Hydro One transmission service in Toronto stabilized

By Hydro One


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Hydro One reports that its Toronto area transmission system has been stabilized and has resumed normal operations.

Flash flooding resulting from the Monday, July 8, 2013 storm in Toronto flooded two critical west end Toronto transmission stations causing power disruptions to Toronto Hydro and Enersource Hydro Mississauga customers.

The Company reconfigured the local transmission system to bring power back to customers as quickly as possible however, the system continued to operate in emergency mode until efforts to restore the grid to its normal operation were completed.

"I am pleased to confirm that our system has now been stabilized, said Carmine Marcello, President and CEO, Hydro One. "We regret the disruption this unprecedented event caused many people in the City of Toronto but appreciated their patience as we worked to bring our system back to normal operation. We are also grateful for the tremendous support we received from the Province, the City of Toronto, and Toronto Hydro while we worked around the clock to normalize our operation."

Hydro One has an established policy to conduct formal reviews of major system events. This review will involve, but is not limited to, a review and assessment of:

- restoration efforts and the communication

- effectiveness of emergency operational procedures and plans, operations infrastructure

- power system design and redundancy

- engineering design standards

- assumptions with respect to environmental issues such as storm and water intensities and how they relate to the design and hardening of electricity facilities.

Hydro One delivers electricity safely, reliably and responsibly to homes and businesses across the province of Ontario and owns and operates Ontario's 29,000 km high-voltage transmission network that delivers electricity to large industrial customers and municipal utilities, and a 123,000 km low-voltage distribution system that serves about 1.3 million end-use customers and smaller municipal utilities in the province. Hydro One is wholly owned by the Province of Ontario.

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New England's solar growth is creating tension over who pays for grid upgrades

New England Solar Interconnection Costs highlight distributed generation strains, transmission charges, distribution upgrades, and DAF fees as National Grid maps hosting capacity, driving queue delays and FERC disputes in Rhode Island and Massachusetts.

 

Key Points

Rising upfront grid upgrade and DAF charges for distributed solar in RI and MA, including some transmission costs.

✅ Upfront grid upgrades shifted to project developers

✅ DAF and transmission charges increase per MW costs

✅ Queue delays tied to hosting capacity and cluster studies

 

Solar developers in Rhode Island and Massachusetts say soaring charges to interconnect with the electric grid are threatening the viability of projects. 

As more large-scale solar projects line up for connections, developers are being charged upfront for the full cost of the infrastructure upgrades required, a long-common practice that they say is now becoming untenable amid debates over a new solar customer charge in Nova Scotia. 

“It is a huge issue that reflects an under-invested grid that is not ready for the volume of distributed generation that we’re seeing and that we need, particularly solar,” said Jeremy McDiarmid, vice president for policy and government affairs at the Northeast Clean Energy Council, a nonprofit business organization. 

Connecting solar and wind systems to the grid often requires upgrades to the distribution system to prevent problems, such as voltage fluctuations and reliability risks highlighted by Australian distributors in their networks. Costs can vary considerably from place to place, depending on the amount of distributed generation coming online and the level of capacity planning by regulators, said David Feldman, a senior financial analyst at the National Renewable Energy Laboratory.

“Certainly the Northeast often has more distribution challenges than much of the rest of the country just because it’s more populous and often the infrastructure is older,” he said. “But it’s not unique to the Northeast — in the Midwest, for example, there’s a significant amount of wind projects in the queues and significant delays.”

In Rhode Island and Massachusetts, where strong incentive programs are driving solar development, the level of solar coming online is “exposing the under-investment in the distribution system that is causing these massive costs that National Grid is assigning to particular projects or particular groups of projects,” McDiarmid said. “It is going to be a limiting factor for how much clean energy we can develop and bring online.”

Frank Epps, chief executive officer at Energy Development Partners, has been developing solar projects in Rhode Island since 2010. In that time, he said, interconnection charges on his projects have grown from about $80,000-$120,000 per megawatt to more than $400,000 per megawatt. He attributed the increase to a lack of investment in the distribution network by National Grid over the last decade.

He and other developers say the utility is now adding further to their costs by passing along not just the cost of improving the distribution system — the equivalent of the city street of the grid that brings power directly to customers — but also costs for modifying the transmission system — the interstate highway that moves bulk power over long distances to substations. 

Solar developers who are only requesting to hook into the distribution system, and not applying for transmission service, say they should not be charged for those additional upgrades under state interconnection rules unless they are properly authorized under the federal law that governs the transmission system. 

A Rhode Island solar and wind developer filed a complaint with the Federal Energy Regulatory Commission in February over transmission system improvement charges for its four proposed solar projects. Green Development said National Grid subsidiaries Narragansett Electric and New England Power Company want to charge the company more than $500,000 a year in operating and maintenance expenses assessed as so-called direct assignment facility charges. 

“This amount nearly doubles the interconnection costs associated with the projects,” which total 38.4 megawatts in North Smithfield, the company says in its complaint. “Crucially, these charges are linked to recovering costs associated with providing transmission service — even though no such transmission service is being provided to Green Development.”

But Ted Kresse, a spokesperson for National Grid, said the direct assignment facility, or DAF, construct has been in place for decades and has been applied to any customer affecting the need for transmission upgrades.

“It is the result of the high penetration and continued high volume of distributed generation interconnections that has recently prompted the need for transmission upgrades, and subsequently the pass-through of the associated DAF charges,” he said. 

Several complaints before the Rhode Island Public Utilities Commission object to these DAF and other transmission charges.

One petition for dispute resolution concerns four solar projects totaling 40 MW being developed by Energy Development Partners in a former gravel pit in North Kingstown. Brown University has agreed to purchase the power. 

The developer signed interconnection service agreements with Narragansett Electric in 2019 requiring payment of $21.6 million for costs associated with connecting the projects at a new Wickford Junction substation. Last summer, Narragansett sought to replace those agreements with new ones that reclassified a portion of the costs as transmission-level costs, through New England Power, National Grid’s transmission subsidiary.

That shift would result in additional operational and maintenance charges of $835,000 per year for the estimated 35-year life of the projects, the complaint says.

“This came as a complete shock to us,” Epps said. “We’re not just paying for the maintenance of a new substation. We are paying a share of the total cost that the system owner has to own and operate the transmission system. So all of the sudden, it makes it even tougher for distributed energy resources to be viable.”

In its response to the petition, National Grid argues that the charges are justified because the solar projects will require transmission-level upgrades at the new substation. The company argues that the developer should be responsible for the costs rather than ratepayers, “who are already supporting renewable energy development through their electric rates.”

Seth Handy, one of the lawyers representing Green Development in the FERC complaint, argues that putting transmission system costs on distribution assets is unfair because the distributed resources are “actually reducing the need to move electricity long distances. We’ve been fighting these fights a long time over the underestimating of the value of distributed energy in reducing system costs.”

Handy is also representing the Episcopal Diocese of Rhode Island before the state Supreme Court in its appeal of an April 2020 public utilities commission order upholding similar charges for a proposed 2.2-megawatt solar project at the diocese’s conference center and camp in Glocester. 

Todd Bianco, principal policy associate at the utilities commission, said neither he nor the chairperson can comment on the pending dockets contesting these charges. But he noted that some of these issues are under discussion in another docket examining National Grid’s standards for connecting distributed generation. Among the proposals being considered is the appointment of an independent ombudsperson to resolve interconnection disputes. 

Separately, legislation pending before the Rhode Island General Assembly would remove responsibility for administering the interconnection of renewable energy from utilities, and put it under the authority of the Rhode Island Infrastructure Bank, a financing agency.

Handy, who recently testified in support of the bill, said he believes National Grid has too many conflicting interests to administer interconnecting charges in a timely, transparent and fair fashion, and pointed to utility moves such as changes to solar compensation in other states as examples. In particular, he noted the company’s interests in expanding natural gas infrastructure. 

“There are all kinds of economic interests that they have that conflict with our state policy to provide lower-cost renewable energy and more secure energy solutions,” Handy said.

In testimony submitted to the House Committee on Corporations opposing the legislation, National Grid said such powers are well beyond the purpose and scope of the infrastructure bank. And it cited figures showing Rhode Island is third in the country for the most installed solar per square mile (behind New Jersey and Massachusetts).

Nadav Enbar, program manager at the Electric Power Research Institute, a nonprofit research organization for the utility industry, said interconnection delays and higher costs are becoming more common due to “the incredible uptake” in distributed renewable energy, particularly solar.

That’s impacting hosting capacity, the room available to connect all resources to a circuit without causing adverse harm to reliability and safety. 

“As hosting capacity is being reduced, it’s causing an increasing number of situations where utilities need to study their systems to guarantee interconnection without compromising their systems,” he said. “And that is the reason why you’re starting to see some delays, and it has translated into some greater costs because of the need for upgrades to infrastructure.”

The cost depends on the age or absence of infrastructure, projected load growth, the number of renewable energy projects in the queue, and other factors, he said. As utilities come under increasing pressure to meet state renewable goals, and as some states pilot incentives like a distributed energy rebate in Illinois to drive utility innovation, some (including National Grid) are beginning to provide hosting capacity maps that provide detailed information to developers and policymakers about the amount of distributed energy that can be accommodated at various locations on the grid, he said. 

In addition, the coming availability of high-tech “smart inverters” should help ease some of these problems because they provide the grid with more flexibility when it comes to connecting and communicating with distributed energy resources, Enbar said. 

In Massachusetts, the Department of Public Utilities has opened a docket to explore ways to better plan for and share the cost of upgrading distribution infrastructure to accommodate solar and other renewable energy sources as part of a grid overhaul for renewables nationwide. National Grid has been conducting “cluster studies” there that attempt to analyze the transmission impacts of a group of solar projects and the corresponding interconnection cost to each developer.

Kresse, of National Grid, said the company favors cost-sharing methodologies under consideration that would “provide a pathway to spread cost over the total enabled capacity from the upgrade, as opposed to spreading the cost over only those customers in the queue today.” 

Solar developers want regulators to take an even broader approach that factors in how the deployment of renewables and the resulting infrastructure upgrades benefit not just the interconnecting generator, but all customers. 

“Right now, if your project is the one that causes a multimillion-dollar upgrade, you are assigned that cost even though that upgrade is going to benefit a lot of other projects, as well as make the grid stronger,” said McDiarmid, of the clean energy council. “What we’re asking for is a way of allocating those costs among a variety of developers, as well as to the grid itself, meaning ratepayers. There’s a societal benefit to increasing the modernization of the grid, and improving the resilience of the grid.”

In the meantime, BlueHub Capital, a Boston-based solar developer focused on serving affordable housing developments, recently learned from National Grid that, as a part of one of the area studies, it will be required to pay $5.8 million in transmission and distribution upgrades to interconnect a 2-megawatt solar-plus-storage project that leverages cheaper batteries to enhance resilience, approved for a brownfield site in Gardner, Massachusetts. 

According to testimony submitted to the department, the sum is supposed to be paid within the next year, even though the project will have to wait to be interconnected until April 2027, when a new transmission line is completed. In addition, BlueHub will be responsible for DAF charges totaling $3.4 million over the 20-year life of the project. 

“We’re being asked to pay a fortune to provide solar that the state wants,” said DeWitt Jones, BlueHub’s president. “It’s so expensive that the upgrades are driving everyone out of the interconnection queue. The costs stay the same, but they fall on fewer projects. We need a process of grid design and modernization to guide this.”

 

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Customers on the hook for $5.5 billion in deferred BC Hydro operating costs: report

BC Hydro Deferred Regulatory Assets detail $5.5 billion in costs under rate-regulated accounting, to be recovered from ratepayers, highlighting B.C. Utilities Commission oversight, audit scrutiny, financial reporting impacts, and public utility governance.

 

Key Points

BC Hydro defers costs as regulatory assets to recover from ratepayers, influencing rates and financial reporting.

✅ $5.5B in deferred costs recorded as net regulatory assets

✅ Rate impacts tied to B.C. Utilities Commission oversight

✅ Auditor General to assess accounting and governance

 

Auditor General Carol Bellringer says BC Hydro has deferred $5.5 billion in expenses that it plans to recover from ratepayers in the future, as rates to rise by 3.75% over two years.

Bellringer focuses on the deferred expenses in a report on the public utility's use of rate-regulated accounting to control electricity rates for customers.

"As of March 31, 2018, BC Hydro reported a total net regulatory asset of $5.455 billion, which is what ratepayers owe," says the report. "BC Hydro expects to recover this from ratepayers in the future. For BC Hydro, this is an asset. For ratepayers, this is a debt."

She says rate-regulated accounting is used widely across North America, but cautions that Hydro has largely overridden the role of the independent B.C. Utilities Commission to regulate rates.

"We think it's important for the people of B.C. and our members of the legislative assembly to better understand rate-regulated accounting in order to appreciate the impact it has on the bottom line for BC Hydro, for government as a whole, for ratepayers and for taxpayers, especially following a three per cent rate increase in April 2018," Bellringer said in a conference call with reporters.

Last June, the B.C. government launched a two-phase review of BC Hydro to find cost savings and look at the direction of the Crown utility, amid calls for change from advocates.

The review came shortly after a planned government rate freeze was overturned by the utilities commission, which resulted in a three per cent rate increase in April 2018.

A statement by BC Hydro and the government says a key objective of the review due this month is to enhance the regulatory oversight of the commission.

Bellringer's office will become BC Hydro's auditor next year — and will be assessing the impact of regulation on the utility's financial reporting.

"It is a complex area and confidence in the regulatory system is critical to protect the public interest," wrote Bellringer.

 

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Ontario Providing Support for Industrial and Commercial Electricity Consumers During COVID-19

Ontario Global Adjustment Deferral provides COVID-19 relief to industrial and commercial electricity consumers, holding GA charges at pre-COVID levels, aligning Class A and Class B rates, and deferring non-RPP costs from April to June 2020.

 

Key Points

An emergency measure that defers a portion of GA charges to stabilize electricity bills for non-RPP Class A/B consumers.

✅ Holds GA near pre-COVID levels at $115/MWh for Class B.

✅ Applies equal percentage relief to Class A customers.

✅ Deferred costs recovered over 12 months from Jan 2021.

 

Through an emergency order passed today, the Ontario government is taking steps to defer a portion of Global Adjustment (GA) charges for industrial and commercial electricity consumers that do not participate in the Regulated Price Plan for the period starting from April 2020, at a time when Toronto's growing electricity needs require careful planning. This initiative is intended to provide companies with temporary immediate relief on their monthly electricity bills, as utilities use AI to adapt to shifting electricity demands in April, May and June 2020. The government intends to keep this emergency order in place until May 31, 2020, and subsequent regulatory amendments would, if approved, provide for the deferral of these charges for June 2020 as well.

This relief will prevent a marked increase in Global Adjustment charges due to the low electricity demand caused by the COVID-19 outbreak. Without this emergency order, a small industrial or commercial consumer (i.e., Class B) could have seen bills increase by 15 per cent or more. This emergency order will hold GA rates in line with pre-COVID-19 levels, even as clean energy initiatives in British Columbia accelerate across the sector.

"Ontario's industrial and commercial electricity consumers are being impacted by COVID-19. They employ thousands of hardworking Ontarians, and we know this is a challenging time for them," said Greg Rickford, Minister of Energy, Northern Development and Mines. "This would provide immediate financial support for more than 50,000 companies when they need it most: as they do their part to stop the spread of COVID-19 and as they prepare to help get our economy moving again with Toronto preparing for a surge in electricity demand in the years ahead."

Quick Facts

  • The GA rate for smaller industrial and commercial consumers (i.e., Class B) has been set at $115 per megawatt-hour, which is roughly in line with the March 2020 value, alongside efforts to develop IoT security standards for electricity sector devices today. Large industrial and commercial consumers (i.e., Class A) will receive the same percentage reduction in GA charges as Class B consumers.
  • Subject to the approval of subsequent amendments, deferred costs would be recovered over a 12-month period beginning in January 2021, amid increasing exposure to harsh weather across Canadian grids.

 

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Opinion: The awesome, revolutionary electric-car revolution that doesn't actually exist

Ecofiscal Commission EV Policy Shift examines carbon pricing limits, endorsing signal boosters like subsidies, EV incentives, and coal bans, amid advisory changes and public pushback, to accelerate emissions cuts beyond market-based taxes and regulations.

 

Key Points

An updated stance recognizing carbon pricing limits and backing EV incentives, subsidies, and rules to reduce emissions.

✅ Carbon pricing plus subsidies, EV incentives

✅ Advisory shift; Jack Mintz departs

✅ Focus on emissions cuts, coal power bans

 

Something strange happened at the Ecofiscal Commission recently. Earlier this month, the carbon-tax advocacy group featured on its website as one of its advisers the renowned Canadian economist (and FP Comment columnist) Jack M. Mintz. The other day, suddenly and without fanfare, Mintz was gone from the website, and the commission’s advisory board.

Advisers come and advisers go, of course, but it turns out there was an impetus for Mintz’s departure. The Ecofiscal Commission in its latest report, dropped just before Canada Day, seemingly shifted from its position that carbon prices were so excellent at mimicking market forces that the tax could repeal and replace virtually the entire vast expensive gallimaufry of subsidies, caps, rules and regulations that are costing Canada a fortune in business and bureaucrats. As some Ecofiscal commissioners wrote just a few months ago, policies that “dictate specific technologies or methods for reducing emissions constrain private choice and increase costs” and were a bad idea.

But, in this latest report, the commission is now musing about the benefits of carbon-tax “signal boosters”: that is, EV subsidies and rules to, for instance, get people to start buying electric vehicles (EVs), as well as bans on coal-fired power. “Even well designed carbon pricing can have limitations,” rationalized the commission. Mintz said he had “misgivings” about the change of tack. He decided it best if he focus his advisory energies elsewhere.

It’s hard to blame the commission for falling like everyone else for the electric-car mania that’s sweeping the nation and the world. Electric cars offer a sexiness that dreary old carbon taxes can never hope to match — especially in light of a new Angus Reid poll last week that showed the majority of Canadians now want governments to shelve any plans for carbon taxes.

So far, because nobody’s really driving these miracle machines, said mania has been limited to breathless news reports about how the electric-vehicle revolution is about to rock our world. EVs comprise just two-tenths of a per cent of all passenger vehicles in North America, despite the media’s endless hype and efforts of green-obsessed governments to cover much of the price tag, like Ontario’s $14,000 rebate for Tesla buyers. In Europe, where virtue-signalling urban environmentalism is the coolest, they’re not feeling the vehicular electricity much more: EVs account for barely one per cent of personal vehicles in France, the U.K. and Germany. When Hong Kong cancelled Tesla rebates in April, sales fell to zero.

Going by the ballyhoo, you’d think EVs were at an inflection point and an unstoppable juggernaut. But it’s one that has yet to even get started. In his 2011 State of the Union address, then president Barack Obama predicted one million electric cars on the road by 2015. Four years later, there wasn’t even a third that many. California offered so many different subsidies for electric vehicles that low-income families could get rebates of up to US$13,500, but it still isn’t even close to reaching its target of having zero-emission vehicles make up 15 per cent of California auto sales by 2025, being stuck at three per cent since 2014. Ontario’s Liberal government last year announced to much laughter its plan to ensure that every family would have at least one zero-emission vehicle (ZEV) by 2024, and Quebec made a plan to make ZEVs worth 15.5 per cent of sales by 2020, while Ottawa’s 2035 EV mandate attracts criticism too. Let’s see how that’s going: Currently, ZEVs make up 0.16 per cent of new vehicle sales in Ontario and 0.38 per cent in Quebec.

The latest sensational but bogus EV news out last week was France’s government announcing the “end of the sale of gasoline and diesel cars by 2040,” and Volvo apparently announcing that as of 2019, all its models would be “electric.” Both announcements made international headlines. Both are baloney. France provided no actual details about this plan (will it literally become a crime to sell a gasoline car? Will hybrids, run partly on gasoline, be allowed?), but more importantly, as automotive writer Ed Wiseman pointed out in The Guardian, a lot will happen in technology and automotive use over the next 23 years that France has no way to predict, with changes in self-driving cars, public car-sharing and fuel technologies. Imagine making rules for today’s internet back in 1994.

Volvo, meanwhile, looked to be recycling and repackaging years-old news to seize on today’s infatuation with electric vehicles to burnish its now Chinese-owned brand. Since 2010, Volvo’s plan has been to focus on engines that were partly electric, with electric turbochargers, but still based on gasoline. Volvo doesn’t actually have an all-electric model, but the gasoline-swigging engine of its popular XC90 SUV is, partly, electrical. When Volvo said all its models would in two years be “electric,” it meant this kind of engine, not that it was phasing out the internal-combustion gasoline engine. But that is what it wanted reporters to think, and judging by all the massive and inaccurate coverage, it worked.

The real story being missed is just how pathetic things look right now for electric cars. Gasoline prices in the U.S. turned historically cheap in 2015 and stayed cheap, icing demand for gasless cars. Tesla, whose founder’s self-promotion had made the niche carmaker magically more valuable than powerhouses like Ford and GM, haemorrhaged US$12 billion in market value last week after tepid sales figures brought some investors back to Earth, even as the company’s new Model 3 began rolling off the line.

Not helping is that environmental claims about environmental cars are falling apart. In June, Tesla was rocked by a controversial Swedish study that found that making one of its car batteries released as much CO2 as eight years of gasoline-powered driving. And Bloomberg reported last week on a study by Chinese engineers that found that electric vehicles, because of battery manufacturing and charging by fossil-fuel-powered electricity sources, emit 50-per-cent more carbon than do internal-combustion engines. Still, the electric-vehicle hype not only continues unabated, it gets bigger and louder every day. If some car company figures out how to harness it, we’d finally have a real automotive revolution on our hands.

Kevin Libin, Financial Post

 

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UK windfarms generate record amount of electricity during Storm Malik

UK Wind Power Record as Storm Malik boosts renewable electricity, with National Grid reporting 19,500 megawatts in Scotland, cutting fossil fuel use and easing market prices on the path toward net zero targets.

 

Key Points

An all-time peak in UK wind generation, reaching 19,500 MW during Storm Malik, supplying over half of electricity.

✅ Peak: 19,500 MW, over 50% of UK electricity.

✅ Driven by Storm Malik; strongest winds in Scotland.

✅ Lowered market prices; reduced fossil fuel generation.

 

The UK’s windfarms generated a new record for wind power generation over the weekend as Storm Malik battered parts of Scotland and northern England.

Wind speeds of up to 100 miles an hour recorded in Scotland's wind farms helped wind power generation to rise to a provisional all-time high of more than 19,500 megawatts – or more than half the UK’s electricity – according to data from National Grid.

National Grid’s electricity system operator said that although it recognised the new milestone towards the UK’s ‘net zero’ carbon future, where wind is leading the power mix according to recent analyses, it was “also thinking of those affected by Storm Malik”.

The deadly storm caused widespread disruption over the weekend, leaving thousands without electricity and killing two people.

Many of the areas affected by Storm Malik were also hit in December by Storm Arwen, which caused the most severe disruption to power supplies since 2005, leaving almost a million homes without power for up to 12 days.

The winter storms have followed a summer of low wind power generation across the UK and Europe, even though wind produced more electricity than coal for the first time in 2016, which caused increased use of gas power plants during a global supply shortfall.

Gas markets around the world reached record highs due to rising demand for gas, and UK electricity prices hit a 10-year high as economies have rebounded from the economic shock of the Covid-19 pandemic. In the UK, electricity market prices reached an all-time high of more than £424.60 a megawatt-hour in September, compared with an average price of £44/MWh in the same month the year before.

The UK’s weekend surge in renewable electricity helped to provide a temporary reprieve from its heavy reliance on fossil fuel generation in recent months, and on some days wind has been the main source of UK electricity, which has caused market prices to reach record highs.

The market price for electricity on Saturday fell to £150.59 pounds a megawatt-hour, the lowest level since 3 January, while UK peak power prices have risen with the price for power on Sunday, when wind was expected to fall, jumping to more than £193.50/MWh.

The new wind generation record bettered a high recorded last year when the gusty May bank holiday weekend recorded 17.6GW.

 

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London Underground Power Outage Disrupts Rush Hour

London Underground Power Outage 2025 disrupted Tube lines citywide, with a National Grid voltage dip causing service suspensions, delays, and station closures; TfL recovery efforts spotlight infrastructure resilience, contingency planning, and commuter safety communications.

 

Key Points

A citywide Tube disruption on May 12, 2025, triggered by a National Grid voltage dip, exposing resilience gaps.

✅ Bakerloo, Waterloo & City, Northern suspended; Jubilee disrupted.

✅ Cause: brief National Grid fault leading to a voltage dip.

✅ TfL focuses on recovery, communication, and resilience upgrades.

 

On May 12, 2025, a significant power outage disrupted the London Underground during the afternoon rush hour, affecting thousands of commuters across the city. The incident highlighted vulnerabilities in the city's transport infrastructure, echoing a morning outage in London reported earlier, and raised concerns about the resilience of urban utilities.

The Outage and Its Immediate Impact

The power failure occurred around 2:30 PM, leading to widespread service suspensions and delays on several key Tube lines. The Bakerloo and Waterloo & City lines were completely halted, while the Jubilee line experienced disruptions between London Bridge and Finchley Road. The Northern line was also suspended between Euston and Kennington, as well as south of Stockwell. Additionally, Elizabeth Line services between Abbey Wood and Paddington were suspended. Some stations were closed for safety reasons due to the lack of power.

Commuters faced severe delays, with many stranded in tunnels or on platforms. The lack of information and communication added to the confusion, as passengers were left uncertain about the cause and duration of the disruptions.

Cause of the Power Failure

Transport for London (TfL) attributed the outage to a brief fault in the National Grid's transmission network. Although the fault was resolved within seconds, it caused a voltage dip that affected local distribution networks, leading to the power loss in the Underground system.

The incident underscored the fragility of the city's transport infrastructure, particularly the aging electrical and signaling systems that are vulnerable to such faults, as well as weather-driven events like a major windstorm outage that can trigger cascading failures. While backup systems exist, their capacity to handle sudden disruptions remains a concern.

Broader Implications for Urban Infrastructure

This power outage is part of a broader pattern of infrastructure challenges facing London. In March 2025, a fire at an electrical substation in Hayes led to the closure of Heathrow Airport, affecting over 200,000 passengers, while similar disruptions at BWI Airport have underscored aviation vulnerabilities. These incidents have prompted discussions about the resilience of the UK's energy and transport networks.

Experts argue that aging infrastructure, coupled with increasing demand and climate-related stresses, poses significant risks to urban operations, as seen in a North Seattle outage and in Toronto storm-related outages that tested local grids. There is a growing call for investment in modernization and diversification of energy sources to ensure reliability and sustainability.

TfL's Response and Recovery Efforts

Following the outage, TfL worked swiftly to restore services. By 11 PM, all but one line had resumed operations, with only the Elizabeth Line continuing to experience severe delays. TfL officials acknowledged the inconvenience caused to passengers and pledged to investigate the incident thoroughly, similar to the Atlanta airport blackout inquiry conducted after a major outage, to prevent future occurrences.

In the aftermath, TfL emphasized the importance of clear communication with passengers during disruptions and committed to enhancing its contingency planning and infrastructure resilience.

Public Reaction and Ongoing Concerns

The power outage sparked frustration among commuters, many of whom took to social media to express their dissatisfaction, echoing sentiments during Houston's extended outage about communication gaps and delays. Some passengers reported being trapped in tunnels for extended periods without clear guidance from staff.

The incident has reignited debates about the adequacy of London's transport infrastructure and the need for comprehensive upgrades. While TfL has initiated reviews and improvement plans, the public remains concerned about the potential for future disruptions and the city's preparedness to handle them.

The May 12 power outage serves as a stark reminder of the vulnerabilities inherent in urban infrastructure. As London continues to grow and modernize, ensuring the resilience of its transport and energy networks will be crucial. This includes investing in modern technologies, enhancing communication systems, and developing robust contingency plans to mitigate the impact of future disruptions. For now, Londoners are left reflecting on the lessons learned from this incident and hoping for a more reliable and resilient transport system in the future.

 

 

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