Manhole cover restraint system effective: EPRI

By Electricity Forum


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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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COVID-19 Pandemic Puts $35 Billion in Wind Energy Investments at Risk, Says Industry Group

COVID-19 Impact on U.S. Wind Industry: disrupting wind power projects, tax credits, and construction timelines, risking rural revenues, jobs, and $35B investments; AWEA seeks Congressional flexibility as OEM shutdowns like Siemens Gamesa intensify delays.

 

Key Points

Pandemic disruptions threaten 25 GW of projects, $35B investment, rural revenues, jobs, and tax-credit timelines.

✅ 25 GW at risk; $35B investment jeopardized

✅ Rural taxes and land-lease payments may drop $8B

✅ AWEA seeks Congressional flexibility on tax-credit deadlines

 

In one of the latest examples of the havoc that the novel coronavirus is wreaking on the U.S. economy and the crisis hitting solar and wind sector alike, the American Wind Energy Association (AWEA) -- the national trade association for the U.S. wind industry -- yesterday stated its concerns that COVID-19 will "pose significant challenges to the American wind power industry." According to AWEA's calculations, the disease is jeopardizing the development of approximately 25 gigawatts of wind projects, representing $35 billion in investments, even as wind additions persist in some markets amid the pandemic.

Rural communities, where about 99% of wind projects are located, in particular, face considerable risk. The AWEA estimates that rural communities stand to lose about $8 billion in state and local tax payments and land-lease payments to private landowners. In addition, it's estimated that the pandemic threatens the loss of over 35,000 jobs, and the U.S. wind jobs outlook underscores the stakes, including wind turbine technicians, construction workers, and factory workers.

The development of wind projects is heavily reliant on the earning of tax credits, and debates over a Solar ITC extension highlight potential impacts on wind. However, in order to qualify for the current credits, project developers are bound to begin construction before Dec. 31, 2020. With local and state governments implementing various measures to stop the spread of the virus, the success of project developers' meeting this deadline is dubious, as utility-scale solar construction slows nationwide due to COVID-19. Addressing this and other challenges, the AWEA is turning to the government for help. In the trade association's press release, it states that "to protect the industry and these workers, AWEA is asking Congress for flexibility in allowing existing policies to continue working for the industry through this period of uncertainty."

Illustrating one of the ways in which COVID-19 is affecting the industry, Siemens Gamesa, a global leader in the manufacturing of wind turbines, closed a second Spanish factory this week after learning that a second of its employees had tested positive for the novel coronavirus.

 

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Prevent Summer Power Outages

Summer Heatwave Electricity Shutoffs strain utilities and vulnerable communities, highlighting energy assistance, utility moratoriums, cooling centers, demand response, and grid resilience amid extreme heat, climate change, and rising air conditioning loads.

 

Key Points

Service disconnections for unpaid bills during extreme heat, risking vulnerable households and straining power grids.

✅ Moratoriums and flexible payment plans reduce shutoff risk.

✅ Cooling centers and assistance programs protect at-risk residents.

✅ Demand response, smart grids, and efficiency ease peak loads.

 

As summer temperatures soar, millions of people across the United States face the grim prospect of electricity shutoffs due to unpaid bills, as heat exacerbates electricity struggles for many families nationwide. This predicament highlights a critical issue exacerbated by extreme weather conditions and economic disparities.

The Challenge of Summer Heatwaves

Summer heatwaves not only strain power grids, as unprecedented electricity demand has shown, but also intensify energy consumption as households and businesses crank up their air conditioning units. This surge in demand places considerable stress on utilities, particularly in regions unaccustomed to prolonged heatwaves or lacking adequate infrastructure to cope with increased loads.

Vulnerable Populations

The threat of electricity shutoffs disproportionately affects vulnerable populations, including low-income households who face sky-high energy bills during extreme heat, elderly individuals, and those with underlying health conditions. Lack of access to air conditioning during extreme heat can lead to heat-related illnesses such as heat exhaustion and heatstroke, posing serious health risks.

Economic and Social Implications

The economic impact of electricity shutoffs extends beyond immediate discomfort, affecting productivity, food storage, and the ability to work remotely for those reliant on electronic devices, while rising electricity prices further strain household budgets. Socially, the inability to cool homes and maintain basic comforts strains community resilience and exacerbates inequalities.

Policy and Community Responses

In response to these challenges, policymakers and community organizations advocate for measures to prevent electricity shutoffs during heatwaves. Proposed solutions include extending moratoriums on shutoffs, informed by lessons from COVID-19 energy insecurity measures, implementing flexible payment plans, providing financial assistance to at-risk households, and enhancing communication about available resources.

Public Awareness and Preparedness

Raising public awareness about energy conservation during peak hours and promoting strategies to stay cool without overreliance on air conditioning are crucial steps towards mitigating electricity demand. Encouraging energy-efficient practices and investing in renewable energy sources also contribute to long-term resilience against climate-driven energy challenges.

Collaborative Efforts

Collaboration between government agencies, utilities, nonprofits, and community groups is essential in developing comprehensive strategies to safeguard vulnerable populations during heatwaves, especially when systems like the Texas power grid face renewed stress during prolonged heatwaves. By pooling resources and expertise, stakeholders can better coordinate emergency response efforts, distribute cooling centers, and ensure timely assistance to those in need.

Technology and Innovation

Advancements in smart grid technology and decentralized energy solutions offer promising avenues for enhancing grid resilience and minimizing disruptions during extreme weather events. These innovations enable more efficient energy management, demand response programs, and proactive monitoring of grid stability, though some utilities face summer supply-chain constraints that delay deployments.

Conclusion

As summer heatwaves become more frequent and severe, the risk of electricity shutoffs underscores the urgent need for proactive measures to protect vulnerable communities. By prioritizing equity, sustainability, and resilience in energy policy and practice, stakeholders can work towards ensuring reliable access to electricity, particularly during times of heightened climate vulnerability. Addressing these challenges requires collective action and a commitment to fostering inclusive and sustainable solutions that prioritize human well-being amid changing climate realities.

 

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Cost, safety drive line-burying decisions at Tucson Electric Power

TEP Undergrounding Policy prioritizes selective underground power lines to manage wildfire risk, engineering costs, and ratepayer impacts, balancing transmission and distribution reliability with right-of-way, safety, and vegetation management per Arizona regulators.

 

Key Points

A selective TEP approach to bury lines where safety, engineering, and cost justify undergrounding.

✅ Selective undergrounding for feeders near substations

✅ Balances wildfire mitigation, reliability, and ratepayer costs

✅ Follows ACC rules, BLM and USFS vegetation management

 

Though wildfires in California caused by power lines have prompted calls for more underground lines, Tucson Electric Power Co. plans to keep to its policy of burying lines selectively for safety.

Like many other utilities, TEP typically doesn’t install its long-range, high-voltage transmission lines, such as the TransWest Express project, and distribution equipment underground because of higher costs that would be passed on to ratepayers, TEP spokesman Joe Barrios said.

But the company will sometimes bury lower-voltage lines and equipment where it is cost-effective or needed for safety as utilities adapt to climate change across North America, or if customers or developers are willing to pay the higher installation costs

Underground installations generally include additional engineering expenses, right-of-way acquisition for projects like the New England Clean Power Link in other regions, and added labor and materials, Barrios said.

“This practice avoids passing along unnecessary costs to customers through their rates, so that all customers are not asked to subsidize a discretionary expenditure that primarily benefits residents or property owners in one small area of our service territory,” he said, adding that the Arizona Corporation Commission has supported the company’s policy.

Even so, TEP will place equipment underground in some circumstances if engineering or safety concerns, including electrical safety tips that utilities promote during storm season, justify the additional cost of underground installation, Barrios said.

In fact, lower-voltage “feeder” lines emerging from distribution substations are typically installed underground until the lines reach a point where they can be safely brought above ground, he added.

While in California PG&E has shut off power during windy weather to avoid wildfires in forested areas traversed by its power lines after events like the Drum Fire last June, TEP doesn’t face the same kind of wildfire risk, Barrios said.

Most of TEP’s 5,000 miles of transmission and distribution lines aren’t located in heavily forested areas that would raise fire concerns, though large urban systems have seen outages after station fires in Los Angeles, he said.

However, TEP has an active program of monitoring transmission lines and trimming vegetation to maintain a fire-safety buffer zone and address risks from vandalism such as copper theft where applicable, in compliance with federal regulations and in cooperation with the U.S. Bureau of Land Management and the U.S. Forest Service.

 

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$453M Manitoba Hydro line to Minnesota could face delay after energy board recommendation

Manitoba-Minnesota Transmission Project faces NEB certificate review, with public hearings, Indigenous consultation, and cross-border approval weighing permit vs certificate timelines, potential land expropriation, and Hydro's 2020 in-service date for the 308-MW intertie.

 

Key Points

A cross-border hydro line linking Manitoba and Minnesota, now under NEB review through a permit or certificate process.

✅ NEB recommends certificate with public hearings and cabinet approval

✅ Stakeholders cite land, health, and economic impacts along route

✅ Hydro targets May-June 2020 in-service despite review

 

A recommendation from the National Energy Board could push back the construction start date of a $453-million hydroelectric transmission line from Manitoba to Minnesota.

In a letter to federal Natural Resources Minister Jim Carr, the regulatory agency recommends using a "certificate" approval process, which could take more time than the simpler "permit" process Manitoba Hydro favours.

The certificate process involves public hearings, reflecting First Nations intervention seen in other power-line debates, to weigh the merits of the project, which would then go to the federal cabinet for approval.

The NEB says this process would allow for more procedural flexibility and "address Aboriginal concerns that may arise in the circumstances of this process."

The Manitoba-Minnesota Transmission Project would provide the final link in a chain that brings hydroelectricity from generating stations in northern Manitoba, through the Bipole III transmission line and, like the New England Clean Power Link project, across the U.S. border as part of a 308-megawatt deal with the Green Bay-based Wisconsin Public Service.

When Hydro filed its application in December 2016, it had expected to have approval by the end of August 2017 and to begin construction on the line in mid-December, in order to have the line in operation by May or June 2020.  

Groups representing stakeholders along the proposed route of the transmission line had mixed reactions to the energy board's recommendation.

A lawyer representing a coalition of more than 120 landowners in the Rural Municipality of Taché and around La Broquerie, Man., welcomed the opportunity to have a more "fulsome" discussion about the project.

"I think it's a positive step. As people become more familiar with the project, the deficiencies with it become more obvious," said Kevin Toyne, who represents the Southeast Stakeholders Coalition.

Toyne said some coalition members are worried that Hydro will forcibly expropriate land in order to build the line, while others are worried about potential economic and health impacts of having the line so close to their homes. They have proposed moving the line farther east.

When the Clean Environment Commission — an arm's-length provincial government agency — held public hearings on the proposed route earlier this year, the coalition brought their concerns forward, echoing Site C opposition voiced by northerners, but Toyne says both the commission and Hydro ignored them.

Hydro still aiming for 2020 in-service date

The Manitoba Métis Federation also participated in those public hearings. MMF president David Chartrand worries about the impact a possible delay, as seen with the Site C work halt tied to treaty rights, could have on revenue from sales of hydroelectric power to the U.S.

"I know that a lot of money, billions have been invested on this line. And if the connection line is not done, then of course this will be sitting here, not gaining any revenue, which will affect every Métis in this province, given our Hydro bill's going to go up," Chartrand said.The NEB letter to Minister Carr requests that he "determine this matter in an expedited manner."

Manitoba Hydro spokesperson Bruce Owen said in an email that the Crown corporation will participate in whatever process, permit or certificate, the NEB takes.

"Manitoba Hydro does not have any information at this point in time that would change the estimated in-service date (May-June 2020) for the Manitoba-Minnesota Transmission Project," he said.

The federal government "is currently reviewing the NEB's recommendation to designate the project as subject to a certificate, which would result in public hearings," said Alexandre Deslongchamps, a spokesperson for Carr.

"Under the National Energy Board Act, an international power line requires either the approval by the NEB through a permit or approval by the Government of Canada by a certificate. Both must be issued by the NEB," he wrote in an email to CBC News.

By law, the certificate process is not to take longer than 15 months.

 

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BC Ferries celebrates addition of hybrid ships

BC Ferries Island Class hybrid ferries deliver quiet, battery-electric travel with shore power readiness, lower emissions, and larger capacity on northern routes, protecting marine wildlife while replacing older vessels on Powell River and Texada services.

 

Key Points

Hybrid-electric ferries using batteries and diesel for quiet, low-emission service, ready for shore power upgrades.

✅ Operate 20% electric at launch; future full-electric via shore power

✅ 300 passengers, 47 vehicles; replacing older, smaller vessels

✅ Quieter transits help protect West Coast whales and marine habitat

 

In a champagne celebration, BC Ferries welcomed two new, hybrid-electric ships into its fleet Wednesday. The ships arrived in Victoria last month, and are expected to be in service on northern routes by the summer.

The Island Aurora and Island Discovery have the ability to run on either diesel or electricity.

"The pressure on whales on the West Coast is very intense right now," said BC Ferries CEO Mark Collins. "Quiet operation is very important. These ships will be gliding out of the harbor quietly and electrically with no engines running, that will be really great for marine space."

BC Ferries says the ships will be running on electricity 20 per cent of the time when they enter service, but the company hopes they can run on electricity full-time in the future. That would require the installation of shoreline power, which the company hopes to have in place in the next five to 10 years. Each ship costs around $40-million, a price tag that the federal government partially subsidized through CIB support as part of the electrification push.

When the two ships begin running on the Powell River to Texada, and Port McNeill, Alert Bay, and Sointula routes, two older vessels will be retired.

On Kootenay Lake, an electric-ready ferry is slated to begin operations in 2023, reflecting the province's wider shift.

"They are replacing a 47-car ferry, but on some routes they will be replacing a 25-car ferry, so those routes will see a considerable increase in service," said Collins.

Although the ships will not be servicing Colwood, the municipality's mayor is hoping that one day, they will.

"We can look at an electric ferry when we look at a West Shore ferry that would move Colwood residents to Victoria," said Mayor Rob Martin, noting that across the province electric school buses are hitting the road as well. "Here is a great example of what BC Ferries can do for us."

BC Ferries says it will be adding four more hybrid ships to its fleet by 2022, and is working on adding hybrid ships that could run from Victoria to Tsawwassen, similar to Washington State Ferries' hybrid upgrade underway in the region. 

B.C’s first hybrid-electric ferries arrived in Victoria on Saturday morning ushering in a new era of travel for BC Ferries passengers, as electric seaplane flights are also on the horizon for the region.

“It’s a really exciting day for us,” said Tessa Humphries, spokesperson for BC Ferries.

It took the ferries 60 days to arrive at the Breakwater District at Ogden Point. They came all the way from Constanta, Romania.

“These are battery-equipped ships that are designed for fully electric operation; they are outfitted with hybrid technology that bridges the gap until the EV charging infrastructure and funding is available in British Columbia,” said Humphries.

The two new "Island Class" vessels arrived at about 9 a.m. to a handful of people eagerly wanting to witness history.

Sometime in the next few days, the transport ship that brought the new ferries to B.C. will go out into the harbor and partially submerge to allow them to be offloaded, Humphries said.

The transfer process could happen in four to five days from now. After the final preparations are finished at the Breakwater District, the ships will be re-commissioned in Point Hope Maritime and then BC Ferries will officially take ownership.

“We know a lot of people are interested in this so we will put out advisory once we have more information as to a viewing area to see the whole process,” said Humphries.

Both Island Class ferries can carry 300 passengers and 47 vehicles. They won’t be sailing until later this year, but Humphries tells CTV News they will be named by the end of February. 

 

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California Legislators Prepare Vote to Crack Down on Utility Spending

California Utility Spending Bill scrutinizes how ratepayer funds are used by utilities, targeting lobbying, advertising, wildfire prevention cost pass-throughs, and CPUC oversight to curb high electricity bills and increase accountability and transparency statewide.

 

Key Points

Legislation restricting utilities from using ratepayer money for lobbying and ads, with stronger CPUC oversight.

✅ Bans ratepayer-funded lobbying and political advertising

✅ Expands prohibited utility communications and influence spending

✅ Aims to curb bills, boost transparency, and CPUC accountability

 

California's legislators are about to vote on a bill that would impose stricter regulations on how utility companies spend the money they collect from ratepayers. This legislation directly responds to the growing discontent among Californians who are already grappling with high electricity bills, as Californians ask why electricity prices are soaring amid wildfire prevention efforts.

Consumer rights groups have been vehemently critical of how utilities have been allocating customer funds, amid growing calls for regulatory action from state officials. They allege that a substantial portion of this money is being funnelled into lobbying efforts and advertising campaigns that yield no direct benefits for the customers themselves.

The proposed bill would significantly broaden the definition of what constitutes prohibited advertising and political influence activities on the part of utility companies, separate from income-based fixed electricity charges proposals that affect rate design. This would effectively restrict the ways in which utilities can utilize customer funds for such purposes.

While consumer advocacy groups have favored the legislation, it has drawn opposition from utility companies and some labor unions, as lawmakers weigh overturning income-based utility charges in parallel debates. Opponents contend that it would hinder utilities' ability to communicate effectively with their customers and advocate for their interests. Additionally, they express concerns that the bill could result in job losses within the utility sector.

The vote on the bill is expected to take place on Monday. The outcome of the vote is uncertain, but it is sure to be a closely watched development for Californians struggling with the burden of high electricity bills, with many wondering about major changes to their electric bills in the near term.

 

California's Electricity Rates: A Burden for Residents

A recent report by the California Public Utilities Commission (CPUC) revealed that the average Californian household spends a significantly higher amount on electricity compared to the national average. This disparity in electricity rates can be attributed to a number of factors, including the financial costs associated with wildfire prevention measures, investments in renewable energy infrastructure, and maintenance of aging electrical grids, even as the state considers revamping electricity rates to clean the grid.

 

Examples of Utility Company Spending that Raise Concerns

Consumer rights groups have specifically highlighted instances where utility companies have used customer money to fund lavish executive compensation packages, sponsor professional sports teams, and finance political campaigns. They argue that these expenditures do not provide any tangible benefits to ratepayers and should not be funded through customer bills.

 

The Need for Accountability and Prioritization

Proponents of the bill believe that the legislation is necessary to ensure that utility companies are held accountable for how they spend customer funds. They believe that the stricter regulations would compel utilities to prioritize investments that directly improve the quality and reliability of electricity services for Californians, alongside discussions of income-based flat-fee utility bills that could reshape rate structures.

The impending vote on the bill underscores the ongoing tension between the need for reliable electricity services and the desire to keep utility rates affordable for Californians. The outcome of the vote is likely to have a significant impact on how utility companies operate in the state and how much Californians pay for their electricity.

 

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