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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$1 billion per year is being spent to support climate change denial

Climate Change Consensus and Disinformation highlights the 97% peer-reviewed agreement on human-caused warming, IPCC warnings, and how fossil fuel lobbying, misinformation, and astroturf tactics echo tobacco denial to mislead media and voters.

 

Key Points

Explains the 97% scientific consensus and the disinformation that obscures IPCC findings and misleads the public.

✅ 97% peer-reviewed consensus on human-caused climate change

✅ Fossil fuel funding drives denial and media misinformation

✅ IPCC and major scientific bodies confirm severe impacts

 

Orson Johnson says there is no scientific consensus on climate change. He’s wrong. A 2015 study by Drexel University’s Robert Brulle found that nearly $1 billion per year is being spent to support climate change denial. Electric utilities, fossil fuel and transportation sectors outspent environmental and renewable energy sectors by more than 10-to-1, undermining efforts to achieve net-zero electricity emissions globally. It is virtually the same strategy that tobacco companies used to deny the dangers of tobacco smoke, spending hundreds of millions of dollars to delay recognition of harm from tobacco smoke for decades, and today Trump's oil policies can similarly influence Wall Street's energy strategy. These are the same debunked sources Johnson quotes in his commentary.

The authors of six independent peer-reviewed papers on the consensus for human-caused climate change examined “the available studies and conclude that the finding of 97% consensus in published climate research is robust and consistent with other surveys of climate scientists and peer-reviewed studies,” according to an abstract in Environmental Research Letters, and public support for action is strong, with most Americans willing to contribute financially to climate solutions. Of the 30,000 scientists (people with a bachelor’s degree or higher in science) Johnson cites, only 39 specialized in climate science.

A new study by the U.N. Intergovernmental Panel on Climate Change draws on momentum from the Katowice climate summit to warn that “The consequences for nature and humanity are sweeping and severe.”

California’s Office of Planning and Research says: “Every major scientific organization in the United States with relevant expertise has confirmed the IPCC’s conclusion, including the National Academy of Sciences, the American Meteorological Society, the American Geophysical Union, and the American Association for the Advancement of Science. The list of international scientific organizations affirming the worldwide consensus on climate change is even longer.”

Former President Obama argued that decarbonization is irreversible as the clean-energy transition accelerates.

This issue is a symptom of an even larger problem. Recently, Facebook announced it would continue to allow political ads that contain obvious lies. America’s corporate news media has been following the same policy for years. Printing stories and commentary with information that is clearly not true or where data has been cherry-picked to strongly imply a lie, such as claims that Ottawa is making electricity more expensive for Albertans, sets up a false equivalence fallacy in which two incompatible arguments appear to be logically equivalent when, in fact, they are not.

Conservatives focus exclusively on progressive income taxes to argue that rich people pay a disproportionate share of taxes while ignoring that they take a disproportionate share of income, and federal income taxes account for less than half of taxes collected, with almost all of the other taxes being heavily regressive. Critics of single-payer healthcare disregard that almost every other developed country on earth has been using single-payer for decades to provide better care with universal coverage at roughly half the cost. Other examples abound, including recent policy milestones like the historic U.S. climate deal that nevertheless become targets of misinformation. We live in a society where truth is no longer truth, reality is supplanted by alternative facts and where crippling polarization is driven by the inability to agree on basic facts.

 

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Europe to Weigh Emergency Measures to Limit Electricity Prices

EU Electricity Price Limits are proposed by the European Commission to curb contagion from gas prices, bolster energy security, stabilize the power market, and manage inflation via LNG imports, gas storage, and reduced demand.

 

Key Points

Temporary power-price caps to curb gas contagion, shield consumers, and bolster EU energy security.

✅ Limits decouple electricity from volatile gas benchmarks

✅ Short-term LNG imports and storage to enhance supply security

✅ Market design reforms and demand reduction to tame prices

 

The European Union should consider emergency measures in the coming weeks that could include price cap strategies on electricity prices, European Commission President Ursula von der Leyen told leaders at an EU summit in Versailles.

The reference to the possible measures was contained in a slide deck Ms. von der Leyen used to discuss efforts to curb the EU’s reliance on Russian energy imports, which last year accounted for about 40% of its natural-gas consumption. The slides were posted to Ms. von der Leyen’s Twitter account.

Russia’s invasion of Ukraine has highlighted the vulnerability of Europe’s energy supplies to severe supply disruptions and raised fears that imports could be cut off by Moscow or because of damage to pipelines that run across Ukraine. It has also driven energy prices up sharply, contributing to worries about inflation and economic growth.

Earlier this week, the European Commission, the EU’s executive arm, published the outline of a plan that it said could cut imports of Russian natural gas by two-thirds this year and end the need for those imports entirely before 2030, aligning with calls to ditch fossil fuels in Europe. In the short-term, the plan relies largely on storing natural gas ahead of next winter’s heating season, reducing consumption and boosting imports of liquefied natural gas from other producers.

The Commission acknowledged in its report that high energy prices are rippling through the economy, even as European gas prices have fallen back toward pre-war levels, raising manufacturing costs for energy-intensive businesses and putting pressure on low-income households. It said it would consult “as a matter of urgency” and propose options for dealing with high prices.

The slide deck used by Ms. von der Leyen on Thursday said the Commission plans by the end of March to present emergency options “to limit the contagion effect of gas prices in electricity prices, including temporary price limits, even though rolling back electricity prices can be complex under current market rules.” It also intends this month to set up a task force to prepare for next winter and a proposal for a gas storage policy.

By mid-May, the Commission will set out options to revamp the electricity market and issue a proposal for phasing out EU dependency on Russian fossil fuels by 2027, according to the slides.

French President Emmanuel Macron said Thursday that Europe needs to protect its citizens and companies from the increase in energy prices, adding that some countries, including France, have already taken some national measures.

“If this lasts, we will need to have a more long-lasting European mechanism,” he said. “We will give a mandate to the Commission so that by the end of the month we can get all the necessary legislation ready.”

The problem with price limits is that they reduce the incentive for people and businesses to consume less, said Daniel Gros, distinguished fellow at the Centre for European Policy Studies, a Brussels think tank. He said low-income families and perhaps some businesses will need help dealing with high prices, but that should come as a lump-sum payment that isn’t tied to how much energy they are consuming.

“The key will be to let the price signal work,” Mr. Gros said in a paper published this week, which argued that high energy prices could result in lower demand in Europe and Asia, reducing the need for Russian natural gas. “Energy must be expensive so that people save energy,” he said.

Ms. von der Leyen’s slides suggest the EU hopes to replace 60 billion cubic meters of Russian gas with alternative suppliers, including suppliers of liquefied natural gas, by the end of this year. Another 27 billion cubic meters could be replaced through a combination of hydrogen and EU production of biomethane, according to the slide deck.

 

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Duke Energy Florida's smart-thinking grid improves response, power restoration for customers during Hurricane Ian

Self-healing grid technology automatically reroutes power to reduce outages, speed restoration, and boost reliability during storms like Hurricane Ian in Florida, leveraging smart grid sensors, automation, and grid hardening to support Duke Energy customers.

 

Key Points

Automated smart grid systems that detect faults and reroute power to minimize outages and accelerate restoration.

✅ Cuts outage duration via automated fault isolation

✅ Reroutes electricity with sensors and distribution automation

✅ Supports storm resilience and faster field crew restoration

 

As Hurricane Ian made its way across Florida, where restoring power in Florida can take weeks in hard-hit areas, Duke Energy's grid improvements were already on the job helping to combat power outages from the storm.

Smart, self-healing technology, similar to smart grid improvements elsewhere, helped to automatically restore more than 160,000 customer outages and saved nearly 3.3 million hours (nearly 200 million minutes) of total lost outage time.

"Hurricane Ian is a strong reminder of the importance of grid hardening and storm preparedness to help keep the lights on for our customers," said Melissa Seixas, Duke Energy Florida state president. "Self-healing technology is just one of many grid improvements that Duke Energy is making to avoid outages, restore service faster and increase reliability for our customers."

Much like the GPS in your car can identify an accident ahead and reroute you around the incident to keep you on your way, self-healing technology is like a GPS for the grid. The technology can quickly identify power outages and alternate energy pathways to restore service faster for customers when an outage occurs.

Additionally, self-healing technology provides a smart tool to assist crews in the field with power restoration after a major storm like Ian, helping reduce outage impacts and freeing up resources to help restore power in other locations.

Three days after Hurricane Ian exited the state, Duke Energy Florida wrapped up restoration of approximately 1 million customers. This progress enabled the company to deploy more than 550 Duke Energy workers from throughout Florida, as well as contractors from across the country, to help restore power for Lee County Electric Cooperative customers.

Crews worked in Cape Coral and Pine Island, one of the hardest-hit areas in the storm's path, as Canadian power crews have in past storms, and completed power restoration for the majority of customers on Pine Island within approximately one week after arriving to the island.

Prior to Ian in 2022, smart, self-healing technology had helped avoid nearly 250,000 extended customer outages in Florida, similar to Hydro One storm recovery efforts, saving around 285,000 hours (17.1 million minutes) of total lost outage time.

Duke Energy currently serves around 59% of customers in Florida with self-healing capabilities on its main power distribution lines, with a goal of serving around 80% over the next few years.

 

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Manitoba Hydro scales back rate increase next year

Manitoba Hydro 3.5 Percent Rate Increase proposes a smaller electricity rate hike under Public Utilities Board oversight to bolster financial reserves, address debt and Bipole III costs, amid shifting export sales and water flow conditions.

 

Key Points

It is Manitoba Hydro's proposed 3.5% electricity rate hike for 2019-20 to shore up finances under PUB oversight.

✅ PUB review sought without lengthy hearing

✅ Revenue boost forecast at 59 million dollars

✅ Natural gas rates flat; class shifts adjust bills

 

Manitoba Hydro is scaling back its rate hike request for next year, instead of the annual 7.9 per cent hikes the Crown corporation previously said it would need until 2023-24 to address debt. 

Hydro is asking the Public Utilities Board for a 3.5 per cent rate increase next year, which would take effect on April 1.

In last week's application, Hydro said its new board is reviewing the corporation's financial picture. Once that is complete, the utility expects to submit a new multi-year rate plan in late 2019 that addresses the organization's long-term future.

"It's too speculative at this point to discuss any possible future rate increases," spokesperson Bruce Owen said in an email.

The proposed increase next year is similar to other jurisdictions and nearly in line with the Public Utilities Board's decision to allow an average 3.6 per cent jump in electricity rates in 2018-19, which began this summer.

"The requested 3.5 per cent rate increase … generates a modest level of net income under average water flow conditions that will assist in gradually building the revenue base and reduce the risk of the corporation incurring a loss" in 2019-20, the rate application said.

If approved, consumers would face their second rate increase from Hydro in under a year.

Crown Services Minister Colleen Mayer said she's sympathetic to customers bracing for another rate increase amid NL rate hike concerns that far exceeds the rate of inflation.

"I hear that, very clearly," she said. "The NDP left us with an insurmountable problem — we're trying to fix that."

Hydro goes to court over special rate class for First Nations residents in Manitoba

National Energy Board OK's Manitoba-Minnesota Transmission Project

Next year's rate increase is projected to bring in $59 million of revenue, boosting the Crown corporation's financial reserves by $31 million.

Without it, the utility would deal with a net loss, it said.

This time, Hydro officials are asking PUB to forgo a rate hearing, suggesting neither itself nor the board has the resources for a lengthy six- to nine-month process to review an application where not much has changed financially and would generate a "minimum level of net income," Hydro said in a letter to the board.

The short-term rate relief, the letter recommends, should be "awarded in a timely and cost-effective manner, recognizing that the corporation's long-term financial forecasts will be finalized and available for review" in late 2019.

Hydro's net income next year will be lower than projected, the rate application said, due to a reduction in export sales and increases in depreciation and financing costs from Bipole III.

"Even though they had a total implosion of their previous board, on this very issue, they haven't learned lessons and they continue to be cheerleaders for these rapid rate increases," Kinew said, referring to the exodus of every board member but one earlier this year.

Manitoba Hydro's burgeoning debt surpasses $19 billion

On natural gas, Manitoba Hydro is asking PUB for no rate increase for the next two years.

There will, however, be some changes in rates in different customer classes, Owen said, resulting in modest rate reductions for mainly residential customers and increases for customers who use a lot of natural gas.

The corporation also wants to stop collecting fees to support the furnace replacement program. The initiative will continue with existing fees.

 

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FERC needs to review capacity market performance, GAO recommends

FERC Capacity Markets face scrutiny as GAO flags inconsistent data on resource adequacy and costs, urging performance goals, risk assessment, and better metrics across PJM, ISO-NE, NYISO, and MISO amid cost-recovery proposals.

 

Key Points

FERC capacity markets aim for resource adequacy, but GAO finds weak data and urges goals and performance reviews.

✅ GAO cites inconsistent data on resource adequacy and costs

✅ Calls for performance goals, metrics, and risk assessment

✅ Applies to PJM, ISO-NE, NYISO; MISO market is voluntary

 

Capacity markets may or may not be functioning properly, but FERC can't adequately make that determination, according to the GAO report.

"Available information on the level of resource adequacy ... and related costs in regions with and without capacity markets is not comprehensive or consistent," the report found. "Moreover, consistent data on historical trends in resource adequacy and related costs are not available for regions without capacity markets."

The review concluded that FERC collects some useful information in regions with and without capacity markets, but GAO said it "identified problems with data quality, such as inconsistent data."

GAO included three recommendations, including calling for FERC to take steps to improve the quality of data collected, and regularly assess the overall performance of capacity markets by developing goals for those assessments.

"FERC should develop and document an approach to regularly identify, assess, and respond to risks that capacity markets face," the report also recommended. The commission "has not established performance goals for capacity markets, measured progress against those goals, or used performance information to make changes to capacity markets as needed."

The recommendation comes as the agency is grappling with a controversial proposal to assure cost-recovery for struggling coal and nuclear plants in the power markets. So far, the proposal would only apply to power markets with capacity markets, including PJM Interconnection, the New England ISO, the New York ISO and possibly MISO. However MISO only has a voluntary capacity market, making it unclear how the proposed rule would be applied there. 

 

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Brand New Renewable Technology Harnesses Electricity From The Cold, Dark Night

Nighttime Thermoelectric Generator converts radiative cooling into renewable energy, leveraging outer space cold; a Stanford-UCLA prototype complements solar, serving off-grid loads with low-power output during peak evening demand, using simple materials on a rooftop.

 

Key Points

A device converting nighttime radiative cooling into electricity, complementing solar for low-power evening needs.

✅ Uses thermocouples to convert temperature gradients to voltage.

✅ Exploits radiative cooling to outer space for night power.

✅ Complements solar; low-cost parts suit off-grid applications.

 

Two years ago, one freezing December night on a California rooftop, a tiny light shone weakly with a little help from the freezing night air. It wasn't a very bright glow. But it was enough to demonstrate the possibility of generating renewable power after the Sun goes down.

Working with Stanford University engineers Wei Li and Shanhui Fan, University of California Los Angeles materials scientist Aaswath Raman put together a device that produces a voltage by channelling the day's residual warmth into cooling air, effectively generating electricity from thin air with passive heat exchange.

"Our work highlights the many remaining opportunities for energy by taking advantage of the cold of outer space as a renewable energy resource," says Raman.

"We think this forms the basis of a complementary technology to solar. While the power output will always be substantially lower, it can operate at hours when solar cells cannot."

For all the merits of solar energy, it's just not a 24-7 source of power, although research into nighttime solar cells suggests new possibilities for after-dark generation. Sure, we can store it in a giant battery or use it to pump water up into a reservoir for later, but until we have more economical solutions, nighttime is going to be a quiet time for renewable solar power. 

Most of us return home from work as the Sun is setting, and that's when energy demands spike to meet our needs for heating, cooking, entertaining, and lighting.

Unfortunately, we often turn to fossil fuels to make up the shortfall. For those living off the grid, it could require limiting options and going without a few luxuries.

Shanhui Fan understands the need for a night time renewable power source well. He's worked on a number of similar devices, including carbon nanotube generators that scavenge ambient energy, and a recent piece of technology that flipped photovoltaics on its head by squeezing electricity from the glow of heat radiating out of the planet's Sun-warmed surface.

While that clever item relied on the optical qualities of a warm object, this alternative device makes use of the good old thermoelectric effect, similar to thin-film waste-heat harvesting approaches now explored.

Using a material called a thermocouple, engineers can convert a change in temperature into a difference in voltage, effectively turning thermal energy into electricity with a measurable voltage. This demands something relatively toasty on one side and a place for that heat energy to escape to on the other.

The theory is the easy part – the real challenge is in arranging the right thermoelectric materials in such a way that they'll generate a voltage from our cooling surrounds that makes it worthwhile.

To keep costs down, the team used simple, off-the-shelf items that pretty much any of us could easily get our hands on.

They put together a cheap thermoelectric generator and linked it with a black aluminium disk to shed heat in the night air as it faced the sky. The generator was placed inside a polystyrene enclosure sealed with a window transparent to infrared light, and linked to a single tiny LED.


 

For six hours one evening, the box was left to cool on a roof-top in Stanford as the temperature fell just below freezing. As the heat flowed from the ground into the sky, the small generator produced just enough current to make the light flicker to life.

At its best, the device generated around 0.8 milliwatts of power, corresponding to 25 milliwatts of power per square metre.

That might just be enough to keep a hearing aid working. String several together and you might just be able to keep your cat amused with a simple laser pointer. So we're not talking massive amounts of power.

But as far as prototypes go, it's a fantastic starting point. The team suggests that with the right tweaks and the right conditions, 500 milliwatts per square metre isn't out of the question.

"Beyond lighting, we believe this could be a broadly enabling approach to power generation suitable for remote locations, and anywhere where power generation at night is needed," says Raman.

While we search for big, bright ideas to drive the revolution for renewables, it's important to make sure we don't let the smaller, simpler solutions like these slip away quietly into the night.

This research was published in Joule.

 

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