Doubts about Brazilian grid linger

Nighttime thermoradiative power converts outgoing infrared radiation into electricity using semiconductor photodiodes, leveraging negative illumination and sky cooling to harvest renewable energy from Earth-to-space heat flow when solar panels rest, regardless of weather.

Key Points

Nighttime thermoradiative power converts Earth's outgoing infrared heat into electricity using semiconductor diodes.

✅ Uses negative illumination to tap Earth-to-space heat flow

✅ Infrared semiconductor photodiodes generate small nighttime current

✅ Theoretical output ~4 W/m^2; lab demo reached 64 nW/m^2

There's a stark contrast between the freezing temperatures of space and the relatively balmy atmosphere of Earth, and that contrast could help generate electricity, scientists say – and alongside concepts such as space-based solar power, utilizing the same optoelectronic physics used in solar panels. The obvious difference this would have compared with solar energy is that it would work during the night time, a potential source of renewable power that could keep on going round the clock and regardless of weather conditions.

Solar panels are basically large-scale photodiodes - devices made out of a semiconducting material that converts the photons (light particles) coming from the Sun into electricity by exciting electrons in a material such as silicon, while concepts like space solar beaming could complement them during adverse weather.

In this experiment, the photodiodes work 'backwards': as photons in the form of infrared radiation - also known as heat radiation - leave the system, a small amount of energy is produced, similar to how raindrop electricity harvesting taps ambient fluxes in other experiments.

This way, the experimental system takes advantage of what researchers call the "negative illumination effect" – that is, the flow of outgoing radiation as heat escapes from Earth back into space. The setup explained in the new study uses an infrared semiconductor facing into the sky to convert this flow into electrical current.

"The vastness of the Universe is a thermodynamic resource," says one of the researchers, Shanhui Fan from Stanford University in California.

"In terms of optoelectronic physics, there is really this very beautiful symmetry between harvesting incoming radiation and harvesting outgoing radiation."

It's an interesting follow-up to a research project Fan participated in last year: a solar panel that can capture sunlight while also allowing excess heat in the form of infrared radiation to escape into space.

In the new study, this "energy harvesting from the sky" process can produce a measurable amount of electricity, the researchers have shown – though for the time being it's a long way from being efficient enough to contribute to our power grids, but advances in peer-to-peer energy sharing could still make niche deployments valuable.

In the team's experiments they were able to produce 64 nanowatts per square metre (10.8 square feet) of power – only a trickle, but an amazing proof of concept nevertheless. In theory, the right materials and conditions could produce a million times more than that, and analyses of cheap abundant electricity show how rapidly such advances compound, reaching about 4 watts per square metre.

"The amount of power that we can generate with this experiment, at the moment, is far below what the theoretical limit is," says one of the team, Masashi Ono from Stanford.

When you consider today's solar panels are able to generate up to 100-200 watts per square metre, and in China solar is cheaper than grid power across every city, this is obviously a long way behind. Even in its earliest form, though, it could be helpful for keeping low-power devices and machines running at night: not every renewable energy device needs to power up a city.

Now that the researchers have proved this can work, the challenge is to improve the performance of the experimental device. If it continues to show promise, the same idea could be applied to capture energy from waste heat given off by machinery, and results in humidity-powered generation suggest ambient sources are plentiful.

"Such a demonstration of direct power generation of a diode facing the sky has not been previously reported," explain the researchers in their published paper.

"Our results point to a pathway for energy harvesting during the night time directly using the coldness of outer space."

The research has been published in Applied Physics Letters.

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Virtual Power Plants orchestrate distributed energy resources like rooftop solar, home batteries, and EVs to deliver grid services, demand response, peak shaving, and resilience, lowering costs while enhancing reliability across wholesale markets and local networks.

Key Points

Virtual Power Plants aggregate solar and batteries to provide grid services, cut peak costs, and boost reliability.

✅ Aggregates DERs via cloud to bid into wholesale markets

✅ Reduces peak demand, defers costly grid upgrades

✅ Enhances resilience vs outages, cyber risks, and wildfires

If “virtual” meetings can allow companies to gather without anyone being in the office, then remotely distributed solar panels and batteries can harness energy and act as “virtual power plants.” It is simply the orchestration of millions of dispersed assets within a smarter electricity infrastructure to manage the supply of electricity — power that can be redirected back to the grid and distributed to homes and businesses. 

The ultimate goal is to revamp the energy landscape, making it cleaner and more reliable. By using onsite generation such as rooftop solar and smart solar inverters in combination with battery storage, those services can reduce the network’s overall cost by deferring expensive infrastructure upgrades and by reducing the need to purchase cost-prohibitive peak power. 

“We expect virtual power plants, including aggregated home solar and batteries, to become more common and more impactful for energy consumers throughout the country in the coming years,” says Michael Sachdev, chief product officer for Sunrun Inc., a rooftop solar company, in an interview. “The growth of home solar and batteries will be most apparent in places where households have an immediate need for backup power, as they do in California, where grid reliability pressures have led utilities to turn off the electricity to reduce wildfire risk.”

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Home battery adoption, such as Tesla Powerwall systems, is becoming commonplace in Hawaii and in New England, he adds, because those distributed assets are improving the efficiency of the electrical network. It is a trend that is reshaping the country’s energy generation and delivery system by relying more on clean onsite generation and less on fossil fuels.

Sunrun has recently formed a business partnership with AutoGrid, which will manage Sunrun’s fleet of rechargeable batteries. It is a cloud-based system that allows Sunrun to work with utilities to dispatch its “storage fleet” to optimize the economic results. AutoGrid compiles the data and makes AI-driven forecasts that enable it to pinpoint potential trouble spots. 

But a distributed energy system, or a virtual power plant, would have 200,000 subsystems. Or, 200,000 5 kilowatt batteries would be the equivalent of one power plant that has a capacity of 1,000 megawatts. 

“A virtual power plant acts as a generator,” says Amit Narayan, chief executive officer of AutoGrid, in an interview. “It is one of the top five innovations of the decade. If you look at Sunrun, 60% of every solar system it sells in the Bay Area is getting attached to a battery. The value proposition comes when you can aggregate these batteries and market them as a generation unit. The pool of individual assets may improve over time. But when you add these up, it is better than a large-scale plant. It is like going from mainframe computers to laptops.”

The AutoGrid executive goes on to say that centralized systems are less reliable than distributed resources. While one battery could falter, 200,000 of them that operate from remote locations will prove to be more durable — able to withstand cyber attacks and wildfires. Sunrun’s Sachdev adds that the ability to store energy in batteries, as seen in California’s expanding grid-scale battery use supporting reliability, and to move it to the grid on demand creates value not just for homes and businesses but also for the network as a whole.

The good news is that the trend worldwide is to make it easier for smaller distributed assets, including energy storage for microgrids that support local resilience, to get the same regulatory treatment as power plants. System operators have been obligated to call up those power supplies that are the most cost-effective and that can be easily dispatched. But now regulators are giving virtual power plants comprised of solar and batteries the same treatment. 

In the United States, for example, the Federal Energy Regulatory Commission issued an order in 2018 that allows storage resources to participate in wholesale markets — where electricity is bought directly from generators before selling that power to homes and businesses. Under the ruling, virtual power plants are paid the same as traditional power suppliers. A federal appeals court this month upheld the commission’s order, saying that it had the right to ensure “technological advances in energy storage are fully realized in the marketplace.” 

“In the past, we have used back-up generators,” notes AutoGrid’s Narayan. “As we move toward more automation, we are opening up the market to small assets such as battery storage and electric vehicles. As we deploy more of these assets, there will be increasing opportunities for virtual power plants.” 

Virtual power plants have the potential to change the energy horizon by harnessing locally-produced solar power and redistributing that to where it is most needed — all facilitated by cloud-based software that has a full panoramic view. At the same time, those smaller distributed assets can add more reliability and give consumers greater peace-of-mind — a dynamic that does, indeed, beef-up America’s generation and delivery network.

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P.E.I. Community Energy Independence empowers local microgrids through renewable generation, battery storage, and legislative reform, enabling community-owned power, stable electricity rates, and grid-friendly distributed generation across Island communities with wind, biomass, and net metering models.

Key Points

A program enabling communities to generate and store renewable power under supportive laws and grid-friendly models.

✅ Legislative review of Electric Power and Renewable Energy Acts

✅ Community microgrids with wind, biomass, and battery storage

✅ Grid integration without raising rates via Maritime Electric

The P.E.I. government is taking steps to review energy legislation and explore new options when it comes to generating power across Island communities.

Energy Minister Steven Myers said one of those options will be identifying ways for Island communities to generate their own energy, aligning with a federal electrification study now examining how electricity can reduce or eliminate fossil fuels. 

He said the move would provide energy independence, create jobs and economic development, and save the communities on their energy bills, as seen with an electricity bill credit in Newfoundland that eased costs for consumers.

But the move will require sweeping legislative changes, that may include the merging of the Electric Power Act and the Renewable Energy Act, similar to an electricity market overhaul in Connecticut seen in other jurisdictions.  

Myers said creating energy independence should ensure a steady supply of electricity while also ensuring costs remain reasonable for P.E.I. residents, even as a Nova Scotia electricity rate hike highlights regional cost pressures.   

"We have communities that are looking to generate their own electricity for their own needs," said Myers, adding the province will not dictate what energy sources communities can invest in. 

He also said the province wants to find new community-based models that will complement existing services.

"How do we do that in a way that we don't impact the grid, that we don't impact the service that Maritime Electric is delivering, mindful of a seasonal rate backlash in New Brunswick that illustrates consumer concerns, that we don't drive up the rates for all other Islanders."

Last fall, a group of P.E.I. MLAs traveled to Samsø, a small Danish island, where they learned about renewable and sustainable energy systems being used there.

The province is looking at storage options so it can store power generated during the day to be used in the evening when electricity use is at its highest. (CBC)
Samsø produces 100 per cent of its electricity from wind and biomass, and utilities like HECO meeting renewable goals early show how quickly transitions can occur. The P.E.I. government said the Island produces 25 per cent of its electricity from wind. 

Following the trip, Myers said he was impressed by the control the island had over its energy production and would like to see if a similar model could work on P.E.I. 

Myers said the legislative review will also look at different ways to store energy on the Island. 

He said that will allow communities to sell that excess energy into the provincial electricity grid, and those revenues could be redirected into that community's priorities. 

'For the survival and the future of their community'
"This is kind of a model that we had suggested that would be in place that would allow people in their own community to produce a revenue stream for themselves that they could then turn into projects like rinks, or parks, or tennis courts or whatever it is that community thinks is the most important thing for the survival and the future of their community," said Myers. 

Energy Minister Steven Myers says creating energy independence could create a steady supply of electricity while also ensuring costs remain reasonable for P.E.I. residents. (Randy McAndrew/CBC)
The province said Maritime Electric, Summerside Electric and the P.E.I. Energy Corporation will be involved in the review, recognizing that a Nova Scotia ruling on rate-setting powers underscores regulatory limits 

Government also wants to hear from Islanders and will be accepting written submissions beginning Monday. Myers said the province is also planning to host public consultations, but because of COVID-19, those will be held virtually in mid-June.

Myers calls this a major move, one that will take time. He said he doesn't expect the legislation to be made public until the spring of 2021.

"I want to make sure we take our time and do the proper consultation."

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Renewable Energy Security strengthens affordability and grid reliability through electrification, wind, and solar, reducing fossil fuel volatility exposed by the Ukraine crisis, aligning with IEA guidance and the Paris Agreement to deliver resilient, low-cost power.

Key Points

Renewable energy security is reliable, affordable power from electrification, wind and solar, cutting fossil fuel risk.

✅ Wind and solar now outcompete gas for new power capacity.

✅ Diversifies supply and reduces fossil price volatility.

✅ Requires grid flexibility, storage, and demand response.

Oil, gas, and coal have been the central pillar of the global energy system throughout the 20th century. And for decades, these fossil fuels have been closely associated with energy security.  

The perception of energy security, however, is rapidly changing. Renewables form an increasing share of energy sectors worldwide as countries look to deliver on the Paris Agreement and mitigate the effects of climate change, with IEA clean energy investment now significantly outpacing fossil fuels. Moreover, Russia’s invasion of Ukraine has demonstrated how relying on fossil fuels for power, heating, and transport has left many countries vulnerable or energy insecure.  

The International Energy Agency (IEA) defines energy security as “the uninterrupted availability of energy sources at an affordable price” (IEA, 2019a). This definition hardly describes today’s global energy situation, with the cancellation of natural gas deliveries and skyrocketing prices for oil and gas products, and with supply chain challenges in clean energy that also require attention. These circumstances have cascading effects on electricity prices in countries like the United Kingdom that rely heavily on natural gas to produce electricity. In Europe, energy insecurity has been even further amplified since the Russian corporation Gazprom recently cut off gas supplies to several countries.  

As a result, energy security has gained new urgency in Canada and worldwide, creating opportunities in the global electricity market for Canada. Recent events provide a stark reminder of the volatility and potential vulnerability of global fossil fuel markets and supply chains. Even in Canada, as one of the largest producers of oil and gas in the world, the price of fuels depends on global and regional market forces rather than government policy or market design. Thus, the average monthly price for gasoline in Canada hit a record high of CAD 2.07 per litre in May 2022 (Figure 1), and natural gas prices surged to a record CAD 7.54 per MMBtu in May 2022 (Figure 2).  

Energy price increases of this magnitude are more than enough to strain Canadian household budgets. But on top of that, oil and gas prices have accelerated inflation more broadly as it has become more expensive to produce, transport, and store goods, including food and other basic commodities (Global News, 2022).  

Renewable Energy Is More Affordable 

In contrast to oil and gas, renewable energy can reliably deliver affordable energy, as shown by falling wholesale electricity prices in markets with growing clean power. This is a unique and positive aspect of today’s energy crisis compared to historical crises: options for electrification and renewable-based electricity systems are both available and cost-effective.  

For new power capacity, wind and solar are now cheaper than any other source, and wind power is making gains as a competitive source in Canada. According to Equinor (2022), wind and solar were already cheaper than gas-based power in 2020. This means that renewable energy was already the cheaper option for new power before the recent natural gas price spikes. As illustrated in Figure 3, the cost of new renewable energy has dropped so dramatically that, for many countries, it is cheaper to install new solar or wind infrastructure than to keep operating existing fossil fuel-based power plants (International Renewable Energy Agency, 2021). This means that replacing fossil-based electricity generation with renewables would save money and reduce emissions. Wind and solar prices are expected to continue their downward trends as more countries increase deployment and learn how to best integrate these sources into the grid. 

Renewable Energy Is Reliable 

To deliver on the uninterrupted availability side of the energy security equation, renewable power must remain reliable even as more variable energy sources, like wind and solar, are added to the system, and regional leaders such as the Prairie provinces will help anchor this transition. For Canada and other countries to achieve high energy security through electrification, grid system operations must be able to support this, and pathways to zero-emissions electricity by 2035 are feasible.  

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Pickering Nuclear Alert Error prompts Ontario investigation into the Alert Ready emergency alert system, Pelmorex safeguards, and public response at Pickering Nuclear Generating Station, including potassium iodide orders and geo-targeted notification issues.

Key Points

A mistaken Ontario emergency alert about the Pickering plant, now under probe for human error and system safeguards.

✅ Investigation led by Emergency Management Ontario

✅ Alert Ready and Pelmorex safeguards under review

✅ KI pill demand surged; geo-targeting questioned

A number of questions still remain a week after an emergency alert was mistakenly sent out to people across Ontario warning of an unspecified incident at the Pickering Nuclear Generating Station. 

The province’s solicitor general has stepped in and says an investigation into the incident should be completed fairly quickly according to the minister.

However, the nuclear scare has still left residents on edge with tens of thousands of people ordering potassium iodide, or KI, pills that protect the body from radioactive elements in the days following the incident.

Here’s what we know and still don’t know about the mistaken Pickering nuclear plant alert:

Who sent the alert?

According to the Alert Ready Emergency Alert System website, the agency works with several federal, provincial and territorial emergency management officials, Environment and Climate Change Canada and Pelmorex, a broadcasting industry and wireless service provider, to send the alerts.

Martin Belanger, the director of public alerting for Pelmorex, a company that operates the alert system, said there are a number of safeguards built in, including having two separate platforms for training and live alerts.

"The software has some steps and some features built in to minimize that risk and to make sure that users will be able to know whether or not they're sending an alert through the... training platform or whether they're accessing the live system in the case of a real emergency," he said.

Only authorized users have access to the system and the province manages that, Belanger said. Once in the live system, features make the user aware of which platform they are using, with various prompts and messages requiring the user's confirmation. There is a final step that also requires the user to confirm their intent of issuing an alert to cellphones, radio and TVs, Belanger said.

Last Sunday, a follow-up alert was sent to cellphones nearly two hours after the original notification, and during separate service disruptions such as a power outage in London residents also sought timely information.

What has the investigation revealed?

It’s still unclear as to how exactly the alert was sent in error, but Solicitor General Sylvia Jones has tapped the Chief of Emergency Management Ontario to investigate.

"It's very important for me, for the people of Ontario, to know exactly what happened on Sunday morning," Jones said.

Jones said initial observations suggest human error was responsible for the alert that was sent out during routine tests of the emergency alert.

“I want to know what happened and equally important, I want some recommendations on insurances and changes we can make to the system to make sure it doesn't happen again,” Jones said.

Jones said she expects the results of the probe to be made public.

Can you unsubscribe from emergency alerts?

It’s not possible to opt out of receiving the alerts, according to the Alert Ready Emergency Alert System website, and Ontario utilities warn about scams to help customers distinguish official notices.

“Given the importance of warning Canadians of imminent threats to the safety of life and property, the CRTC requires wireless service providers to distribute alerts on all compatible wireless devices connected to an LTE network in the target area,” the website reads.

The agency explains that unlike radio and TV broadcasting, the wireless public alerting system is geo-targeted and is specific to the a “limited area of coverage”, and examples like an Alberta grid alert have highlighted how jurisdictions tailor notices for their systems.

“As a result, if an emergency alert reaches your wireless device, you are located in an area where there is an imminent danger.”

The Pickering alert, however, was received by people from as far as Ottawa to Windsor.

Is the Pickering Nuclear Generating Station closing?

The Pickering nuclear plant has been operating since 1971, and had been scheduled to be decommissioned this year, but the former Liberal government -- and the current Progressive Conservative government -- committed to keeping it open until 2024. Decommissioning is now set to start in 2028.

It operates six CANDU reactors, and in contingency planning operators have considered locking down key staff to maintain reliability, generates 14 per cent of Ontario's electricity and is responsible for 4,500 jobs across the region, according to OPG, while utilities such as Hydro One's relief programs have supported customers during broader crises.

What should I do if I receive an emergency alert?

Alert Ready says that if you received an alert on your wireless device it’s important to take action “safely”.

“Stop what you are doing when it is safe to do so and read the emergency alert,” the agency says on their website.

“Alerting authorities will include within the emergency alert the information you need and guidance for any action you are required to take, and insights from U.S. grid pandemic response underscore how critical infrastructure plans intersect with public safety.”

“This could include but is not limited to: limit unnecessary travel, evacuate the areas, seek shelter, etc.”

The wording of last Sunday's alert caused much initial confusion, warning residents within 10 kilometres of the plant of "an incident," though there was no "abnormal" release of radioactivity and residents didn't need to take protective steps, but emergency crews were responding.

“In the event of a real emergency, the wording would be different,” Jones said.

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Bitcoin Energy Consumption drives debate on blockchain mining, proof-of-work, carbon footprint, and emissions, with CCAF estimates in terawatt hours highlighting electricity demand, fossil fuel reliance, and sustainability concerns for data centers and cryptocurrency networks.

Key Points

Electricity used by Bitcoin proof-of-work mining, often fossil-fueled, estimated by CCAF in terawatt hours.

✅ CCAF: 40-445 TWh, central estimate ~130 TWh

✅ ~66% of mining electricity sourced from fossil fuels

✅ Proof-of-work increases hash rate, energy, and emissions

The University of Cambridge Centre for Alternative Finance (CCAF) studies the burgeoning business of cryptocurrencies.

It calculates that Bitcoin's total energy consumption is somewhere between 40 and 445 annualised terawatt hours (TWh), with a central estimate of about 130 terawatt hours.

The UK's electricity consumption is a little over 300 TWh a year, while Argentina uses around the same amount of power as the CCAF's best guess for Bitcoin, as countries like New Zealand's electricity future are debated to balance demand.

And the electricity the Bitcoin miners use overwhelmingly comes from polluting sources, with the U.S. grid not 100% renewable underscoring broader energy mix challenges worldwide.

The CCAF team surveys the people who manage the Bitcoin network around the world on their energy use and found that about two-thirds of it is from fossil fuels, and some regions are weighing curbs like Russia's proposed mining ban amid electricity deficits.

Huge computing power - and therefore energy use - is built into the way the blockchain technology that underpins the cryptocurrency has been designed.

It relies on a vast decentralised network of computers.

These are the so-called Bitcoin "miners" who enable new Bitcoins to be created, but also independently verify and record every transaction made in the currency.

In fact, the Bitcoins are the reward miners get for maintaining this record accurately.

It works like a lottery that runs every 10 minutes, explains Gina Pieters, an economics professor at the University of Chicago and a research fellow with the CCAF team.

Data processing centres around the world, including hotspots such as Iceland's mining strain, race to compile and submit this record of transactions in a way that is acceptable to the system.

They also have to guess a random number.

The first to submit the record and the correct number wins the prize - this becomes the next block in the blockchain.

Estimates for bitcoin's electricity consumption
At the moment, they are rewarded with six-and-a-quarter Bitcoins, valued at about $50,000 each.

As soon as one lottery is over, a new number is generated, and the whole process starts again.

The higher the price, says Prof Pieters, the more miners want to get into the game, and utilities like BC Hydro suspending new crypto connections highlight grid pressures.

"They want to get that revenue," she tells me, "and that's what's going to encourage them to introduce more and more powerful machines in order to guess this random number, and therefore you will see an increase in energy consumption," she says.

And there is another factor that drives Bitcoin's increasing energy consumption.

The software ensures it always takes 10 minutes for the puzzle to be solved, so if the number of miners is increasing, the puzzle gets harder and the more computing power needs to be thrown at it.

Bitcoin is therefore actually designed to encourage increased computing effort.

The idea is that the more computers that compete to maintain the blockchain, the safer it becomes, because anyone who might want to try and undermine the currency must control and operate at least as much computing power as the rest of the miners put together.

What this means is that, as Bitcoin gets more valuable, the computing effort expended on creating and maintaining it - and therefore the energy consumed - inevitably increases.

We can track how much effort miners are making to create the currency.

They are currently reckoned to be making 160 quintillion calculations every second - that's 160,000,000,000,000,000,000, in case you were wondering.

And this vast computational effort is the cryptocurrency's Achilles heel, says Alex de Vries, the founder of the Digiconomist website and an expert on Bitcoin.

All the millions of trillions of calculations it takes to keep the system running aren't really doing any useful work.

"They're computations that serve no other purpose," says de Vries, "they're just immediately discarded again. Right now we're using a whole lot of energy to produce those calculations, but also the majority of that is sourced from fossil energy, and clean energy's 'dirty secret' complicates substitution."

The vast effort it requires also makes Bitcoin inherently difficult to scale, he argues.

"If Bitcoin were to be adopted as a global reserve currency," he speculates, "the Bitcoin price will probably be in the millions, and those miners will have more money than the entire [US] Federal budget to spend on electricity."

"We'd have to double our global energy production," he says with a laugh, even as some argue cheap abundant electricity is getting closer to reality today. "For Bitcoin."

He says it also limits the number of transactions the system can process to about five per second.

This doesn't make for a useful currency, he argues.

Rising price of bitcoin graphic
And that view is echoed by many eminent figures in finance and economics.

The two essential features of a successful currency are that it is an effective form of exchange and a stable store of value, says Ken Rogoff, a professor of economics at Harvard University in Cambridge, Massachusetts, and a former chief economist at the International Monetary Fund (IMF).

He says Bitcoin is neither.

"The fact is, it's not really used much in the legal economy now. Yes, one rich person sells it to another, but that's not a final use. And without that it really doesn't have a long-term future."

What he is saying is that Bitcoin exists almost exclusively as a vehicle for speculation.

So, I want to know: is the bubble about to burst?

"That's my guess," says Prof Rogoff and pauses.

"But I really couldn't tell you when."

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