NEMA publishes standards for boxes, covers, and supports

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The National Electrical Manufacturers Association (NEMA) has published OS 1-2008 Sheet-Steel Outlet Boxes, Device Boxes, Covers, and Box Supports and OS 2-2008 Nonmetallic Outlet Boxes, Device Boxes, Covers, and Box Supports.

OS 1-2008 and OS 2-2008 describe standard configurations for outlet boxes 100 cubic inches or less, as well as manufacturer specifications for materials, corrosion protection, dimensions of openings, supports, cover screws, markings, and provisions for grounding. The standards specify dimensions necessary for compatibility with NEMA standard wiring devices and help manufacturers ensure that box constructions comply with the National Electrical Code as well as UL listing requirements.

“OS 1 and OS 2 are the essential industry standards for maintaining compatibility of metal and nonmetallic outlet boxes with standardized wiring devices and conduit and cable systems,” said Daniel Kissane, chairman of the Outlet & Switch Box Section. “These revisions serve to increase both standards’ utility to manufacturers and building specifiers.”

The standards were last revised in 2003. Two of the changes made to OS 1 include additional marking requirements for boxes for ceiling-suspended fan support and clarification to marking requirements for clamps furnished as part of a box. OS 2 includes updated definitions, revised requirements for fixture boxes, and a modified Table 2-2.

The contents and scope of OS 1 may be viewed, or a hardcopy or electronic copy purchased for $129, by visiting www.nema.org/stds/os1.cfm. The contents and scope of OS 2 may be viewed, or a hardcopy or electronic copy purchased for $82, by visiting www.nema.org/stds/os2.cfm. Standards may also be purchased by contacting IHS at 800-854-7179 (within the U.S.), 303-397-7956 (international), 303-397-2740 (fax), or global.ihs.com.

NEMA is the association of electrical and medical imaging equipment manufacturers. Founded in 1926 and headquartered near Washington, D.C., its approximately 450 member companies manufacture products used in the generation, transmission and distribution, control, and end use of electricity.

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Cape Town to Build Own Power Plants, Buy Additional Electricity

Cape Town Renewable Energy Plan targets 450+ MW via solar, wind, and battery storage, cutting Eskom reliance, lowering greenhouse gas emissions, stabilizing electricity prices, and boosting grid resilience through municipal procurement, PPAs, and city-owned plants.

 

Key Points

A municipal plan to procure over 450 MW, cut Eskom reliance, stabilize prices, and reduce Cape Town emissions.

✅ Up to 150 MW from private plants within the city

✅ 300 MW to be purchased from outside Cape Town later

✅ City financing 100-200 MW of its own generation

 

Cape Town is seeking to secure more than 450 megawatts of power from renewable sources to cut reliance on state power utility Eskom Holdings SOC Ltd., where wind procurement cuts were considered during lockdown, and reduce greenhouse gas emissions.

South Africa’s second-biggest city is looking at a range of options, including geothermal exploration in comparable markets, and expects the bulk of the electricity to be generated from solar plants, Kadri Nassiep, the city’s executive director of energy and climate change, said in an interview.

On July 14 the city of 4.6 million people released a request for information to seek funding to build its own plants. This month or next it will seek proposals for the provision of as much as 150 megawatts from privately owned plants, largely solar additions, to be built and operated within the city, he said. As much as 300 megawatts may also be purchased at a later stage from plants outside of Cape Town, according to Nassiep.

The city could secure finance to build 100 to 200 megawatts of its own generation capacity, Nassiep said. “We realized that it is important for the city to be more in control around the pricing of the power,” he added.

Power Outages

Cape Town’s foray into the securing of power from sources other than Eskom comes after more than a decade of intermittent electricity outages, while elsewhere in Africa coal projects face scrutiny from lenders, because the utility can’t meet national demand. The government last year said municipalities could find alternative suppliers.

Earlier this month Ethekwini, the municipal area that includes the city of Durban, issued a request for information for the provision of 400 megawatts of power, similar to BC Hydro’s call for power driven by EV uptake.

The City of Johannesburg will in September seek information and proposals for the construction of a 150-megawatt solar plant, reflecting moves like Ontario’s new wind and solar procurements to tackle supply gaps, 50 megawatts of rooftop solar panels and the refurbishment of an idle gas-fired plant that could generate 20 megawatts, it said in June. It will also seek information for the installation of 100 megawatts of battery storage.

Cape Town, which uses a peak of 1,800 megawatts of electricity in winter, hopes to start generating some of its own power next year, aligning with SaskPower’s 2030 renewables plan seen in Canada, according to a statement that accompanied its request for financing proposals.
 

 

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Europe Stores Electricity in Natural Gas Pipes

Power-to-gas converts surplus renewable electricity into green hydrogen or synthetic methane via electrolysis and methanation, enabling seasonal energy storage, grid balancing, hydrogen injection into gas pipelines, and decarbonization of heat, transport, and industry.

 

Key Points

Power-to-gas turns excess renewable power into hydrogen or methane for storage, grid support, and clean fuel.

✅ Enables hydrogen injection into existing natural gas networks

✅ Balances grids and provides seasonal energy storage capacity

✅ Supplies low-carbon fuels for industry, heat, and heavy transport

 

Last month Denmark’s biggest energy firm, Ørsted, said wind farms it is proposing for the North Sea will convert some of their excess power into gas. Electricity flowing in from offshore will feed on-shore electrolysis plants that split water to produce clean-burning hydrogen, with oxygen as a by-product. That would supply a new set of customers who need energy, but not as electricity. And it would take some strain off of Europe’s power grid as it grapples with an ever-increasing share of hard-to-handle EU wind and solar output on the grid.

Turning clean electricity into energetic gases such as hydrogen or methane is an old idea that is making a comeback as renewable power generation surges and crowds out gas in Europe. That is because gases can be stockpiled within the natural gas distribution system to cover times of weak winds and sunlight. They can also provide concentrated energy to replace fossil fuels for vehicles and industries. Although many U.S. energy experts argue that this “power-to-gas” vision may be prohibitively expensive, some of Europe’s biggest industrial firms are buying in to the idea.

European power equipment manufacturers, anticipating a wave of renewable hydrogen projects such as Ørsted’s, vowed in January that, as countries push for hydrogen-ready power plants across Europe, all of their gas-fired turbines will be certified by next year to run on up to 20 percent hydrogen, which burns faster than methane-rich natural gas. The natural gas distributors, meanwhile, have said they will use hydrogen to help them fully de-carbonize Europe’s gas supplies by 2050.

Converting power to gas is picking up steam in Europe because the region has more consistent and aggressive climate policies and evolving electricity pricing frameworks that support integration. Most U.S. states have goals to clean up some fraction of their electricity supply; coal- and gas-fired plants contribute a little more than a quarter of U.S. greenhouse gas emissions. In contrast, European countries are counting on carbon reductions of 80 percent or more by midcentury—reductions that will require an economywide switch to low-carbon energy.

Cleaning up energy by stripping the carbon out of fossil fuels is costly. So is building massive new grid infrastructure, including transmission lines and huge batteries, amid persistent grid expansion woes in parts of Europe. Power-to-gas may be the cheapest way forward, complementing Germany’s net-zero roadmap to cut electricity costs by a third. “In order to reach the targets for climate protection, we need even more renewable energy. Green hydrogen is perceived as one of the most promising ways to make the energy transition happen,” says Armin Schnettler, head of energy and electronics research at Munich-based electric equipment giant Siemens.

Europe already has more than 45 demonstration projects to improve power-to-gas technologies and their integration with power grids and gas networks. The principal focus has been to make the electrolyzers that convert electricity to hydrogen more efficient, longer-lasting and cheaper to produce.

The projects are also scaling up the various technologies. Early installations converted a few hundred kilowatts of electricity, but manufacturers such as Siemens are now building equipment that can convert 10 megawatts, which would yield enough hydrogen each year to heat around 3,000 homes or fuel 100 buses, according to financial consultancy Ernst & Young.

The improvements have been most dramatic for proton-exchange membrane electrolyzers, which are akin to the fuel cells used in hydrogen vehicles (but optimized to produce hydrogen rather than consume it). The price of proton-exchange electrolyzers has dropped by roughly 40 percent during the past decade, according to a study published in February in Nature Energy. They are also five times more compact than older alkaline electrolysis plants, enabling onsite hydrogen production near gas consumers, and they can vary their power consumption within seconds to operate on fluctuating wind and solar generation.

Many European pilot projects are demonstrating “methanation” equipment that converts hydrogen to methane, too, which can be used as a drop-in replacement for natural gas. Europe’s electrolyzer plants, however, are showing that methanation is not as critical to the power-to-gas vision as advocates long believed. Many electrolyzers are injecting their hydrogen directly into natural gas pipelines—something that U.S. gas firms forbid—and they are doing so without impacting either the gas infrastructure or natural gas consumers.

Europe’s first large-scale hydrogen injection began in eastern Germany in 2013 at a two-megawatt electrolyzer installed by Essen-based power firm E.ON. Germany has since ratcheted up the amount of hydrogen it allows in natural gas lines from an initial 2 percent by volume to 10 percent, in a market where renewables now outpace coal and nuclear in Germany, and other European states have followed suit with their own hydrogen allowances. Christopher Hebling, head of hydrogen technologies at the Freiburg-based Fraunhofer Institute for Solar Energy Systems, predicts that such limits will rise to the 20-percent level anticipated by Europe’s turbine manufacturers.

Moving renewable hydrogen and methane via natural gas pipelines promises to cut the cost of switching to renewable energy. For example, gas networks have storage caverns whose reserves could be tapped to run gas-fired electric generation power plants during periods of low wind and solar output. Hebling notes that Germany’s gas network can store 240 terawatt-hours of energy—roughly 25 times more energy than global power grids can presently store by pumping water uphill to refill hydropower reservoirs. Repurposing gas infrastructure to help the power system could save European consumers 138 billion euros ($156 billion) by 2050, according to Dutch energy consultancy Navigant (formerly Ecofys).

For all the pilot plants and promise, renewable hydrogen presently supplies a tiny fraction of Europe’s gas. And, globally, around 4 percent of hydrogen is supplied via electrolysis, with the bulk refined from fossil fuels, according to the International Renewable Energy Agency.

Power-to-gas is catching up, however. According to the February Nature Energy study, renewable hydrogen already pays for itself in some niche applications, and further electrolyzer improvements will progressively extend its market. “If costs continue to decline as they have done in recent years, power-to-gas will become competitive at large scale within the next decade,” says study co-author Gunther Glenk, an economist at the Technical University of Munich.

Glenk says power-to-gas could scale up faster if governments guaranteed premium prices for renewable hydrogen and methane, as they did to mainstream solar and wind power.

Tim Calver, an energy storage researcher turned consultant and Ernst & Young’s executive director in London, agrees that European governments need to step up their support for power-to-gas projects and markets. Calver calls the scale of funding to date, “not proportionate to the challenge that we face on long-term decarbonization and the potential role of hydrogen.”

 

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U.S. Electricity and natural gas prices explained

Energy Pricing Factors span electricity generation, transmission, and distribution costs, plus natural gas supply-demand, renewables, seasonal peaks, and wholesale pricing effects across residential, commercial, and industrial customers, usage patterns, weather, and grid constraints.

 

Key Points

They are the costs and market forces driving electricity and natural gas prices, from generation to delivery and demand.

✅ Generation, transmission, distribution shape electricity rates

✅ Gas prices hinge on supply, storage, imports/exports

✅ Demand shifts: weather, economy, and fuel alternatives

 

There are a lot of factors that affect energy prices globally. What’s included in the price to heat homes and supply them with electricity may be a lot more than some people may think.

Electricity
Generating electricity is the largest component of its price, according to the U.S. Energy Information Administration (EIA). Generation accounts for 56% of the price of electricity, while distribution and transmission account for 31% and 13% respectively.

Homeowners and businesses pay more for electricity than industrial companies, and U.S. electricity prices have recently surged, highlighting broader inflationary pressures. This is because industrial companies can take electricity at higher voltages, reducing transmission costs for energy companies.

“Industrial consumers use more electricity and can receive it at higher voltages, so supplying electricity to these customers is more efficient and less expensive. The price of electricity to industrial customers is generally close to the wholesale price of electricity,” EIA explains.

NYSEG said based on the average use of 600 kilowatt-hours per month, its customers spent the most money on delivery and transition charges in 2020, 57% or about $42, and residential electricity bills increased 5% in 2022 after inflation, according to national data. They also spent on average 35% (~$26) on supply charges and 8% (~$6) on surcharges.

Electricity prices are usually higher in the summer. Why? Because energy companies use sources of electricity that cost more money. It used to be that renewable sources, like solar and wind, were the most expensive sources of energy but increased technological advances have changed this, according to the International Energy Agency’s 2021 World Energy Outlook.

“In most markets, solar PV or wind now represents the cheapest available source of new electricity generation. Clean energy technology is becoming a major new area for investment and employment – and a dynamic arena for international collaboration and competition,” the report said.

Natural gas
The price of natural gas is driven by supply and demand. If there is more supply, prices are generally lower. If there is not as much supply, prices are generally higher the EIA explains. On the other side of the equation, more demand can also increase the price and less demand can decrease the price.

High natural gas prices mean people turn their home thermostats down a few degrees to save money, so the EIA said reduced demand can encourage companies to produce more natural gas, which would in turn help lower the cost. Lower prices will sometimes cause companies to reduce their production, therefore causing the price to rise.

The three major supply factors that affect prices: the amount of natural gas produced, how much is stored, and the volume of gas imported and exported. The three major demand factors that affect price are: changes in winter/summer weather, economic growth, and the broader energy crisis dynamics, as well as how much other fuels are available and their price, said EIA.

To think the price of natural gas is higher when the economy is thriving may sound counterintuitive but that’s exactly what happens. The EIA said this is because of increases in demand.

 

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Smart grid and system improvements help avoid more than 500,000 outages over the summer

ComEd Smart Grid Reliability drives outage reduction across Illinois, leveraging smart switches, grid modernization, and peak demand programs to keep customers powered, improve power quality, and enhance energy savings during extreme weather and severe storms.

 

Key Points

ComEd's smart grid performance, cutting outages and improving power quality to enhance reliability and customer savings.

✅ Smart switches reroute power to avoid customer interruptions

✅ Fewer outages during extreme weather across northern Illinois

✅ Peak Time Savings rewards for reduced peak demand usage

 

While the summer of 2019 set records for heat and brought severe storms, ComEd customers stayed cool thanks to record-setting reliability during the season. These smart grid investments over the last seven years helped to set records in key reliability measurements, including frequency of outages metrics, and through smart switches that reroute power around potential problem areas, avoided more than 538,000 customer interruptions from June to August.

"In a summer where we were challenged by extreme weather, we saw our smart grid investments and our people continue to deliver the highest levels of reliability, backed by extensive disaster planning across utilities, for the families and businesses we serve," said Joe Dominguez, CEO of ComEd. "We're proud to deliver the most affordable, cleanest and, as we demonstrated this summer, most reliable energy to our customers. I want to thank our 6,000 employees who work around the clock in often challenging conditions to power our communities."

ComEd has avoided more than 13 million customer interruptions since 2012, due in part to smart grid and system improvements. The avoided outages have resulted in $2.4 billion in estimated savings to society. In addition to keeping energy flowing for residents, strong power reliability continues to help persuade industrial and commercial companies to expand in northern Illinois and Chicago. The GridWise Alliance recently recognized Illinois as the No. 2 state in the nation for its smart grid implementation.

"Our smart grid investments has vastly improved the infrastructure of our system," said Terry Donnelly, ComEd president and chief operating officer. "We review the system and our operations continually to make sure we're investing in areas that benefit the greatest number of customers, and to prepare for public-health emergencies as well. On a daily basis and during storms or to reduce wildfire risk when necessary, our customers are seeing fewer and fewer interruptions to their lives and businesses."

ComEd customers also set records for energy savings this summer. Through its Peak Time Savings program and other energy-efficiency programs offered by utilities, ComEd empowered nearly 300,000 families and individuals to lower their bills by a total of more than $4 million this summer for voluntarily reducing their energy use during times of peak demand. Since the Peak Time Savings program launched in 2015, participating customers have earned a total of more than $10 million in bill credits.

 

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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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First Nuclear Reactors Built in 30 Years Take Shape at Georgia Power Plant

Vogtle Units 3 and 4 are Westinghouse AP1000 nuclear reactors under construction in Waynesboro, Georgia, led by Southern Nuclear, Georgia Power, and Bechtel, adding 2,234 MWe of carbon-free baseload power with DOE loan guarantees.

 

Key Points

Vogtle Units 3 and 4 are AP1000 reactors in Georgia delivering 2,234 MWe of low-carbon baseload electricity.

✅ Each unit: Westinghouse AP1000, 1,117 MWe capacity.

✅ Managed by Southern Nuclear, built by Bechtel.

✅ DOE loan guarantees support financing and risk.

 

Construction is ongoing for two new nuclear reactors, Units 3 and 4, at Georgia Power's Alvin W. Vogtle Electric Generating Plant in Waynesboro, Ga. the first new nuclear reactors to be constructed in the United Stated in 30 years, mirroring a new U.S. reactor startup that will provide electricity to more than 500,000 homes and businesses once operational.

Construction on Unit 3 started in March 2013 with an expected completion date of November 2021. For Unit 4, work began in November 2013 with a targeted delivery date of November 2022. Each unit houses a Westinghouse AP1000 (Advanced Passive) nuclear reactor that can generate about 1,117 megawatts (MWe). The reactor pressure vessels and steam generators are from Doosan, a South Korean firm.

The pouring of concrete was delayed to 2013 due to the United States Nuclear Regulatory Commission issuing a license amendment which permitted the use of higher-strength concrete for the foundations of the reactors, eliminating the need to make additional modifications to reinforcing steel bar.

The work is occurring in the middle of an operational nuclear facility, and the construction area contains many cranes and storage areas for the prefabricated parts being installed. Space also is needed for various trucks making deliveries, especially concrete.

The reactor buildings, circular in shape, are several hundred feet apart from one another and each one has an annex building and a turbine island structure. The estimated total price for the project is expected in the $18.7 billion range. Bechtel Corporation, which built Units 1 and 2, was brought in January 2017 to take over the construction that is being overseen by Southern Nuclear Operating Company (SNOC), which operates the plant.

The project will require the equivalent of 3,375 miles of sidewalk; the towers for Units 3 and 4 are 60 stories high and have two million pound CA modules; the office space for both units is 300,000 sq. ft.; and there are more than 8,000 construction workers over 30 percent being military veterans. The new reactors will create 800 permanent jobs.

Southern Nuclear and Georgia Power took over management of the construction project in 2017 after Westinghouse's Chapter 11 bankruptcy. The plant, built in the late 1980s with Unit 1 becoming operational in 1987 and Unit 2 in 1989, is jointly owned by Georgia Power (45.7 percent), Oglethorpe Power Corporation (30 percent), Municipal Electric Authority of Georgia (22.7 percent) and Dalton Utilities (1.6 percent).

"Significant progress has been made on the construction of Vogtle 3 and 4 since the transition to Southern Nuclear following the Westinghouse bankruptcy," said Paul Bowers, Chairman, President and CEO of Georgia Power. "While there will always be challenges in building the first new nuclear units in this country in more than 30 years, we remain focused on reducing project risk and maintaining the current project momentum in order to provide our customers with a new carbon-free energy source that will put downward pressure on rates for 60 to 80 years."

The Vogtle and Hatch nuclear plants currently provide more than 20 percent of Georgia's annual electricity needs. Vogtle will be the only four-unit nuclear facility in the country. The energy is needed to meet the rising demand for electricity as the state expects to have more than four million new residents by 2030.

The plant's expansion is the largest ongoing construction project in Georgia and one of the largest in the state's history, while comparable refurbishments such as the Bruce reactor overhaul progress in Canada. Last March an agreement was signed to secure approximately $1.67 billion in additional Department of Energy loan guarantees. Georgia Power previously secured loan guarantees of $3.46 billion.

The signing highlighted the placement of the top of the containment vessel for Unit 3, echoing the Hinkley Point C roof lift seen in the U.K., which signified that all modules and large components had been placed inside it. The containment vessel is a high-integrity steel structure that houses critical plant components. The top head is 130 ft. in diameter, 37 ft. tall, and weighs nearly 1.5 million lbs. It is comprised of 58 large plates, welded together with each more than 1.5 in. thick.

"From the very beginning, public and private partners have stood with us," said Southern Company Chairman, President and CEO Tom Fanning. "Everyone involved in the project remains focused on sustaining our momentum."

Bechtel has completed more than 80 percent of the project, and the major milestones for 2019 have been met, aligning with global nuclear milestones reported across the industry, including setting the Unit 4 pressurizer inside the containment vessel last February, which will provide pressure control inside the reactor coolant system. More specialized construction workers, including craft labor, have been hired via the addition of approximately 300 pipefitters and 350 electricians since November 2018. Another 500 to 1,000 craft workers have been more recently brought in.

A key accomplishment occurred last December when 1,300 cu. yds. of concrete were poured inside the Unit 4 containment vessel during a 21-hour operation that involved more than 100 workers and more than 120 truckloads of concrete. In 2018 alone, more than 23,000 cu. yds. of concrete were poured part of the nearly 600,000 cu. yds. placed since construction started, and the installation of more than 16,200 yds. of piping.

Progress also has been solid for Unit 3. Last January the integrated head package (IHP) was set inside the containment vessel. The IHP, weighing 475,000 lbs. and standing 48 ft. tall, combines several separate components in one assembly and allows the rapid removal of the reactor vessel head during a refueling outage. One month earlier, the placement of the third and final ring for containment vessel, and the placement of the fourth and final reactor coolant pump (RCP, 375,000 lbs.), were executed.

"Weighing just under 2 million pounds, approximately 38 feet high and with a diameter of 130 feet, the ring is the fourth of five sections that make up the containment vessel," stated a Georgia Power press release. "The RCPs are mounted to the steam generator and serve a critical part of the reactor coolant system, circulating water from the steam generator to the reactor vessel, allowing sufficient heat transfer for safe plant operation. In the same month, the Unit 3 shield building with additional double-decker panels, was placed.

According to a construction update from Georgia Power, a total of eight six-panel sections have been placed, with each one measuring 20 ft. tall and 114 ft. wide, weighing up to 300,000 lbs. To date, more than half of the shield building panels have been placed for Unit 3. The shield building panels, fabricated in Newport News, Va., provide structural support to the containment cooling water supply and protect the containment vessel, which houses the reactor vessel.

Building the reactors is challenging due to the design, reflecting lessons from advanced reactors now being deployed. Unit 3 will have 157 fuel assemblies, with each being a little over 14 ft. long. They are crucial to fuelling the reactor, and once the initial fueling is completed, nearly one-third of the fuel assemblies will be replaced for each re-fuelling operation. In addition to the Unit 3 containment top, placement crews installed three low-pressure turbine rotors and the generator rotor inside the unit's turbine building.

Last November, major systems testing got underway at Unit 3 as the site continues to transition from construction toward system operations. The Open Vessel Testing will demonstrate how water flows from the key safety systems into the reactor vessel ensuring the paths are not blocked or constricted.

"This is a significant step on our path towards operations," said Glen Chick, Vogtle 3 & 4 construction executive vice president. "[This] will prepare the unit for cold hydro testing and hot functional testing next year both critical tests required ahead of initial fuel load."

It also confirms that the pumps, motors, valves, pipes and other components function as designed, a reminder of how issues like the South Carolina plant leak can disrupt operations when systems falter.

"It follows the Integrated Flush process, which began in August, to push water through system piping and mechanical components that feed into the Unit 3 reactor vessel and reactor coolant loops for the first time," stated a press release. "Significant progress continues ... including the placement of the final reinforced concrete portion of the Unit 4 shield building. The 148-cubic yard placement took eight hours to complete and, once cured, allows for the placement of the first course of double-decker panels. Also, the upper inner casing for the Unit 3 high-pressure turbine has been placed, signifying the completion of the centerline alignment, which will mean minimal vibration and less stress on the rotors during operations, resulting in more efficient power generation."

The turbine rotors, each weighing approximately 200 tons and rotating at 1,800 revolutions per-minute, pass steam through the turbine blades to power the generator.

The placement of the middle containment vessel ring for Unit 4 was completed in early July. This required several cranes to work in tandem as the 51-ft. tall ring weighed 2.4 million lbs. and had dozens of individual steel plates that were fabricated on site.

A key part of the construction progress was made in late July with the order of the first nuclear fuel load for Unit 3, which consists of 157 fuel assemblies with each measuring 14 ft. tall.

On May 7, Unit 3 was energized (permanently powered), which was essential to perform the testing for the unit. Prior to this, the plant equipment had been running on temporary construction power.

"[This] is a major first step in transitioning the project from construction toward system operations," Chick said.

Construction of the north side of the Unit 3 Auxiliary Building (AB) has progressed with both the floor and roof modules being set. Substantial work also occurred on the steel and concrete that forms the remaining walls and the north AB roof at elevation.

 

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