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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Mines found at Ukraine's Zaporizhzhia nuclear plant, UN watchdog says

Zaporizhzhia Nuclear Plant Mines reported by IAEA at the Russian-occupied site: anti-personnel devices in a buffer zone, restricted areas; access limits to reactor rooftops and turbine halls heighten nuclear safety and security concerns in Ukraine.

 

Key Points

IAEA reports anti-personnel mines at Russian-held Zaporizhzhia, raising nuclear safety risks in buffer zones.

✅ IAEA observes mines in buffer zone at occupied site

✅ Restricted areas; no roof or turbine hall access granted

✅ Safety systems unaffected, but staff under pressure

 

The United Nations atomic watchdog said it saw anti-personnel mines at the site of Ukraine's Zaporizhzhia nuclear power plant which is occupied by Russian forces.

Europe's largest nuclear facility fell to Russian forces shortly after the invasion of Ukraine in February last year, as Moscow later sought to build power lines to reactivate it amid ongoing control of the area. Kyiv and Moscow have since accused each other of planning an incident at the site.

On July 23 International Atomic Energy Agency (IAEA) experts "saw some mines located in a buffer zone between the site's internal and external perimeter barriers," agency chief Rafael Grossi said in a statement on Monday.

The statement did not say how many mines the team had seen.

The devices were in "restricted areas" that operating plant personnel cannot access, Mr Grossi said, adding the IAEA's initial assessment was that any detonation "should not affect the site's nuclear safety and security systems".

Laying explosives at the site was "inconsistent with the IAEA safety standards and nuclear security guidance" and, amid controversial proposals on Ukraine's nuclear plants that have circulated internationally, created additional psychological pressure on staff, he added.

Ukrainians in Nikopol are out of water and within Russia's firing line. But Zaporizhzhia nuclear power plant could pose the biggest threat, even as Ukraine has resumed electricity exports to regional grids.

Last week the IAEA said its experts had carried out inspections at the plant, without "observing" the presence of any mines, although they had not been given access to the rooftops of the reactor buildings, while a possible agreement to curb attacks on plants was being discussed.

The IAEA had still not been given access to the roofs of the reactor buildings and their turbine halls, its latest statement said, even as a proposal to control Ukraine's nuclear plants drew scrutiny.

After falling into Russian hands, Europe's biggest power plant was targeted by gunfire and has been severed from the grid several times, raising nuclear risk warnings from the IAEA and others.

The six reactor units, which before the war produced around a fifth of Ukraine's electricity, have been shut down for months, prompting interest in wind power development as a harder-to-disrupt source.

 

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Iran Says Deals to Rehabilitate, Develop Iraq Power Grid Finalized

Iran-Iraq Power Grid Deals reinforce electricity and natural gas ties, upgrading transmission in Karbala and Najaf, repairing transformers, easing sanctions bottlenecks, and weighing GCC interconnection to diversify supply and reduce distribution losses across Iraq.

 

Key Points

Agreements to rehabilitate Iraq's grid, cut losses, and secure power via Iranian gas, electricity, and upgrades.

✅ Reduce distribution losses in Karbala and Najaf

✅ Repair and replace damaged distribution transformers

✅ Coordinate payments to TAVANIR amid US sanctions

 

Iran and Iraq have finalized two deals to rehabilitate and develop the power grid of Iraq, while Iran is upgrading thermal plants to combined cycle at home to save energy, IRNA cited the Iranian Energy Minister Reza Ardakanian.

Ardakanian met his Iraqi counterpart Majid Mahdi Hantoush in Tehran on Tuesday evening for talks on further energy cooperation on the sidelines of Prime Minister Mustafa al-Kadhimi’s trip to the Islamic Republic on his first foreign visit.

“It was decided that the contracts related to reducing losses on the electricity distribution network in the provinces of Karbala and Najaf, as well as the contract for repairing Iraq’s distribution transformers would be finalized and signed,” the Iranian minister said.

Iraq relies on Iran for natural gas that generates as much as 45 percent of its electricity, with Iran supplying 40% of Iraq’s power according to sector reports. Iran transmits another 1,200 MW directly, and has regional power hub plans as well, making itself an indispensable energy source for its Arab neighbor, but the United States is trying to pry Baghdad away from Tehran’s orbit.

The US has been enlisting its companies and allies such as Saudi Arabia to replace Iran as Iraq’s source of energy.

Iran’s money from exports of gas and electricity has accumulated in bank accounts in Iraq, because US sanctions are preventing Tehran from repatriating it.

In January, an official said the sanctions were giving Iran a run for five billion dollars, “sedimenting” at the Central Bank of Iraq, because Tehran could not access it.

Ardakanian said the issue was brought up in the discussions on Tuesday and it was agreed that “the payment of part of TAVANIR (Iran Power Generation and Transmission Company)’s claims will start from the end of July”.

The US administration is pushing for a deal between Washington, Baghdad and six Persian Gulf states to connect Iraq’s nationwide power grid to that of the Persian Gulf Cooperation Council, while Uzbekistan looks to export power to Afghanistan as regional linkages expand.

The US State Department said in a statement last Thursday that the six countries that make up the (Persian) Gulf Cooperation Council Interconnection Authority (GCCIA) — Saudi Arabia, Kuwait, Bahrain, Qatar, Oman and the UAE — had affirmed their shared support for the project to supply electricity to Iraq.

Iraq needs more than 23,000 MW of electricity to meet its domestic demand, and is exploring nuclear power plans to tackle shortages, but years of war following the 2003 US invasion have left its power infrastructure in tatters and a deficit of some 7,000 MW.

In the past, officials in Baghdad have said there is no easy substitute to imports from Iran because it will take years to adequately build up Iraq’s energy infrastructure, and meeting summer electricity needs remains a persistent challenge.

They have said American demand acknowledges neither Iraq’s energy needs nor the complex relations between Baghdad and Tehran.

In addition to natural gas and electricity, Iraq imports a wide range of goods from Iran including food, agricultural products, home appliances, and air conditioners.

On Tuesday, the Iraqi prime minister said during a joint news conference with Iranian President Hassan Rouhani that the purpose of his trip to Tehran was to strengthen historical ties between the two countries, especially in light of the challenges they faced as a result of the coronavirus outbreak and the fall of oil prices.

“In the face of such challenges, we need coordination between the two countries in a way that serves the interests of Iran and Iraq.”

Both Iran and Iraq, Kadhimi said, suffer from economic problems, adding the two countries need comprehensive and inclusive cooperation to overcome them.

Kadhimi said Iran-Iraq relations are not merely due to the geographical location of the two countries and their 1,450-km border, adding the ties are based on religion and culture and rooted in history.

“I am reiterating to my brothers in the Islamic Republic of Iran that the Iraqi nation is eager to have excellent relations with the Islamic Republic of Iran based on the principle of non-interference in the internal affairs of the two countries.”

Kadhimi said Iran and Iraq fought against terrorism and Takfiri groups together, and the Islamic Republic of Iran was one of the first countries to stand by Iraq.

“We will not forget this. That is why Iraq has stood with Iran to help it overcome economic challenges and turned to a big market for trade with Iran,” he said.

“We seek stability in Iraq and our philosophy and view of Iran is that we consider Iran a stable, strong, prosperous and progressive country, and this fact is in the interest of Iraq and the territorial integrity of the region,” he added.

According to Kadhimi, the two sides discussed implementing agreements between them, including connecting their railway through Khorramshahr in Iran and Basra in Iraq, adding he was very confident the agreements would be implemented soon.

Iraq’s delegation included the ministers of foreign affairs, finance, health, and planning, as well as Kadhimi’s national security adviser, some of whom also met their Iranian counterparts.

Last year, Iran’s exports to Iraq amounted to nearly $9 billion, IRNA reported. It said the two nations will discuss increasing that amount to $20 billion.

“The two governments’ will is to expand bilateral trade to $20 billion,” Rouhani said after an hour-long meeting with the Iraqi prime minister.

 

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Sierra Club: Governor Abbott's Demands Would Leave Texas More Polluted and Texans in the Dark

Texas Energy Policy Debate centers on ERCOT and PUC directives, fossil fuels vs renewables, grid reliability, energy efficiency, battery storage, and blackout risks, shaping Texas power market rules, conservation alerts, and capacity planning.

 

Key Points

Policy fight over ERCOT/PUC rules weighing fossil fuels vs renewables and storage to bolster Texas grid reliability.

✅ ERCOT and PUC directives under political scrutiny

✅ Fossil fuel subsidies vs renewable incentives and storage

✅ Focus on grid reliability, efficiency, and blackout prevention

 

Earlier this week, Governor Abbott released a letter to the Public Utility Commission of Texas (PUC) and the Electric Reliability Council of Texas (ERCOT), demanding electricity market reforms that Abbott falsely claims will "increase power generation capacity and to ensure the reliability of the Texas power grid."

Unfortunately, Abbott's letter promotes polluting, unreliable fossil fuels, attacks safer clean energy options, and ignores solutions that would actually benefit everyday Texans.

"Governor Abbott, in a blatant effort to politicize Texans' energy security, wants to double down on fossil fuels, even though they were the single largest point of failure during both February's blackouts and June's energy conservation alerts," said Cyrus Reed, Interim Director & Conservation Director of the Lone Star Chapter of the Sierra Club.

"Many of these so-called solutions were considered and rejected most recently by the Texas Legislature. Texas must focus on expanding clean and reliable renewable energy, energy efficiency, and storage capacity, as voters consider funding to modernize generation in the months ahead.

"We can little afford to repeat the same mistakes that have failed to provide enough electricity where it is needed most and cost Texans billions of dollars. Instead of advocating for evidence-based solutions, Abbott wants to be a culture warrior for coal and gas, even as he touts grid readiness amid election season, even when it results in blackouts across Texas."

 

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PG&E restoring power after intentional shut-offs affect 20,500 customers

PG&E power restoration continues across Butte and Yuba counties after PSPS shut-offs from high winds and dry weather, with crews patrolling overhead lines, repairing damage, and reopening community resource centers near Lake Berryessa.

 

Key Points

PG&E power restoration safely re-energizes lines after PSPS, using inspections and repairs to restore service.

✅ Crews patrolled 800 miles of overhead lines for hazards

✅ Repairs followed wind damage; gradual re-energization

✅ Resource centers offered water, outlets, air conditioning

 

Pacific Gas and Electric Co. field crews have begun restoring power to approximately 20,500 customers in Butte and Yuba counties after the utility shut off electricity to reduce wildfire risk because of gusty winds and dry weather conditions.

More than half of the affected customers had electricity again as of 1:47 p.m. Sunday, according to PG&E, and by 4 p.m. all of Yuba County power had been restored.

The utility also cut electricity for about 1,600 customers in parts of Napa, Solano and Yolo counties, primarily in the Lake Berryessa area, in a PSPS event separate from statewide grid conservation alerts that can trigger rolling blackouts. Power to those areas was switched off at 6:15 a.m. Saturday but was restored by the evening.

As the danger subsided Sunday, utility workers, as part of PG&E's local response planning for winter storms, worked throughout Butte and Yuba counties to re-energize power lines. The shut-offs affected areas including eastern Chico, Oroville and fire-ravaged Paradise.

Technicians checked lines for damage or fire hazards, like vegetation that could interfere with live wires, Pasion said, as part of broader pandemic grid preparedness that informed utility protocols.

PG&E “patrolled approximately 800 miles of overhead power lines,” the company said in a statement. “Crews found instances of damage to de-energized equipment caused by the extreme weather event and are making necessary repairs.”

While the shut-offs inconvenienced businesses and homeowners, they also highlighted energy inequality across impacted neighborhoods, and some called 911 with emergencies and confusion.

A half hour into the shut-off Saturday night, Butte County sheriff’s dispatchers received a call from a person requesting a welfare check on an individual whose care required electricity, according to department call logs. Two calls overnight from the Magalia area requested medical assistance because residents had oxygen concerns for medically sensitive spouses.

One woman requested an ambulance because her “husband was running out of oxygen,” according to the logs.

Around 4:11 a.m. Sunday, a resident of Hidden Valley Mobile Home Park in Oroville called about a tree falling into a trailer, causing a power line to fall, but noted that the electricity was off.

In a comparable storm-related outage, Sudbury Hydro crews worked to reconnect service after severe weather in Ontario.

And there were multiple calls asking for information about the shut-off, including one caller around midnight who was “demanding PG&E turn his power back on.”

The calls led the Butte County Sheriff’s Office to tweet a reminder Sunday afternoon that 911 is reserved for emergencies and requests for information about the power shutdown should be done through PG&E.

The utility opened a community resource center at Harrison Stadium in Oroville (Butte County) on Sunday morning to provide restrooms, bottled water, power outlets and air conditioning to residents. About 40 people showed up at the center in the first few hours, officials said.

“It’s a small but steady stream,” Pasion said.

Power was being restored to parts of Oroville as of 11 a.m. Sunday.

PG&E officials said it could take up to 48 hours for power to be restored in some areas.

For perspective, during severe storms in Ontario, Hydro One crews restored power to more than 277,000 customers within days.

 

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Duke solar solicitation nearly 6x over-subscribed

Duke Energy Carolinas Solar RFP draws 3.9 GW of utility-scale bids, oversubscribed in DEP and DEC, below avoided cost rates, minimal battery storage, strict PPA terms, and interconnection challenges across North and South Carolina.

 

Key Points

Utility-scale solar procurement in DEC and DEP, evaluated against avoided cost, with few storage bids and PPA terms.

✅ 3.9 GW bids for 680 MW; DEP most oversubscribed

✅ Most projects 7-80 MWac; few include battery storage

✅ Bids must price below 20-year avoided cost estimate

 

Last week the independent administrator for Duke’s 680 MW solar solicitation revealed data about the projects which have bid in response to the offer, showing a massive amount of interest in the opportunity.

Overall, 18 individuals submitted bids for projects in Duke Energy Carolinas (DEC) territory and 10 in Duke Energy Progress (DEP), with a total of more than 3.9 GW of proposals – more nearly 6x the available volume. DEP was relatively more over-subscribed, with 1.2 GWac of projects vying for only 80 MW of available capacity.

This is despite a requirement that such projects come in below the estimate of Duke’s avoided cost for the next 20 years, and amid changes in solar compensation that could affect project economics. Individual projects varied in capacity from 7-80 MWac, with most coming within the upper portion of that range.

These bids will be evaluated in the spring of 2019, and as Duke Energy Renewables continues to expand its portfolio, Duke Energy Communications Manager Randy Wheeless says he expects the plants to come online in a year or two.

 

Lack of storage

Despite recent trends in affordable batteries, of the 78 bids that came in only four included integrated battery storage. Tyler Norris, Cypress Creek Renewables’ market lead for North Carolina, says that this reflects that the methodology used is not properly valuing storage.

“The lack of storage in these bids is a missed opportunity for the state, and it reflects a poorly designed avoided cost rate structure that improperly values storage resources, commercially unreasonable PPA provisions, and unfavorable interconnection treatment toward independent storage,” Norris told pv magazine.

“We’re hopeful that these issues will be addressed in the second RFP tranche and in the current regulatory proceedings on avoided cost and state interconnection standards and grid upgrades across the region.”

 

Limited volume for North Carolina?

Another curious feature of the bids is that nearly the same volume of solar has been proposed for South Carolina as North Carolina – despite this solicitation being in response to a North Carolina law and ongoing legal disputes such as a church solar case that challenged the state’s monopoly model.

 

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Electric Cooperatives, The Lone Shining Utility Star Of The Texas 2021 Winter Storm

Texas Electric Cooperatives outperformed during Winter Storm Uri, with higher customer satisfaction, equitable rolling blackouts, and stronger grid reliability compared to deregulated markets, according to ERCOT-area survey data of regulated utilities and commercial providers.

 

Key Points

Member-owned utilities in Texas delivering power, noted for reliability and fair outages during Winter Storm Uri.

✅ Member-owned, regulated utilities serving local communities

✅ Rated higher for blackout management and communication

✅ Operate outside deregulated markets; align incentives with users

 

Winter Storm Uri began to hit parts of Texas on February 13, 2021 and its onslaught left close to 4.5 million Texas homes and businesses without power, and many faced power and water disruptions at its peak. By some accounts, the preliminary number of deaths attributed to the storm is nearly 200, and the economic toll for the Lone Star State is estimated to be as high as $295 billion. 

The more than two-thirds of Texans who lost power during this devastating storm were notably more negative than positive in their evaluation of the performance of their local electric utility, mirrored by a rise in electricity complaints statewide, with one exception. That exception are the members of the more than 60 electric cooperatives operating within the Texas Interconnection electrical grid, which, in sharp contrast to the customers of the commercial utilities that provide power to the majority of Texans, gave their local utility a positive evaluation related to its performance during the storm.

In order to study Winter Storm Uri’s impact on Texas, the Hobby School of Public Affairs at the University of Houston conducted an online survey during the first half of March of residents 18 and older who live in the 213 counties (91.5% of the state population) served by the Texas power grid, which is managed by the Electric Reliability Council of Texas (ERCOT). 

Three-quarters of the survey population (75%) live in areas with a deregulated utility market, where a specified transmission and delivery utility by region is responsible for delivering the electricity (purchased from one of a myriad of private companies by the consumer) to homes and businesses. The four main utility providers are Oncor, CenterPoint CNP -2.2%, American Electric Power (AEP) North, and American Electric Power (AEP) Central. 

The other 25% of the survey population live in areas with regulated markets, where a single company is responsible for both delivering the electricity to homes and businesses and serves as the only source from which electricity is purchased. Municipal-owned and operated utilities (e.g., Austin Energy, Bryan Texas Utilities, Burnet Electric Department, Denton Municipal Electric, New Braunfels Utilities, San Antonio’s CPS Energy CMS -2.1%) serve 73% of the regulated market. Electric cooperatives (e.g., Bluebonnet Electric Cooperative, Central Texas Electric Cooperative, Guadalupe Valley Cooperative, Lamb County Electric Cooperative, Pedernales Electricity Cooperative, Wood County Electric Cooperative) serve one-fifth of this market (21%), with private companies accounting for 6% of the regulated market.

The overall distribution of the survey population by electric utility providers is: Oncor (38%), CenterPoint (21%), municipal-owned utilities (18%), AEP Central & AEP North combined (12%), electric cooperatives (6%), other providers in the deregulated market (4%) and other providers in the regulated market (1%). 

There were no noteworthy differences among the 31% of Texans who did not lose power during the winter storm in regard to their evaluations of their local electricity provider or their belief that the power cuts in their locale were carried out in an equitable manner.  

However, among the 69% of Texans who lost power, those served by electric cooperatives in the regulated market and those served by private electric utilities in the deregulated market differed notably regarding their evaluation of the performance of their local electric utility, both in regard to their management of the rolling blackouts, amid debates over market reforms to avoid blackouts, and to their overall performance during the winter storm. Those Texans who lost power and are served by electric cooperatives in a regulated market had a significantly more positive evaluation of the performance of their local electric utility than did those Texans who lost power and are served by a private company in a deregulated electricity market. 

For example, only 24% of Texans served by electric cooperatives had a negative evaluation of their local electric utility’s overall performance during the winter storm, compared to 55%, 56% and 61% of those served by AEP, Oncor and CenterPoint respectively. A slightly smaller proportion of Texans served by electric cooperatives (22%) had a negative evaluation of their local electric utility’s performance managing the rolling blackouts during the winter storm, compared to 58%, 61% and 71% of Texans served by Oncor, AEP and CenterPoint, respectively.

Texans served by electric cooperatives in regulated markets were more likely to agree that the power cuts in their local area were carried out in an equitable manner compared to Texans served by commercial electricity utilities in deregulated markets. More than half (52%) of those served by an electric cooperative agreed that power cuts during the winter storm in their area were carried out in an equitable manner, compared to only 26%, 23% and 23% of those served by Oncor, AEP and CenterPoint respectively

The survey data did not allow us to provide a conclusive explanation as to why the performance during the winter storm by electric cooperatives (and to a much lesser extent municipal utilities) in the regulated markets was viewed more favorably by their customers than was the performance of the private companies in the deregulated markets viewed by their customers. Yet here are three, far from exhaustive, possible explanations.

First, electric cooperatives might have performed better (based on objective empirical metrics) during the winter storm, perhaps because they are more committed to their customers, who are effectively their bosses. .  

Second, members of electric cooperatives may believe their electric utility prioritizes their interests more than do customers of commercial electric utilities and therefore, even if equal empirical performance were the case, are more likely to rate their electric utility in a positive manner than are customers of commercial utilities.  

Third, regulated electric utilities where a single entity is responsible for the commercialization, transmission and distribution of electricity might be better able to respond to the type of challenges presented by the February 2021 winter storm than are deregulated electric utilities where one entity is responsible for commercialization and another is responsible for transmission and distribution, aligning with calls to improve electricity reliability across Texas.

Other explanations for these findings may exist, which in addition to the three posited above, await future empirical verification via new and more comprehensive studies designed specifically to study electric cooperatives, large commercial utilities, and the incentives that these entities face under the regulatory system governing production, commercialization and distribution of electricity, including rulings that some plants are exempt from providing electricity in emergencies under state law. 

Still, opinion about electricity providers during Winter Storm Uri is clear: Texans served by regulated electricity markets, especially by electric cooperatives, were much more satisfied with their providers’ performance than were those in deregulated markets. Throughout its history, Texas has staunchly supported the free market. Could Winter Storm Uri change this propensity, or will attempts to regulate electricity lessen as the memories of the storm’s havoc fades? With a hotter summer predicted to be on the horizon in 2021 and growing awareness of severe heat blackout risks, we may soon get an answer.   

 

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