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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Alberta Ends Moratorium on Renewable Energy Projects

Alberta Ends Renewable Energy Moratorium, accelerating wind and solar deployment while prioritizing grid stability, reliability, and infrastructure upgrades to attract investment, cut emissions, meet climate targets, and integrate renewables into the provincial power system.

 

Key Points

It is Alberta's decision to lift a pause on new wind and solar projects while enhancing grid reliability.

✅ Resumes wind and solar development across Alberta.

✅ Focuses on grid stability and infrastructure upgrades.

✅ Aims to attract investment and meet climate targets.

 

The Alberta government has announced the end of a temporary suspension on the development of new renewable energy projects, as the power grid operator prepares to accept green energy bids across the market. This pause, which had been in place since May 2023, was initially implemented to evaluate the effects of rapid growth in renewable energy installations on the province's power grid and overall energy system. However, the decision to lift the moratorium reflects a shift in the government’s approach to balancing energy needs and environmental goals.

The suspension was introduced amid concerns that the swift expansion of wind and solar energy projects, including documented challenges with solar energy expansion in the province, could place undue stress on Alberta's electrical grid and infrastructure. Officials expressed worries about the ability of the grid to handle the increased load and the potential need for upgrades to accommodate new renewable energy sources. The government aimed to assess the implications of this growth and determine appropriate measures to ensure that the energy system could support both existing and future demands.

The moratorium drew significant criticism from various sectors, including renewable energy companies, environmental advocates, and local communities. Critics argued that the pause was detrimental to Alberta's efforts to transition to cleaner energy sources and meet climate targets, citing cases like TransAlta scrapping a wind farm amid policy uncertainty. They pointed out that halting projects could delay investments and job creation associated with the renewable energy sector, potentially impeding progress towards a more sustainable energy future.

In response to these concerns, the Alberta government conducted further reviews and consultations. The decision to cancel the pause reflects the government’s recognition of the importance of advancing renewable energy initiatives while also addressing the need for grid stability and infrastructure development. By ending the moratorium, the government aims to support the continued growth of renewable energy projects and maintain momentum in the shift towards greener energy solutions.

The lifting of the moratorium is expected to have a positive impact on the renewable energy industry in Alberta. Several planned projects that were put on hold can now proceed, leading to renewed investment and economic benefits, including a renewable energy surge that could power 4,500 jobs across the province. The government’s decision signals a commitment to integrating renewable energy sources into the provincial grid in a way that ensures both reliability and sustainability.

Going forward, the Alberta government plans to implement measures to better manage the integration of renewable energy into the existing power infrastructure. This includes addressing any potential challenges related to grid capacity and ensuring that the growth of renewable energy projects aligns with the province's overall energy strategy, as recent federal procurement such as a $500M green electricity contract with an Edmonton company underscores demand that integration efforts must accommodate. The goal is to create a balanced approach that supports the development of clean energy while maintaining the stability and efficiency of the energy system.

The end of the moratorium aligns with Alberta’s broader objectives to reduce greenhouse gas emissions and promote environmental sustainability within a province recognized as a powerhouse for both green energy and fossil fuels in Canada. The government’s approach reflects a willingness to adapt policies and strategies in response to evolving industry needs and environmental priorities. By removing the pause, Alberta demonstrates its commitment to fostering a diverse and resilient energy sector that can meet both current and future demands.

The decision to cancel the moratorium is also seen as a move to reinforce Alberta’s position as a leader in renewable energy development. With the lifting of restrictions, the province can continue to attract investment in clean energy projects, as neighboring jurisdictions such as B.C. streamline clean energy approvals to accelerate deployment, enhance its reputation as a progressive energy market, and contribute to global efforts to address climate change.

In summary, the Alberta government’s decision to lift the pause on renewable energy projects represents a significant shift in its approach to energy policy. The move reflects an acknowledgment of the importance of advancing renewable energy while addressing the practical challenges associated with grid management and infrastructure development. By ending the moratorium, Alberta aims to support the growth of clean energy initiatives and maintain its commitment to sustainability and environmental responsibility.

 

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Electric vehicle sales triple in Australia despite lack of government support

Australian Electric Vehicle Sales tripled in 2019 amid expanding charging infrastructure and more models, but market share remains low, constrained by limited government policy, weak incentives, and absent emissions standards despite growing ultra-fast chargers.

 

Key Points

EV units sold in Australia; in 2019 they tripled to 6,718, but market share was just 0.6%.

✅ Sales rose from 2,216 (2018) to 6,718 (2019); ~80% were BEVs.

✅ Public charging sites reached 2,307; fast chargers up 40% year-on-year.

✅ Policy gaps and absent standards limit model supply and EV uptake.

 

Sales of electric vehicles in Australia tripled in 2019 despite a lack of government support, according to the industry’s peak body.

The country’s network of EV charging stations was also growing, the Electric Vehicle Council’s annual report found, including a rise in the number of faster charging stations that let drivers recharge a car in about 15 minutes.

But the report, released on Wednesday, found the market share for electric vehicles was still only 0.6% of new vehicle sales – well behind the 2.5% to 5% in other developed countries.

The chief executive of the council, Behyad Jafari, said the rise in sales was down to more models becoming available. There are now 28 electric models on sale, with eight priced below $65,000.

Six more were due to arrive before the end of 2021, including two priced below $50,000, the council’s report said.

“We have repeatedly heard from car companies that they were planning to bring vehicles here, but Australia doesn’t have that policy support.”

The Morrison government promised a national electric vehicle strategy would be finalised by the middle of this year, but the policy has been delayed. The prime minister, Scott Morrison, last year accused Labor of wanting to “end the weekend” and force people out of four-wheel drives after the opposition set a target of 50% of new car sales being electric by 2030.

Jafari cited the Kia e-Niro – an award-winning electric SUV that was being prepared for an Australian launch, but is now reportedly on hold because the manufacturer favoured shipping to countries with emissions standards.

The council’s members include BMW, Nissan, Hyundai and Harley Davidson, as well as energy, technology and charging infrastructure companies.

Sales of electric vehicles – which include plug-in hybrids – went from 2,216 in 2018 to 6,718 in 2019, the report said. Jafari said about 80% of those sales were all-electric vehicles.

There have been 3,226 electric vehicles sold in 2020, the report said, despite an overall drop of 20% in vehicle sales due to the Covid-19 pandemic, while U.S. EV sales have surged into 2024.

Jafari said: “Our report is showing that Australian consumers want these cars.

“There is no controversy that the future of the industry is electric, but at the moment the industry is looking at different markets. We want policies that show [Australia] is going on this journey.”

Government agency data has forecast that half the new cars sold will be electric by 2035, underscoring that the age of electric cars is arriving even if there is no policy to support their uptake.

Manufacturers currently selling electric cars in Australia are Nissan, Hyundai, Mitsubishi, Tesla, Volvo, Porsche, Audi, BMW, Mercedes, Jaguar and Renault, the report said.

Jafari said most G20 countries had emissions standards in place for vehicles sold and incentives in place to support electric vehicles, such as rebates or exemptions from charges. This hadn’t happened in Australia, he said.

The report said: “Globally, carmakers are rolling out more electric vehicle models as the electric car market expands, but so far production cannot keep up with demand. This means that without policy signals, Australians will continue to be denied access to the full global range of electric vehicles.”

On Tuesday, one Australian charging provider, Evie Networks, opened an ultra-fast station at a rest stop at Campbell Town in Tasmania – between Launceston and Hobart.

The company said the station would connect EV owners in the state’s north and south and the two 350kW chargers could recharge a vehicle in 15 minutes, highlighting whether grids have the power to charge EVs at scale. Two more sites were planned for Tasmania, the company said.

A Tasmanian government grant to support electric vehicle charging had helped finance the site. Evie was also supported with a $15m grant from the federal government’s Australian Renewable Energy Agency.

According to the council report, Australia now has 2,307 public charging stations, including 357 fast chargers – a rise of 40% in the past year.

A survey of 2,900 people in New South Wales, the ACT, Victoria and South Australia, carried out by NRMA, RACV and RAA on behalf of the council, found the main barriers to buying an electric vehicle were concerns over access to charging points, higher prices and uncertainty over driving range.

Consumers favoured electric vehicles because of their environmental footprint, lower maintenance costs and vehicle performance.

The report said the average battery range of electric vehicles available in Australia was 400km, but almost 80% of people thought the average was less.

According to the survey, 56% of Australians would consider an electric car when they next bought a vehicle, and in the UK, EV inquiries soared during a fuel supply crisis.

“We are far behind, but it is surmountable,” Jafari said.

The council report also rated state and territories on the policies that supported its industry and found the ACT was leading, followed by NSW and Queensland.

A review of commercial electric vehicle use found public electric bus trials were planned or under way in Queensland, NSW, WA, Victoria and ACT. There are now more than 400,000 electric buses in use around the globe.

 

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Europe's Thirst for Electricity Spurs Nordic Grid Blockade

Nordic Power Grid Dispute highlights cross-border interconnector congestion, curtailed exports and imports, hydropower priorities, winter demand spikes, rising spot prices, and transmission grid security amid decarbonization efforts across Sweden, Norway, Finland, and Denmark.

 

Key Points

A clash over interconnectors and capacity cuts reshaping trade, prices, and reliability in the Nordic power market.

✅ Sweden cuts interconnector capacity to protect grid stability

✅ Norway prioritizes higher-priced exports via new cables

✅ Finland and Denmark seek EU action on capacity curtailments

 

A spat over electricity supplies is heating up in northern Europe. Sweden is blocking Norway from using its grids to transfer power from producers throughout the region. That’s angered Norway, which in turn has cut flows to its Nordic neighbor.

The dispute has built up around the use of cross-border power cables, which are a key part of Europe’s plans to decarbonize since they give adjacent countries access to low-carbon resources such as wind or hydropower. The electricity flows to wherever prices are higher, informed by how electricity is priced across Europe, without interference from grid operators -- but in the event of a supply squeeze, flows can be stopped.

Sweden moved to safeguard the security of its grid after Norway started increasing electricity exports through huge new cables to Germany and the U.K. Those exports at times have drawn energy away from Sweden, resulting in the country’s system operator cutting capacity at its Nordic borders, preventing exports but also hindering imports, which it relies on to handle demand spikes during winter.

“This is not a good situation in the long run,” Christian Holtz, a energy market consultant for Merlin & Metis AB.

Norway hit back last week by cutting flows to Sweden, this will prioritize better paying customers in Europe, amid Irish price spikes that highlight dispatchable shortages, giving them access to its vast hydro resources at the expense of its Nordic neighbors. 

By partially closing its borders Sweden can’t access imports either, which it relies on to handle demand spikes during the coldest days of the winter. 

In Denmark, unusual summer and autumn winds have at times delivered extraordinarily low electricity prices that ripple through regional markets.

The Swedish grid manager Svenska Kraftnat has reduced export capacity at cables across its borders by as much as half this year to keep operations secure. Finland and Denmark rely on imports too and the cuts will come at a cost for millions of homes and industries across the four nations already contending with record electricity rates this year. 

Finland and Denmark want the European Union to end the exemption to regulations that make such reductions possible in the first place, as Europe is losing nuclear power and facing tighter supply.

“Imports from our neighboring countries ensure adequacy at times of peak consumption,” said Reima Paivinen, head of operation at the Finland’s Fingrid. “The recent surge in electricity prices throughout Europe does not directly affect the adequacy of electricity, but prices may rise dramatically for short periods.”

Svenska Kraftnat says it’s not political -- it has no choice but to cut capacity until its old grids are expanded to handle the new direction of flows, a challenge mirrored by grid expansion woes in Germany that slow integration. That could take at least until 2030 to complete, it said earlier this year. At the same time, Norway halving available export capacity to about 1,200 megawatts will increase risk of shortages. 

“If we need more we will have to count on imports from other countries,” said Erik Ek, head of strategic operation at Svenska Kraftnat. “If that is not available, we will have to disconnect users the day it gets cold.”

 

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Coal demand dropped in Europe over winter despite energy crisis

EU Winter Energy Mix 2022-2023 shows renewables, wind, solar, and hydro overtaking coal and gas, as demand fell amid high prices; Ember and IEA confirm lower emissions across Europe during the energy crisis.

 

Key Points

It describes Europe's winter power mix: reduced coal and gas, and record wind, solar, and hydro output.

✅ Coal generation fell 11% YoY; gas output declined even more.

✅ Renewables supplied 40%: wind, solar, and hydro outpaced fossil fuels.

✅ Ember and IEA confirm trends; mild winter tempered demand.

 

The EU burned less coal this winter during the energy crisis than in previous years, according to an analysis, quashing fears that consumption of the most polluting fossil fuel would soar as countries scrambled to find substitutes for lost supplies of Russian gas.

The study from energy think-tank Ember shows that between October 2022 and March 2023 coal generation fell 27 terawatt hours, or almost 11 per cent year on year, while gas generation fell 38 terawatt hours, as renewables crowded out gas and consumers cut electricity consumption in response to soaring prices.

Renewable energy supplies also rose, with combined wind and solar power and hydroelectric output outstripping fossil fuel generation for the first time, providing 40 per cent of all electricity supplies. The Financial Times checked Ember’s findings with the International Energy Agency, which said they broadly matched its own preliminary analysis of Europe’s electricity generation over the winter.

The study demonstrates that fears of a steep rebound in coal usage in Europe’s power mix were overstated, despite the continent’s worst energy crisis in 40 years following Russia’s full-scale invasion of Ukraine, even as stunted hydro and nuclear output in parts of Europe posed challenges.

While Russia slashed gas supplies to Europe and succeeded in boosting energy prices for consumers to record levels, the push by governments to rejuvenate old coal plants, including Germany's coal generation, to ensure the lights stayed on ultimately did not lead to increased consumption.

“With Europe successfully on the other side of this winter and major supply disruptions avoided, it is clear the threatened coal comeback did not materialise,” analysts at Ember said in the report.

“With fossil fuel generation down, EU power sector emissions during winter were the lowest they have ever been.”

Ember cautioned, however, that Europe had been assisted by a mild winter that helped cut electricity demand for heating and there was no guarantee of such weather next winter. Companies and households had also endured a lot of pain as a result of the higher prices that had led them to cut consumption, even though in some periods, such as the latest lockdown, power demand held firm in parts of Europe.

Total electricity consumption between October and March declined 94 terawatt hours, or 7 per cent, compared with the same period in winter 2021/22, continuing post-Covid transition dynamics across Europe.

“For a lot of people this winter was really hard with electricity prices that were extraordinarily high and we shouldn’t lose sight of that,” said Ember analyst Harriet Fox.

 

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Coronavirus impacts dismantling of Germany's Philippsburg nuclear plant

Philippsburg Demolition Delay: EnBW postpones controlled cooling-tower blasts amid the coronavirus pandemic, affecting decommissioning timelines in Baden-Wurttemberg and grid expansion for a transformer station to route renewable power and secure supply in southern Germany.

 

Key Points

EnBW's COVID-19 delay of Philippsburg cooling-tower blasts, affecting decommissioning and grid plans.

✅ Controlled detonation shifted to mid-May at earliest

✅ Demolition links to transformer station for north-south grid

✅ Supports security of supply in southern Germany

 

German energy company EnBW said the coronavirus outbreak has impacted plans to dismantle its Philippsburg nuclear power plant in Baden-Wurttemberg, southwest Germany, amid plans to phase out coal and nuclear nationally.

The controlled detonation of Phillipsburg's cooling towers will now take place in mid-May at the earliest, subject to coordination as Germany debates whether to reconsider its nuclear phaseout in light of supply needs.

However, EnBW said the exact demolition date depends on many factors - including the further development in the coronavirus pandemic and ongoing climate policy debates about energy choices.

Philippsburg 2, a 1402MWe pressurised water reactor unit permanently shut down on 31 December 2019, as part of Germany's broader effort to shut down its remaining reactors over time.

At the end of 2019, the Ministry of the Environment gave basic approval for decommissioning and dismantling of unit 2 of the Philippsburg nuclear power plant, inluding explosive demolition of the colling towers. Since then EnBW has worked intensively on getting all the necessary formal steps on the way and performing technical and logistical preparatory work, even as discussions about a potential nuclear resurgence continue nationwide.

“The demolition of the cooling towers is directly related to future security of supply in southern Germany. We therefore feel obliged to drive this project forward," said Jörg Michels head of the EnBW nuclear power division.

The timely removal of the cooling towers is important as the area currently occupied by nuclear plant components is needed for a transformer station for long-distance power lines, an issue underscored during the energy crisis when Germany temporarily extended nuclear power to bolster supply. These will transport electricity from renewable sources in the north to industrial centres in the south.

As of early 2020, there six nuclear reactors in operation in Germany, even as the country turned its back on nuclear in subsequent years. According to research institute Fraunhofer ISE, nuclear power provided about 14% of Germany's net electricity in 2019, less than half of the figure for 2000.

 

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More Polar Vortex 2021 Fallout (and Texas Two-Step): Monitor For ERCOT Identifies Improper Payments For Ancillary Services

ERCOT Ancillary Services Clawback and VOLL Pricing summarize PUCT and IMM actions on load shed, real-time pricing adders, clawbacks, and settlement corrections after the 2021 winter storm in the Texas power grid market.

 

Key Points

Policies addressing clawbacks for unprovided AS and correcting VOLL-based price adders after load shed ended in ERCOT.

✅ PUCT ordered clawbacks for ancillary services not delivered.

✅ IMM urged price correction after firm load shed ceased.

✅ ERCOT's VOLL adder raised costs by $16B during 32 hours.

 

Potomac Economics, the Independent Market Monitor (IMM) for the Electric Reliability Council of Texas (ERCOT), filed a report with the Public Utility Commission of Texas (PUCT) that certain payments were made by ERCOT for Ancillary Services (AS) that were not provided, even as ERCOT later issued a winter reliability RFP to procure capacity during subsequent seasons.

According to the IMM (emphasis added):

There were a number of instances during the operating days outlined above in which AS was not provided in real time because of forced outages or derations. For market participants that are not able to meet their AS responsibility, typically the ERCOT operator marks the short amount in the software. This causes the AS responsibility to be effectively removed and the day-ahead AS payment to be clawed back in settlement. However, the ERCOT operators did not complete this task during the winter event, echoing issues like the Ontario IESO phantom demand that cost customers millions, and therefore the "failure to provide" settlements were not invoked in real time.

Removing the operator intervention step and automating the "failure to provide" settlement was contemplated in NPRR947: Clarification to Ancillary Service Supply Responsibility Definition and Improvements to Determining and Charging for Ancillary Service Failed Quantities; however, the NPRR was withdrawn in August 2020 amid ongoing market reform discussions because of the system cost, some complexities related to AS trades, and the implementation of real-time co-optimization.

Invoking the "failure to provide" settlement for all AS that market participants failed to provide during the operating days outlined above will produce market outcomes and settlements consistent with underlying market principles. In this case, the principle is that market participants should not be paid for services that they do not provide, even as a separate ruling found power plants exempt from providing electricity in emergencies under Texas law, underscoring the distinction between obligations and settlements. Whether ERCOT marked the short amount in real-time or not should not affect the settlement of these ancillary services.

On March 3, 2021, the PUCT ordered (a related press release is here) that:

ERCOT shall claw back all payments for ancillary service that were made to an entity that did not provide its required ancillary service during real time on ERCOT operating days starting February 14, 2021 and ending on February 19,2021.

On March 4, 2021, the IMM filed another report and recommended that:

the [PUCT] direct ERCOT to correct the real-time prices from 0:00 February 18,2021, to 09:00 February 19, 2021, to remove the inappropriate pricing intervention that occurred during that time period.

The IMM approvingly noted the PUCT's February 15, 2021 order, which mandated that real-time energy prices reflect firm load shed by setting prices at the value of lost load (VOLL).1

According to the IMM (emphasis added):

This is essential in an energy-only market, like ERCOT's, where the Texas power grid faces recurring crisis risks, because it provides efficient economic signals to increase the electric generation needed to restore the load and service it reliably over the long term.

Conversely, it is equally important that prices not reflect VOLL when the system is not in shortage and load is being served, and experiences in capacity markets show auction payouts can fall sharply under different conditions. The Commission recognized this principle in its Order, expressly stating it is only ERCOT's out-of-market shedding firm load that is required to be reflected in prices. Unfortunately, ERCOT exceeded the mandate of the Commission by continuing to set process at VOLL long after it ceased the firm load shed.

ERCOT recalled the last of the firm load shed instructions at 23:55 on February 17, 2021. Therefore, in order to comply with the Commission Order, the pricing intervention that raised prices to VOLL should have ended immediately at that time. However, ERCOT continued to hold prices at VOLL by inflating the Real-Time On-Line Reliability Deployment Price Adder for an additional 32 hours through the morning of February 19. This decision resulted in $16 billion in additional costs to ERCOT's market, prompting legislative bailout proposals in Austin, of which roughly $1.5 billion was uplifted to load-serving entities to provide make-whole payments to generators for energy that was not needed or produced.

However, at its March 5, 2021, open meeting (related discussion begins around minute 20), although the PUCT acknowledged the "good points" raised by the IMM, the PUCT was not willing to retrospectively adjust its real-time pricing for this period out of concerns that some related transactions (ICE futures and others) may have already settled and for unintended consequences of such retroactive adjustments.  

 

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