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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Iraq plans nuclear power plants to tackle electricity shortage

Iraq Nuclear Power Plan targets eight reactors and 11 GW to ease blackouts, curb emissions, and support desalination, with financing via partners like Rosatom and Kepco amid OPEC-linked demand growth and chronic grid shortages.

 

Key Points

A $40B push to build eight reactors adding 11 GW, easing blackouts, cutting emissions, and supporting desalination.

✅ $40B, 20-year payback via partner financing

✅ Talks with Rosatom, Kepco; U.S. and France consulted

✅ Parallel solar buildout to meet 2030 demand

 

Iraq is working on a plan to build nuclear reactors as the electricity-starved petrostate seeks to end the widespread blackouts that have sparked social unrest.

OPEC’s No. 2 oil producer – already suffering from power shortages and insufficient investment in aging plants – needs to meet an expected 50% jump in demand by the end of the decade. Building atomic plants could help to close the supply gap, though the country will face significant financial and geopolitical challenges in bringing its plan to fruition.

Iraq seeks to build eight reactors capable of producing about 11 gigawatts, said Kamal Hussain Latif, chairman of the Iraqi Radioactive Sources Regulatory Authority. It would seek funding from prospective partners for the $40 billion plan and pay back the costs over 20 years, he said, adding that the authority had discussed cooperation with Russian and South Korean officials, as Iran-Iraq energy cooperation progresses across the sector.

Plunging crude prices last year deprived Iraq of funds to maintain and expand its long-neglected electricity system, though grid rehabilitation deals have been finalized to support upgrades. The resulting outages triggered protests that threatened to topple the government.

“We have several forecasts that show that without nuclear power by 2030, we will be in big trouble,” Latif said in an interview at his office in Baghdad. Not only is there the power shortage and surge in demand to deal with, but Iraq is also trying to cut emissions and produce more water via desalination — “issues that raise the alarm for me.”

Raising financing will be a major task given that Iraq has suffered budgetary crises amid volatile oil prices. Even with crude at about $70 a barrel now, the country is only just balancing its budget, according to data from the International Monetary Fund.

The government will also have to tackle geopolitical concerns around the safety of atomic energy, which have stymied nuclear ambitions elsewhere in the region, even as Europe's nuclear decline underscores broader energy challenges.

Nuclear power, which doesn’t produce carbon dioxide, would help Gulf states’ efforts to cut emissions as governments worldwide, including India's nuclear push to expand capacity, look to become greener. The technology would also allow them to earmark more of their valuable hydrocarbons for export. Saudi Arabia, which is building a test reactor, burns as much as 1 million barrels of crude a day in power plants during its summer months when temperatures soar beyond 50 degrees Celsius (122 Fahrenheit).

The Iraqi cabinet is reviewing an agreement with Russia’s Rosatom Corp. to cooperate in building reactors, Latif said. South Korean officials this year said they wanted to help build the plants and offered the Iraqis a tour of UAE nuclear reactors run by Korea Electric Power Corp. Latif said the nuclear authority has also spoken with French and U.S. officials about the plan.

Kepco, Rosatom
Kepco, as the Korean energy producer is known, is not aware of Iraq’s nuclear plans and hasn’t been in touch with Iraqi officials or been asked to work on any projects there, a company spokesman said Tuesday. Rosatom didn’t immediately comment when asked about an agreement with Iraq.

Even if Iraq builds the planned number of power stations, that still won’t be sufficient to cover future consumption. The country already faces a 10-gigawatt gap between capacity and demand and expects to need an additional 14 gigawatts this decade, Latif said.

With this in mind, Iraq plans to build enough solar plants to generate a similar amount of power to the nuclear program by the end of the decade.
Iraq currently boasts 18.4 gigawatts of electricity, including 1.2 gigawatts imported from Iran into the grid. Capacity additions mean generation will rise to as much as 22 gigawatts by August, but that’s well short of notional demand that stands at almost 28 gigawatts under normal conditions. Peak usage during the hot summer months of July and August exceeds 30 gigawatts, according to the Electricity Ministry. Demand will hit 42 gigawatts by 2030, Latif said.

The nuclear authority has picked 20 potential sites for the reactors and Latif suggested that the first contracts could be signed in the next year.

It won’t be Iraq’s first attempt to go nuclear. Four decades ago, an Israeli air strike destroyed a reactor under construction south of Baghdad. The Israelis alleged the facility, called Osirak, was aimed at producing nuclear weapons for use against them. Iraq suffered more than a decade of violence and upheaval after the 2003 U.S. invasion, which was also motivated by allegations that Iraq wanted to develop weapons.

 

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Duke Energy seeks changes in how solar owners are paid for electricity

Duke Energy Net Metering Proposal updates rooftop solar compensation with time-of-use rates, lower grid credits, and a minimum charge, aligning payments with electricity demand in North Carolina pending regulators' approval.

 

Key Points

A plan to swap flat credits for time-of-use rates and a minimum charge for rooftop solar customers in North Carolina.

✅ Time-of-use credits vary by grid demand

✅ $10 minimum use charge plus $14 basic fee

✅ Aims to align solar payouts with actual electricity value

 

Duke Energy has proposed new rules for how owners of rooftop solar panels are paid for electricity they send to the electric grid. It could mean more complexity and lower payments, but the utility says rates would be fairer.

State legislators have called for changes in the payment rules — known as "net metering" policies that allow households to sell power back to energy firms.

Right now, solar panel owners who produce more electricity than they need get credits on their bills, equal to whatever they pay for electricity. Under the proposed changes, the credit would be lower and would vary according to electricity demand, said Duke spokesperson Randy Wheeless.

"So in a cold winter morning, like now, you would get more, but maybe in a mild spring day, you would get less," Wheeless said Tuesday. "So, it better reflects what the price of electricity is."

Besides setting rates by time of use, solar owners also would have to pay a minimum of $10 a month for electricity, even if they don't use any from the grid. That's on top of Duke's $14 basic charge. Duke said it needs the extra revenue to pay for grid infrastructure to serve solar customers.

The proposal is the result of an agreement between Duke and solar industry groups — the North Carolina Sustainable Energy Association; the Southern Environmental Law Center, which represented Vote Solar and the Southern Alliance for Clean Energy; solar panel maker Sunrun Inc.; and the Solar Energy Industries Association.

The deal is similar to one approved by regulators in South Carolina last year, while in Nova Scotia a solar charge was delayed after controversy.

Daniel Brookshire of the North Carolina Sustainable Energy Association said he hopes the agreement will help the solar industry.

"We reached an agreement here that we think will provide certainty over the next decade, at least, for those interested in pursuing solar for their homes, and for our members who are solar installers," Brookshire said.

But other environmental and consumer groups oppose the changes, amid debates over who pays for grid upgrades elsewhere. Jim Warren with NC WARN said the rules would slow the expansion of rooftop solar in North Carolina.

"It would make it even harder for ordinary people to go solar," Warren said. "This would make it more complicated and more expensive, even for wealthier homeowners."

State regulators still must approve the proposal, even as courts weigh aspects of the electricity monopoly in related solar cases. If state regulators approve it, rates for new net metering customers would take effect Jan. 1, 2023.

 

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Climate change: Greenhouse gas concentrations again break records

Rising Greenhouse Gas Concentrations drive climate change, with CO2, methane, and nitrous oxide surging; WMO data show higher radiative forcing, elevated pre-industrial baselines, and persistent atmospheric concentrations despite Paris Agreement emissions pledges.

 

Key Points

Increasing atmospheric CO2, methane, and nitrous oxide levels that raise radiative forcing and drive warming.

✅ WMO data show CO2 at 407.8 ppm in 2018, above decade average

✅ Methane and nitrous oxide surged, elevating total radiative forcing

✅ Concentrations differ from emissions; sinks absorb about half

 

The World Meteorological Organization (WMO) says the increase in CO2 was just above the average rise recorded over the last decade.

Levels of other warming gases, such as methane and nitrous oxide, have also surged by above average amounts.

Since 1990 there's been an increase of 43% in the warming effect on the climate of long lived greenhouse gases.

The WMO report looks at concentrations of warming gases in the atmosphere rather than just emissions.

The difference between the two is that emissions refer to the amount of gases that go up into the atmosphere from the use of fossil fuels, such as burning coal for coal-fired electricity generation and from deforestation.

Concentrations are what's left in the air after a complex series of interactions between the atmosphere, the oceans, the forests and the land. About a quarter of all carbon emissions are absorbed by the seas, and a similar amount by land and trees, while technologies like carbon capture are being explored to remove CO2.

Using data from monitoring stations in the Arctic and all over the world, researchers say that in 2018 concentrations of CO2 reached 407.8 parts per million (ppm), up from 405.5ppm a year previously.

This increase was above the average for the last 10 years and is 147% of the "pre-industrial" level in 1750.

The WMO also records concentrations of other warming gases, including methane and nitrous oxide, and some countries have reported declines in certain potent gases, as noted in US greenhouse gas controls reports, though global levels remain elevated. About 40% of the methane emitted into the air comes from natural sources, such as wetlands, with 60% from human activities, including cattle farming, rice cultivation and landfill dumps.

Methane is now at 259% of the pre-industrial level and the increase seen over the past year was higher than both the previous annual rate and the average over the past 10 years.

Nitrous oxide is emitted from natural and human sources, including from the oceans and from fertiliser-use in farming. According to the WMO, it is now at 123% of the levels that existed in 1750.

Last year's increase in concentrations of the gas, which can also harm the ozone layer, was bigger than the previous 12 months and higher than the average of the past decade.

What concerns scientists is the overall warming impact of all these increasing concentrations. Known as total radiative forcing, this effect has increased by 43% since 1990, and is not showing any indication of stopping.

There is no sign of a slowdown, let alone a decline, in greenhouse gases concentration in the atmosphere despite all the commitments under the Paris agreement on climate change and the ongoing global energy transition efforts," said WMO Secretary-General Petteri Taalas.

"We need to translate the commitments into action and increase the level of ambition for the sake of the future welfare of mankind," he added.

"It is worth recalling that the last time the Earth experienced a comparable concentration of CO2 was three to five million years ago. Back then, the temperature was 2-3C warmer, sea level was 10-20m higher than now," said Mr Taalas.

The UN Environment Programme will report shortly on the gap between what actions countries are taking to cut carbon, for example where Australia's emissions rose 2% recently, and what needs to be done to keep under the temperature targets agreed in the Paris climate pact.

Preliminary findings from this study, published during the UN Secretary General's special climate summit last September, indicated that emissions continued to rise during 2018, although global emissions flatlined in 2019 according to the IEA.

Both reports will help inform delegates from almost 200 countries who will meet in Madrid next week for COP25, following COP24 in Katowice the previous year, the annual round of international climate talks.

 

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How the dirtiest power station in western Europe switched to renewable energy

Drax Biomass Conversion accelerates renewable energy by replacing coal with wood pellets, sustainable forestry feedstock, and piloting carbon capture and storage, supporting the UK grid, emissions cuts, and a net-zero pathway.

 

Key Points

Drax Biomass Conversion is Drax's shift from coal to biomass with CCS pilots to cut emissions and aid UK's net-zero.

✅ Coal units converted to biomass wood pellets

✅ Sourced from sustainable forestry residues

✅ CCS pilots target lifecycle emissions cuts

 

A power station that used to be the biggest polluter in western Europe has made a near-complete switch to renewable energy, mirroring broader shifts as Denmark's largest energy company plans to end coal by 2023.

The Drax Power Station in Yorkshire, England, used to spew out millions of tons of carbon dioxide a year by burning coal. But over the past eight years, it has overhauled its operations by converting four of its six coal-fired units to biomass. The plant's owners say it now generates 15% of the country's renewable power, as Britain recently went a full week without coal power for the first time.

The change means that just 6% of the utility's power now comes from coal, as the wider UK coal share hits record lows across the national electricity system. The ultimate goal is to stop using coal altogether.

"We've probably reduced our emissions more than any other utility in the world by transforming the way we generate power," Will Gardner, CEO of the Drax Group, told CNN Business.

Subsidies have helped finance the switch to biomass, which consists of plant and agricultural matter and is viewed as a promising substitute for coal, and utilities such as Nova Scotia Power are also increasing biomass use. Last year, Drax received £789 million ($1 billion) in government support.

 

Is biomass good for the environment?

While scientists disagree over the extent to which biomass as a fuel is environmentally friendly, and some environmentalists urge reducing biomass use amid concerns about lifecycle emissions, Drax highlights that its supplies come from from sustainably managed and growing forests.

Most of the biomass used by Drax consists of low-grade wood, sawmill residue and trees with little commercial value from the United States. The material is compressed into sawdust pellets.

Gardner says that by purchasing bits of wood not used for construction or furniture, Drax makes it more financially viable for forests to be replanted. And planting new trees helps offset biomass emissions.

Forests "absorb carbon as they're growing, once they reach maturity, they stop absorbing carbon," said Raphael Slade, a senior research fellow at Imperial College London.

But John Sterman, a professor at MIT's Sloan School of Management, says that in the short term burning wood pellets adds more carbon to the atmosphere than burning coal.

That carbon can be absorbed by new trees, but Sterman says the process can take decades.

"If you're looking at five years, [biomass is] not very good ... If you're looking at a century-long time scale, which is the sort of time scale that many foresters plan, then [biomass] can be a lot more beneficial," says Slade.

 

Carbon capture

Enter carbon capture and storage technology, which seeks to prevent CO2 emissions from entering the atmosphere and has been touted as a possible solution to the climate crisis.

Drax, for example, is developing a system to capture the carbon it produces from burning biomass. But that could be 10 years away.

 

The Coal King is racing to avoid bankruptcy

The power station is currently capturing just 1 metric ton of CO2 emissions per day. Gardner says it hopes to increase this to 10,000 metric tons per day by the mid to late 2020s.

"The technology works but scaling it up and rolling it out, and financing it, are going to be significant challenges," says Slade.

The Intergovernmental Panel on Climate Change shares this view. The group said in a 2018 report that while the potential for CO2 capture and storage was considerable, its importance in the fight against climate change would depend on financial incentives for deployment, and whether the risks of storage could be successfully managed. These include a potential CO2 pipeline break.

In the United Kingdom, the government believes that carbon capture and storage will be crucial to reaching its goal of achieving net-zero greenhouse gas emissions by 2050, even as low-carbon generation stalled in 2019 according to industry analysis.

It has committed to consulting on a market-based industrial carbon capture framework and in June awarded £26 million ($33 million) in funding for nine carbon capture, usage and storage projects, amid record coal-free generation on the British grid.

 

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Data Show Clean Power Increasing, Fossil Fuel Decreasing in California

California clean electricity accelerates with renewables as solar and wind surge, battery storage strengthens grid resilience, natural gas declines, and coal fades, advancing SB 100 targets, carbon neutrality goals, and affordable, reliable power statewide.

 

Key Points

California clean electricity is the state's transition to renewable, zero-carbon power, scaling solar, wind and storage.

✅ Solar generation up nearly 20x since 2012

✅ Natural gas power down 20%; coal nearly phased out

✅ Battery storage shifts daytime surplus to evening demand

 

Data from the California Energy Commission (CEC) highlight California’s continued progress toward building a more resilient grid, achieving 100 percent clean electricity and meeting the state’s carbon neutrality goals.

Analysis of the state’s Total System Electric Generation report shows how California’s power mix has changed over the last decade. Since 2012:

Solar generation increased nearly twentyfold from 2,609 gigawatt-hours (GWh) to 48,950 GWh.

  • Wind generation grew by 63 percent.
  • Natural gas generation decreased 20 percent.
  • Coal has been nearly phased-out of the power mix, and renewable electricity surpassed coal nationally in 2022 as well.

In addition to total utility generation, rooftop solar increased by 10 times generating 24,309 GWh of clean power in 2022. The state’s expanding fleet of battery storage resources also help support the grid by charging during the day using excess renewable power for use in the evening.

“This latest report card showing how solar energy boomed as natural gas powered electricity experienced a steady 20 percent decline over the last decade is encouraging,” said CEC Vice Chair Siva Gunda. “Even as climate impacts become increasingly severe, California remains committed to transitioning away from polluting fossil fuels and delivering on the promise to build a future power grid that is clean, reliable and affordable.”

Senate Bill 100 (2018) requires 100 percent of California’s electric retail sales be supplied by renewable and zero-carbon energy sources by 2045. To keep the state on track, last year Governor Gavin Newsom signed SB 1020, establishing interim targets of 90 percent clean electricity by 2035 and 95 percent by 2040.

The state monitors progress through the Renewables Portfolio Standard (RPS), which tracks the power mix of retail sales, and regional peers such as Nevada's RPS progress offer useful comparison. The latest data show that in 2021 more than 37 percent of the state’s electricity came from RPS-eligible sources such as solar and wind, an increase of 2.7 percent compared to 2020. When combined with other sources of zero-carbon energy such as large hydroelectric generation and nuclear, nearly 59 percent of the state’s retail electricity sales came from nonfossil fuel sources.

The total system electric generation report is based on electric generation from all in-state power plants rated 1 megawatt (MW) or larger and imported utility-scale power generation. It reflects the percentage of a specific resource compared to all power generation, not just retail sales. The total system electric generation report accounts for energy used for water conveyance and pumping, transmission and distribution losses and other uses not captured under RPS.

 

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Iran, Iraq Discuss Further Cooperation in Energy Sector

Iran-Iraq Electricity Cooperation advances with power grid synchronization, cross-border energy trade, 400-kV transmission lines, and education partnerships, boosting grid reliability, infrastructure investment, and electricity exports between Tehran and Baghdad for improved supply and stability.

 

Key Points

A bilateral initiative to synchronize grids, expand networks, and sustain electricity exports, improving reliability.

✅ 400-kV Amarah-Karkheh line enables synchronized operations.

✅ Extends electricity export contracts to meet Iraq demand.

✅ Enhances grid reliability, training, and infrastructure investment.

 

Aradakanian has focused his one-day visit to Iraq on discussions pertaining to promoting bilateral collaboration between the two neighboring nations in the field of electricity, grid development deals and synchronizing power grid between Tehran and Baghdad, cooperating in education, and expansion of power networks.

He is also scheduled to meet with Iraqi top officials in a bid to boost cooperation in the relevant fields.

Back in December 2019, Ardakanian announced that Iran will continue exports of electricity to Iraq by renewing earlier contract as it is supplying about 40% of Iraq's power today.

"Iran has signed a 3-year-long cooperation agreement with Iraq to help the country's power industry in different aspects. The documents states at its end that we will export electricity to Iraq as far as they need," Ardakanian told FNA on December 9, 2019.

The contract to "export Iran's electricity" to Iraq will be extended, he added.

Ardakanian also said that Iran and Iraq's power grids have become synchronized in a move that supports Iran's regional power hub plans since a month ago.

In 2004 Iran started selling electricity to Iraq. Iran electricity exports to the western neighbor are at its highest level of 1,361 megawatts per day now, as the country weighs summer power sufficiency ahead of peak demand.

The new Amarah-Karkheh 400-KV transmission line stretching over 73 kilometers, is now synchronized to provide electricity to both countries, reflecting regional power export trends as well. It also paves the way for increasing export to power-hungry Iraq in the near future.

With synchronization of the two grids, the quality of electricity in Iraq will improve as the country explores nuclear power options to tackle shortages.

According to official data, 82% of Iraq's electricity is generated by thermal power plants that use gas as feedstock, while Iran is converting thermal plants to combined cycle to save energy. This is expected to reach 84% by 2027.

 

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