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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Cheap material converts heat to electricity

Polycrystalline Tin Selenide Thermoelectrics enable waste heat recovery with ZT 3.1, matching single crystals while cutting costs, powering greener car engines, industrial furnaces, and thermoelectric generators via p-type and emerging n-type designs.

 

Key Points

Low-cost tin selenide devices that turn waste heat into power, achieving ZT 3.1 and enabling p-type and n-type modules.

✅ Oxygen removal prevents heat-leaking tin oxide grain skins.

✅ Polycrystalline ingots match single-crystal ZT 3.1 at lower cost.

✅ N-type tin selenide in development to pair with p-type.

 

So-called thermoelectric generators turn waste heat into electricity without producing greenhouse gas emissions, providing what seems like a free lunch. But despite helping power the Mars rovers, the high cost of these devices has prevented their widespread use. Now, researchers have found a way to make cheap thermoelectrics that work just as well as the pricey kind. The work could pave the way for a new generation of greener car engines, industrial furnaces, and other energy-generating devices.

“This looks like a very smart way to realize high performance,” says Li-Dong Zhao, a materials scientist at Beihang University who was not involved with the work. He notes there are still a few more steps to take before these materials can become high-performing thermoelectric generators. However, he says, “I think this will be used in the not too far future.”

Thermoelectrics are semiconductor devices placed on a hot surface, like a gas-powered car engine or on heat-generating electronics using thin-film converters to capture waste heat. That gives them a hot side and a cool side, away from the hot surface. They work by using the heat to push electrical charges from one to the other, a process of turning thermal energy into electricity that depends on the temperature gradient. If a device allows the hot side to warm up the cool side, the electricity stops flowing. A device’s success at preventing this, as well as its ability to conduct electrons, feeds into a score known as the figure of merit, or ZT.

 Over the past 2 decades, researchers have produced thermoelectric materials with increasing ZTs, while related advances such as nighttime solar cells have broadened thermal-to-electric concepts. The record came in 2014 when Mercouri Kanatzidis, a materials scientist at Northwestern University, and his colleagues came up with a single crystal of tin selenide with a ZT of 3.1. Yet the material was difficult to make and too fragile to work with. “For practical applications, it’s a non-starter,” Kanatzidis says.

So, his team decided to make its thermoelectrics from readily available tin and selenium powders, an approach that, once processed, makes grains of polycrystalline tin selenide instead of the single crystals. The polycrystalline grains are cheap and can be heated and compressed into ingots that are 3 to 5 centimeters long, which can be made into devices. The polycrystalline ingots are also more robust, and Kanatzidis expected the boundaries between the individual grains to slow the passage of heat. But when his team tested the polycrystalline materials, the thermal conductivity shot up, dropping their ZT scores as low as 1.2.

In 2016, the Northwestern team discovered the source of the problem: an ultrathin skin of tin oxide was forming around individual grains of polycrystalline tin selenide before they were pressed into ingots. And that skin acted as an express lane for the heat to travel from grain to grain through the material. So, in their current study, Kanatzidis and his colleagues came up with a way to use heat to drive any oxygen away from the powdery precursors, leaving pristine polycrystalline tin selenide, whereas other devices can generate electricity from thin air using ambient moisture.

The result, which they report today in Nature Materials, was not only a thermal conductivity below that of single-crystal tin selenide but also a ZT of 3.1, a development that echoes nighttime renewable devices showing electricity from cold conditions. “This opens the door for new devices to be built from polycrystalline tin selenide pellets and their applications to be explored,” Kanatzidis says.

Getting through that door will still take some time. The polycrystalline tin selenide the team makes is spiked with sodium atoms, creating what is known as a “p-type” material that conducts positive charges. To make working devices, researchers also need an “n-type” version to conduct negative charges.

Zhao’s team recently reported making an n-type single-crystal tin selenide by spiking it with bromine atoms. And Kanatzidis says his team is now working on making an n-type polycrystalline version. Once n-type and p-type tin selenide devices are paired, researchers should have a clear path to making a new generation of ultra-efficient thermoelectric generators. Those could be installed everywhere from automobile exhaust pipes to water heaters and industrial furnaces to scavenge energy from some of the 65% of fossil fuel energy that winds up as waste heat. 

 

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Alberta Electricity market needs competition

Alberta Electricity Market faces energy-only vs capacity debate as transmission, distribution, and administration fees surge; rural rates rise amid a regulated duopoly of investor-owned utilities, prompting calls for competition, innovation, and lower bills.

 

Key Points

Alberta's electricity market is an energy-only system with rising delivery charges and limited rural competition.

✅ Energy-only design; capacity market scrapped

✅ Delivery charges outpace energy on monthly bills

✅ Rural duopoly limits competition and raises rates

 

Last week, Alberta’s new Energy Minister Sonya Savage announced the government, through its new electricity rules, would be scrapping plans to shift Alberta’s electricity to a capacity market and would instead be “restoring certainty in the electricity system.”


The proposed transition from energy only to a capacity market is a contentious subject as a market reshuffle unfolds across the province that many Albertans probably don’t know much about. Our electricity market is not a particularly glamorous subject. It’s complicated and confusing and what matters most to ordinary Albertans is how it affects their monthly bills.


What they may not realize is that the cost of their actual electricity used is often just a small fraction of their bill amid rising electricity prices across the province. The majority on an average electricity bill is actually the cost of delivering that electricity from the generator to your house. Charges for transmission, distribution and franchise and administration fees are quickly pushing many Alberta households to the limit with soaring bills.


According to data from Alberta’s Utilities Consumer Advocate (UCA), and alongside policy changes, in 2004 the average monthly transmission costs for residential regulated-rate customers was below $2. In 2018 that cost was averaging nearly $27 a month. The increase is equally dramatic in distribution rates which have more than doubled across the province and range wildly, averaging from as low as $10 a month in 2004 to over $80 a month for some residential regulated-rate customers in 2018.


Where you live determines who delivers your electricity. In Alberta’s biggest cities and a handful of others the distribution systems are municipally owned and operated. Outside those select municipalities most of Alberta’s electricity is delivered by two private companies which operate as a regulated duopoly. In fact, two investor-owned utilities deliver power to over 95 per cent of rural Alberta and they continue to increase their share by purchasing the few rural electricity co-ops that remained their only competition in the market. The cost of buying out their competition is then passed on to the customers, driving rates even higher.


As the CEO of Alberta’s largest remaining electricity co-op, I know very well that as the price of materials, equipment and skilled labour increase, the cost of operating follows. If it costs more to build and maintain an electricity distribution system there will inevitably be a cost increase passed on to the consumer. The question Albertans should be asking is how much is too much and where is all that money going with these private- investor-owned utilities, as the sector faces profound change under provincial leadership?


The reforms to Alberta’s electricity system brought in by Premier Klein in the late 1900s and early 2000s contributed to a surge in investment in the sector and led to an explosion of competition in both electricity generation and retail. 


More players entered the field which put downward pressure on electricity rates, encouraged innovation and gave consumers a competitive choice, even as a Calgary electricity retailer urged the government to scrap the overhaul. But the legislation and regulations that govern rural electricity distribution in Alberta continue to facilitate and even encourage the concentration of ownership among two players which is certainly not in the interests of rural Albertans.


It is also not in the spirit of the United Conservative Party platform commitment to a “market-based” system. A market-based system suggests more competition. Instead, what we have is something approaching a monopoly for many Albertans. The UCP promised a review of the transition to a capacity market that would determine which market would be best for Alberta, and through proposed electricity market changes has decided that we will remain an energy-only market.
Consumers in rural Alberta need electricity to produce the goods that power our biggest industries. Instead of regulating and approving continued rate increases from private multinational corporations, we need to drive competition and innovation that can push rates down and encourage growth and investment in rural-based industries and communities.

 

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U.S. Senate Looks to Modernize Renewable Energy on Public Land

PLREDA 2019 advances solar, wind, and geothermal on public lands, guiding DOI siting, improving transmission access, streamlining permitting, sharing revenues, and funding conservation to meet climate goals while protecting wildlife and recreation.

 

Key Points

A bipartisan bill to expand renewables on public lands fund conservation, speed permitting and advance U.S. climate aims.

✅ Targets 25 GW of public-land renewables by 2025

✅ Establishes wildlife conservation and recreation access funds

✅ Streamlines siting, transmission, and equitable revenue sharing

 

The Senate unveiled its version of a bill the House introduced in July to help the U.S. realize the extraordinary renewable energy potential of our shared public lands.

Senator Martha McSally (R-AZ) and a bipartisan coalition of western Senators introduced a Senate version of draft legislation that will help the Department of the Interior tap the renewable energy potential of our shared public lands. The western Senators represent Arizona, New Mexico, Colorado, Montana, and Idaho.

Elsewhere in the West, lawmakers have moved to modernize Oregon hydropower to streamline licensing, signaling broad regional momentum.

The Public Land Renewable Energy Development Act of 2019 (PLREDA) facilitates siting of solar, wind, and geothermal energy projects on public lands, boosts funding for conservation, and promotes ambitious renewable energy targets that will help the U.S. take action on the climate crisis.

Like the House version, the Senate bill enjoys strong bi-partisan support and industry endorsement. The Senate version makes few notable changes to the bill introduced in July by Representatives Mike Levin (D-CA) and Paul Gosar (R-AZ). It includes:

  • A commitment to enhance natural resource conservation and stewardship via the establishment of a fish and wildlife conservation fund that would support conservation and restoration work and other important stewardship activities.
  • An ambitious renewable energy production goal for the Department of the Interior to permit a total of 25 gigawatts of renewable energy on public lands by 2025—nearly double the current generating capacity of projects currently on our public lands.
  • Establishment of criteria for identifying appropriate areas for renewable energy development using the 2012 Western Solar Plan as a model. Key criteria to be considered include access to transmission lines and likelihood of avoiding or minimizing conflict with wildlife habitat, cultural resources, and other resources and values.
  • Improved public access to Federal lands for recreational uses via funds made available for preserving and improving access, including enhancing public access to places that are currently inaccessible or restricted.
  • Sharing of revenues raised from renewable energy development on public lands in an equitable manner that benefits local communities near new renewable energy projects and supports the efficient administration of permitting requirements.
  • Creating incentives for renewable energy development by giving Interior the authority to reduce rental rates and capacity fees to ensure new renewable energy development remains competitive in the marketplace.

NRDC strongly supports this legislation, and we will do our utmost to facilitate its passage into law. There is no question that in our era of runaway climate change, legislation that balances energy production with environmental conservation and stewardship of our public lands is critical.

PLREDA takes a balanced approach to using our public lands to help lead the U.S. toward a low-carbon future, as states pursue 100% renewable electricity goals nationwide. The bill outlines a commonsense approach for federal agencies to play a meaningful role in combatting climate change.

 

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Tesla (TSLA) Wants to Become an Electricity Retailer

Tesla Energy Ventures Texas enters the deregulated market as a retail electricity provider, leveraging ERCOT, battery storage, solar, and grid software to enable virtual power plants and customer energy trading with Powerwall and Megapack assets.

 

Key Points

Tesla Energy Ventures Texas is Tesla's retail power unit selling grid and battery energy and enabling solar exports.

✅ ERCOT retail provider; sells grid and battery-stored power

✅ Uses Powerwall/Megapack; supports virtual power plants

✅ Targets Tesla owners; enables solar export and trading

 

Last week, Tesla Energy Ventures, a new subsidiary of electric car maker Tesla Inc. (TSLA), filed an application to become a retail electricity provider in the state of Texas. According to reports, the company plans to sell electricity drawn from the grid to customers and from its battery storage products. Its grid transaction software may also enable customers for its solar panels to sell excess electricity back to the smart grid in Texas.1

For those who have been following Tesla's fortunes in the electric car industry, the Palo Alto, California-based company's filing may seem baffling. But the move dovetails with Tesla's overall ambitions for its renewable energy business, as utilities face federal scrutiny of climate goals and electricity rates.

Why Does Tesla Want to Become an Electricity Provider?
The simple answer to that question is that Tesla already manufactures devices that produce and store power. Examples of such devices are its electric cars, which come equipped with lithium ion batteries, and its suite of battery storage products for homes and enterprises. Selling power generated from these devices to consumers or to the grid is a logical next step.


Tesla's move will benefit its operations. The filing states that it plans to build a massive battery storage plant near its manufacturing facility in Austin. The plant will provide the company with a ready and cheap source of power to make its cars.

Tesla's filing should also be analyzed in the context of the Texas grid. The state's electricity market is fully deregulated, unlike regions debating grid privatization approaches, and generated about a quarter of its overall power from wind and solar in 2020.2 The Biden administration's aggressive push toward clean energy is only expected to increase that share.

After a February fiasco in the state grid resulted in a shutdown of renewable energy sources and skyrocketing natural gas prices, Texas committed to boosting the role of battery storage in its grid. The Electricity Reliability Council of Texas (ERCOT), the state's grid operator, has said it plans to install 3,008 MW of battery storage by the end of 2022, a steep increase from the 225 MW generated at the end of 2020.3 ERCOT's proposed increase in installation represents a massive market for Tesla's battery unit.

Tesla already has considerable experience in this arena. It has built battery storage plants in California and Australia and is building a massive battery storage unit in Houston, according to a June Bloomberg report.4 The unit is expected to service wholesale power producers. Besides this, the company plans to "drum up" business among existing customers for its batteries through an app and a website that will allow them to buy and sell power among themselves, a model also being explored by Octopus Energy in international talks.

Tesla Energy Ventures: A Future Profit Center?
Tesla's foray into becoming a retail electricity provider could boost the top line for its energy services business, even as issues like power theft in India highlight retail market challenges. In its last reported quarter, the company stated that its energy generation and storage business brought in $810 million in revenues.

Analysts have forecast a positive future for its battery storage business. Alex Potter from research firm Piper Sandler wrote last year that battery storage could bring in more than $200 billion per year in revenue and grow up to a third of the company's overall business.5

Immediately after the news was released, Morningstar analyst Travis Miller wrote that Tesla does not represent an immediate threat to other major players in Texas's retail market, where providers face strict notice obligations illustrated when NT Power was penalized for delayed disconnection notices, such as NRG Energy, Inc. (NRG) and Vistra Corp. (VST). According to him, the company will initially target its own customers to "complement" its offerings in electric cars, battery, charging, and solar panels.6

Further down the line, however, Tesla's brand name and resources may work to its advantage. "Tesla's brand name recognition gives it an advantage in a hypercompetitive market," Miller wrote, adding that the car company's entry confirmed the firm's view that consumer technology or telecom companies will try to enter retail energy markets, where policy shifts like Ontario rate reductions can shape customer expectations.

 

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NL Consumer Advocate says 18% electricity rate hike 'unacceptable'

Newfoundland and Labrador electricity rate hike examines a proposed 18.6% increase under the PUB's Rate Stabilization Plan, driven by oil prices at Holyrood, with Consumer Advocate concerns over rate shock and use of RSP balances.

 

Key Points

A proposed 18.6% July 2017 increase under the RSP, driven by oil prices, now under PUB review for potential mitigation.

✅ PUB flags potential rate shock from proposed adjustment

✅ RSP balances cited to offset increases without depleting fund

✅ Oil-fired Holyrood volatility drives fuel cost uncertainty

 

How much of a rate hike is reasonable for users of electricity in Newfoundland and Labrador?

That's a question before the Public Utilities Board (PUB) as it examines an application by Newfoundland and Labrador Hydro, which could see consumers pay up to 18.6 per cent more as of July 1, reflecting regional pressures seen in Nova Scotia, where regulators approved a 14% rate hike earlier this year.

"The estimated rate increase for July 2017 is such a significant increase that it may be argued that it would cause rate shock," said the PUB, asking the company to revise its application.

NL Hydro said the price adjustment is part of what happens every year through the Rate Stabilization Plan (RSP), which is used to offset the ups and downs of oil prices.

"The cost of fuel is volatile and as long as we rely on oil-fired generation at Holyrood, customers will continue to be impacted by this electricity price uncertainty," said the company in a statement to CBC News.

It noted that customers received a break from RSP adjustments in 2015 and 2016, even as costs from the Muskrat Falls project begin to be reflected.

The PUB noted that under the rate stabilization plan, prices have gone up or down by about 10 per cent in the past.

The regulatory board said the impact of the latest request would be a 27.6 per cent hike to Newfoundland Power, with "an estimated average end customer impact of 18.6 per cent."

Hydro's estimates are based on an average price for oil of $81.40 per barrel from July 2017 to June 2018, according to the PUB.

 

'Unacceptable' burden: Consumer Advocate

"To burden ratepayers with an 18 per cent rate increase is unacceptable," said Consumer Advocate Dennis Browne, echoing pushback in Nova Scotia, where the premier urged regulators to reject a 14% hike at the time.

Browne is arguing that there is money in the RSP to reduce the proposed increase, including the possibility of a lump-sum bill credit for customers.

"These ratepayer balances — which, according to NL Power, totals $77.4 million — are not the property of Hydro," he wrote in a letter to the PUB.

"No utility has the right to squirrel away ratepayers' money to be used by that utility for some future purpose. The Board has jurisdiction over those balances," Browne said.

Browne also wants the RSP overhauled so that it can be applied to price fluctuations every quarter, as opposed to annually.

Hydro has expressed concern that depleting the rate stabilization fund would lead to other, more significant, rate increases in the future.

It said several alternatives to mitigate high rates have been provided to the PUB, which has final say, similar to how Manitoba Hydro scaled back a planned increase in the next year.

 

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Wyoming wind boost for US utility

Black Hills Energy Corriedale Wind Farm Expansion earns regulatory approval in Wyoming, boosting capacity to over 52MW near Cheyenne with five turbines, supporting Renewable Ready customers and wind power goals under PUC and PSC oversight.

 

Key Points

An approved Wyoming wind project upgrade to over 52MW, adding five turbines to serve Renewable Ready customers.

✅ Adds 12.5MW via five new wind turbines near Cheyenne

✅ Cost increases to $79m; prior estimate $57m

✅ Approved by SD PUC after Wyoming PSC review

 

US company Black Hills Energy has received regulatory approval to increase the size of its Corriedale wind farm in Wyoming, where Wyoming wind exports to California are advancing, to over 52MW from 40MW previously.

The South Dakota Public Utilities Commission approved the additional 12.5MW capacity after the Wyoming Public Service Commission determined the boost was within commission rules, as federal initiatives like DOE wind energy awards continue to support the sector.

Black Hills Energy will install five additional turbines, raising the project cost to $79m from $57m, amid growing heartland wind investment across the region.
Corriedale will be built near Cheyenne and is expected to be placed in service in late 2020.

Similar market momentum is seen in Canada, where a Warren Buffett-linked Alberta wind farm is planned to expand capacity across the region.

Black Hills said that during the initial subscription period for its Renewable Ready program, applications of interest from eligible commercial, industrial and governmental agency customers were received in excess of the program's 40MW, underscoring the view that more energy sources can make stronger projects.

Black Hills Corporations chief executive and president Linden Evans said: “We are pleased with the opportunity to expand our Renewable Ready program, allowing us to meet our customers’ interest in renewable wind energy, which co-op members increasingly support.

“This innovative program expands our clean energy portfolio while meeting our customers’ evolving needs, particularly around cleaner and more sustainable energy, as projects like new energy generation coming online demonstrate.”

 

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