulting with potentially impacted Indigenous communities, including exploring economic opportunities in the Darlington SMR project such as commercial participation and employment.

The Ministry noted, “Ontario’s robust nuclear supply chain is uniquely positioned to support SMR development and deployment in Ontario, Canada and globally. Building additional SMRs at Darlington would provide more opportunities for Ontario companies and broader economic benefits as suppliers of nuclear equipment, components, and services to make further investments to expand their operation to serve the growing SMR market both domestically and abroad.”

Supporting new SMR development and investing in nuclear power is part of the Ontario government’s larger plan, aligned with a Canadian interprovincial nuclear initiative that brings provinces together, to prepare for electricity demand in the 2030s and 2040s that will build on Ontario’s clean electricity advantage and ensure the province has the power to maintain it’s position as leader in job creation and a magnet for the industries of the future, the Ministry said.

In February, World Nuclear News (WNN) reported that Poland was considering up to 79 small modular reactors of the same design as OPG and SaskPower. And on June 5, it reported, “Canada’s Ontario Power Generation will provide operator services to Poland’s Orlen Synthos Green Energy under a letter of intent signed between the partners, extending their existing cooperation on the deployment of small modular reactors.”

WNN added, “The letter of intent is aimed at concluding future agreements under which OPG and its subsidiaries could provide operator services for SMR reactors to OSGE in connection with the deployment of SMRs in Poland and other European countries. The partnership would include a number of SMR-related activities including: development and deployment; operations and maintenance; operator training; commissioning; and regulatory support.”

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EU Renewable Energy Transition is accelerating under REPowerEU, as wind and solar generation hit records, improving energy security, efficiency, and decarbonization while reducing reliance on Russian fossil fuels across the EU grid.

Key Points

EU shift to wind and solar under REPowerEU to cut fossil fuels, boost efficiency, and secure energy supply.

✅ Wind and solar set record 22% of EU electricity in 2022

✅ REPowerEU targets over 40% renewables and 15% lower demand by 2030

✅ Diversifies away from Russian fuels; partners with US and Norway

Europe is producing all-time highs of wind and solar energy as the 27-country group works to reduce its reliance on fossil fuels from Russia, a shift underscored by Europe's green surge across the bloc.

Four months after Vladimir Putin’s full-scale invasion of Ukraine in February 2022, the European Commission launched REPowerEU. This campaign aims to:

• Boost the use of renewable energy.
• Reduce overall energy consumption.
• Diversify energy sources.

EU countries were already moving toward renewable energy, but Russia’s war against Ukraine accelerated that trend. In 2022, for the first time, renewables surpassed fossil fuels and wind and solar power surpassed gas as a source of electricity. Wind and solar provided a record-breaking 22% of EU countries’ electrical supply, according to London-based energy think tank Ember.

“We have to double down on investments in home-grown renewables,” European Commission President Ursula von der Leyen said in October 2022. “Not only for the climate but also because the transition to the clean energy is the best way to gain independence and to have security of energy supply.”

Across the continent, growth in solar generation rose by 25% in 2022, according to Ember, as solar reshapes electricity prices in Northern Europe. Twenty EU countries produced their highest share of solar power in 2022. In October, Greece ran entirely on renewables for several hours and is seven years ahead of schedule for its 2030 solar capacity target.

Meanwhile, Ireland's green electricity target aims to make more than a third of its power supply renewable within four years.

By 2030, RePowerEU aims to provide more than 40% of the EU’s total power from renewables, aligning with global renewable records being shattered worldwide.

To meet the European Commission’s goal to cut EU energy usage by 15%, people and governments changed their habits and became more energy-efficient, while Germany's solar power boost helped bolster supply. Among their actions:

• Germany turned down the heat in public buildings and lowered the cost of train tickets to reduce car usage, as clean energy hit 50% in Germany during this period.
• Spain ordered stores and public buildings to turn off their lights at night.
• France dimmed the Eiffel Tower and reduced city speed limits.

For the oil and gas that the EU still needed to import, countries turned to partners such as Norway and the United States.

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