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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Rio Tinto seeking solutions that transform heat from underground mines into electricity

Rio Tinto waste heat-to-electricity initiative captures underground mining thermal energy at Resolution Copper, Arizona, converting it to renewable power for cooling systems and microgrids, advancing decarbonization, energy efficiency, and the miner's 2050 carbon-neutral goal.

 

Key Points

A program converting underground thermal energy into on-site electricity to cut emissions and support mine cooling.

✅ Captures low-grade heat from rock and geothermal water.

✅ Generates electricity for ventilation, refrigeration, microgrids.

✅ Scalable, safe, and grid- or storage-ready for peak demand.

 

The world’s second-largest miner, Rio Tinto announced that it is accepting proposals for solutions that transform waste heat into electricity for reuse from its underground operations.

In a press release, the company said this initiative is aimed at drastically reducing greenhouse gas emissions, even as energy-intensive projects like bitcoin mining operations expand, so that it can achieve its goal of becoming carbon neutral by 2050.

Initially, the project would be implemented at the Resolution copper mine in Arizona, which Rio owns together with BHP (ASX, LON: BHP). At this site, massive electrically-driven refrigeration and ventilation systems, aligned with broader electrified mining practices, are in charge of cooling the work environment because of the latent heat from the underground rock and groundwater. 

THE INITIATIVE IS AIMED AT REDUCING GREENHOUSE GAS EMISSIONS SO THAT RIO CAN ACHIEVE ITS GOAL OF BECOMING CARBON NEUTRAL BY 2050

“When operating, the Resolution copper mine will be a deep underground block cave mine some 7,000 feet (~2 kilometres) deep, with ambient air temperatures ranging between 168°F to 180°F (76°C to 82°C), conditions that, during heat waves, when bitcoin mining power demand can strain local grids, further heighten cooling needs, and underground water at approximately 194°F (90°C),” the media brief states.

“Rio Tinto is seeking solutions to capture and reuse the heat from underground, contributing towards powering the equipment needed to cool the operations. The solution to capture and convert this thermal energy into electrical energy, such as emerging thin-film thermoelectrics, should be safe, environmentally friendly and cost-effective.”

The miner also said that, besides capturing heat for reuse, the solution should generate electrical energy from low range temperatures below the virgin rock temperature and/or from the high thermal water coming from the underground rock, similar to using transformer waste heat for heating in the power sector. 

At the same time, the solution should be scalable and easily transported through the many miles of underground tunnels that will be built to ventilate, extract and move copper ore to the surface.

Rio requires proposals to offer the possibility of distributing the electrical energy generated back into the electrical grid from the mining operation or stored and used at a later stage when energy is required during peak use periods, especially as jurisdictions aim to use more electricity for heat in colder seasons. 

 

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Alberta gives $40M to help workers transition from coal power jobs

Alberta Coal Transition Support offers EI top-ups, 75% wage replacement, retraining, tuition vouchers, and on-site advice for workers leaving thermal coal mines and coal-fired power plants during the provincial phase-out.

 

Key Points

Alberta Coal Transition Support is a $40M program providing EI top-ups, retraining, and tuition vouchers to coal workers.

✅ 75% EI top-up; province requests federal alignment

✅ Tuition vouchers and retraining for displaced workers

✅ On-site transition services; about 2,000 workers affected

 

Alberta is putting aside $40 million to help workers losing their jobs as the province transitions away from thermal coal mines and coal-fired power plants, a shift connected to the future of work in the electricity sector over the next decade.

Labour Minister Christina Gray says the money will top up benefits to 75 per cent of a worker’s previous earnings during the time they collect employment insurance, amid regional shifts such as how COVID-19 reshaped Saskatchewan in recent months.

Alberta is asking the federal government to not claw back existing benefits as the province tops up those EI benefits, as utilities face pressures like Manitoba Hydro cost-cutting during the pandemic, while also extending EI benefits for retiring coal workers.

Gray says even if the federal government does not step up, the province will provide the funds to match that 75 per cent threshold, a contrast to problems such as Kentucky miners' cold checks seen elsewhere.

There will also be help for workers in the form of tuition vouchers, retraining programs like the Nova Scotia energy training program that connects youth to the sector, and on-site transitioning advice.

The province estimates there are 2,000 workers affected.

 

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Western Canada drought impacting hydropower production as reservoirs run low

Western Canada Hydropower Drought strains British Columbia and Manitoba as reservoirs hit historic lows, cutting hydroelectric output and prompting power imports, natural gas peaking, and grid resilience planning amid climate change risks this winter.

 

Key Points

Climate-driven reservoir lows cut hydro in B.C. and Manitoba, prompting imports and backup gas to maintain reliability.

✅ Reservoirs at multi-year lows cut hydro generation capacity

✅ BC Hydro and Manitoba Hydro import electricity for reliability

✅ Natural gas turbines used; climate change elevates drought risk

 

Severe drought conditions in Western Canada are compelling two hydroelectricity-dependent provinces, British Columbia and Manitoba, to import power from other regions. These provinces, known for their reliance on hydroelectric power, are facing reduced electricity production due to low water levels in reservoirs this autumn and winter as energy-intensive customers encounter temporary connection limits.

While there is no immediate threat of power outages in either province, experts indicate that climate change is leading to more frequent and severe droughts. This trend places increasing pressure on hydroelectric power producers in the future, spurring interest in upgrading existing dams as part of adaptation strategies.

In British Columbia, several regions are experiencing "extreme" drought conditions as classified by the federal government. BC Hydro spokesperson Kyle Donaldson referred to these conditions as "historic," and a first call for power highlights the strain, noting that the corporation's large reservoirs in the north and southeast are at their lowest levels in many years.

To mitigate this, BC Hydro has been conserving water by utilizing less affected reservoirs and importing additional power from Alberta and various western U.S. states. Donaldson confirmed that these measures would persist in the upcoming months.

Manitoba is also facing challenges with below-normal levels in reservoirs and rivers. Since October, Manitoba Hydro has occasionally relied on its natural gas turbines to supplement hydroelectric production as electrical demand could double over the next two decades, a measure usually reserved for peak winter demand.

Bruce Owen, a spokesperson for Manitoba Hydro, reassured that there is no imminent risk of a power shortage. The corporation can import electricity from other regions, similar to how it exports clean energy in high-water years.

However, the cost implications are significant. Manitoba Hydro anticipates a financial loss for the current fiscal year, with more red ink tied to emerging generation needs, the second in a decade, with the previous one in 2021. That year, drought conditions led to a significant reduction in the company's power production capabilities, resulting in a $248-million loss.

The 2021 drought also affected hydropower production in the United States. The U.S. Department of Energy reported a 16% reduction in overall generation, with notable decreases at major facilities like Nevada's Hoover Dam, where production dropped by 25%.

Drought has long been a major concern for hydroelectricity producers, and they plan their operations with this risk in mind. Manitoba's record drought in 1940-41, for example, is a benchmark for Manitoba Hydro's operational planning to ensure sufficient electricity supply even in extreme low-water conditions.

Climate change, however, is increasing the frequency of such rare events, highlighting the need for more robust backup systems such as new turbine investments to enhance reliability. Blake Shaffer, an associate professor of economics at the University of Calgary specializing in electricity markets, emphasized the importance of hydroelectric systems incorporating the worsening drought forecasts due to climate change into their energy production planning.

 

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Thermal power plants’ PLF up on rising demand, lower hydro generation

India Coal Power PLF rose as capacity utilisation improved on rising peak demand and hydropower shortfall; thermal plants lifted plant load factor, IPPs lagged, and generation beat program targets amid weak rainfall and slower snowmelt.

 

Key Points

Coal plant load factor in India rose in May on higher demand and weak hydropower, with generation beating targets.

✅ PLF rose to 65.3% as demand climbed

✅ Hydel generation fell 14% YoY on poor rainfall

✅ IPP PLF at 57.8%, below 60% debt comfort

 

Capacity utilisation levels of coal-based power plants improved in May because of a surge in electricity demand and lower generation from hydroelectric sources. The plant load factor (PLF) of thermal power plants went up to 65.3% in the month, 1.7 percentage points higher than the year-ago period.

While PLFs of central and state government-owned plants were 75.5% and 64.5%, respectively, the same for independent power producers (IPPs) stood at 57.8%, even as coal and electricity shortages eased across the market. Though PLFs of IPPs were higher than May 2017 levels, it failed to cross the 60% mark, which eases debt servicing capabilities of power generation assets.

Thermal power plants generated 96,580 million units (MU) in May, 4% more than the programme set for the month and 5.2% higher than last year, partly supported by higher imported coal volumes in the market. On the other hand, hydel plants produced 10,638 MU, 10% lower than the target, reflecting a 14% decline from last year.

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Peak demand of power on the last day of the month was 1,62,132 MW, 4.3% higher than the demand registered in the same day a year ago, underscoring India's position as the third-largest electricity producer globally.

According to sources, hydropower plants have been generating lesser than expected electricity due to inadequate rainfall and snow melting at a slower pace than previous years, even as the US reported a power generation jump year on year. Data for power generation from renewable sources have not been made available yet.

 

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U.S. power companies face supply-chain crisis this summer

U.S. Power Grid Supply Shortages strain reliability as heat waves, hurricanes, and drought drive peak demand; transformer scarcity, gas constraints, and renewable delays raise outage risks across ERCOT and MISO, prompting FERC warnings.

 

Key Points

They are equipment and fuel constraints that, amid extreme weather and peak demand, elevate outage risks.

✅ Transformer shortages delay storm recovery and repairs.

✅ Record gas burn, low hydro tighten generation capacity.

✅ ERCOT and MISO warn of rolling outages in heat waves.

 

U.S. power companies are facing supply crunches amid the U.S. energy crisis that may hamper their ability to keep the lights on as the nation heads into the heat of summer and the peak hurricane season.

Extreme weather events such as storms, wildfires and drought are becoming more common in the United States. Consumer power use is expected to hit all-time highs this summer, reflecting unprecedented electricity demand across the Eastern U.S., which could strain electric grids at a time when federal agencies are warning the weather could pose reliability issues.

Utilities are warning of supply constraints for equipment, which could hamper efforts to restore power during outages. They are also having a tougher time rebuilding natural gas stockpiles for next winter, after the Texas power system failure highlighted cold-weather vulnerabilities, as power generators burn record amounts of gas following the shutdown of dozens of coal plants in recent years and extreme drought cuts hydropower supplies in many Western states.

"Increasingly frequent cold snaps, heat waves, drought and major storms continue to challenge the ability of our nation’s electric infrastructure to deliver reliable affordable energy to consumers," Richard Glick, chairman of the U.S. Federal Energy Regulatory Commission (FERC), said earlier this month.

Federal agencies responsible for power reliability like FERC have warned that grids in the western half of the country could face reliability issues this summer as consumers crank up air conditioners to escape the heat, with nationwide blackout risks not limited to Texas. read more

Some utilities have already experienced problems due to the heat. Texas' grid operator, the Electric Reliability Council of Texas (ERCOT), was forced to urge customers to conserve energy as the Texas power grid faced another crisis after several plants shut unexpectedly during an early heat wave in mid-May. read more

In mid-June, Ohio-based American Electric Power Co (AEP.O) imposed rolling outages during a heat wave after a storm damaged transmission lines and knocked out power to over 200,000 homes and businesses.

The U.S. Midwest faces the most severe risk because demand is rising while nuclear and coal power supplies have declined. read more

The Midcontinent Independent System Operator (MISO), which operates the grid from Minnesota to Louisiana, warned that parts of its coverage area are at increased risk of temporary outages to preserve the integrity of the grid.

Supply-chain issues have already delayed the construction of renewable energy projects across the country, and the aging U.S. grid is threatening progress on renewables and EVs. Those renewable delays coupled with tight power in the Midwest prompted Wisconsin's WEC Energy Group Inc (WEC.N) and Indiana's NiSource Inc (NI.N) to delay planned coal plant shutdowns in recent months.

BRACING FOR SUPPLY SHORTAGES
Utility operators are conserving their inventory of parts and equipment as they plan to prevent summer power outages during severe storms. Over the last several months, that means operators have been getting creative.

"We’re doing a lot more splicing, putting cables together, instead of laying new cable because we're trying to maintain our new cable for inventory when we need it," Nick Akins, chief executive of AEP, said at the CERAWeek energy conference in March.

Transformers, which often sit on top of electrical poles and convert high-voltage energy to the power used in homes, are in short supply.

New Jersey-based Public Service Enterprise Group Inc (PSEG) (PEG.N) Chief Executive Ralph Izzo told Reuters the company has had to look at alternate supply options for low voltage transformers.

"You don’t want to deplete your inventory because you don't know when that storm is coming, but you know it's coming," Izzo said.

Some utilities are facing waiting times of more than a year for transformer parts, the National Rural Electric Cooperative Association and the American Public Power Association told U.S. Energy Secretary Jennifer Granholm in a May letter.

Summer is just starting, but U.S. weather so far this year has already been about 21% warmer than the 30-year norm, according to data provider Refinitiv.

"If we have successive days of 100-degree-heat, those pole top transformers, they start popping like Rice Krispies, and we would not have the supply stack to replace them," Izzo said.

 

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The Need for Electricity During the COVID-19 Pandemic

US utilities COVID-19 resilience shows electric utilities maintaining demand stability, reaffirming earnings guidance, and accessing the bond market for low-cost financing, as Dominion, NextEra, and Con Edison manage recession risks.

 

Key Points

It is the sector's capacity to sustain demand, financing access, and guidance despite pandemic recession pressures.

✅ Bond market access locks in low-cost, long-term debt

✅ Stable residential load offsets industrial weakness

✅ Guidance largely reaffirmed by major utilities

 

Dominion Energy (D) expects "incremental residential load" gains, consistent with COVID-19 electricity demand patterns, as a result of COVID-19 fallout. Southern Company CEO Tom Fanning says his company is "nowhere near" a need to review earnings guidance because of a potential recession, in a region where efficiency and demand response can help level electricity demand for years.

Sempra Energy (SRE) has reaffirmed earnings per share guidance for 2020 and 2021, as well timing for the sale of assets in Chile and Peru, and peers such as Duke Energy's renewables plan have reaffirmed capital investments to deliver cleaner energy and economic growth. And Xcel Energy (XEL) says it still "hasn’t seen material impact on its business."

Several electric utilities have demonstrated ability to tap the bond market, in line with utility sector trends in recent years, to lock in low-cost financing, as America moves toward broader electrification, despite ongoing turmoil. Their ranks include Dominion Energy, renewable energy leader NextEra Energy (NEE) and Consolidated Edison (ED), which last week sold $1 billion of 30-year bonds at a coupon rate of just 3.95 percent.

It’s still early days for US COVID-19 fallout. And most electric companies have yet to issue guidance. That’s understandable, since so much is still unknown about the virus and the damage it will ultimately do to human health and the global economy. But so far, the US power industry is showing typical resilience in tough times, as it coordinates closely with federal partners to maintain reliability.

Will it last? We won’t know for certain until there’s a lot more data. NextEra is usually first to report its Q1 earnings reports and detailed guidance. But that’s not expected until April 23. And companies may delay financials further, should the virus and efforts to control it impede collection and analysis of data, and as they address electricity shut-off risks affecting customers.

 

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