S-PRO tests well to control harmonic oscillations

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Although wind farms provide clean, green power – they do pose one problem for utilities: harmonic oscillations.

Since wind farms are generally located far away from load centers, power flow is increased using series capacitors to compensate for transmission line reactance. Unfortunately series capacitors can interact with the wind system, creating undamped sub-harmonic current oscillations that can cause serious damage to wind turbine controllers and also to conventional generators.

The wind turbine's own mechanical system interactions tower-to-blade can also generate sub-harmonics, which are detrimental to induction generators, transformers, and may cause resonance at the point of common coupling in the electrical grid. By isolating the healthy grid from sub-harmonic generation sources, damage to the electrical interconnection can be prevented.

ERLPhase Power Technologies recently announced the S-PRO Sub-Harmonic Protection Relay is proving itself to help control harmonic oscillations at a Minnesota wind farm.

“The S-PRO was installed at a wind farm substation in Trimont, Minnesota to detect subharmonic oscillations occurring at adjacent wind farms connected to the series compensated line,” said Pratap Mysore, Consulting Engineer at Xcel Energy. “In tests so far, the unit has performed well and the relay has been designed well to detect and protect against sustained harmonics from the wind turbines.”

The S-PRO 4000 relay provides real-time processing of voltage and current signals with sub-harmonic monitoring at 1 Hz intervals between 5 and 25 Hz 5 Hz, 6 Hz, 7 HzÂ… 23 Hz, 24 Hz and 25 Hz. It protects the grid from sub-harmonic oscillations at the point-of-common-coupling every 1 second, with additional user-configurable delays.

“Our sub-harmonic protection relay S-PRO is the first advanced microprocessor-based relay with 10 second high speed recording capability. It can also be used for detecting Sub Synchronous Resonance SSR frequencies,” commented Krish Narendra, Vice President of Technology and Quality at ERLPhase.

ERLPhase has a history of pioneering innovative protection and monitoring solutions including transformer loss-of-life monitoring in the T-PRO Transformer Protection Relay, dynamic swing recording in the L-PRO Transmission Line Protection Relay, the use of low impedance current inputs in the B-PRO Bus Protection Relay, and dynamic swing record capture with cross triggering in the TESLA Power System Recorder. All these innovations now find wide spread industry application.

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Atlantic grids, forestry, coastlines need rethink in era of intense storms: experts

Atlantic Canada Hurricane Resilience focuses on climate change adaptation: grid hardening, burying lines, coastline resiliency to sea-level rise, mixed forests, and aggressive tree trimming to reduce outages from hurricane-force winds and post-tropical storms.

 

Key Points

A strategy to harden grids, protect coasts, and manage forests to limit hurricane damage across Atlantic Canada.

✅ Grid hardening and selective undergrounding to cut outage risk.

✅ Coastal defenses: seawalls, dikes, and shoreline vegetation upgrades.

✅ Mixed forests and proactive tree trimming to reduce windfall damage.

 

In an era when storms with hurricane-force winds are expected to keep battering Atlantic Canada, experts say the region should make major changes to electrical grids, power utilities and shoreline defences and even the types of trees being planted.

Work continues today to reconnect customers after post-tropical storm Dorian knocked out power to 80 per cent of homes and businesses in Nova Scotia. By early afternoon there were 56,000 customers without electricity in the province, compared with 400,000 at the storm's peak on the weekend, a reminder that major outages can linger long after severe weather.

Recent scientific literature says 35 hurricanes -- not including post-tropical storms like Dorian -- have made landfall in the region since 1850, an average of one every five years that underscores the value of interprovincial connections like the Maritime Link for reliability.

Heavy rains and strong winds batter Shelburne, N.S. on Saturday, Sept. 7, 2019 as Hurricane Dorian approaches, making storm safety practices crucial for residents. (Suzette Belliveau/ CTV Atlantic)

Anthony Taylor, a forest ecologist scientist with Natural Resources Canada, wrote in a recent peer-reviewed paper that climate change is expected to increase the frequency of severe hurricanes.

He says promoting more mixed forests with hardwoods would reduce the rate of destruction caused by the storms.

Erni Wiebe, former director of distribution at Manitoba Hydro, says the storms should cause Atlantic utilities to rethink their view that burying lines is too expensive and to contemplate other long-term solutions such as the Maritime Link that enhance grid resilience.

Blair Feltmate, head of the Intact Centre on Climate Change at the University of Waterloo, says Atlantic Canada should also develop standards for coastline resiliency due to predictions of rising sea levels combining with the storms, while considering how delivery rate changes influence funding timelines.

He says that would mean a more rapid refurbishing of sea walls and dike systems, along with more shoreline vegetation.

Feltmate also calls for an aggressive tree-trimming program to limit power outages that he says "will otherwise continue to plague the Maritimes," while addressing risks like copper theft through better security.

 

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U.S. residential electricity bills increased 5% in 2022, after adjusting for inflation

U.S. Residential Electricity Bills rose on stronger demand, inflation, and fuel costs, with higher retail prices, kWh consumption, and extreme weather driving 2022 spikes; forecasts point to stable summer usage and slight price increases.

 

Key Points

They are average household power costs shaped by prices, kWh use, weather, and upstream fuel costs.

✅ 2022 bills up 13% nominal, 5% real vs. 2021

✅ Retail price rose 11%; consumption up 2% to 907 kWh

✅ Fuel costs to plants up 34%, pressuring rates

 

In nominal terms, the average monthly electricity bill for residential customers in the United States increased 13% from 2021 to 2022, rising from $121 a month to $137 a month. After adjusting for inflation—which reached 8% in 2022, a 40-year high—electricity bills increased 5%. Last year had the largest annual increase in average residential electricity spending since we began calculating it in 1984. The increase was driven by a combination of more extreme temperatures, which increased U.S. consumption of electricity for both heating and cooling, and higher fuel costs for power plants, which drove up retail electricity prices nationwide.

Residential electricity customers’ monthly electricity bills are based on the amount of electricity consumed and the retail electricity price. Average U.S. monthly electricity consumption per residential customer increased from 886 kilowatthours (kWh) in 2021 to 907 kWh in 2022, even as U.S. electricity sales have declined over the past seven years. Both a colder winter and a hotter summer contributed to the 2% increase in average monthly electricity consumption per residential customer in 2022 because customers used more space heating during the winter and more air conditioning during the summer, with some states, such as Pennsylvania, facing sharp winter rate increases.

Although we don’t directly collect retail electricity prices, we do collect revenues from electricity providers that allow us to determine prices by dividing by consumption, and industry reports show major utilities spending more on electricity delivery than on power production. In 2022, the average U.S. residential retail electricity price was 15.12 cents/kWh, an 11% increase from 13.66 cents/kWh in 2021. After adjusting for inflation, U.S. residential electricity prices went up by 2.5%.

Higher fuel costs for power plants drove the increase in residential retail electricity prices. The cost of fossil fuels—including natural gas prices, coal, and petroleum—delivered to U.S. power plants increased 34%, from $3.82 per million British thermal units (MMBtu) in 2021 to $5.13/MMBtu in 2022. The higher fuel costs were passed along to residential customers and contributed to higher retail electricity prices, and Germany power prices nearly doubled over a year in a related trend.

In the first three months of 2023, the average U.S. residential monthly electricity bill was $133, or 5% higher than for the same time last year, according to data from our Electric Power Monthly. The increase was driven by a 13% increase in the average U.S. residential retail electricity price, which was partly offset by a 7% decrease in average monthly electricity consumption per residential customer, and industry outlooks also see U.S. power demand sliding 1% on milder weather. This summer, we expect that typical household electricity bills will be similar to last year’s, with customers paying about 2% more on average. The slight increase in electricity costs forecast for this summer stems from higher retail electricity prices but similar consumption levels as last summer.
 

 

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Kenya on Course for $5 Billion Nuclear Plant to Power Industry

Kenya Nuclear Power Plant Project advances with environmental impact assessment, selecting Tana River County under a build-operate-transfer model to boost grid capacity, support manufacturing growth, and assess reactor technology for reliable baseload energy.

 

Key Points

A $5B BOT nuclear facility in Tana River to expand Kenya's grid, aiming to start operations in about seven years.

✅ Environmental impact study published for public review by NEMA

✅ Preferred site: Tana River County near coast; grid integration

✅ BOT concession; reactor tech under evaluation for baseload

 

Kenya’s nuclear agency submitted impact studies for a $5 billion power plant, and said it’s on course to build and start operating the facility in about seven years, as markets like China's nuclear program continue steady expansion.

The government plans to expand its nuclear-power capacity fourfold by 2035, mirroring policy steps in India to revive the sector, the Nuclear Power and Energy Agency said in a report on the National Environment Management Authority’s website. The document is set for public scrutiny before the environmental watchdog can approve it, aligning with global green industrial strategies that weigh nuclear in decarbonization, and pave the way for the project to continue.

President Uhuru Kenyatta wants to ramp up installed generation capacity from 2,712 megawatts as of April to boost manufacturing in East Africa’s largest economy, noting milestones such as Barakah Unit 1 reaching 100% power as indicators of nuclear readiness. Kenya expects peak demand to top 22,000 megawatts by 2031, and other jurisdictions, such as Ontario's exploration of new nuclear, are weighing similar large-scale options, partly due to industrial expansion, a component in Kenyatta’s Big Four Agenda. The other three are improving farming, health care and housing.

The nuclear agency is assessing technologies “to identify the ideal reactor for the country,” it said in the report, including next-gen nuclear designs now being evaluated.

A site in Tana River County, near the Kenyan coast was preferred after studies across three regions, according to the report. The plant will be developed with a concessionaire under a build, operate and transfer model, with innovators such as mini-reactor concepts informing vendor options.

 

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Court reinstates constitutional challenge to Ontario's hefty ‘global adjustment’ electricity charge

Ontario Global Adjustment Charge faces constitutional scrutiny as a regulatory charge vs tax; Court of Appeal revives case over electricity pricing, feed-in tariff contracts, IESO policy, and hydro rate impacts on consumers and industry.

 

Key Points

A provincial electricity fee funding generator contracts, now central to a court fight over tax versus regulatory charge.

✅ Funds gap between market price and contracted generator rates

✅ At issue: regulatory charge vs tax under constitutional law

✅ Linked to feed-in tariff, IESO policy, and hydro rate hikes

 

Ontario’s court of appeal has decided that a constitutional challenge of a steep provincial electricity charge should get its day in court, overturning a lower-court judgment that had dismissed the legal bid.

Hamilton, Ont.-based National Steel Car Ltd. launched the challenge in 2017, saying Ontario’s so-called global adjustment charge was unconstitutional because it is a tax — not a valid regulatory charge — that was not passed by the legislature.

The global adjustment funds the difference between the province’s hourly electricity price and the price guaranteed under contracts to power generators. It is “the component that covers the cost of building new electricity infrastructure in the province, maintaining existing resources, as well as providing conservation and demand management programs,” the province’s Independent Electricity System Operator says.

However, the global adjustment now makes up most of the commodity portion of a household electricity bill, and its costs have ballooned, as regulators elsewhere consider a proposed 14% rate hike in Nova Scotia.

Ontario’s auditor general said in 2015 that global adjustment fees had increased from $650 million in 2006 to more than $7 billion in 2014. She added that consumers would pay $133 billion in global adjustment fees from 2015 to 2032, after having already paid $37 billion from 2006 to 2014.

National Steel Car, which manufactures steel rail cars and faces high electricity rates that hurt Ontario factories, said its global adjustment costs went from $207,260 in 2008 to almost $3.4 million in 2016, according to an Ontario Court of Appeal decision released on Wednesday.

The company claimed the global adjustment was a tax because one of its components funds electricity procurement contracts under a “feed-in tariff” program, or FIT, which National Steel Car called “the main culprit behind the dramatic price increases for electricity,” the decision said.

Ontario’s auditor general said the FIT program “paid excessive prices to renewable energy generators.” The program has been ended, but contracts awarded under it remain in place.


National Steel Car claimed the FIT program “was actually designed to accomplish social goals unrelated to the generation of electricity,” such as helping rural and indigenous communities, and was therefore a tax trying to help with policy goals.

“The appellant submits that the Policy Goals can be achieved by Ontario in several ways, just not through the electricity pricing formula,” the decision said.

National Steel Car also argued the global adjustment violated a provincial law that requires the government to hold a referendum for new taxes.

“The appellant’s principal claim is that the Global Adjustment was a ‘colourable attempt to disguise a tax as a regulatory charge with the purpose of funding the costs of the Policy Goals,’” the decision said. “The appellant pressed this argument before the motion judge and before this court. The motion judge did not directly or adequately address it.”

The Ontario government applied to have the challenge thrown out for having “no reasonable cause of action,” and a Superior Court judge did so in 2018, saying the global adjustment is not a tax.

National Steel Car appealed the decision, and the decision published Wednesday allowed the appeal, set aside the lower-court judgment, and will send the case back to Superior Court, where it could get a full hearing.

“The appellant’s claim is sufficiently plausible on the evidentiary record it put forward that the applications should not have been dismissed on a pleadings motion before the development of a full record,” wrote Justice Peter D. Lauwers. “It is not plain, obvious and beyond doubt that the Global Adjustment, and particularly the challenged component, is properly characterized as a valid regulatory charge and not as an impermissible tax.”

Jerome Morse of Morse Shannon LLP, one of National Steel Car’s lawyers, said the Ontario government would now have 60 days to decide whether to seek permission to appeal to the Supreme Court of Canada.

“What the court has basically said is, ‘this is a plausible argument, here are the reasons why it’s plausible, there was no answer to this,’” Morse told the Financial Post.

Ontario and the IESO had supported the lower-court decision, but there has been a change in government since the challenge was first launched, with Progressive Conservative Premier Doug Ford replacing the Liberals and Kathleen Wynne in power. The Liberals had launched a plan aimed at addressing hydro costs before losing in a 2018 election, the main thrust of which had been to refinance global adjustment costs.

Wednesday’s decision states that “Ontario’s counsel advised the court that the current Ontario government ‘does not agree with the former government’s electricity procurement policy (since-repealed).’

“The government’s view is that: ‘The solution does not lie with the courts, but instead in the political arena with political actors,’” it adds.

A spokesperson for Ontario Energy Minister Greg Rickford said in an email that they are reviewing the decision but “as this matter is in the appeal period, it would be inappropriate to comment.” 

Ontario had also requested to stay the matter so a regulator, the Ontario Energy Board, could weigh in, while the Nova Scotia regulator approved a 14% hike in a separate case.

“However, Ontario only sought this relief from the motion judge in the alternative, and given the motion judge’s ultimate decision, she did not rule on the stay,” Thursday’s decision said. “It would be premature for this court to rule on the issue, although it seems incongruous for Ontario to argue that the Superior Court is the convenient forum in which to seek to dismiss the applications as meritless, but that it is not the convenient forum for assessing the merits of the applications.”

National Steel Car’s challenge bears a resemblance to the constitutional challenges launched by Ontario and other provinces over the federal government’s carbon tax, but Justice Lauwers wrote “that the federal legislative scheme under consideration in those cases is distinctly different from the legislation at issue in this appeal.”

“Nothing in those decisions impacts this appeal,” the judge added.
 

 

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China boosts wind energy, photovoltaic and concentrated solar power

China Renewable Energy Law drives growth in wind power, solar thermal, and photovoltaic capacity, supporting grid integration and five-year plans, even as China leads CO2 emissions, with policy incentives, compliance inspections, and national resource assessments.

 

Key Points

A legal framework that speeds wind, solar thermal, and PV growth in China via mandates, incentives, and grid rules.

✅ 2018 renewables: 1.87T kWh, 26.7% of national power

✅ Over 100 State Council policies enabling deployment

✅ Law inspections and regional oversight across six provinces

 

China leads renewable energies, installing more wind power, solar thermal and photovoltaic than any other country, as seen in the China solar PV growth reported in 2016, but also leads CO2 emissions, and much remains to be done.

The effective application of Chinas renewable energy law has boosted the use of renewable energy in the country and facilitated the rapid development of the sector, as solar parity across Chinese cities indicates, a report said.

The report on compliance with renewable energy law was presented today at the current bimonthly session of the Standing Committee of the National Peoples Assembly (APN).

Electricity generated by renewable energy amounted to about 1.87 trillion kilowatts per hour in 2018, representing 26.7 percent of Chinas total energy production in the year, aligning with trends where wind and solar doubling globally over five years, the report said.

Ding Zhongli, vice president of the NPC Standing Committee, presented the report to the legislators at the second plenary meeting of the session.

An inspection of the law enforcement was carried out from August to November, as U.S. renewables hit 28% record showed momentum elsewhere. A total of 21 members of the NPC Standing Committee and the NPC Environmental Protection and Resource Conservation Committee, as well as national legislators, traveled to six regions at the provincial level on inspection visits. Twelve legislative bodies at the provincial level inspected the law enforcement efforts in their jurisdictions.

The relevant State Council agencies have implemented more than 100 regulations and policies to foster a good policy environment for the development of renewable energy, as seen in markets where U.S. renewable electricity surpassed coal in 2022. Local regulations have also been formulated based on local conditions, according to the report.

In accordance with the law, a thorough investigation of the national conditions of renewable energy resources was undertaken.

In 2008 and 2014 atlas of solar energy resources and wind energy evaluation of China were issued. The relevant agencies of the State Council have also implemented five-year plans for the development of renewable energy, which have provided guidance to the sector, while countries like Ireland's one-third green power target remain in focus within four years.

The main provisions of the law have been met, the law has been effectively applied and the purpose of the legislation has been met, and this momentum is echoed abroad, with U.S. renewables near one-fourth according to projections, Ding said.

 

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Texas utility companies waiving fees; city has yet to act

Texas Utility COVID-19 Relief suspends disconnections, waives late fees, extends payment plans, and supports broadband access as electric, gas, and internet providers help customers during the statewide emergency with speed upgrades and student WiFi initiatives.

 

Key Points

Texas utilities pause disconnections, waive fees, expand access, and offer flexible payment plans during COVID-19.

✅ Disconnections and late fees suspended by gas, power, internet.

✅ Payment plans and deferred balances after emergency.

✅ Bandwidth caps lifted; student WiFi access for remote learning.

 

In response to the COVID-19 pandemic, Texas utility companies have taken unprecedented steps to keep customers' lights on, gas flowing, and online connections stable -- even if they can't pay, amid concerns over pandemic electricity shutoffs nationwide.

Meantime, Palestine City Council members plan to discuss hardship measures Monday, as some states such as New Jersey and New York implement moratoriums on shut-offs, but have no plans yet to ease the burden of paying two other essential services during the statewide emergency -- trash collection and water. Those services are billed through the city.

For many residents, money will be tight after the statewide emergency declaration. Businesses are cutting back or closing. Workers are staying home to avoid the coronavirus.

"We are putting our customers first," Larry Ball, spokesman for Atmos Energy, a Dallas-based natural gas company, told the Herald-Press Friday. "The safety of all of our customers has always been our first priority."

While the declared emergency remains in effect, Atmos has suspended all late fees and customer disconnections, a step similar to PG&E's shutoff moratorium in California.

"Atmos Energy's commitment to safety, paired with our culture, have led us during unique times," Kevin Akers, Atmos President and CEO said. "This will be no different."

Internet Service Providers SuddenLink and Centurylink have similarly suspended all disconnections and late fees. Additionally, Centurylink, a global company serving 36 states, has promised to scrap bandwidth limits, while ensuring the highest speeds possible.

SuddenLink, a division of Altice Business, is also partnering with school districts in their service area to offer its Student WiFi product free for 60 days. That will allow students who have school-issued devices, but no dedicated home Internet access, the ability to use the Optimum WiFi Hot Spot Network to access their school's network and resources.

Electric companies such as TXU and Houston-based Gexa Energy also are working to keep customers safe and connected, and Entergy's relief fund highlights additional support for customers.

During the declared emergency, Gexa is waiving all disconnection and reconnection fees, as well as late fees, a policy focus that later intersected with debates over a proposed electricity market bailout in Texas. Payment plans will be set up for customers, after the crisis ends, Gexa Energy officials said.

"Everyone needs their power on," a Gexa spokesman said. "That is our number one priority."

TXU, based in Irving, is waiving late fees, extending payment due dates with no down-payment required, and deferring customer balances over multiple installments, while some retailers like Griddy underscored the risks of variable-rate plans.

If customers still can't pay, TXU officials said, the company will keep their lights on, a commitment underscored after the Texas winter storm outages exposed vulnerabilities. Customers in need should call 800-242-9113.

"The coronavirus is causing uncertainty and many hardships," Scott Hudson, president of TXU energy, said. "We are committed to serving our communities."

 

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