Unit 3 to be down for some time

By Knight Ridder Tribune


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Sixteen days after an unplanned shutdown, Browns Ferry Unit 3 remained offline and TVA was making no projections on when it would return to service.

"In this instance you had electrical equipment on the generator that is disassembled, being repaired," TVA spokes-man Gil Francis said. "It will be reassembled, and the unit will come back in service. They will do that as quickly as they can, but the No. 1 priority is to do it safely."

When operational, Unit 3 produces 1,155 megawatts of power, enough for about 650,000 homes. Because the unit is down, the Tennessee Valley Authority must find replacement power. "We've got interconnections to the marketplace to buy replacement power if needed, particularly when it's cheaper," Francis said.

"Or we can use other resources, whether it's combustion turbine, other coal plants, hydro plants, Raccoon Mountain. It's such a large system we have that flexibility."

Raccoon Mountain is an energy storage facility near Chattanooga. TVA pumps water to an elevated pool during non-peak hours, then releases the water to generate hydroelectric power during hours of peak demand. Unit 3 automatically shut down Dec. 31 when the main turbine generator received a load reject signal of unknown cause. All safety systems responded properly to the signal. A load reject signal causes the system to "think" that the generator has lost the attached load.

It is similar to the tires of a speeding vehicle losing contact with the road. With the load gone, there is a risk that the engine will overaccelerate, damaging the engine. Similarly, if TVA's safety systems failed, a false load reject signal could cause the turbine and attached generator to speed up to dangerous levels.

The repairs, according to one TVA spokesman, are focused on Unit 3's exciter. The exciter provides a source of direct current to the generator, which allows the generator to produce alternating current electricity. The alternating current electricity connects to the power grid through an output circuit breaker.

Shutdowns during August forced TVA to purchase high-priced power produced by natural gas turbines, but Francis said a January shutdown is unlikely to impact rates.

Power purchases in January are generally less expensive than in August because most systems are not running at full capacity. Francis said TVA does not keep statistics indicating how the length of the Unit 3 outage compares to other unplanned outages in TVA history.

"There is no list of unplanned outages where I can just pull it," he said. "Each outage is different." He said TVA uses unplanned outages to perform maintenance unrelated to the reason for the outage.

"You manage that outage to the best of your ability to take care of all the other issues that are pending," Francis said.

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Maritime Electric team works on cleanup in Turks and Caicos

Maritime Electric Hurricane Irma Response details utility crews aiding Turks and Caicos with power restoration, storm recovery, debris removal, and essential services, coordinated with Fortis Inc., despite limited equipment, heat, and over 1,000 downed poles.

 

Key Points

A utility mission restoring power and essential services in Turks and Caicos after Irma, led by Maritime Electric.

✅ Over 1,000 poles down; crews climbing without bucket trucks

✅ Restoring hospitals, water, and communications first

✅ Fortis Inc. coordination; 2-3 week deployment with follow-on crews

 

Maritime Electric has sent a crew to help in the clean up and power restoration of Turks and Caicos after the Caribbean island was hit by Hurricane Irma, a storm that also saw FPL's massive response across Florida.

They arrived earlier this week and are working on removing debris and equipment so when supplies arrive, power can be brought back online, and similar mutual aid deployments, including Canadian crews to Florida, have been underway as well.

Fortis Inc., the parent company for Maritime Electric operates a utility in Turks and Caicos.

Kim Griffin, spokesperson for Maritime Electric, said there are over 1000 poles that were brought down by the storm, mirroring Florida restoration timelines reported elsewhere.

"It's really an intense storm recovery," she said. 'Good spirits'

The crew is working with less heavy equipment than they are used to, climbing poles instead of using bucket trucks, in hot and humid weather.

Griffin said their focus is getting essential services restored as quckly as possible, similar to progress in Puerto Rico's restoration efforts following recent hurricanes.

The crew will be there for two or three weeks and Griffin said Maritime Electric may send another group, as seen with Ontario's deployment to Florida, to continue the job.

She said the team has been well received and is in "good spirits."

"The people around them have been very positive that they're there," she said.

"They've said it's just been overwhelming how kind and generous the people have been to them."

 

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Tornadoes and More: What Spring Can Bring to the Power Grid

Spring Storm Grid Risks highlight tornado outbreaks, flooding, power outages, and transmission disruptions, with NOAA flood outlooks, coal and barge delays, vulnerable nuclear sites, and distribution line damage demanding resilience, reliability, and emergency preparedness.

 

Key Points

Spring Storm Grid Risks show how tornadoes and floods disrupt power systems, fuel transport, and plants guide resilience.

✅ Tornado outbreaks and derechos damage distribution and transmission

✅ Flooding drives outages via treefall, substation and plant inundation

✅ Fuel logistics disrupted: rail coal, river barges, road access

 

The storm and tornado outbreak that recently barreled through the US Midwest, South and Mid-Atlantic was a devastating reminder of how much danger spring can deliver, despite it being the “milder” season compared to summer and winter.  

Danger season is approaching, and the country is starting to see the impacts. 

The event killed at least 32 people across seven states. The National Weather Service is still tallying up the number of confirmed tornadoes, which has already passed 100. Communities coping with tragedy are assessing the damage, which so far includes at least 72 destroyed homes in one Tennessee county alone, and dozens more homes elsewhere. 

On Saturday, April 1–the day after the storm struck–there were 1.1 million US utility customers without power, even as EIA reported a January power generation surge earlier in the year. On Monday morning, April 3, there were still more than 80,000 customers in the dark, according to PowerOutage.us. The storm system brought disruptions to both distribution grids–those networks of local power lines you generally see running overhead to buildings–as well as the larger transmission grid in the Midwest, which is far less common than distribution-level issues. 

While we don’t yet have a lot of granular details about this latest storm’s grid impacts, recent shifts in demand like New York City's pandemic power patterns show how operating conditions evolve, and it’s worth going through what else the country might be in for this spring, as well as in future springs. Moreover, there are steps policymakers can take to prepare for these spring weather phenomena and bolster the reliability and resilience of the US power system. 

Heightened flood risk 
The National Oceanic Atmospheric Administration (NOAA) said in a recent outlook that about 44 percent of the United States is at risk of floods this spring, equating to about 146 million people. This includes most of the eastern half of the country, the federal agency said. 

The agency also sees “major” flood risk potential in some parts of the Upper Mississippi River Basin, and relatively higher risk in the Sierra Nevada region, due in part to a historic snowpack in California.  

Multiple components of the power system can be affected by spring floods. 

Power lines – Floods can saturate soil and make trees more likely to uproot and fall onto power lines. This has been contributing to power outages during California’s recent heavy storms–called atmospheric rivers–that started over the winter. In other regions, soil moisture has even been used as a predictor of where power outages will occur due to hurricanes, so that utility companies are better prepared to send line repair crews to the right areas. Hurricanes are primarily a summer and fall phenomenon, and summer also brings grid stress from air conditioning demand in many states, so for now, during spring, they are less of a concern.  

Fuel transport – Spring floods can hinder the transportation of fuels like coal. While it is a heavily polluting fossil fuel that is set to continue declining as a fuel source for US electricity generation, with the EIA summer outlook for wind and solar pointing to further shifts, coal still accounted for roughly 20 percent of the country’s generation in 2022.   

About 70 percent of US coal is transported at least part of the way by trains. The rail infrastructure to transport coal from the Powder River Basin in Montana and Wyoming–the country’s primary coal source–was proven to be vulnerable to extreme floods in the spring of 2011, and even more extreme floods in the spring of 2019. The 2019 floods’ disruptions of coal shipments to power plants via rail persisted for months and into the summertime, also affecting river shipments of coal by barge. In June 2019, hundreds of barges were stalled in the Mississippi River, through which millions of tons of the fossil fuel are normally transported. 

Power plants – Power plants themselves can also be at risk of flooding, since most of them are sited near a source of water that is used to create steam to spin the plants’ turbines, and conversely, low water levels can constrain hydropower as seen in Western Canada hydropower drought during recent reservoir shortfalls. Most US fossil fuel generating capacity from sources like methane gas, which recently set natural gas power records across the grid, and coal utilizes steam to generate electricity. 

However, much of the attention paid to the flood risk of power plant sites has centered on nuclear plants, a key source of low-carbon electricity discussed in IAEA low-carbon electricity lessons that also require a water source for the creation of steam, as well as for keeping the plant cool in an emergency. To name a notable flood example here in the United States–both visually and substantively–in 2011, the Fort Calhoun nuclear plant in Nebraska was completely surrounded by water due to late-spring flooding along the Missouri River. This sparked a lot of concerns because it was just a few months after the March 2011 meltdown of the Fukushima Daiichi nuclear plant in Japan. The public was thankfully not harmed by the Nebraska incident, but this was unfortunately not an isolated incident in terms of flood risks posed to the US nuclear power fleet. 

 

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TransAlta brings online 119 MW of wind power in US

TransAlta Renewables US wind farms achieved commercial operation, adding 119 MW of wind energy capacity in Pennsylvania and New Hampshire, backed by PPAs with Microsoft, Partners Healthcare, and NHEC, and supported by tax equity financing.

 

Key Points

Two US wind projects totaling 119 MW, now online under PPAs and supported by tax equity financing.

✅ 119 MW online in Pennsylvania and New Hampshire

✅ PPAs with Microsoft, Partners Healthcare, and NHEC

✅ About USD 126 million raised via tax equity

 

TransAlta Renewables Inc says two US wind farms, with a total capacity of 119 MW and operated by its parent TransAlta Corp, became operational in December, amid broader build-outs such as Enel's 450-MW U.S. project coming online and, in Canada, Acciona's 280-MW Alberta wind farm advancing as well.

The 90-MW Big Level wind park in Pennsylvania started commercial operation on December 19. It sells power to technology giant Microsoft Corporation under a 15-year contract, reflecting big-tech procurement alongside Amazon's clean energy projects in multiple markets.

The 29-MW Antrim wind facility in New Hampshire is operational since December 24. It is selling power under 20-year contracts with Boston-based non-profit hospital and physicians network Partners Healthcare and New Hampshire Electric Co-op, mirroring East Coast activity at Amazon Wind Farm US East now fully operational.

The Canadian renewable power producer, which has economic interest in the two wind parks, said that upon their reaching commercial operations, it raised about USD 126 million (EUR 113m) of tax equity to partially fund the projects, as mega-deployments like Invenergy and GE's record North American project and capital plans such as a $200 million Alberta build by a Buffett-linked company underscore financing momentum.

"We continue to pursue additional growth opportunities, including potential drop-down transactions with TransAlta Corp," TransAlta Renewables president John Kousinioris commented.

The comment comes as TransAlta scrapped an Alberta wind project amid Alberta policy shifts.

 

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The Cool Way Scientists Turned Falling Raindrops Into Electricity

Raindrop Triboelectric Energy Harvesting converts falling water into electricity using Teflon (PTFE) on indium tin oxide and an aluminum electrode, forming a transient water bridge; a low frequency nanogenerator for renewable, static electricity harvesting.

 

Key Points

A method using PTFE, ITO, and an aluminum electrode to turn raindrop impacts into low frequency electrical power.

✅ PTFE on ITO boosts charge transfer efficiency.

✅ Water bridge links electrodes for rapid discharge.

✅ Low frequency output suits continuous energy harvesting.

 

Scientists at the City University of Hong Kong have used a Teflon-coated surface and a phenomenon called triboelectricity to generate a charge from raindrops. “Here we develop a device to harvest energy from impinging water droplets by using an architecture that comprises a polytetrafluoroethylene [Teflon] film on an indium tin oxide substrate plus an aluminium electrode,” they explain in their new paper in Nature as a step toward cheap, abundant electricity in the long term.

Triboelectricity itself is an old concept. The word means “friction electricity”—from the Greek tribo, to rub or wear down, which is why a diatribe tires you out—and dates back a long, long time. Static electricity is the most famous kind of triboelectric, and related work has shown electricity from the night sky can be harvested as well in niche setups. In most naturally occurring kinds, scientists have studied triboelectric in order to avoid its effects, like explosions inside of grain silos or hospital workers touching off pure oxygen. (Blowing sand causes an electric field, and NASA even worries about static when astronauts eventually land on Mars.)

One of the most studied forms of intentional and useful triboelectric is in systems such as ocean wave generators where the natural friction of waves meets nanogenerators of triboelectric energy. These even already use Teflon, which has natural conductivity that makes it ideal for this job. But triboelectricity is chaotic, and harnessing it generally involves a bunch of complicated, intersecting variables that can vary with the hourly weather. Promises of static electricity charging devices have often been, well, so much hot, sandy wind.

The scientists at City University of Hong Kong used triboelectric ideas to turn falling raindrops into energy. They say previous versions of the same idea were not very efficient, with materials that didn’t allow for high-fidelity transfer of electrical charge. (Many sources of renewable energy aren’t yet as efficient to turn into power, both because of developing technology and because their renewability means even less efficient use could be better than, for example, fossil fuels, and advances in renewable energy storage could help.)

“[A]chieving a high density of electrical power generation is challenging,” the team explains in its paper. “Traditional hydraulic power generation mainly uses electromagnetic generators that are heavy, bulky, and become inefficient with low water supply.” Diversifying how power is generated by water sources such as oceans and rivers is good for the existing infrastructure as well as new installations.

The research team found that as simulated raindrops fell on their device, the way the water accumulated and spread created a link between their two electrodes, one Teflon-coated and the other aluminum. This watery de facto wire link closes the loop and allows accumulated energy to move through the system. Because it’s a mechanical setup, it’s not limited to salty seawater, and because the medium is already water, its potential isn’t affected by ambient humidity either.

Raindrop energy is very low frequency, which means this tech joins many other existing pushes to harvest continuously available, low frequency natural energy, including underwater 'kites' that exploit steady currents. To make an interface that increases “instantaneous power density by several orders of magnitude over equivalent devices,” as the researchers say they’ve done here, could represent a major step toward feasibility in triboelectric generation.

 

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Taiwan's economic minister resigns over widespread power outage

Taiwan Power Blackout disrupts Taipei and commercial hubs after a Taoyuan natural gas plant error, triggering nationwide outage, grid failure, elevator rescues, power rationing, and the economic minister's resignation, as CPC Corporation restores supply.

 

Key Points

A nationwide Taiwan outage from human error at a Taoyuan gas plant, triggering rationing and a minister's resignation.

✅ Human error disrupted natural gas supply at Taoyuan plant

✅ 6.68 million users affected; grid failure across cities

✅ Minister Lee resigned; President Tsai ordered a review

 

Taiwan's economic minister resigned after power was knocked out in many parts of Taiwan, with regional parallels such as China power cuts highlighting grid vulnerabilities, including capital Taipei's business and high-end shopping district, due to an apparent "human error" at a key power plant.

Economic Affairs minister Lee Chih-kung tendered his resignation verbally to Premier Lin Chuan, United Daily News reported, citing a Cabinet spokesman. Lin accepted the resignation, the spokesman said according to the daily.

As many as 6.68 million households and commercial units saw their power supply cut or disrupted on Tuesday after "human error" disrupted natural gas supply at a power plant in northern Taiwan's Taoyuan, the semi-official Central News Agency reported, citing the government-controlled oil company CPC Corporation as saying.

The company added that power at the plant, Taiwan's biggest natural gas power plant, resumed two minutes later.

In New Taipei City, there were at least 27,000 reported cases of people being stuck in lifts. Photos in social media also showed huge crowds stranded in lift lobby in Taipei's iconic 101-storey Taipei 101 building.

Power rationing was implemented beginning 6pm, and, as seen in the National Grid short supply warning in other markets, such steps aim to stabilize supply, Central News Agency said. Power supply was gradually being restored beginning at about 9:40pm. news reports said.

President Tsai Ing-wen apologised for the blackout, noting parallels with Japan's near-blackouts that underscored grid resilience, and said that she has ordered all relevant departments to produce clear report in the shortest time possible.

"Electricity is not just a problem about people's livelihoods but also a national security issue. A comprehensive review must be carried out to find out how the electric power system can be so easily paralysed by human error," said Ms Tsai in a Facebook post.

Taiwan has been at risk of a power shortage after a recent typhoon knocked down a power transmission tower in Hualien county along the eastern coast of Taiwan, rather than a demand-driven slowdown like the China power demand drop during pandemic factory shutdowns. This reduced the electricity supply by 1.3million kilowatts, or about 4 per cent of the operating reserve.

That was followed by the breakdown of a power generator at Taiwan's largest power plant, which further reduced the operating reserve by 1.5 per cent.

The situation is worsened by the ongoing heatwave that has hit Taiwan, with temperatures soaring to 38 degrees Celsius over the past week.

As a result, the government had imposed the rationing of electricity, and, highlighting how regional strains such as China's power woes can ripple into global markets, switched off all air-conditioning in many of its Taipei offices, a move that drew some public backlash.

 

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Ontario Businesses To See Full Impact of 2021 Electricity Rate Reductions

Ontario Comprehensive Electricity Plan delivers Global Adjustment reductions for industrial and commercial non-RPP customers, lowering electricity rates, shifting renewable energy costs, and enhancing competitiveness across Ontario businesses in 2022, with additional 4 percent savings.

 

Key Points

Ontario's plan lowers Global Adjustment by shifting renewable costs, cutting industrial and commercial bills 15-17%.

✅ Shifts above-market non-hydro renewable costs to the Province

✅ Reduces GA for industrial and commercial non-RPP customers

✅ Additional 4% savings on 2022 bills after GA deferral

 

As of January 1, 2022, industrial and commercial electricity customers will benefit from the full savings introduced through the Ontario government’s Comprehensive Electricity Plan, which supports stable electricity pricing for industrial and commercial companies, announced in Budget 2020, and first implemented in January 2021. This year customers could see an additional four percent savings compared to their bills last year, bringing the full savings from the Comprehensive Electricity Plan to between 15 and 17 per cent, making Ontario a more competitive place to do business.

“Our Comprehensive Electricity Plan has helped reverse the trend of skyrocketing electricity prices that drove jobs out of Ontario,” said Todd Smith, Minister of Energy. “Over 50,000 customers are benefiting from our government’s plan which has reduced electricity rates on clean and reliable power, allowing them to focus on reinvesting in their operations and creating jobs here at home.”

Starting on January 1, 2021, the Comprehensive Electricity Plan reduced overall Global Adjustment (GA) costs for industrial and commercial customers who do not participate in the Regulated Price Plan (RPP) by shifting the forecast above-market costs of non-hydro renewable energy, such as wind, solar and bioenergy, from the rate base to the Province, alongside energy-efficiency programs that complement demand reduction efforts.

“Since taking office, our government has listened to job creators and worked to lower the costs of doing business in the province. Through these significant reductions in electricity prices through the Comprehensive Electricity Plan, customers all across Ontario will benefit from significant savings in their business operations in 2022,” said Vic Fedeli, Minister of Economic Development, Job Creation and Trade. “By continuing to reduce electricity costs, lowering taxes, and cutting red tape our government has reduced the cost of doing business in Ontario by nearly $7 billion annually to ensure that we remain competitive, innovative and poised for economic recovery.”

As part of its COVID response, including electricity relief for families and small businesses, Ontario had deferred a portion of GA between April and June 2020 for industrial and non-RPP commercial customers, with more than 50,000 customers benefiting. Those same businesses paid back these deferred GA costs over 12 months, between January 2021 and December 2021, while the province prepared to extend disconnect moratoriums for residential customers.

During the pandemic, residential electricity use rose even as overall consumption dropped, underscoring shifts in load patterns.

Now that the GA deferral repayment period is over, industrial and non-RPP commercial customers will benefit from the full cost reductions provided to them by the Comprehensive Electricity Plan, alongside temporary off-peak rate relief that supported families and small businesses. This means that, beginning January 1, 2022, these businesses could see an additional four per cent savings on their bills compared to 2021, as new ultra-low overnight pricing options emerge depending on their location and consumption.

 

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