Manhole cover restraint system effective: EPRI

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Research conducted by the Electric Power Research Institute (EPRI), supports the effectiveness of a manhole cover restraint system that may prevent or limit damage caused by a manhole cover in the event of an explosion.

Manhole explosions are rare and result from various factors, but they can occur without warning. The energy released in a major manhole explosion can lift a 200-pound cast-iron cover from its frame, in some cases causing it to become airborne and posing a hazard to both life and property.

EPRI conducted the research in collaboration with two Michigan companies, Detroit Edison and Stabiloc of Warren. Stabiloc developed a controlled pressure relief mechanism, which was tested in a simulated working environment.

The cover is designed to remain engaged to the manhole frame in all but the most severe explosions. It uses two latches: a fixed latch and an adjustable breakaway latch equipped with two shear pins. In a minor explosion, the mechanism allows the cover to rise about two inches to relieve pressure and then fall back into its frame. In a more powerful explosion, the primary pin may shear, allowing the cover to rise another inch or so. In a major explosion, the secondary pin may shear to release the cover from its frame.

“EPRI’s testing confirmed that the mechanism can restrain the cover while allowing it to rise slightly to release internal pressure,” said Matt Olearczyk, manager of distribution research for EPRI. “The research team also determined the necessary pin sizes to provide controlled pressure relief and prevent roadbed damage for minor and moderate explosions.”

Detroit Edison has installed about 1,200 Stabiloc covers to enhance safety.

“This project was a landmark collaborative effort,” said Vince Dow, Detroit Edison vice president, distribution operation. “The project produced an effective, elegant solution that improves worker and public safety.

Nirmal Singh, a dielectric scientist, was Detroit Edison’s lead researcher on the project. He commented that Detroit Edison has been an EPRI member for 30 years, and, “this project stands out as a major benefit of our membership and a major benefit to our company.”

EPRI performed the analysis at its High-Voltage Laboratory facility in Lenox, Massachusetts.

EPRI and Detroit Edison researchers used a series of explosions to evaluate the performance of covers with and without the controlled pressure relief mechanism, and with various sizes of shear pins in the locking mechanism. Test results provided performance data to help the teamÂ’s engineers to optimize the coverÂ’s design.

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Mexican president's contentious electricity overhaul defeated in Congress

Mexico Energy Reform Defeat underscores opposition unity as CFE-first rules, state regulators, and lithium nationalization falter amid USMCA concerns, investment risks, and clean energy transition impacts in Congress over power generation policy.

 

Key Points

The failed push to expand CFE control, flagged for USMCA risks, higher costs, regulator shifts, and slower clean energy transition.

✅ Bill to mandate 54% CFE generation and priority dispatch failed.

✅ Opposition cited USMCA breaches, higher prices, slower clean energy.

✅ Lithium nationalization to return via separate legislation.

 

Mexican President Andres Manuel Lopez Obrador's plan to increase state control of power generation was defeated in parliament on Sunday, as opposition parties united in the face of a bill they said would hurt investment and breach international obligations, concerns mirrored by rulings such as the Florida court on electricity monopolies that scrutinize market concentration.

His National Regeneration Movement (MORENA) and its allies fell nearly 60 votes short of the two-thirds majority needed in the 500-seat lower house of Congress, mustering just 275 votes after a raucous session that lasted more than 12 hours.

Seeking to roll back previous constitutional reforms that liberalized the electricity market, Lopez Obrador's proposed changes would have done away with a requirement that state-owned Comision Federal de Electricidad (CFE) sell the cheapest electricity first, a move reminiscent of debates when energy groups warned on pricing changes under federal proposals, allowing it to sell its own electricity ahead of other power companies.

Under the bill, the CFE would also have been set to generate a minimum of 54% of the country's total electricity, and energy regulation would have been shifted from independent bodies to state regulators, paralleling concerns raised when a Calgary retailer opposed a market overhaul over regulatory impacts.

The contentious proposals faced much criticism from business groups and the United States, Mexico's top trade partner as well as other allies who argued it would violate the regional trade deal, the United States-Mexico-Canada Agreement (USMCA), even as the USA looks to Canada for green power to deepen cross-border energy ties.

Lopez Obrador had argued the bill would have protected consumers and made the country more energy independent, echoing how Texas weighs market reforms to avoid blackouts to bolster reliability, saying the legislation was vital to his plans to "transform" Mexico.

Although the odds were against his party, he came into the vote seeking to leverage his victory in last weekend's referendum on his leadership.

Speaking ahead of the vote, Jorge Alvarez Maynez, a lawmaker from the opposition Citizens' Movement party, said the proposals, if enacted, would damage Mexico, pointing to experiences like the Texas electricity market bailout after a severe winter storm as cautionary examples.

"There isn't a specialist, academic, environmentalist or activist with a smidgen of doubt - this bill would increase electricity prices, slow the transition to (clean) energy in our country and violate international agreements," he added.

Supporters of clean-energy goals noted that subnational shifts, such as the New Mexico 100% clean electricity bill can illustrate alternative pathways to reform.

The bill also contained a provision to nationalize lithium resources.

Lopez Obrador said this week that if the bill was defeated, he would send another bill to Congress on Monday aiming to have at least the lithium portion of the proposed legislation passed.

 

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Sustaining U.S. Nuclear Power And Decarbonization

Existing Nuclear Reactor Lifetime Extension sustains carbon-free electricity, supports deep decarbonization, and advances net zero climate goals by preserving the US nuclear fleet, stabilizing the grid, and complementing advanced reactors.

 

Key Points

Extending licenses keeps carbon-free nuclear online, stabilizes grid, and accelerates decarbonization toward net zero.

✅ Preserves 24/7 carbon-free baseload to meet climate targets

✅ Avoids emissions and replacement costs from premature retirements

✅ Complements advanced reactors; reduces capital and material needs

 

Nuclear power is the single largest source of carbon-free energy in the United States and currently provides nearly 20 percent of the nation’s electrical demand. As a result, many analyses have investigated the potential of future nuclear energy contributions in addressing climate change and investing in carbon-free electricity across the sector. However, few assess the value of existing nuclear power reactors.

Research led by Pacific Northwest National Laboratory (PNNL) Earth scientist Son H. Kim, with the Joint Global Change Research Institute (JGCRI), a partnership between PNNL and the University of Maryland, has added insight to the scarce literature and is the first to evaluate nuclear energy for meeting deep decarbonization goals amid rising credit risks for nuclear power identified by Moody's. Kim sought to answer the question: How much do our existing nuclear reactors contribute to the mission of meeting the country’s climate goals, both now and if their operating licenses were extended?

As the world races to discover solutions for reaching net zero as part of the global energy transition now underway, Kim’s report quantifies the economic value of bringing the existing nuclear fleet into the year 2100. It outlines its significant contributions to limiting global warming.

Plants slated to close by 2050 could be among the most important players in a challenge requiring all available carbon-free technology solutions—emerging and existing—alongside renewable electricity in many regions, the report finds. New nuclear technology also has a part to play, and its contributions could be boosted by driving down construction costs.  

“Even modest reductions in capital costs could bring big climate benefits,” said Kim. “Significant effort has been incorporated into the design of advanced reactors to reduce the use of all materials in general, such as concrete and steel because that directly translates into reduced costs and carbon emissions.”

Nuclear power reactors face an uncertain future, and some utilities face investor pressure to release climate reports as well.
The nuclear power fleet in the United States consists of 93 operating reactors across 28 states. Most of these plants were constructed and deployed between 1970-1990. Half of the fleet has outlived its original operating license lifetime of 40 years. While most reactors have had their licenses renewed for an additional 20 years, and some for another 20, the total number of reactors that will receive a lifetime extension to operate a full 80 years from deployment is uncertain.

Other countries also rely on nuclear energy. In France, for example, nuclear energy provides 70 percent of the country’s power supply. They and other countries must also consider extending the lifetime, retiring, or building new, modern reactors while navigating Canadian climate policy implications for electricity grids. However, the U.S. faces the potential retirement of many reactors in a short period—this could have a far stronger impact than the staggered closures other countries may experience.

“Our existing nuclear power plants are aging, and with their current 60-year lifetimes, nearly all of them will be gone by 2050. It’s ironic. We have a net zero goal to reach by 2050, yet our single largest source of carbon-free electricity is at risk of closure, as seen in New Zealand's electricity transition debates,“ said Kim.

 

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Tube Strikes Disrupt London Economy

London Tube Strikes Economic Impact highlights transport disruption reducing foot traffic, commuter flows, and tourism, squeezing small businesses, hospitality revenue, and citywide growth while business leaders urge negotiations, resolution, and policy responses to stabilize operations.

 

Key Points

Reduced transport options cut foot traffic and sales, straining small businesses and slowing London-wide growth.

✅ Hospitality venues report lower revenue and temporary closures

✅ Commuter and tourism declines reduce daily sales and bookings

✅ Business groups urge swift negotiations to restore services

 

London's economy is facing significant challenges due to ongoing tube strikes, challenges that are compounded by scrutiny of UK energy network profits and broader cost pressures across sectors, with businesses across the city experiencing disruptions that are impacting their operations and bottom lines.

Impact on Small Businesses

Small businesses, particularly those in the hospitality sector, are bearing the brunt of the disruptions caused by the strikes. Many establishments rely on the steady flow of commuters and tourists that the tube system facilitates, while also hoping for measures like temporary electricity bill relief that can ease operating costs during downturns. With reduced transportation options, foot traffic has dwindled, leading to decreased sales and, in some cases, temporary closures.

Economic Consequences

The strikes are not only affecting individual businesses but are also having a ripple effect on the broader economy, a dynamic seen when commercial electricity consumption plummeted in B.C. during the pandemic. The reduced activity in key sectors is contributing to a slowdown in economic growth, echoing periods when BC Hydro demand fell 10% and prompting policy responses such as Ontario electricity rate reductions for businesses, with potential long-term consequences if the disruptions continue.

Calls for Resolution

Business leaders and industry groups are urging for a swift resolution to the strikes. They emphasize the need for dialogue between the involved parties to reach an agreement that minimizes further economic damage and restores normalcy to the city's transportation system.

The ongoing tube strikes in London are causing significant disruptions to the city's economy, particularly affecting small businesses that depend on the efficient movement of people. Immediate action is needed to address the issues, drawing on tools like a subsidized hydro plan used elsewhere to spur recovery, to prevent further economic downturn.

 

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BC announces grid development, job creation

BC Hydro Power Pathway accelerates electrification with clean energy investments, new transmission lines, upgraded substations, and renewable projects like wind and solar, strengthening the grid, supporting decarbonization, and creating jobs across British Columbia's growing economy.

 

Key Points

A $36B, 10-year BC Hydro plan to expand clean power infrastructure, accelerate electrification, and support jobs.

✅ $36B for new lines, substations, dam upgrades, and distribution

✅ Supports 10,500-12,500 jobs per year across B.C.

✅ Adds wind and solar, leveraging hydro to balance renewables

 

BC Hydro is gearing up for a decade of extensive construction to enhance British Columbia's electrical system, supporting a burgeoning clean economy and community growth while generating new employment opportunities.

Premier David Eby emphasized the necessity of expanding the electrical system for industrial growth, residential needs, and future advancements. He highlighted the role of clean, affordable energy in reducing pollution, securing well-paying jobs, and fostering economic growth.

At the B.C. Natural Resources Forum in Prince George, Premier Eby unveiled a $36-billion investment plan for infrastructure projects in communities and regions and green energy solutions to provide clean, affordable electricity for future generations.

The Power Pathway: Building BC’s Energy Future, BC Hydro’s revised 10-year capital plan, involves nearly $36 billion in investments across the province from 2024-25 to 2033-34. This marks a 50% increase from the previous plan of $24 billion and includes a substantial rise in electrification and emissions-reduction projects (nearly $10 billion, up from $1 billion).

These upcoming construction projects are expected to support approximately 10,500 to 12,500 jobs annually. The plan is set to bolster and sustain BC Hydro’s capital investments as significant projects like Site C are near completion.

The plan addresses the increasing demand for electricity due to population and housing growth, industrial development, such as a major hydrogen project, and the transition from fossil fuels to clean electricity. Key projects include constructing new high-voltage transmission lines from Prince George to Terrace, building or expanding substations in high-growth areas, and upgrading dams and generating facilities for enhanced safety and efficiency.

Minister of Energy, Mines, and Low Carbon Innovation Josie Osborne stated that this plan aims to build a clean energy future and support EV charging expansion while creating construction jobs. With BC Hydro’s capital plan allocating almost $4 billion annually for the next decade, it will drive economic growth and ensure access to clean, affordable electricity.

BC Hydro aims to add new clean, renewable energy sources like wind and solar, while acknowledging power supply challenges that must be managed as capacity grows. B.C.’s hydroelectric dams, functioning as batteries, enable the integration of intermittent renewables into the grid, providing reliable backup.

Chris O’Riley, president and CEO of BC Hydro, said the grid is one of the world’s cleanest. The new $36 billion capital plan encompasses investments in generation assets, large transmission infrastructure, and local distribution networks.

In partnership with BC Hydro, Premier Eby also announced a new streamlined approval process to expedite electrification for high-demand industries and support job creation, complementing measures like the BC Hydro rebate and B.C. Affordability Credit that help households.

Minister of Environment and Climate Change Strategy George Heyman highlighted the importance of rapid electrification in collaboration with the private sector to achieve CleanBC climate goals by 2030, including corridor charging via the BC's Electric Highway, and maintain the competitiveness of B.C. industries. The new process will streamline approvals for industrial electrification projects, enhancing efficiency and funding certainty.

 

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How Ukraine Unplugged from Russia and Joined Europe's Power Grid with Unprecedented Speed

Ukraine-ENTSO-E Grid Synchronization links Ukraine and Moldova to the European grid via secure interconnection, matching frequency for stability, resilience, and energy security, enabling cross-border support, islanding recovery, and coordinated load balancing during wartime disruptions.

 

Key Points

Rapid alignment of Ukraine and Moldova into the European grid to enable secure interconnection and system stability.

✅ Matches 50 Hz frequency across interconnected systems

✅ Enables cross-border support and electricity trading

✅ Improves resilience, stability, and energy security

 

On February 24 Ukraine’s electric grid operator disconnected the country’s power system from the larger Russian-operated network to which it had always been linked. The long-planned disconnection was meant to be a 72-hour trial proving that Ukraine could operate on its own and to protect electricity supply before winter as contingencies were tested. The test was a requirement for eventually linking with the European grid, which Ukraine had been working toward since 2017. But four hours after the exercise started, Russia invaded.

Ukraine’s connection to Europe—which was not supposed to occur until 2023—became urgent, and engineers aimed to safely achieve it in just a matter of weeks. On March 16 they reached the key milestone of synchronizing the two systems. It was “a year’s work in two weeks,” according to a statement by Kadri Simson, the European Union commissioner for energy. That is unusual in this field. “For [power grid operators] to move this quickly and with such agility is unprecedented,” says Paul Deane, an energy policy researcher at the University College Cork in Ireland. “No power system has ever synchronized this quickly before.”

Ukraine initiated the process of joining Europe’s grid in 2005 and began working toward that goal in earnest in 2017, as did Moldova. It was part of an ongoing effort to align with Europe, as seen in the Baltic states’ disconnection from the Russian grid, and decrease reliance on Russia, which had repeatedly threatened Ukraine’s sovereignty. “Ukraine simply wanted to decouple from Russian dominance in every sense of the word, and the grid is part of that,” says Suriya Jayanti, an Eastern European policy expert and former U.S. diplomat who served as energy chief at the U.S. embassy in Kyiv from 2018 to 2020.

After the late February trial period, Ukrenergo, the Ukrainian grid operator, had intended to temporarily rejoin the system that powers Russia and Belarus. But the Russian invasion made that untenable. “That left Ukraine in isolation mode, which would be incredibly dangerous from a power supply perspective,” Jayanti says. “It means that there’s nowhere for Ukraine to import electricity from. It’s an orphan.” That was a particularly precarious situation given Russian attacks on key energy infrastructure such as the Zaporizhzhia nuclear power plant and ongoing strikes on Ukraine’s power grid that posed continuing risks. (According to Jayanti, Ukraine’s grid was ultimately able to run alone for as long as it did because power demand dropped by about a third as Ukrainians fled the country.)

Three days after the invasion, Ukrenergo sent a letter to the European Network of Transmission System Operators for Electricity (ENTSO-E) requesting authorization to connect to the European grid early. Moldelectrica, the Moldovan operator, made the same request the following day. While European operators wanted to support Ukraine, they had to protect their own grids, amid renewed focus on protecting the U.S. power grid from Russian hacking, so the emergency connection process had to be done carefully. “Utilities and system operators are notoriously risk-averse because the job is to keep the lights on, to keep everyone safe,” says Laura Mehigan, an energy researcher at University College Cork.

An electric grid is a network of power-generating sources and transmission infrastructure that produces electricity and carries it from places such as power plants, wind farms and solar arrays to houses, hospitals and public transit systems. “You can’t just experiment with a power system and hope that it works,” Deane says. Getting power where it is it needed when it is needed is an intricate process, and there is little room for error, as incidents involving Russian hackers targeting U.S. utilities have highlighted for operators worldwide.

Crucial to this mission is grid interconnection. Linked systems can share electricity across vast areas, often using HVDC technology, so that a surplus of energy generated in one location can meet demand in another. “More interconnection means we can move power around more quickly, more efficiently, more cost effectively and take advantage of low-carbon or zero-carbon power sources,” says James Glynn, a senior research scholar at the Center on Global Energy Policy at Columbia University. But connecting these massive networks with many moving parts is no small order.

One of the primary challenges of interconnecting grids is synchronizing them, which is what Ukrenergo, Moldelectrica and ENTSO-E accomplished last week. Synchronization is essential for sharing electricity. The task involves aligning the frequencies of every energy-generation facility in the connecting systems. Frequency is like the heartbeat of the electric grid. Across Europe, energy-generating turbines spin 50 times per second in near-perfect unison, and when disputes disrupt that balance, slow clocks across Europe can result, reminding operators of the stakes. For Ukraine and Moldova to join in, their systems had to be adjusted to match that rhythm. “We can’t stop the power system for an hour and then try to synchronize,” Deane says. “This has to be done while the system is operating.” It is like jumping onto a moving train or a spinning ride at the playground: the train or ride is not stopping, so you had better time the jump perfectly.

 

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Enel kicks off 90MW Spanish wind build

Enel Green Power España Aragon wind farms advance Spain's renewable energy transition, with 90MW under construction in Teruel, Endesa investment of €88 million, 25-50MW turbines, and 2017 auction-backed capacity enhancing grid integration and clean power.

 

Key Points

They are three Teruel wind projects totaling 90MW, part of Endesa's 2017-awarded plan expanding Spain's clean energy.

✅ 90MW across Sierra Costera I, Allueva, and Sierra Pelarda

✅ €88m invested; 14+7+4 turbines; Endesa-led build in Teruel

✅ Part of 2017 tender: 540MW wind, 339MW solar, nationwide

 

Enel Green Power Espana, part of Enel's wind projects worldwide, has started constructing three wind farms in Aragon, north-east Spain, which are due online by the end of the year.

The projects, all situated in the Teruel province, are worth a total investment of €88 million.

The biggest of the facilities, Sierra Costera I, will have a 50MW and will feature 14 turbines.

The wind farm is spread across the municipalities of Mezquita de Jarque, Fuentes Calientes, Canada Vellida and Rillo.

The Allueva wind facility will feature seven turbines and will exceed 25MW.

Sierra Pelarda, in Fonfria, will have four turbines and a capacity of 15MW, as advances in offshore wind turbine technology continue to push scale elsewhere.

The projects bring the total number of wind farms that Enel Green Power Espana has started building in the Teruel province to six, equal to an overall capacity of 218MW.

Endesa chief executive Jose Bogas said: “These plants mark the acceleration on a new wave of growth in the renewable energy space that Endesa is committed to pursue in the next years, driving the energy transition in Spain.”

The six wind farms under construction in Teruel are part of the 540MW that Enel Green Power Espana was awarded in the Spanish government's renewable energy tender held in May 2017.

In Aragon, the company will invest around €434 million euros, reflecting broader European wind power investment trends in recent years, to build 13 wind farms with a total installed capacity of more than 380MW.

The remaining 160MW of wind capacity will be located in Andalusia, Castile-Leon, Castile La Mancha and Galicia, even as some Spanish turbine factories closed during pandemic restrictions.

Enel Green Power Espana was also awarded 339MW of solar capacity in the Spanish government's auction held in July 2017, while other Spanish developers advance CSP projects abroad in markets like Chile.

Once all wind and solar under the 2017 tender are complete they will boost the company’s capacity by around 52%.

 

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