How Toronto kept the water flowing during blackout

By The Toronto Star


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The city of Toronto was only days away from running out of water during last August^^s blackout, but conservation efforts, including the temporary shutdown of big industrial users, eased the threat.

Mike Price, the city's general manager of water and waste- water, said yesterday that during the power outage Toronto's residents were never in any immediate danger of facing empty water pipes.

His comments came in response to a story in a recent edition of the Toronto Star that was based on federal documents obtained under the Access to Information Act.

Those documents stated that on Aug. 15, one day after the blackout began, "the city of Toronto is currently meeting its demand for water, but just barely."

Price disputed that statement, saying Toronto had enough water supplies in its reservoirs to cope for several days.

"It gave the impression that we could only last a few hours longer, whereas we assumed we were going to last a few days longer," he said.

However, Price conceded: "Eventually, if the blackout had gone on for a few more days, yes, the taps would have run dry."

On a routine basis, the city keeps enough water on hand — 90 per cent to 95 per cent capacity averaged across the 14 sites — for two days of normal, average consumption.

Once the power went out at 4:11 p.m. on Aug. 14, the city could not collect any additional water for its 10 underground water reservoirs and four water towers.

Usually, it uses massive machinery to pump water into the reservoirs and water towers, doing so at night, when power is cheaper.

Because of the high quantities of electricity that equipment demands, it would be impossible to use temporary generators.

Permanent diesel generators and mobile generators were in use at 81 sewage-pumping stations. The only problem encountered was in the east end, where two dozen homes near Ashbridge's Bay had their basements flooded with raw sewage.

Once the blackout hit, consumption dropped significantly as a result of conservation efforts and a provincial decision to order all non-essential workers to stay home.

With industry effectively shut down, the sector that consumes a third of the city's water under normal conditions wasn't using any of the limited supply.

Power was gradually restored in various parts of the city, with some areas back online within 12 hours.

The city encountered a minor glitch when a water tower in Etobicoke ran low.

But because all of the water reservoirs and towers are linked, city officials managed to redirect flow so that residents in that area never knew of the problem, Price said.

He added that Y2K preparedness efforts and previous warnings from the provincial government about potential brownouts helped make the city well prepared for the blackout.

Staff had practised for an emergency response.

In an outage, it would not be possible to pump diesel, so all tanks were moved above-ground so fuel could be poured by hand.

Councillor Case Ootes (Ward 29, Toronto-Danforth), who was deputy mayor at the time of the blackout, said there was never any danger the city would run out of water.

While the federal documents pointed to communications problems, such as some emergency numbers of federal agencies being out of service or ringing unanswered, Ootes said that, generally, the city did not encounter many problems.

"At the start, there was some difficulties in making the connection, but into the second day, the co-operation was very good," he said.

"All in all, I think the city managed on its own because it had its own resources and co-operation from Toronto Hydro."

The federal documents noted that on Aug. 15, Bolton and parts of Brampton had no water because of the blackout.

Peel Region public works director Mark Schiller said the disruption in those areas wasn't caused by a backup power failure, but stemmed from a problem unrelated to the blackout: a break in a major feeder main, which meant the line had to be shut down for repairs for half a day.

He didn't have precise figures on how long water was disrupted or how many residents were affected.

Had the 60-inch-diameter pipe not broken, residents would have had lower water pressure but probably wouldn't have lost water supply entirely, Schiller said.

Pumping capacity was reduced because of the backup power supply being used during the blackout, Schiller said. The backup system can handle the demand for water on an average winter's day, he said.

Peel spent $20 million between 1999 and 2002 on providing backup power for use in blackouts.

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California's solar energy gains go up in wildfire smoke

California Wildfire Smoke Impact on Solar reduces photovoltaic output, as particulate pollution, soot, and haze dim sunlight and foul panels, cutting utility-scale generation and grid reliability across CAISO during peak demand and heatwaves.

 

Key Points

How smoke and soot cut solar irradiance and foul panels, slashing PV generation and straining CAISO grid operations.

✅ Smoke blocks sunlight; soot deposition reduces panel efficiency.

✅ CAISO reported ~30% drop versus July during peak smoke.

✅ Longer fire seasons threaten solar reliability and capacity planning.

 

Smoke from California’s unprecedented wildfires was so bad that it cut a significant chunk of solar power production in the state, even as U.S. solar generation rose in 2022 nationwide. Solar power generation dropped off by nearly a third in early September as wildfires darkened the skies with smoke, according to the US Energy Information Administration.

Those fires create thick smoke, laden with particles that block sunlight both when they’re in the air and when they settle onto solar panels. In the first two weeks of September, soot and smoke caused solar-powered electricity generation to fall 30 percent compared to the July average, according to the California Independent System Operator (CAISO), which oversees nearly all utility-scale solar energy in California, where wind and solar curtailments have been rising amid grid constraints. It was a 13.4 percent decrease from the same period last year, even though solar capacity in the state has grown about 5 percent since September 2019.

California depends on solar installations for nearly 20 percent of its electricity generation, and has more solar capacity than the next five US states trailing it combined as it works to manage its solar boom sustainably. It will need even more renewable power to meet its goal of 100 percent clean electricity generation by 2045, building on a recent near-100% renewable milestone that underscored the transition. The state’s emphasis on solar power is part of its long-term efforts to avoid more devastating effects of climate change. But in the short term, California’s renewables are already grappling with rising temperatures.

Two records were smashed early this September that contributed to the loss of solar power. California surpassed 2 million acres burned in a single fire season for the first time (1.7 million more acres have burned since then). And on September 15th, small particle pollution reached the highest levels recorded since 2000, according to the California Air Resources Board. Winds that stoked the flames also drove pollution from the largest fires in Northern California to Southern California, where there are more solar farms.

Smaller residential and commercial solar systems were affected, too, and solar panels during grid blackouts typically shut off for safety, although smoke was the primary issue here. “A lot of my systems were producing zero power,” Steve Pariani, founder of the solar installation company Solar Pro Energy Systems, told the San Mateo Daily Journal in September.

As the planet heats up, California’s fire seasons have grown longer, and blazes are tearing through more land than ever before, while grid operators are also seeing rising curtailments as they integrate more renewables. For both utilities and smaller solar efforts, wildfire smoke will continue to darken solar energy’s otherwise bright future, even as it becomes the No. 3 renewable source in the U.S. by generation.

 

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UK breaks coal free energy record again but renewables still need more support

UK Coal-Free Grid Streak highlights record hours without coal, as renewable energy, wind and solar boost electricity generation, cutting CO2 emissions, reducing fossil fuel reliance, and accelerating grid decarbonization amid volatile gas markets.

 

Key Points

It is the UKs longest coal-free power run, driven by renewables, signaling decarbonization and reduced gas reliance.

✅ Record-breaking hours of electricity with zero coal generation

✅ Enabled by wind, solar, and growing offshore wind capacity

✅ Highlights need to cut gas use and expand renewable investment

 

Today is the fourth the UK has entered with not a watt of electricity generated by coal.

It’s the longest such streak since the 1880s and comes only days after the last modern era coal-free power record of 55 hours was set.

That represents good news for those of us who have children and would rather like there to be a planet for them to live on when we’re gone.

Coal generated power is dirty power, and not just through the carbon that gets pumped into the atmosphere when it burns.

The fact that the UK is increasingly able to call upon cleaner alternatives for its requirements, to the extent that records are being regularly broken and coal's share has fallen to record lows, is a welcome development.

The trouble is one of those alternatives is gas, and while it is better than coal it still throws off CO2, among other pollutants. The UK’s use of it, for electricity generation and most of its heating, comes with the added disadvantage of leaving it in hock to volatile international markets and producers that aren’t always friendly.

It was only last month, with the country in the middle of a cold snap, that the Grid was issuing a deficit warning (its first in eight years).

As I wrote at the time, we need to burn less of the stuff as low-carbon progress stalled in 2019 shows, too.

As such, Greenpeace’s call for more investment in renewable energy technology and generation, including solar, onshore wind and offshore wind, which is making an increasing contribution as wind beat coal in 2016 demonstrated, was well made.

Those who complain about onshore wind farms, particularly when they are built in windy places that are pretty, seem willfully blind to the pollution caused by gas.

The need to be listened to less. So do those, like British Gas owner Centrica, that bellyache about green taxes.

It bears repeating that fossil fuels are subsidised still more. It’s just that the subsidies are typically hidden.

A report issued last year by a coalition of environmental organisations found the UK provided $972m (£695m) of annual financing for fossil fuels on average between 2013 and 2015, compared with $172m for renewable energy.

But while they come up with wildly varying amounts as a result of wildly varying approaches, the OECD, the IMF and the International Energy Agency have all quantified substantial subsidies for fossils fuels. Their annual estimates have ranged from $160bn to $5.3tn (yes you read that rate and the number was the IMF’s) globally.

So by all means celebrate coal free days, and a full week without coal power as milestones. But we need more of them more quickly and we need more renewable energy to pick up the slack. As such, the philosophy and approach of government needs to change.

 

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Iran turning thermal power plants to combined cycle to save energy

Iran Combined-Cycle Power Plants drive energy efficiency, cut greenhouse gases, and expand megawatt capacity by converting thermal units; MAPNA-led upgrades boost grid reliability, reduce fuel use, and accelerate electricity generation growth nationwide.

 

Key Points

Upgraded thermal plants that reuse waste heat to boost efficiency, cut emissions, and add capacity to Iran's grid.

✅ 27 thermal plants converted; 160 more viable units identified

✅ Adds 12,600 MW capacity via heat recovery steam generators

✅ Combined-cycle share: 31.2% of 80.509 GW capacity

 

Iran has turned six percent of its thermal power plans into combined cycle plants in order to reduce greenhouse gases and save energy, with potential to lift thermal plants' PLF under rising demand, IRNA reported, quoting an energy official.

According to the MAPNA Group’s Managing Director Abbas Aliabadi, so far 27 thermal power plants have been converted to combined-cycle ones, aligning with Iran’s push to transmit power to Europe as a regional hub.

“The conversion of a thermal power plant to a combined cycle one takes about one to two years, however, it is possible for us to convert all the country’s thermal power plants into combined cycle plants over a five-year period.

Currently, a total of 478 thermal power plants are operating throughout Iran, of which 160 units could be turned into combined cycle plants. In doing so, 12,600 megawatts will be added to the country’s power capacity, supporting ongoing exports such as supplying a large share of Iraq's electricity under existing arrangements.

Related cross-border work includes deals to rehabilitate Iraq's power grid that support future exchanges.

As reported by IRNA on Wednesday, Iran’s Nominal electricity generation capacity has reached 80,509 megawatts (80.509 gigawatts), and it is deepening energy cooperation with Iraq to bolster regional reliability. The country increased its electricity generation capacity by 500 megawatts (MW) compared to the last year (ended on March 20).

Currently, with a total generation capacity of 25,083 MW (31.2 percent) combined cycle power plants account for the biggest share in the country’s total power generation capacity followed by gas power plants generating 29.9 percent, amid global trends where renewables are set to eclipse coal and regional moves such as Israel's coal reduction signal accelerating shifts. EF/MA

 

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Tackling climate change with machine learning: Covid-19 and the energy transition

Covid-19 Energy Transition and Machine Learning reshape climate change policy, electricity planning, and grid operations, from demand forecasting and decarbonization strategies in Europe to scalable electrification modeling and renewable integration across Africa.

 

Key Points

How the pandemic reshapes energy policy and how ML improves planning, demand forecasts, and grid reliability in Africa.

✅ Pandemic-driven demand shifts strain grid operations and markets

✅ Policy momentum risks rollback; favor future-oriented decarbonization

✅ ML boosts demand prediction, electrification, and grid reliability in Africa

 

The impact of Covid-19 on the energy system was discussed in an online climate change workshop that also considered how machine learning can help electricity planning in Africa.

This year’s International Conference on Learning Representations event included a workshop held by the Climate Change AI group of academics and artificial intelligence industry representatives, which considered how machine learning can help tackle climate change and highlighted advances by European electricity prediction specialists working in this field.

Bjarne Steffen, senior researcher at the energy politics group at ETH Zürich, shared his insights at the workshop on how Covid-19 and the accompanying economic crisis are affecting recently introduced ‘green’ policies. “The crisis hit at a time when energy policies were experiencing increasing momentum towards climate action, especially in Europe, and in proposals to invest in smarter electricity infrastructure for long-term resilience,” said Steffen, who added the coronavirus pandemic has cast into doubt the implementation of such progressive policies.

The academic said there was a risk of overreacting to the public health crisis, as far as progress towards climate change goals was concerned.

 

Lobbying

“Many interest groups from carbon-intensive industries are pushing to remove the emissions trading system and other green policies,” said Steffen. “In cases where those policies are having a serious impact on carbon-emitting industries, governments should offer temporary waivers during this temporary crisis, instead of overhauling the regulatory structure.”

However, the ETH Zürich researcher said any temptation to impose environmental conditions to bail-outs for carbon-intensive industries should be resisted. “While it is tempting to push a green agenda in the relief packages, tying short-term environmental conditions to bail-outs is impractical, given the uncertainty in how long this crisis will last,” he said. “It is better to include provisions that will give more control over future decisions to decarbonize industries, such as the government taking equity shares in companies.”

Steffen shared with pv magazine readers an article published in Joule which can be accessed here, and which articulates his arguments about how Covid-19 could affect the energy transition.

 

Covid-19 in the U.K.

The electricity system in the U.K. is also being affected by Covid-19, even as the U.S. electric grid grapples with climate risks, according to Jack Kelly, founder of London-based, not-for-profit, greenhouse gas emission reduction research laboratory Open Climate Fix.

“The crisis has reduced overall electricity use in the U.K.,” said Kelly. “Residential use has increased but this has not offset reductions in commercial and industrial loads.”

Steve Wallace, a power system manager at British electricity system operator National Grid ESO recently told U.K. broadcaster the BBC electricity demand has fallen 15-20% across the U.K. The National Grid ESO blog has stated the fall-off makes managing grid functions such as voltage regulation more challenging.

Open Climate Fix’s Kelly noted even events such as a nationally-coordinated round of applause for key workers was followed by a dramatic surge in demand, stating: “On April 16, the National Grid saw a nearly 1 GW spike in electricity demand over 10 minutes after everyone finished clapping for healthcare workers and went about the rest of their evenings.”

Climate Change AI workshop panelists also discussed the impact machine learning could have on improving electricity planning in Africa. The Electricity Growth and Use in Developing Economies (e-Guide) initiative funded by fossil fuel philanthropic organization the Rockefeller Foundation aims to use data to improve the planning and operation of electricity systems in developing countries.

E-Guide members Nathan Williams, an assistant professor at the Rochester Institute of Technology (RIT) in New York state, and Simone Fobi, a PhD student at Columbia University in NYC, spoke about their work at the Climate Change AI workshop, which closed on Thursday. Williams emphasized the importance of demand prediction, saying: “Uncertainty around current and future electricity consumption leads to inefficient planning. The weak link for energy planning tools is the poor quality of demand data.”

Fobi said: “We are trying to use machine learning to make use of lower-quality data and still be able to make strong predictions.”

The market maturity of individual solar home systems and PV mini-grids in Africa mean more complex electrification plan modeling is required, similar to integrating AI data centers into Canada's grids at scale.

 

Modeling

“When we are doing [electricity] access planning, we are trying to figure out where the demand will be and how much demand will exist so we can propose the right technology,” added Fobi. “This makes demand estimation crucial to efficient planning.”

Unlike many traditional modeling approaches, machine learning is scalable and transferable. Rochester’s Williams has been using data from nations such as Kenya, which are more advanced in their electrification efforts, to train machine learning models to make predictions to guide electrification efforts in countries which are not as far down the track.

Williams also discussed work being undertaken by e-Guide members at the Colorado School of Mines, which uses nighttime satellite imagery and machine learning to assess the reliability of grid infrastructure in India, where new algorithms to prevent ransomware-induced blackouts are also advancing.

 

Rural power

Another e-Guide project, led by Jay Taneja at the University of Massachusetts, Amherst – and co-funded by the Energy and Economic Growth program on development spending based at Berkeley – uses satellite imagery to identify productive uses of electricity in rural areas by detecting pollution signals from diesel irrigation pumps.

Though good quality data is often not readily available for Africa, Williams added, it does exist.

“We have spent years developing trusting relationships with utilities,” said the RIT academic. “Once our partners realize the value proposition we can offer, they are enthusiastic about sharing their data … We can’t do machine learning without high-quality data and this requires that organizations can effectively collect, organize, store and work with data. Data can transform the electricity sector, as shown by Canadian projects to use AI for energy savings, but capacity building is crucial.”

 

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Nonstop Records For U.S. Natural-Gas-Based Electricity

U.S. Natural Gas Power Demand is surging for electricity generation amid summer heat, with ERCOT, Texas grid reserves tight, EIA reporting coal and nuclear retirements, renewables intermittency, and pipeline expansions supporting combined-cycle capacity and prices.

 

Key Points

It is rising use of natural gas for power, driven by summer heat, plant retirements, and new combined-cycle capacity.

✅ ERCOT reserve margin 9%, below 14% target in Texas

✅ Gas share of U.S. power near 40-43% this summer

✅ Coal and nuclear retirements shift capacity to combined cycle

 

As the hot months linger, it will be natural gas that is leaned on most to supply the electricity that we need to run our air conditioning loads on the grid and keep us cool.

And this is surely a great and important thing: "Heat causes most weather-related deaths, National Weather Service says."

Generally, U.S. gas demand for power in summer is 35-40% higher than what it was five years ago, with so much more coming (see Figure).

The good news is regions across the country are expected to have plenty of reserves to keep up with power demand.

The only exception is ERCOT, covering 90% of the electric load in Texas, where a 9% reserve margin is expected, below the desired 14%.

Last summer, however, ERCOT’s reserve margin also was below the desired level, yet the grid operator maintained system reliability with no load curtailments.

Simply put, other states are very lucky that Texas has been able to maintain gas at 50% of its generation, despite being more than justified to drastically increase that.

At about 1,600 Bcf per year, the flatness of gas for power demand in Texas since 2000 has been truly remarkable, especially since Lone Star State production is up 50% since then.

Increasingly, other U.S. states (and even countries) are wanting to import huge amounts of gas from Texas, a state that yields over 25% of all U.S. output.

Yet if Texas justifiably ever wants to utilize more of its own gas, others would be significantly impacted.

At ~480 TWh per year, if Texas was a country, it would be 9th globally for power use, even ahead of Brazil, a fast growing economy with 212 million people, and France, a developed economy with 68 million people.

In the near-term, this explains why a sweltering prolonged heat wave in July in Texas, with a hot Houston summer setting new electricity records, is the critical factor that could push up still very low gas prices.

But for California, our second highest gas using state, above-average snowpack should provide a stronger hydropower for this summer season relative to 2018.

Combined, Texas and California consume about 25% of U.S. gas, with Texas' use double that of California.

 

Across the U.S., gas could supply a record 40-43% of U.S. electricity this summer even as the EIA expects solar and wind to be larger sources of generation across the mix

Our gas used for power has increased 35-40% over the past five years, and January power generation also jumped on the year, highlighting broad momentum.

Our gas used for power has increased 35-40% over the past five years. DATA SOURCE: EIA; JTC

Indeed, U.S. natural gas for electricity has continued to soar, even as overall electricity consumption has trended lower in some years, at nearly 10,700 Bcf last year, a 16% rise from 2017 and easily the highest ever.

Gas is expected to supply 37% of U.S. power this year, even as coal-fired generation saw a brief uptick in 2021 in EIA data, versus 27% just five years ago (see Figure).

Capacity wise, gas is sure to continue to surge its share 45% share of the U.S. power system.

"More than 60% of electric generating capacity installed in 2018 was fueled by natural gas."

We know that natural gas will continue to be the go-to power source: coal and nuclear plants are retiring, and while growing, wind and solar are too intermittent, geography limited, and transmission short to compensate like natural gas can.

"U.S. coal power capacity has fallen by a third since 2010," and last year "16 gigawatts (16,000 MW) of U.S. coal-fired power plants retired."

This year, some 2,000 MW of coal was retired in February alone, with 7,420 MW expected to be closed in 2019.

Ditto for nuclear.

Nuclear retirements this year include Pilgrim, Massachusetts’s only nuclear plant, and Three Mile Island in Pennsylvania.

This will take a combined ~1,600 MW of nuclear capacity offline.

Another 2,500 MW and 4,300 MW of nuclear are expected to be leaving the U.S. power system in 2020 and 2021, respectively.

As more nuclear plants close, EIA projects that net electricity generation from U.S. nuclear power reactors will fall by 17% by 2025.

From 2019-2025 alone, EIA expects U.S. coal capacity to plummet nearly 25% to 176,000 MW, with nuclear falling 15% to 83,000 MW.

In contrast, new combined cycle gas plants will grow capacity almost 30% to around 310,000 MW.

Lower and lower projected commodity prices for gas encourage this immense gas build-out, not to mention non-stop increases in efficiency for gas-based units.

Remember that these are official U.S. Department of Energy estimates, not coming from the industry itself.

In other words, our Department of Energy concludes that gas is the future.

Our hotter and hotter summers are therefore more and more becoming: "summers for natural gas"

Ultimately, this shows why the anti-pipeline movement is so dangerous.

"Affordable Energy Coalition Highlights Ripple Effect of Natural Gas Moratorium."

In April, President Trump signed two executive orders to promote energy infrastructure by directing federal agencies to remove bottlenecks for gas transport into the Northeast in particular, where New England oil-fired generation has spiked, and to streamline federal reviews of border-crossing pipelines and other infrastructure.

Builders, however, are not relying on outside help: all they know is that more U.S. gas demand is a constant, so more infrastructure is mandatory.

They are moving forward diligently: for example, there are now some 27 pipelines worth $33 billion already in the works in Appalachia.

 

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Egypt Plans Power Link to Saudis in $1.6 Billion Project

Egypt-Saudi Electricity Interconnection enables cross-border power trading, 3,000 MW capacity, and peak-demand balancing across the Middle East, boosting grid stability, reliability, and energy security through an advanced electricity network, interconnector infrastructure, and GCC grid integration.

 

Key Points

A 3,000 MW grid link letting Egypt and Saudi Arabia trade power, balance peak demand, and boost regional reliability.

✅ $1.6B project; Egypt invests ~$600M; 2-year construction timeline

✅ 3,000 MW capacity; peak-load shifting; cross-border reliability

✅ Links GCC grid; complements Jordan and Libya interconnectors

 

Egypt will connect its electricity network to Saudi Arabia, joining a system in the Middle East that has allowed neighbors to share power, similar to the Scotland-England subsea project that will bring renewable power south.

The link will cost about $1.6 billion, with Egypt paying about $600 million, Egypt’s Electricity Minister Mohamed Shaker said Monday at a conference in Cairo, as the country pursues a smart grid transformation to modernize its network. Contracts to build the network will be signed in March or April, and construction is expected to take about two years, he said. In times of surplus, Egypt can export electricity and then import power during shortages.

"It will enable us to benefit from the difference in peak consumption,” Shaker said. “The reliability of the network will also increase.”

Transmissions of electricity across borders in the Gulf became possible in 2009, when a power grid connected Qatar, Kuwait, Saudi Arabia and Bahrain, a dynamic also seen when Ukraine joined Europe's grid under emergency conditions. The aim of the grid is to ensure that member countries of the Gulf Cooperation Council can import power in an emergency. Egypt, which is not in the GCC, may have been able to avert an electricity shortage it suffered in 2014 if the link with Saudi Arabia existed at the time, Shaker said.

The link with Saudi Arabia should have a capacity of 3,000 megawatts, he said. Egypt has a 450-megawatt link with Jordan and one with Libya at 200 megawatts, the minister said. Egypt will seek to use its strategic location to connect power grids in Asia, where the Philippines power grid efforts are raising standards, and elsewhere in Africa, he said.

In 2009, a power grid linked Qatar, Kuwait, Saudi Arabia and Bahrain, allowing the GCC states to transmit electricity across borders, much like proposals for a western Canadian grid that aim to improve regional reliability. 

 

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