Power plant crippled by lightning

By Knight Ridder Tribune


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A lightning strike to a north central Wisconsin power plant will carry a hefty price: $34 million.

The tab for Wisconsin Public Service Corp. breaks down to $8.3 million for repairs to the plant and $26 million in higher costs for power the utility must purchase to replace that generated by the plant, near Wausau. The Oct. 6 strike was the second time in two years that the plant was knocked out of service because of a lightning strike.

Wisconsin Public Service Corp., based in Green Bay, said the damage was worse than it first projected. A detailed inspection of the plant revealed damage to the power plant's turbine and generator rotors, said Terry Jensky, vice president of energy supply operations at Wisconsin Public Service.

The plant is expected to be out of service until late 2007 or early 2008, instead of this month.

The plant generates 321 megawatts of electricity, or enough to power more than 160,000 homes. In August 2006, the same power plant was struck by lightning, resulting in appeals by the utility for customers to curtail electricity use in the Wausau, Minocqua and Rhinelander areas.

The utility also cut off power supply to large manufacturing customers. The plant returned to service within a few days, a utility spokeswoman said.

If there's any bright side to the second lightning strike, Jensky said, "at least we were through the summer when peak demand for air-conditioning loads can create an increased electric reliability issue." The damage came despite installation last year of "a state-of-the-art lightning suppression" system that was in operation at the time of the latest strike, the utility says in a letter filed with regulators.

State regulators have authorized the utility to seek to recover the $26 million from its customers at a later date. A request to recover the repair costs of $8.3 million is pending.

In a letter to state regulators, the utility says the lightning strike would reduce profit by 0.5% in 2007 - which would translate to 7 cents a share in lower earnings for the company's parent company, Integrys Energy Group Inc. of Chicago. That financial hit wouldn't reduce earnings if the state Public Service Commission approves the utility's proposal seeking to recover those costs from customers at a later date.

The calls to conserve power last summer after the lightning strike and a fire at the plant provided a stark reminder of the problems experienced by the state's power grid in the past decade. The state experienced widespread electricity shortages in the late 1990s that spawned construction of power plants and high-voltage transmissions lines.

That building boom includes two Wausau-area projects: a $750 million coal-fired power plant that will open next year near the plant struck by lightning, and a controversial 345,000-volt, $420 million power line that will extend from Wausau to Duluth, Minn. Both projects are expected to be generating and distributing power by next summer.

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Hydro once made up around half of Alberta's power capacity. Why does Alberta have so little now?

Alberta Hydropower Potential highlights renewable energy, dams, reservoirs, grid flexibility, contrasting wind and solar growth with limited investment, regulatory hurdles, river basin resources, and decarbonization pathways across Athabasca, Peace, and Slave River systems.

 

Key Points

It is the technical capacity for new hydro in Alberta's river basins to support a more reliable, lower carbon grid.

✅ 42,000 GWh per year developable hydro identified in studies.

✅ Major potential in Athabasca, Peace, and Slave River basins.

✅ Barriers include high capital costs, market design, water rights.

 

When you think about renewable energy sources on the Prairies, your mind may go to the wind farms in southern Alberta, or even the Travers Solar Project, southeast of Calgary.

Most of the conversation around renewable energy in the province is dominated by advancements in solar and wind power, amid Alberta's renewable energy surge that continues to attract attention. 

But what about Canada's main source of electricity — hydro power?

More than half of Canada's electricity is generated from hydro sources, with 632.2 terawatt-hours produced as of 2019. That makes it the fourth largest installed capacity of hydropower in the world. 

But in Alberta, it's a different story. 

Currently, hydro power contributes between three and five per cent of Alberta's energy mix, while fossil fuels make up about 89 per cent.

According to Canada's Energy Future report from the Canada Energy Regulator, by 2050 it will make up two per cent of the province's electricity generation shares.

So why is it that a province so rich in mountains and rivers has so little hydro power?


Hydro's history in Alberta
Hydro power didn't always make up such a small sliver of Alberta's electricity generation. Hydro installations began in the early 20th century as the province's population exploded. 

Grant Berg looks after engineering for hydro for TransAlta, Alberta's largest producer of hydro power with 17 facilities across the province.

"Our first plant was Horseshoe, which started in 1911 that we formed as Calgary Power," he said. 

"It was really in response to the City of Calgary growing and having some power needs."

Berg said in 1913, TransAlta's second installation, the Kananaskis Plant, started as Calgary continued to grow.

A historical photo of a hydro-electric dam in Kananaskis Alta. taken in 1914.
Hydro power plant in Kananaskis as seen in 1914. (Glenbow Archives)
Some bigger installations were built in the 1920s, including Ghost reservoir, but by mid-century population growth increased.

"Quite a large build out really, I think in response to the growth in Alberta following the war. So through the 1950s really quite a large build out of hydro from there."

By the 1950s, around half of the province's installed capacity was hydro power.

"Definitely Calgary power was all hydro until the 1950s," said Berg. 


Hydro potential in the province 
Despite the current low numbers in hydroelectricity, Alberta does have potential. 

According to a 2010 study, there is approximately 42,000 gigawatt-hours per year of remaining developable hydroelectric energy potential at identified sites. 

An average home in Alberta uses around 7,200 kilowatt-hours of electricity per year, meaning that the hydro potential could power 5.8 million homes each year. 

"This volume of energy could be sufficient to serve a significant amount of Alberta's load and therefore play a meaningful role in the decarbonization of the province's electric system," the Alberta Electric System Operator said in its 2022 Pathways to Net-Zero Emissions report.

Much of that potential lies in northern Alberta, in the Athabasca, Peace and Slave River basins.

The AESO report says that despite the large resource potential, Alberta's energy-only market framework has attracted limited investment in hydroelectric generation. 

Hydro power was once a big deal in Alberta, but investment in the industry has been in decline since the 1950s. Climate change reporter Christy Climenhaga explains why.
So why does Alberta leave out such a large resource potential on the path to net zero?

The government of Alberta responded to that question in a statement. 

"Hydro facilities, particularly large scale ones involving dams, are associated with high costs and logistical demands," said the Ministry of Affordability and Utilities. 

"Downstream water rights for other uses, such as irrigation, further complicate the development of hydro projects."

The ministry went on to say that wind and solar projects have increased far more rapidly because they can be developed at relatively lower cost and shorter timelines, and with fewer logistical demands.

"Sources from wind power and solar are increasingly more competitive," said Jean-Denis Charlebois, chief economist with the Canadian Energy Regulator. 


Hydro on the path to net zero
Hydro power is incredibly important to Canada's grid, and will remain so, despite growth in wind and solar power across the province.

Charlebois said that across Canada, the energy make-up will depend on the province. 

"Canadian provinces will generate electricity in very different ways from coast to coast. The major drivers are essentially geography," he said. 

Charlebois says that in British Columbia, Manitoba, Quebec and Newfoundland and Labrador, hydropower generation will continue to make up the majority of the grid.

"In Alberta and Saskatchewan, we see a fair bit of potential for wind and solar expansion in the region, which is not necessarily the case on Canada's coastlines," he said.

And although hydro is renewable, it does bring its adverse effects to the environment — land use changes, changes in flow patterns, fish populations and ecosystems, which will have to be continually monitored. 

"You want to be able to manage downstream effects; make sure that you're doing all the proper things for the environment," said Ryan Braden, director of mining and hydro at TransAlta.

Braden said hydro power still has a part to play in Alberta, even with its smaller contributions to the future grid. 

"It's one of those things that, you know, the wind doesn't blow or the sun doesn't shine, this is here. The way we manage it, we can really support that supply and demand," he said.

 

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Iran Says Deals to Rehabilitate, Develop Iraq Power Grid Finalized

Iran-Iraq Power Grid Deals reinforce electricity and natural gas ties, upgrading transmission in Karbala and Najaf, repairing transformers, easing sanctions bottlenecks, and weighing GCC interconnection to diversify supply and reduce distribution losses across Iraq.

 

Key Points

Agreements to rehabilitate Iraq's grid, cut losses, and secure power via Iranian gas, electricity, and upgrades.

✅ Reduce distribution losses in Karbala and Najaf

✅ Repair and replace damaged distribution transformers

✅ Coordinate payments to TAVANIR amid US sanctions

 

Iran and Iraq have finalized two deals to rehabilitate and develop the power grid of Iraq, while Iran is upgrading thermal plants to combined cycle at home to save energy, IRNA cited the Iranian Energy Minister Reza Ardakanian.

Ardakanian met his Iraqi counterpart Majid Mahdi Hantoush in Tehran on Tuesday evening for talks on further energy cooperation on the sidelines of Prime Minister Mustafa al-Kadhimi’s trip to the Islamic Republic on his first foreign visit.

“It was decided that the contracts related to reducing losses on the electricity distribution network in the provinces of Karbala and Najaf, as well as the contract for repairing Iraq’s distribution transformers would be finalized and signed,” the Iranian minister said.

Iraq relies on Iran for natural gas that generates as much as 45 percent of its electricity, with Iran supplying 40% of Iraq’s power according to sector reports. Iran transmits another 1,200 MW directly, and has regional power hub plans as well, making itself an indispensable energy source for its Arab neighbor, but the United States is trying to pry Baghdad away from Tehran’s orbit.

The US has been enlisting its companies and allies such as Saudi Arabia to replace Iran as Iraq’s source of energy.

Iran’s money from exports of gas and electricity has accumulated in bank accounts in Iraq, because US sanctions are preventing Tehran from repatriating it.

In January, an official said the sanctions were giving Iran a run for five billion dollars, “sedimenting” at the Central Bank of Iraq, because Tehran could not access it.

Ardakanian said the issue was brought up in the discussions on Tuesday and it was agreed that “the payment of part of TAVANIR (Iran Power Generation and Transmission Company)’s claims will start from the end of July”.

The US administration is pushing for a deal between Washington, Baghdad and six Persian Gulf states to connect Iraq’s nationwide power grid to that of the Persian Gulf Cooperation Council, while Uzbekistan looks to export power to Afghanistan as regional linkages expand.

The US State Department said in a statement last Thursday that the six countries that make up the (Persian) Gulf Cooperation Council Interconnection Authority (GCCIA) — Saudi Arabia, Kuwait, Bahrain, Qatar, Oman and the UAE — had affirmed their shared support for the project to supply electricity to Iraq.

Iraq needs more than 23,000 MW of electricity to meet its domestic demand, and is exploring nuclear power plans to tackle shortages, but years of war following the 2003 US invasion have left its power infrastructure in tatters and a deficit of some 7,000 MW.

In the past, officials in Baghdad have said there is no easy substitute to imports from Iran because it will take years to adequately build up Iraq’s energy infrastructure, and meeting summer electricity needs remains a persistent challenge.

They have said American demand acknowledges neither Iraq’s energy needs nor the complex relations between Baghdad and Tehran.

In addition to natural gas and electricity, Iraq imports a wide range of goods from Iran including food, agricultural products, home appliances, and air conditioners.

On Tuesday, the Iraqi prime minister said during a joint news conference with Iranian President Hassan Rouhani that the purpose of his trip to Tehran was to strengthen historical ties between the two countries, especially in light of the challenges they faced as a result of the coronavirus outbreak and the fall of oil prices.

“In the face of such challenges, we need coordination between the two countries in a way that serves the interests of Iran and Iraq.”

Both Iran and Iraq, Kadhimi said, suffer from economic problems, adding the two countries need comprehensive and inclusive cooperation to overcome them.

Kadhimi said Iran-Iraq relations are not merely due to the geographical location of the two countries and their 1,450-km border, adding the ties are based on religion and culture and rooted in history.

“I am reiterating to my brothers in the Islamic Republic of Iran that the Iraqi nation is eager to have excellent relations with the Islamic Republic of Iran based on the principle of non-interference in the internal affairs of the two countries.”

Kadhimi said Iran and Iraq fought against terrorism and Takfiri groups together, and the Islamic Republic of Iran was one of the first countries to stand by Iraq.

“We will not forget this. That is why Iraq has stood with Iran to help it overcome economic challenges and turned to a big market for trade with Iran,” he said.

“We seek stability in Iraq and our philosophy and view of Iran is that we consider Iran a stable, strong, prosperous and progressive country, and this fact is in the interest of Iraq and the territorial integrity of the region,” he added.

According to Kadhimi, the two sides discussed implementing agreements between them, including connecting their railway through Khorramshahr in Iran and Basra in Iraq, adding he was very confident the agreements would be implemented soon.

Iraq’s delegation included the ministers of foreign affairs, finance, health, and planning, as well as Kadhimi’s national security adviser, some of whom also met their Iranian counterparts.

Last year, Iran’s exports to Iraq amounted to nearly $9 billion, IRNA reported. It said the two nations will discuss increasing that amount to $20 billion.

“The two governments’ will is to expand bilateral trade to $20 billion,” Rouhani said after an hour-long meeting with the Iraqi prime minister.

 

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Ontario utilities team up to warn customers about ongoing scams

Ontario Utility Scam Alert: protect against phishing, spoofed calls, texts, and emails, disconnection threats, and demands for prepaid cards or bitcoin. Tips from Alectra, Elexicon, Hydro One, Hydro Ottawa, and Toronto Hydro.

 

Key Points

A joint warning by Ontario utilities on tactics and steps to prevent customer fraud, phishing, and spoofed contacts.

✅ Verify bills; call your utility using the official number.

✅ Ignore links; do not accept unexpected e-transfers.

✅ Never pay with gift cards, prepaid cards, or bitcoin.

 

Five of Ontario's largest utilities have joined forces to raise awareness about ongoing sophisticated utility scams targeting utility customers.

Some common tactics fraudsters use to target Ontarians include impersonation of the local utility or its employees; sending threatening phone calls, texts and emails; or showing up in-person at a customer's home or business and requesting personal information or payment. The requests can include pressure for immediate payment, threats to disconnect service the same day, and demands to purchase prepaid debit cards, gift cards or bitcoin.

The utilities are encouraging all customers to protect themselves and are providing them with the following tips to stay safe, noting that customers want more choice and flexibility in how they manage accounts:

  • Never make a payment for a charge that isn't listed on your most recent bill
  • Ignore text messages or emails with suspicious links promising refunds
  • Don't call the number provided to you — instead, call your utility directly to check the status of your account
  • Only provide personal information or details about your account when you have initiated the contact with the utility representative  
  • Utility companies will never threaten immediate disconnection for non-payment, and many offer relief programs during hardship
  • If you feel threatened in any way, contact your local police
  • Steps you can take to protect yourself against fraud:

Take five minutes to ask additional questions and listen to your instincts — if something doesn't seem right, ask someone about it, and look for news of official utility support efforts that confirm legitimate outreach

  • Immediately hang up on suspicious phone calls
  • Don't click any links in emails/text messages asking you to accept electronic transfers
  • Avoid sharing personal information
  • Always compare bills to previous ones, including the dollar amount and account number, and stay informed about any official rate changes from your utility
  • Reporting suspicious behaviour, including suspected electricity theft, helps authorities

If you believe you may be a victim of fraud, please contact the Canadian Anti-Fraud Centre at 1-888-495-8501 and your local utility.

Customers can find more information at:

  • Alectra Utilities
  • Elexicon Energy
  • Hydro One
  • Hydro Ottawa 
  • Toronto Hydro

 

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A Texas-Sized Gas-for-Electricity Swap

Texas Heat Pump Electrification replaces natural gas furnaces with electric heating across ERCOT, cutting carbon emissions, lowering utility bills, shifting summer peaks to winter, and aligning higher loads with strong seasonal wind power generation.

 

Key Points

Statewide shift from gas furnaces to heat pumps in Texas, reducing emissions and bills while moving grid peak to winter.

✅ Up to $452 annual utility savings per household

✅ CO2 cuts up to 13.8 million metric tons in scenarios

✅ Winter peak rises, summer peak falls; wind aligns with load

 

What would happen if you converted all the single-family homes in Texas from natural gas to electric heating?

According to a paper from Pecan Street, an Austin-based energy research organization, the transition would reduce climate-warming pollution, save Texas households up to $452 annually on their utility bills, and flip the state from a summer-peaking to a winter-peaking system. And that winter peak would be “nothing the grid couldn’t evolve to handle,” according to co-author Joshua Rhodes, a view echoed by analyses outlining Texas grid reliability improvements statewide today.

The report stems from the reality that buildings must be part of any comprehensive climate action plan.

“If we do want to decarbonize, eventually we do have to move into that space. It may not be the lowest-hanging fruit, but eventually we will have to get there,” said Rhodes.

Rhodes is a founding partner of the consultancy IdeaSmiths and an analyst at Vibrant Clean Energy. Pecan Street commissioned the study, which is distilled from a larger original analysis by IdeaSmiths, at the request of the nonprofit Environmental Defense Fund.

In an interview, Rhodes said, “The goal and motivation were to put bounding on some of the claims that have been made about electrification: that if we electrify a lot of different end uses or sectors of the economy...power demand of the grid would double.”

Rhodes and co-author Philip R. White used an analysis tool from the National Renewable Energy Laboratory called ResStock to determine the impact of replacing natural-gas furnaces with electric heat pumps in homes across the ERCOT service territory, which encompasses 90 percent of Texas’ electricity load.

Rhodes and White ran 80,000 simulations in order to determine how heat pumps would perform in Texas homes and how the pumps would impact the ERCOT grid.

The researchers modeled the use of “standard efficiency” (ducted, SEER 14, 8.2 HSPF air-source heat pump) and “superior efficiency” (ductless, SEER 29.3, 14 HSPF mini-split heat pump) heat pump models against two weather data sets — a typical meteorological year, and 2011, which had extreme weather in both the winter and summer and highlighted blackout risks during severe heat for many regions.

Emissions were calculated using Texas’ power sector data from 2017. For energy cost calculations, IdeaSmiths used 10.93 cents per kilowatt-hour for electricity and 8.4 cents per therm for natural gas.

Nothing the grid can't handle
Rhodes and White modeled six scenarios. All the scenarios resulted in annual household utility bill savings — including the two in which annual electricity demand increased — ranging from $57.82 for the standard efficiency heat pump and typical meteorological year to $451.90 for the high-efficiency heat pump and 2011 extreme weather year.

“For the average home, it was cheaper to switch. It made economic sense today to switch to a relatively high-efficiency heat pump,” said Rhodes. “Electricity bills would go up, but gas bills can go down.”

All the scenarios found carbon savings too, with CO2 reductions ranging from 2.6 million metric tons with a standard efficiency heat pump and typical meteorological year to 13.8 million metric tons with the high-efficiency heat pump in 2011-year weather.

Peak electricity demand in Texas would shift from summer to winter. Because heat pumps provide both high-efficiency space heating and cooling, in the scenario with “superior efficiency” heat pumps, the summer peak drops by nearly 24 percent to 54 gigawatts compared to ERCOT’s 71-gigawatt 2016 summer peak, even as recurring strains on the Texas power grid during extreme conditions persist.

The winter peak would increase compared to ERCOT’s 66-gigawatt 2018 winter peak, up by 22.73 percent to 81 gigawatts with standard efficiency heat pumps and up by 10.6 percent to 73 gigawatts with high-efficiency heat pumps.

“The grid could evolve to handle this. This is not a wholesale rethinking of how the grid would have to operate,” said Rhodes.

He added, “There would be some operational changes if we went to a winter-peaking grid. There would be implications for when power plants and transmission lines schedule their downtime for maintenance. But this is not beyond the realm of reality.”

And because Texas’ wind power generation is higher in winter, a winter peak would better match the expected higher load from all-electric heating to the availability of zero-carbon electricity.

 

A conservative estimate
The study presented what are likely conservative estimates of the potential for heat pumps to reduce carbon pollution and lower peak electricity demand, especially when paired with efficiency and demand response strategies that can flatten demand.

Electric heat pumps will become cleaner as more zero-carbon wind and solar power are added to the ERCOT grid, as utilities such as Tucson Electric Power phase out coal. By the end of 2018, 30 percent of the energy used on the ERCOT grid was from carbon-free sources.

According to the U.S. Energy Information Administration, three in five Texas households already use electricity as their primary source of heat, much of it electric-resistance heating. Rhodes and White did not model the energy use and peak demand impacts of replacing that electric-resistance heating with much more energy efficient heat pumps.

“Most of the electric-resistance heating in Texas is located in the very far south, where they don’t have much heating at all,” Rhodes said. “You would see savings in terms of the bills there because these heat pumps definitely operate more efficiently than electric-resistance heating for most of the time.”

Rhodes and White also highlighted areas for future research. For one, their study did not factor in the upfront cost to homeowners of installing heat pumps.

“More study is needed,” they write in the Pecan Street paper, “to determine the feasibility of various ‘replacement’ scenarios and how and to what degree the upgrade costs would be shared by others.”

Research from the Rocky Mountain Institute has found that electrification of both space and water heating is cheaper for homeowners over the life of the appliances in most new construction, when transitioning from propane or heating oil, when a gas furnace and air conditioner are replaced at the same time, and when rooftop solar is coupled with electrification, aligning with broader utility trends toward electrification.

More work is also needed to assess the best way to jump-start the market for high-efficiency all-electric heating. Rhodes believes getting installers on board is key.

“Whenever a homeowner’s making a decision, if their system goes out, they lean heavily on what the HVAC company suggests or tells them because the average homeowner doesn’t know much about their systems,” he said.

More work is also needed to assess the best way to jump-start the market for high-efficiency all-electric heating, and how utility strategies such as smart home network programs affect adoption too. Rhodes believes getting installers on board is key.

 

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Ontario hydro rates set to increase Nov. 1, Ontario Energy Board says

Ontario Electricity Rebate clarifies hydro rates as OEB aligns bills with inflation, shows true cost per kilowatt hour, and replaces Fair Hydro Plan; transparent on-bill credit offsets increases tied to nuclear refurbishment and supply costs.

 

Key Points

A line-item credit on Ontario hydro bills that offsets higher electricity costs and reflects OEB-set rates.

✅ Starts Nov. 1 with rates in line with inflation

✅ Shows true per-kWh cost plus separate rebate line

✅ Driven by nuclear refurbishment and supply costs

 

The Ontario Energy Board says electricity rate changes for households and small businesses will be going up starting next week.

The agency says rates are scheduled to increased by about $1.99 or nearly 2% for a typical residential customer who uses 700 kilowatt hours per month.

The provincial government said in March it would continue to subsidize hydro rates, through legislation to lower rates, and hold any increases to the rate of inflation.

The OEB says the new rates, which the board says are “in line” with inflation, will take effect Nov. 1 as changes for electricity consumers roll out and could be noticed on bills within a few weeks of that date.

Prices are increasing partly due to government legislation aimed at reflecting the actual cost of supply on bills, and partly due to the refurbishment of nuclear facilities, contributing to higher hydro bills for some consumers.

So, effective November 1, Ontario electricity bills will show the true cost of power, after a period of a fixed COVID-19 hydro rate, and will include the new Ontario Electricity Rebate.

Previously the electricity rebate was concealed within the price-per-kilowatt-hour line item on electricity statements, prompting Hydro One bill redesign discussions to improve clarity. This meant customers could not see how much the government rebate was reducing their monthly costs, and bills did not display the true cost of electricity used.

"People deserve facts and accountability, especially when it comes to hydro costs," said Energy Minister Rickford.

The new Ontario Electricity Rebate will appear as a transparent on-bill line item and will replace the former government's Fair Hydro Plan says a government news release. This change comes in response to the Auditor General's special report on the former government's Fair Hydro Plan which revealed that "the government created a needlessly complex accounting/financing structure for the electricity rate reduction in order to avoid showing a deficit or an increase in net debt."

"The Electricity Distributors Association commends the government's commitment to making Ontario's electricity bills more transparent," said Teresa Sarkesian, President of the Electricity Distributors Association. "As the part of our electricity system that is closest to customers, local hydro utilities appreciated the opportunity to work with the government on implementing this important initiative. We worked to ensure that customers who receive their electricity bill will have a clear understanding of the true cost of power and the amount of their on-bill rebate. Local hydro utilities are focused on making electricity more affordable, reducing red tape, and providing customers with a modern and reliable electricity system that works for them."

The average customer will see the electricity line on their bill rise, showing the real cost per kilowatt hour. The new Ontario Electricity Rebate will compensate for that rise, and will be displayed as a separate line item on hydro bills. The average residential bill will rise in line with the rate of inflation.

 

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Rising Solar and Wind Curtailments in California

California Renewable Energy Curtailment highlights grid congestion, midday solar peaks, limited battery storage, and market constraints, with WEIM participation and demand response programs proposed to balance supply-demand and reduce wasted solar and wind generation.

 

Key Points

It is the deliberate reduction of solar and wind output when grid limits or low demand prevent full integration.

✅ Grid congestion restricts transmission capacity

✅ Midday solar peaks exceed demand, causing surplus

✅ Storage, WEIM, and demand response mitigate curtailment

 

California has long been a leader in renewable energy adoption, achieving a near-100% renewable milestone in recent years, particularly in solar and wind power. However, as the state continues to expand its renewable energy capacity, it faces a growing challenge: the curtailment of excess solar and wind energy. Curtailment refers to the deliberate reduction of power output from renewable sources when the supply exceeds demand or when the grid cannot accommodate the additional electricity.

Increasing Curtailment Trends

Recent data from the U.S. Energy Information Administration (EIA) highlights a concerning upward trend in curtailments in California. In 2024, the state curtailed a total of 3,102 gigawatt-hours (GWh) of electricity generated from solar and wind sources, surpassing the 2023 total of 2,660 GWh. This represents a 32.4% increase from the previous year. Specifically, 2,892 GWh were from solar, and 210 GWh were from wind, marking increases of 31.2% and 51.1%, respectively, compared to the first nine months of 2023.

Causes of Increased Curtailment

Several factors contribute to the rising levels of curtailment:

  1. Grid Congestion: California's transmission infrastructure has struggled to keep pace with the rapid growth of renewable energy sources. This congestion limits the ability to transport electricity from generation sites to demand centers, leading to curtailment.

  2. Midday Solar Peaks: Amid California's solar boom, solar energy production typically peaks during the midday when electricity demand is lower. This mismatch between supply and demand results in excess energy that cannot be utilized, necessitating curtailment.

  3. Limited Energy Storage: While battery storage technologies are advancing, California's current storage capacity is insufficient to absorb and store excess renewable energy for later use. This limitation exacerbates curtailment issues.

  4. Regulatory and Market Constraints: Existing market structures and regulatory frameworks may not fully accommodate the rapid influx of renewable energy, leading to inefficiencies and increased curtailment.

Economic and Environmental Implications

Curtailment has significant economic and environmental consequences. For renewable energy producers, curtailed energy represents lost revenue and undermines the economic viability of new projects. Environmentally, curtailment means that clean, renewable energy is wasted, and the grid may rely more heavily on fossil fuels to meet demand, counteracting the benefits of renewable energy adoption.

Mitigation Strategies

To address the rising curtailment levels, California is exploring several strategies aligned with broader decarbonization goals across the U.S.:

  • Grid Modernization: Investing in and upgrading transmission infrastructure to alleviate congestion and improve the integration of renewable energy sources.

  • Energy Storage Expansion: Increasing the deployment of battery storage systems to store excess energy during peak production times and release it during periods of high demand.

  • Market Reforms: Participating in the Western Energy Imbalance Market (WEIM), a real-time energy market that allows for the balancing of supply and demand across a broader region, helping to reduce curtailment.

  • Demand Response Programs: Implementing programs that encourage consumers to adjust their energy usage patterns, such as shifting electricity use to times when renewable energy is abundant.

Looking Ahead

As California continues to expand its renewable energy capacity, addressing curtailment will be crucial to ensuring the effectiveness and sustainability of its energy transition. By investing in grid infrastructure, energy storage, and market reforms, the state can reduce curtailment levels and make better use of its renewable energy resources, while managing challenges like wildfire smoke impacts on solar output. These efforts will not only enhance the economic viability of renewable energy projects but also contribute to California's 100% clean energy targets by maximizing the use of clean energy and reducing reliance on fossil fuels.

While California's renewable energy sector faces challenges related to curtailment, proactive measures and strategic investments can mitigate these issues, as scientists continue to improve solar and wind power through innovation, paving the way for a more sustainable and efficient energy future.

 

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