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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California Utility Cuts Power to Massive Areas in Northern, Central California

PG&E Public Safety Power Shutoff curbs wildfire risk amid high winds, triggering California outages across Northern California and Bay Area counties; grid safety measures, outage maps, campus closures, and restoration timelines guide residents and businesses.

 

Key Points

A preemptive outage program by PG&E to reduce wildfire ignition during extreme wind events in California.

✅ Cuts power during red flag, high wind, dry fuel conditions

✅ Targets Northern California, Bay Area counties at highest risk

✅ Restoration follows inspections, weather all-clear, hazard checks

 

California utility Pacific Gas and Electric Co. (PG&E) has cut off power supply to hundreds of thousands of residents in Northern and Central California as a precaution to possible breakout of wildfires, a move examined in reasons for shutdowns by industry observers.

PG&E confirmed that about 513,000 customers in many counties in Northern California, including Napa, Sierra, Sonoma and Yuba, were affected in the first phase of Public Safety Power Shutoff, a preemptive measure it took to prevent wildfires believed likely to be triggered by strong, dry winds.

The utility said the decision to shut off power was, amid ongoing debate over nuclear's status in California, "based on forecasts of dry, hot and windy weather including potential fire risk."

"This weather event will last through midday Thursday, with peak winds forecast from Wednesday morning through Thursday morning and reaching 60 mph (about 96 km per hour) to 70 mph (about 112 km per hour) at higher elevations," it said, while abroad National Grid warnings about short supply have highlighted parallel reliability concerns.

PG&E noted that about 234,000 residents in mostly counties of San Francisco Bay Area such as Alameda, Alpine, Contra Costa, San Mateo and Santa Clara were impacted in the second phase of the power shutoff, as the state considers power plant closure delays with potential grid impacts, that began around noon in Wednesday.

The unprecedented power outages sweeping across Northern California has darkened homes and forced schools and business to close, even as the UK paused an emergency energy plan amid its own supply concerns.

University of California, Berkeley canceled all classes for Wednesday due to expected campus power loss over the next few days.

The university said it has received notice from PG&E, as China's power woes cloud U.S. solar supplies that could aid resilience, that "most of the core campus will be without power" possibly for 48 hours.

A freshman at California State University San Jose told Xinhua that their classes were canceled Wednesday as the campus was running out of power.

"I had to go home because even our dormitory went without electricity," the student added.

However, PG&E noted in an updated statement Wednesday night that only 4,000 customers would be affected in the third phase being considered for Kern County in Central California, compared to an earlier forecast of 43,000 people who would experience power outage.

The PG&E power shutoff was the largest preemptive measure ever taken to prevent wildfires in the state's history, and it comes as clean power grows while fossil declines across California's grid, highlighting broader transition challenges.

The San Francisco-based California utility was held responsible for poor management of its power lines that sparked fatal wildfires in Northern California and killed 86 people last year in what was called Camp Fire, the single-deadliest wildfire in California's history.

Several lawsuits and other requests for compensation from wildfire victims that amounted to billions of U.S. dollars forced the embattled the company to claim bankruptcy protection early this year.

 

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B.C. electricity demand hits an all-time high

BC Hydro Peak Electricity Demand reached a record 10,902 megawatts during a cold snap, driven by home heating. Peak hours surged; load shifting and energy conservation can ease strain on the grid and lower bills.

 

Key Points

Record winter peak of 10,902 MW, set during a cold snap, largely from home heating demand at peak hours.

✅ All-time high load: 10,902 MW between 5 and 6 p.m., Dec. 27.

✅ Cold snap increased home heating demand during peak hours.

✅ Shift laundry and dishwashers off-peak; use programmable thermostats.

 

BC Hydro says the province set a new record for peak electricity demand on Monday as temperatures hit extreme lows, and Quebec shattered consumption records during similar cold weather.

Between 5 and 6 p.m. on Dec. 27, demand for electricity hit an all-time high of 10,902 megawatts, which is higher than the previous record of 10,577 megawatts set in 2020, and follows a record-breaking year in 2021 for the utility.

“The record represents a single moment in the hour when demand for electricity was the highest yesterday,” says Simi Heer, BC Hydro spokesperson, in a statement. “Most of the increase is likely due to additional home heating required during this cold snap.”

In addition to the peak demand record on Monday, BC Hydro has observed an overall increase in electricity demand since Friday, and has noted that cryptocurrency mining electricity use is an emerging load in the province as well. Monday’s hourly peak demand was 18 per cent higher than Friday’s, while Calgary's electricity use soared during a frigid February, underscoring how cold snaps strain regional grids.

“BC Hydro has enough supply options in place to meet increasing electricity demand,” adds Heer, and pointed to customer supports like a winter payment plan for households managing higher bills. “However, if British Columbians want to help ease some of the demand on the system during peak times, we encourage shifting activities like doing laundry or running dishwashers to earlier in the day or later in the evening.”

BC Hydro is also offering energy conservation tips for people looking to lower their electricity use and their electricity bills, noting that Earth Hour once saw electricity use rise in the province:

Manage your home heating actively by turning the heat down when no one his home or when everyone is sleeping. Consider installing a programmable thermostat to automatically adjust temperatures at different times based on your family's activities, and remember that in warmer months wasteful air conditioning can add $200 to summer energy bills. BC Hydro recommends the following temperatures:

16 degrees Celsius when sleeping or away from home
21 degrees Celsius when relaxing, watching TV
18 degrees Celsius when doing housework or cleaning
 

 

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Gaza’s sole electricity plant shuts down after running out of fuel

Gaza Power Plant Shutdown underscores the Gaza Strip's fuel ban, Israeli blockade, and electricity crisis, cutting megawatts, disrupting hospitals and quarantine centers, and exposing fragile energy supply, GEDCO warnings, and public health risks.

 

Key Points

An abrupt halt of Gaza's sole power plant due to a fuel ban, deepening the electricity crisis and straining hospitals.

✅ Israeli fuel ban halts Gaza's only power plant

✅ Available supply drops far below 500 MW demand

✅ Hospitals and COVID-19 quarantine centers at risk

 

The only electricity plant in the Gaza Strip shut down yesterday after running out of fuel banned from entering the besieged enclave by the Israeli occupation, Gaza Electricity Distribution Company announced.

“The power plant has shut down completely,” the company said in a brief statement, as disruptions like China power cuts reveal broader grid vulnerabilities.

Israel banned fuel imports into Gaza as part of punitive measures over the launching incendiary balloons from the Strip.

On Sunday, GEDCO warned that the industrial fuel for the electricity plant would run out, mirroring Lebanon's fuel shortage challenges, on Tuesday morning.

Since 2007, the Gaza Strip suffered under a crippling Israeli blockade that has deprived its roughly two million inhabitants of many vital commodities, including food, fuel and medicine, and regional strains such as Iraq's summer electricity needs highlight broader power insecurity.

As a result, the coastal enclave has been reeling from an electricity crisis, similar to when the National Grid warned of short supply in other contexts.

The Gaza Strip needs some 500 megawatts of electricity – of which only 180 megawatts are currently available – to meet the needs of its population, while Iran supplies about 40% of Iraq's electricity in the region.

Spokesman of the Ministry of Health in Gaza, Ashraf Al Qidra, said the lack of electricity undermines offering health services across Gaza’s hospitals.

He also warned that the lack of electricity would affect the quarantine centres used for coronavirus patients, reinforcing the need to keep electricity options open during the pandemic.

Gaza currently has three sources of electricity: Israel, which provides 120 megawatts and is advancing coal use reduction measures; Egypt, which supplies 32 megawatts; and the Strip’s sole power plant, which generates between 40 and 60 megawatts.

 

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California Welcomes 70 Volvo VNR Electric Trucks

Switch-On Project Electric Trucks accelerate California freight decarbonization, deploying Volvo VNR Electric rigs with high-capacity charging infrastructure, zero-emissions operations, and connected safety features to cut greenhouse gases and improve urban air quality.

 

Key Points

A California program deploying Volvo VNR Electric trucks and charging to decarbonize freight and improve air quality.

✅ 70 Volvo VNR Electric trucks for regional logistics

✅ Strategic high-capacity charging for heavy-duty fleets

✅ Lower TCO via fuel savings and reduced maintenance

 

In a significant step toward sustainable transportation, the Switch-On project is bringing 70 Volvo VNR Electric trucks to California. This initiative aims to bolster the state's efforts to reduce emissions and transition to greener logistics solutions. The arrival of these electric vehicles marks an important milestone in California's commitment to combating climate change and improving air quality.

The Switch-On Project: Overview and Goals

The Switch-On project is a collaborative effort designed to enhance electric truck adoption in California. It focuses on developing the necessary infrastructure and technology to support electric vehicles (EVs) in the freight and logistics sectors, building on recent nonprofit investments at California ports. The project not only seeks to increase the availability of electric trucks but also aims to demonstrate their effectiveness in real-world applications.

California has set ambitious goals for reducing greenhouse gas emissions, particularly from the transportation sector, which is one of the largest contributors to air pollution. By introducing electric trucks into freight operations, the state aims to significantly cut emissions, improve public health, and pave the way for a more sustainable future.

The Volvo VNR Electric Trucks

The Volvo VNR Electric trucks are specifically designed for regional distribution and urban transport, aligning with Volvo's broader electric lineup as the company expands offerings, making them ideal for the needs of California’s freight industry. With a range of approximately 250 miles on a single charge, these trucks can efficiently handle most regional routes. Equipped with advanced technology, including regenerative braking and connectivity features, the VNR Electric models enhance operational efficiency and safety.

These trucks not only provide a cleaner alternative to traditional diesel vehicles but also promise lower operational costs over time. With reduced fuel expenses and lower maintenance needs, and emerging vehicle-to-grid pilots that can create new value streams, businesses can benefit from significant savings while contributing to environmental sustainability.

Infrastructure Development

A crucial aspect of the Switch-On project is the development of charging infrastructure to support the new fleet of electric trucks. The project partners are working on installing high-capacity charging stations strategically located throughout California while addressing utility planning challenges that large fleets will pose to the power system. This infrastructure is essential to ensure that electric trucks can be charged efficiently, minimizing downtime and maximizing productivity.

The charging stations are designed to accommodate the specific needs of heavy-duty vehicles, and corridor models like BC's Electric Highway provide useful precedents for network design, allowing for rapid charging that aligns with operational schedules. This development not only supports the new fleet but also encourages other logistics companies to consider electric trucks as a viable option for their operations.

Benefits to California

The introduction of 70 Volvo VNR Electric trucks will have several positive impacts on California. Firstly, it will significantly reduce greenhouse gas emissions from the freight sector, contributing to the state’s ambitious climate goals even as grid expansion will be needed to support widespread electrification across sectors. The transition to electric trucks is expected to improve air quality, particularly in urban areas that struggle with high pollution levels.

Moreover, the project serves as a model for other regions considering similar initiatives. By showcasing the practicality and benefits of electric trucks, California hopes to inspire widespread adoption across the nation. As the market for electric vehicles continues to grow, this project can play a pivotal role in accelerating the transition to sustainable transportation solutions.

Industry and Community Reactions

The arrival of the Volvo VNR Electric trucks has been met with enthusiasm from both industry stakeholders and community members. Logistics companies are excited about the opportunity to reduce their carbon footprints and operational costs. Meanwhile, environmental advocates applaud the project as a crucial step toward cleaner air and healthier communities.

California’s commitment to sustainable transportation has positioned it as a leader in the shift to electric vehicles amid an ongoing biofuels vs. EVs debate over the best path forward, setting an example for other states and countries.

Conclusion

The Switch-On project represents a major advancement in California's efforts to transition to electric transportation. With the deployment of 70 Volvo VNR Electric trucks, the state is not only taking a significant step toward reducing emissions but also demonstrating the feasibility of electric logistics solutions.

As infrastructure develops and more electric trucks hit the roads, California is paving the way for a greener, more sustainable future in transportation. The success of this project could have far-reaching implications, influencing policies and practices in the broader freight industry and beyond.

 

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UK peak power prices rise to second highest level since 2018

UK Peak Power Prices surged as low wind speeds forced National Grid to rely on gas-fired plants and coal generation, amid soaring wholesale gas prices and weak wind generation during the energy crisis.

 

Key Points

UK Peak Power Prices are electricity costs at peak hours, driven by wind output, gas reliance, and market dynamics.

✅ Spikes when wind generation drops and demand rises.

✅ Driven by gas-fired plants, coal backup, and wholesale gas prices.

✅ Moderate as wind output recovers and interconnectors supply.

 

Low wind speeds pushed peak hour power prices to the second highest level for at least three years on Monday, a move consistent with UK electricity prices hitting a 10-year high earlier this year, as Britain’s grid was forced to increase its reliance on gas-fired power plants and draw on coal generation.

Calm weather this year has exacerbated the energy price crisis in the UK, as gas-fired power stations have had to pick up the slack from wind farms. Energy demand has surged as countries open up from pandemic restrictions, which together with lower supplies from Russia to western Europe, has sent wholesale gas prices soaring.

Power prices in the UK for the peak evening period between 5pm and 6pm on Monday surpassed £2,000 per megawatt hour, only the second time they have exceeded that level in recent years.

This was still below the levels reached at the height of the gas price crisis in mid-September, when they hit £2,500/MWh, according to the energy consultancy Cornwall Insight, whose records date back to 2018.

Low wind speeds were the main driver behind Monday’s price spike, although expectations of a pick-up in wind generation on Tuesday, after recent record wind generation days, should push them back down to similar levels seen in recent weeks, analysts said.

Despite the expansion of renewables, such as wind and solar, over the past decade, with instances of wind leading the power mix in recent months, gas remains the single biggest source of electricity generation in Britain, typically accounting for nearly 40 per cent of output.

At lunchtime on Monday, gas-fired power plants were producing nearly 55 per cent of electricity, while coal accounted for 3 per cent, reflecting more power from wind than coal in 2016 milestones. Britain’s wind farms were contributing 1.67 gigawatts or just over 4 per cent, according to data from the Drax Electrics Insights website. Over the past 12 months, wind farms have produced 21 per cent of the UK’s electricity on average.

National Grid, which manages the UK’s electricity grid, has been forced on a number of occasions in recent months to ask coal plants to fire up to help offset the loss of wind generation, after issuing a National Grid short supply warning to the market. The government announced in June that it planned to bring forward the closure of the remaining coal stations to the end of September 2024.

Ministers also committed this year to making Britain’s electricity grid “net zero carbon” by 2035, and milestones such as when wind was the main source underline the transition, although some analysts have pointed out that would not signal the end of gas generation.

Since the start of the energy crisis in August, 20 energy suppliers have gone bust as they have struggled to secure the electricity and gas needed to supply customers at record wholesale prices, with further failures expected in coming weeks.

Phil Hewitt, director of the consultancy EnAppSys, said Monday’s high prices would further exacerbate pressures on those energy suppliers that do not have adequate hedging strategies. “This winter is a good time to be a generator,” he added.

Energy companies including Orsted of Denmark and SSE of the UK have reported some of the lowest wind speeds for at least two decades this year, even though record output during Storm Malik highlighted the system's volatility.

According to weather modelling group Vortex, the strength of the wind blowing across northern Europe has fallen by as much as 15 per cent on average in places this year, which some scientists suggest could be due to climate change.
 

 

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National Grid warns of short supply of electricity over next few days

National Grid power supply warning highlights electricity shortage risks amid low wind output, generator outages, and cold weather, reducing capacity margins and grid stability; considering demand response and reserve power to avoid blackout risk.

 

Key Points

An alert that reduced capacity from low wind and outages requires actions to maintain UK grid stability.

✅ Low wind output and generator outages reduce capacity margins

✅ ESO exploring demand response and reserve generation options

✅ Aim: maintain grid stability and avoid blackout risk

 

National Grid has warned that Britain’s electricity will be in short supply over the next few days after a string of unplanned power plant outages and unusually low wind speeds this week, as cheap wind power wanes across the system.

The electricity system operator said it will take action to “make sure there is enough generation” during the cold weather spell, including virtual power plants and other demand-side measures, to prevent a second major blackout in as many years.

“Unusually low wind output coinciding with a number of generator outages means the cushion of spare capacity we operate the system with has been reduced,” the company told its Twitter followers.

“We’re exploring measures and actions to make sure there is enough generation available to increase our buffer of capacity.”

A spokeswoman for National Grid said the latest electricity supply squeeze was not expected to be as severe as recorded last month, following reports that the government’s emergency energy plan was not going ahead, and added that the company did not expect to issue an official warning in the next 24 hours.

“We’re monitoring how the situation develops,” she said.

The warning is the second from the electricity system operator in recent weeks. In mid-September the company issued an official warning to the electricity market as peak power prices climbed, that its ‘buffer’ of power reserves had fallen below 500MW and it may need to call on more power plants to help prevent a blackout. The notice was later withdrawn.

Concerns over National Grid’s electricity supplies have been relatively rare in recent years. It was forced in November 2015 to ask businesses to cut their demand as a “last resort” measure to keep the lights on after a string of coal plant breakdowns.

But since then, National Grid’s greater challenge has been an oversupply of electricity, partly due to record wind generation, which has threatened to overwhelm the grid during times of low electricity demand.

National Grid has already spent almost £1bn on extra measures to prevent blackouts over the first half of the year by paying generators to produce less electricity during the coronavirus lockdown, as daily demand fell.

The company paid wind farms to turn off, and EDF Energy to halve the nuclear generation from its Sizewell B nuclear plant, to avoid overwhelming the grid when demand for electricity fell by almost a quarter from last year.

The electricity supply squeeze comes a little over a year after National Grid left large parts of England and Wales without electricity after the biggest blackout in a decade left a million homes in the dark. National Grid blamed a lightning strike for the widespread power failure.

Similar supply strains have recently caused power cuts in China, underscoring how weather and generation mix can trigger blackouts.

 

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