Condenser leaks reduce power at reactor

By Columbus Republic


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Dominion Virginia Power has reduced power in a reactor at its North Anna plant so crews can repair leaks in a water-condensing unit.

Dominion spokesman Richard Zuercher told The Richmond Times-Dispatch that the utility expects to return the Unit 2 reactor to full power soon.

Zuercher says Unit 2 was reduced to 84 percent capacity after the leaks were discovered January 6.

North Anna's other reactor, Unit 1, has continued to operate at full power.

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Climate Solution: Use Carbon Dioxide to Generate Electricity

Methane Hydrate CO2 Sequestration uses carbon capture and nitrogen injection to swap gases in seafloor hydrates along the Gulf of Mexico, releasing methane for electricity while storing CO2, according to new simulation research.

 

Key Points

A method injecting CO2 and nitrogen into hydrates to store CO2 while releasing methane for power.

✅ Nitrogen aids CO2-methane swap in hydrate cages, speeding sequestration

✅ Gulf Coast proximity to emitters lowers transport and power costs

✅ Revenue from methane electricity could offset carbon capture

 

The world is quickly realizing it may need to actively pull carbon dioxide out of the atmosphere to stave off the ill effects of climate change. Scientists and engineers have proposed various carbon capture techniques, but most would be extremely expensive—without generating any revenue. No one wants to foot the bill.

One method explored in the past decade might now be a step closer to becoming practical, as a result of a new computer simulation study. The process would involve pumping airborne CO2 down into methane hydrates—large deposits of icy water and methane right under the seafloor, beneath water 500 to 1,000 feet deep—where the gas would be permanently stored, or sequestered. The incoming CO2 would push out the methane, which would be piped to the surface and burned to generate electricity, whether sold locally or via exporters like Hydro-Que9bec to help defray costs, to power the sequestration operation or to bring in revenue to pay for it.

Many methane hydrate deposits exist along the Gulf of Mexico shore and other coastlines. Large power plants and industrial facilities that emit CO2 also line the Gulf Coast, where EPA power plant rules could shape deployment, so one option would be to capture the gas directly from nearby smokestacks, keeping it out of the atmosphere to begin with. And the plants and industries themselves could provide a ready market for the electricity generated.

A methane hydrate is a deposit of frozen, latticelike water molecules. The loose network has many empty, molecular-size pores, or “cages,” that can trap methane molecules rising through cracks in the rock below. The computer simulation shows that pushing out the methane with CO2 is greatly enhanced if a high concentration of nitrogen is also injected, and that the gas swap is a two-step process. (Nitrogen is readily available anywhere, because it makes up 78 percent of the earth’s atmosphere.) In one step the nitrogen enters the cages; this destabilizes the trapped methane, which escapes the cages. In a separate step, the nitrogen helps CO2 crystallize in the emptied cages. The disturbed system “tries to reach a new equilibrium; the balance goes to more CO2 and less methane,” says Kris Darnell, who led the study, published June 27 in the journal Water Resources Research. Darnell recently joined the petroleum engineering software company Novi Labs as a data scientist, after receiving his Ph.D. in geoscience from the University of Texas, where the study was done.

A group of labs, universities and companies had tested the technique in a limited feasibility trial in 2012 on Alaska’s North Slope, where methane hydrates form in sandstone under deep permafrost. They sent CO2 and nitrogen down a pipe into the hydrate. Some CO2 ended up being stored, and some methane was released up the same pipe. That is as far as the experiment was intended to go. “It’s good that Kris [Darnell] could make headway” from that experience, says Ray Boswell at the U.S. Department of Energy’s National Energy Technology Laboratory, who was one of the Alaska experiment leaders but was not involved in the new study. The new simulation also showed that the swap of CO2 for methane is likely to be much more extensive—and to happen quicker—if CO2 enters at one end of a hydrate deposit and methane is collected at a distant end.

The technique is somewhat similar in concept to one investigated in the early 2010s by Steven Bryant and others at the University of Texas. In addition to numerous methane hydrate deposits, the Gulf Coast has large pools of hot, salty brine in sedimentary rock under the coastline. In this system, pumps would send CO2 down into one end of a deposit, which would force brine into a pipe that is placed at the other end and leads back to the surface. There the hot brine would flow through a heat exchanger, where heat could be extracted and used for industrial processes or to generate electricity, supporting projects such as electrified LNG in some markets. The upwelling brine also contains some methane that could be siphoned off and burned. The CO2 dissolves into the underground brine, becomes dense and sinks further belowground, where it theoretically remains.

Either system faces big practical challenges, and building shared CO2 storage hubs to aggregate captured gas is still evolving. One is creating a concentrated flow of CO2; the gas makes up only .04 percent of air, and roughly 10 percent of the smokestack emission from a typical power plant or industrial facility. If an efficient methane hydrate or brine system requires an input that is 90 percent CO2, for example, concentrating the gas will require an enormous amount of energy—making the process very expensive. “But if you only need a 50 percent concentration, that could be more attractive,” says Bryant, who is now a professor of chemical and petroleum engineering at the University of Calgary. “You have to reduce the [CO2] capture cost.”

Another major challenge for the methane hydrate approach is how to collect the freed methane, which could simply seep out of the deposit through numerous cracks and in all directions. “What kind of well [and pipe] structure would you use to grab it?” Bryant asks.

Given these realities, there is little economic incentive today to use methane hydrates for sequestering CO2. But as concentrations rise in the atmosphere and the planet warms further, and as calls for an electric planet intensify, systems that could capture the gas and also provide energy or revenue to run the process might become more viable than techniques that simply pull CO2 from the air and lock it away, offering nothing in return.

 

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Warning: Manitoba Hydro can't service new 'energy intensive' customers

Manitoba Hydro capacity constraints challenge clean energy growth as industrial demand, hydrogen projects, EV batteries, and electrification strain the grid; limited surplus, renewables, storage, and transmission bottlenecks hinder new high-load connections.

 

Key Points

Limited surplus power blocks new energy-intensive loads until added generation and transmission expand Manitoba's grid.

✅ No firm commitments for new energy-intensive industrial customers

✅ Single large load could consume remaining surplus capacity

✅ New renewables need transmission; gas, nuclear face trade-offs

 

Manitoba Hydro lacks the capacity to provide electricity to any new "energy intensive" industrial customers, the Crown corporation warns in a confidential briefing note that undercuts the idea this province can lure large businesses with an ample supply of clean, green energy, as the need for new power generation looms for the utility.

On July 28, provincial economic development officials unveiled an "energy roadmap" that said Manitoba Hydro must double or triple its generating capacity, as electrical demand could double over the next two decades in order to meet industrial and consumer demand for electricity produced without burning fossil fuels.

Those officials said 18 potential new customers with high energy needs were looking at setting up operations in Manitoba — and warned the province must be careful to choose businesses that provide the greatest economic benefit as well as the lowest environmental impact.

In a briefing note dated Sept. 13, obtained by CBC News, Manitoba Hydro warns it doesn't have enough excess power to hook up any of these new heavy electricity-using customers to the provincial power grid.

There are actually 57 proposals to use large volumes of electricity, Hydro says in the note, including eight projects already in the detailed study phase and nine where the proponents are working on construction agreements.

"Manitoba Hydro is unable to offer firm commitments to prospective customers that may align with Manitoba's energy roadmap and/or provincial economic development objectives," Hydro warns in the note, explaining it is legally obliged to serve all existing customers who need more electricity.

"As such, Manitoba Hydro cannot reserve electric supply for particular projects."

Hydro says in the note its "near-term surplus electricity supply" is so limited amid a Western Canada drought that "a single energy-intensive connection may consume all remaining electrical capacity."

Adding more electrical generating capacity won't be easy, even with new turbine investments underway, and will not happen in time to meet demands from customers looking to set up shop in the province, Hydro warns.

The Crown corporation goes on to say it's grappling with numerous requests from existing and prospective energy-intensive customers, mainly for producing hydrogen, manufacturing electric vehicle batteries and switching from fossil fuels to electricity, such as to use electricity for heat in buildings.

In a statement, Hydro said it wants to ensure Manitobans know the corporation is not running out of power — just the ability to meet the needs of large new customers, and continues to provide clean energy to neighboring provinces today.

"The size of loads looking to come to Manitoba are significantly larger than we typically see, and until additional supply is available, that limits our ability to connect them," Hydro spokesperson Bruce Owen said in a statement.

Adding wind power or battery storage, for example, would require the construction of more transmission lines, and deals such as SaskPower's purchase depend on that interprovincial infrastructure as well.

Natural gas plants are relatively inexpensive to build but do not align with efforts to reduce carbon emissions. Nuclear power plants require at least a decade of lead time to build, and tend to generate local opposition.

Hydro has also ruled out building another hydroelectric dam on the Nelson River, where the Conawapa project was put on hold in 2014.

 

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Sub-Saharan Africa has a huge electricity problem - but with challenge comes opportunity

Sub-Saharan Africa Energy Access faces critical deficits; SDG7, clean energy finance, off-grid solar, and microgrids drive electrification for health, education, and economy amid World Bank and IEA efforts to expand reliable, affordable power.

 

Key Points

Reliable, affordable power in sub-Saharan Africa via renewables, off-grid solar, and SDG7-led electrification.

✅ SDG7 targets universal, modern energy access by 2030

✅ Off-grid solar and microgrids boost rural electrification

✅ Health, education, and business depend on reliable power

 

Sub-Saharan Africa has an electricity problem. While the world as a whole has made great strides when it comes to providing access to electricity and moving toward universal electricity access worldwide (the world average is now 90 per cent with access, up from 83 per cent in 2010), southern and western African states still lag far behind.

According to Tracking SDG7: The Energy Progress Report, produced by a consortium of organisations including the World Bank, the International Energy Agency and the World Health Organization, 759 million people were without electricity in 2019 and threequarters of them were based in sub-Saharan Africa. At just seven per cent, South Sudan had the lowest access figures; Chad, Burundi and Malawi were only marginally higher. What’s more, due to a combination of factors, the situation is getting worse. In total, the region’s access deficit increased from 556 million people in 2010 to 570 million people in 2019.

These days, being without electricity has an impact on every sphere of life. The Covid-19 pandemic only served to put this into sharper relief. Intermittent electricity meant vaccination doses that rely on cold storage were impossible to deliver and, as more than 70 per cent of the health facilities in sub-Saharan Africa have no access to reliable electricity, the problem was vast. But even without a global pandemic, having no power stymies opportunity in every field, from education to economics.

French photojournalist Pascal Maitre, who has spent much of his career writing about sub-Saharan Africa, wanted to document the problems faced by people in areas with no electricity. He thought particularly carefully about the location for his project. ‘First, I was thinking I could take images in the Democratic Republic of the Congo,’ he says. ‘But then I thought that if you chose a place that has war, it’s logical that electricity won’t really work. So, instead, I wanted to find a place that is quite stable. I decided to go to Benin, where they have a democracy. It is a good example of a country that’s not in really bad shape but where they still have this problem. Also, I didn’t want to go to a place that is very remote, where it is normal not to have good service. So I decided to go to a place around 50 kilometres from the capital that you can get to by road.’

Maitre visited several villages in the region, as well as making trips to Chad and Senegal, and encountered the full range of limitations engendered by the power shortage. From teachers struggling to conduct lessons in the dark to midwives forced to work with only the weak light from a phone, the situation was clearly unacceptable. ‘People were very, very, very upset,’ he says. ‘I conducted a lot of interviews in different villages and lack of electricity touches education, economy, business, security and also emigration, because people have to move to big cities or maybe to Europe to get jobs.’

Where once the situation might have been accepted as the norm, people today are fully aware of the ways in which they are held back by the lack of power. As Maitre remembers: ‘A guy said to me one day, “Do you think it is normal that last time my wife delivered a baby, the midwife had to hold her phone between her teeth in order to see what she was doing?” You feel very frustrated.’ He adds that the fact that most people now have mobile phones only highlights the hardship. ‘Before, maybe it was not so frustrating. But now, most of these people have cellphones. The cellphone company puts antennae everywhere so the phones work, but people cannot recharge their phones. They have to go to the market, where someone will come with a generator to recharge.’

Governments and global organisations are very aware of the problem across the world as a whole. Sustainable Development Goal 7 (SDG7) – one of the 17 goals set out in 2015 by the United Nations General Assembly – was designed to ensure universal access to affordable, reliable, sustainable and modern energy by 2030, underscoring the push for clean, affordable and sustainable electricity for all by 2030. As part of this goal, international financial flows to developing countries in support of clean energy reached US$17 billion in 2018. As a result, some areas have seen huge improvement. According to the Energy Progress Report, in Latin America and the Caribbean, and in Eastern and South-Eastern Asia, the advance of electrification has been enough to approach universal access. By 2019, in Western Asia and North Africa, and Central and South Asia, 94 and 95 per cent of the population respectively had access to electricity.

But these statistics only serve to emphasise just how bad the situation is in sub-Saharan Africa, where electricity systems are unlikely to go green this decade according to several analyses. As the report states: ‘While renewable energy has demonstrated remarkable resilience during the pandemic, the unfortunate fact is that gains in energy access throughout Africa are being reversed: the number of people lacking access to electricity is set to increase in 2020, making basic electricity services unaffordable for up to 30 million people who had previously enjoyed access.’

The small silver lining is that if the situation is dealt with properly, the region could build a renewable-energy system from the ground up, rather than having to undergo the costly and complex transitions underway in developed countries. In rural areas, small-scale or off-grid renewable systems (mostly solar) are expected to play an important role, as highlighted by a recent IRENA report on decarbonisation, in increasing access. In fact, solar panels are already used in many areas. In 2019, 105 million people had access to off-grid solar solutions, up from 85 million in 2016, and almost half lived in sub-Saharan Africa, with 17 million in Kenya and eight million in Ethiopia.

Rachel Kyte is currently serving as the 14th dean of the Fletcher School at Tufts University in the USA, but her CV is long. She was previously CEO of the UN-affiliated Sustainable Energy for All (SeforALL), as well as the World Bank Group vice president and special envoy for climate change, leading the run-up to the Paris Agreement. According to her, a focus on renewables is absolutely essential, both for wider efforts to tackle climate change, with some advocating a fossil fuel lockdown to drive a climate revolution, but also for the people of sub-Saharan Africa. ‘The fossil fuel industry has said it will just extend the centralised fossil-fuel power systems that we have today to reach these people,’ she says.

 

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Duke solar solicitation nearly 6x over-subscribed

Duke Energy Carolinas Solar RFP draws 3.9 GW of utility-scale bids, oversubscribed in DEP and DEC, below avoided cost rates, minimal battery storage, strict PPA terms, and interconnection challenges across North and South Carolina.

 

Key Points

Utility-scale solar procurement in DEC and DEP, evaluated against avoided cost, with few storage bids and PPA terms.

✅ 3.9 GW bids for 680 MW; DEP most oversubscribed

✅ Most projects 7-80 MWac; few include battery storage

✅ Bids must price below 20-year avoided cost estimate

 

Last week the independent administrator for Duke’s 680 MW solar solicitation revealed data about the projects which have bid in response to the offer, showing a massive amount of interest in the opportunity.

Overall, 18 individuals submitted bids for projects in Duke Energy Carolinas (DEC) territory and 10 in Duke Energy Progress (DEP), with a total of more than 3.9 GW of proposals – more nearly 6x the available volume. DEP was relatively more over-subscribed, with 1.2 GWac of projects vying for only 80 MW of available capacity.

This is despite a requirement that such projects come in below the estimate of Duke’s avoided cost for the next 20 years, and amid changes in solar compensation that could affect project economics. Individual projects varied in capacity from 7-80 MWac, with most coming within the upper portion of that range.

These bids will be evaluated in the spring of 2019, and as Duke Energy Renewables continues to expand its portfolio, Duke Energy Communications Manager Randy Wheeless says he expects the plants to come online in a year or two.

 

Lack of storage

Despite recent trends in affordable batteries, of the 78 bids that came in only four included integrated battery storage. Tyler Norris, Cypress Creek Renewables’ market lead for North Carolina, says that this reflects that the methodology used is not properly valuing storage.

“The lack of storage in these bids is a missed opportunity for the state, and it reflects a poorly designed avoided cost rate structure that improperly values storage resources, commercially unreasonable PPA provisions, and unfavorable interconnection treatment toward independent storage,” Norris told pv magazine.

“We’re hopeful that these issues will be addressed in the second RFP tranche and in the current regulatory proceedings on avoided cost and state interconnection standards and grid upgrades across the region.”

 

Limited volume for North Carolina?

Another curious feature of the bids is that nearly the same volume of solar has been proposed for South Carolina as North Carolina – despite this solicitation being in response to a North Carolina law and ongoing legal disputes such as a church solar case that challenged the state’s monopoly model.

 

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Ontario introduces new 'ultra-low' overnight hydro pricing

Ontario Ultra-Low Overnight Electricity Rates cut costs for shift workers and EV charging, with time-of-use pricing, off-peak savings, on-peak premiums, kilowatt-hour details, and Ontario Energy Board guidance for homes and businesses across participating utilities.

 

Key Points

Ontario's ultra-low overnight plan: 2.4c/kWh 11pm-7am for EVs, shift workers; higher daytime on-peak pricing.

✅ 2.4c/kWh 11pm-7am; 24c/kWh on-peak 4pm-9pm

✅ Best for EV charging, shift work, night usage

✅ Available provincewide by Nov 1 via local utilities

 

The Ontario government is introducing a new ultra-low overnight price plan that can benefit shift workers and individuals who charge electric vehicles while they sleep.

Speaking at a news conference on Tuesday, Energy Minister Todd Smith said the new plan could save customers up to $90 a year.

“Consumer preferences are still changing and our government realized there was more we could do, especially as the province continues to have an excess supply of clean electricity at night when province-wide electricity demand is lower,” Smith said, noting a trend underscored by Ottawa's demand decline during the pandemic.

The new rate, which will be available as an opt-in option as of May 1, will be 2.4 cents per kilowatt-hour from 11 p.m. to 7 a.m. Officials say this is 67 per cent lower than the current off-peak rate, which saw a off-peak relief extension during the pandemic.

However, customers should be aware that this plan will mean a higher on-peak rate, as unlike earlier calls to cut peak rates, Hydro One peak charges remained unchanged for self-isolating customers.

The new plan will be offered by Toronto Hydro, London Hydro, Centre Wellington Hydro, Hearst Power, Renfrew Hydro, Wasaga Distribution, and Sioux Lookout Hydro by May. Officials have said this will be expanded to all local distribution companies by Nov. 1.

With the new addition of the “ultra low” pricing, there are now three different electricity plans that Ontarians can choose from. Here is what you have to know about the new hydro options:

TIME OF USE:
Most residential customers, businesses and farms are eligible for these rates, similar to BC Hydro time-of-use proposals in another province, which are divided into off-peak, mid-peak and on-peak hours.

This is what customers will pay as of May 1 according to the Ontario Energy Board, following earlier COVID-19 electricity relief measures that temporarily adjusted rates:

 Off-peak (Weekdays between 7 p.m. and 7 a.m. and on weekends/holidays): 7.4 cents per kilowatt-hour
 Mid-Peak (Weekdays between 7 a.m. and 11 a.m., and between 5 p.m. and 7 p.m.): 10.2 cents per kilowatt-hour
 On-Peak ( Weekdays 11 a.m. to 5 p.m.): 15.1 cents per kilowatt-hour

TIERED RATES
This plan allows customers to get a standard rate depending on how much electricity is used. There are various thresholds per tier, and once a household exceeds that threshold, a higher price applies. Officials say this option may be beneficial for retirees who are home often during the day or those who use less electricity overall.

The tiers change depending on the season. This is what customers will pay as of May 1:

 Residential households that use 600 kilowatts of electricity per month and non-residential businesses that use 750 kilowatts per month: 8.7 cents per kilowatt-hour.
 Residences and businesses that use more than that will pay a flat rate of 10.3 cents per kilowatt-hour


ULTRA-LOW OVERNIGHT RATES
Customers can opt-in to this plan if they use most of their electricity overnight.

This is what customers will pay as of May 1:

  •  Between 11 p.m. and 7 a.m.: 2.4 cents per kilowatt-hour
  •  Weekends and holidays between 7 a.m. and 11 p.m.: 7.4 cents per kilowatt-hour
  •  Mid-Peak (Weekdays between 7 a.m. and 4 p.m., and between 9 p.m. and 11 p.m.): 10.2 cents per kilowatt-hour
  •  On-Peak (weekdays between 4 p.m. and 9 p.m.): 24 cents per kilowatt-hour

More information on these plans can be found on the Ontario Energy Board website, alongside stable pricing for industrial and commercial updates from the province.

 

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Fish boom prompts energy conglomerate to spend $14.5M to bury subsea cables

Maritime Link Cable Burial safeguards 200-kV subsea cables in the Cabot Strait as Emera and Nova Scotia Power trench lines to mitigate bottom trawling risks from a redfish boom, ensuring Muskrat Falls hydro delivery.

 

Key Points

Trenching Cabot Strait subsea power cables to prevent redfish-driven bottom trawling and ensure Muskrat Falls power.

✅ $14.492M spent trenching 59 km at 400 m depth

✅ Protects 200-kV, 170-km subsea interconnects from trawls

✅ Driven by Gulf redfish boom; DFO and UARB consultations

 

The parent company of Nova Scotia Power disclosed this week to the Utility and Review Board, amid Site C dam watchdog attention to major hydro projects, that it spent almost $14,492,000 this summer to bury its Maritime Links cables lying on the floor of the Cabot Strait between Newfoundland and Cape Breton.

It's a fish story no one saw coming, at least not Halifax-based energy conglomerate Emera.

The parent company of Nova Scotia Power disclosed this week to the Utility and Review Board that it spent almost $14,492,000 this summer to bury its Maritime Link cables lying on the floor of the Cabot Strait between Newfoundland and Cape Breton.

The cables were protected because an unprecedented explosion in the redfish population in the Gulf of St Lawrence is about to trigger a corresponding boom in bottom trawling in the area.

Also known as ocean perch, redfish were not on anyone's radar when the $1.5-billion Maritime Link was designed and built to carry Muskrat Falls hydroelectricity from Newfoundland to Nova Scotia.

The two 200-kilovolt electrical submarine cables spanning the Cabot Strait are the longest in North America, compared with projects like the New England Clean Power Link planned further south. They are each 170 kilometres long and weigh 5,500 tonnes.

Nova Scotia Power customers are paying for the Maritime Link in return for a minimum of 20 per cent of the electricity generated by Muskrat Falls over 35 years.

The electricity is supposed to start sending first electricity through the Maritime Link in mid-2020.

First time cost disclosed
In August, the company buried 59 kilometres of subsea cables one metre below the bottom at depths of 400 metres.

"These cables had not been previously trenched due to the absence of fishing activities at those depths when the cables were originally installed," spokesperson Jeff Myrick wrote in an email to CBC News in October.

Ratepayers will get the bill next year, as utilities also face risks like copper theft that can drive costs in the region. Until now, the company had declined to release costs relating to protecting the Maritime Link.

The bill will be presented to regulators, a process that has affected projects such as a Manitoba Hydro line to Minnesota, when the company applies to recover Maritime Link costs from Nova Scotia Power ratepayers in 2020.

Myrick said the company was acting after consultation with the Department of Fisheries and Oceans.

Unexpected consequences
After years of overfishing in the 1980s and early 1990s, redfish quotas were slashed and a moratorium imposed on some redfish.

Confusingly, there are actually two redfish species in the Gulf of St. Lawrence.

But very strong recent year classes, that have coincided with warming waters in the gulf, as utilities adapt to climate change considerations grow, have produced redfish in massive numbers.

After years of overfishing, the redfish population is now booming in the Gulf of St. Lawrence. (Submitted by Marine Institute)
There is now believed to be three-million tonnes of redfish in the Gulf of St Lawrence.

The Department of Fisheries and Oceans is expected to increase quotas in the coming years and the fishing industry is gearing up in a big way.

Earlier this month, Scotia Harvest announced it will begin construction of a new $14-million fish plant in Digby next spring in part to process increased redfish catches.

 

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