Distributed Energy Systems and Canada's Energy Future

PG&E Wind Shutdown and Renewable Reliability examines PSPS strategy, wildfire risk, transmission line exposure, wind turbine cut-out speeds, grid stability, and California's energy mix amid historic high-wind events and supply constraints across service areas.

Key Points

An overview of PG&E's PSPS decisions, wildfire mitigation, and how wind cut-out limits influence grid reliability.

✅ Wind turbines reach cut-out near 55 mph, reducing generation.

✅ PSPS mitigates ignition from damaged transmission infrastructure.

✅ Baseload diversity improves resilience during high-wind events.

According to the official, widely reported story, Pacific Gas & Electric (PG&E) initiated power shutoffs across substantial portions of its electric transmission system in northern California as a precautionary measure.

Citing high wind speeds they described as “historic,” the utility claims that if it didn’t turn off the grid, wind-caused damage to its infrastructure could start more wildfires.

Perhaps that’s true. Perhaps. This tale presumes that the folks who designed and maintain PG&E’s transmission system are unaware of or ignored the need to design it to withstand severe weather events, and that the Federal Energy Regulatory Commission (FERC) and North American Electric Reliability Corp. (NERC) allowed the utility to do so.

Ignorance and incompetence happens, to be sure, but there’s much about this story that doesn’t smell right—and it’s disappointing that most journalists and elected officials are apparently accepting it without question.

Take, for example, this statement from a Fox News story about the Kincade Fires: “A PG&E meteorologist said it’s ‘likely that many trees will fall, branches will break,’ which could damage utility infrastructure and start a fire.”

Did you ever notice how utilities cut wide swaths of trees away when transmission lines pass through forests? There’s a reason for that: When trees fall and branches break, the grid can still function, and even as the electric rhythms of New York City shifted during COVID-19, operators planned for variability.

So, if badly designed and poorly maintained infrastructure isn’t the reason PG&E cut power to millions of Californians, what might have prompted them to do so? Could it be that PG&E’s heavy reliance on renewable energy means they don’t have the power to send when a “historic” weather event occurs, especially as policymakers weigh the postponed closure of three power plants elsewhere in California?

Wind Speed Limits

The two most popular forms of renewable energy come with operating limitations, which is why some energy leaders urge us to keep electricity options open when planning the grid. With solar power, the constraint is obvious: the availability of sunlight. One doesn’t generate solar power at night and energy generation drops off with increasing degrees of cloud cover during the day.

The main operating constraint of wind power is, of course, wind speed, and even in markets undergoing 'transformative change' in wind generation, operators adhere to these technical limits. At the low end of the scale, you need about a 6 or 7 miles-per-hour wind to get a turbine moving. This is called the “cut-in speed.” To generate maximum power, about a 30 mph wind is typically required. But, if the wind speed is too high, the wind turbine will shut down. This is called the “cut-out speed,” and it’s about 55 miles per hour for most modern wind turbines.

It may seem odd that wind turbines have a cut-out speed, but there’s a very good reason for it. Each wind turbine rotor is connected to an electric generator housed in the turbine nacelle. The connection is made through a gearbox that is sized to turn the generator at the precise speed required to produce 60 Hertz AC power.

The blades of the wind turbine are airfoils, just like the wings of an airplane. Adjusting the pitch (angle) of the blades allows the rotor to maintain constant speed, which, in turn, allows the generator to maintain the constant speed it needs to safely deliver power to the grid. However, there’s a limit to blade pitch adjustment. When the wind is blowing so hard that pitch adjustment is no longer possible, the turbine shuts down. That’s the cut-out speed.

Now consider how California’s power generation profile has changed. According to Energy Information Administration data, the state generated 74.3 percent of its electricity from traditional sources—fossil fuels and nuclear, amid debates over whether to classify nuclear as renewable—in 2001. Hydroelectric, geothermal, and biomass-generated power accounted for most of the remaining 25.7 percent, with wind and solar providing only 1.98 percent of the total.

By 2018, the state’s renewable portfolio had jumped to 43.8 percent of total generation, with clean power increasing and wind and solar now accounting for 17.9 percent of total generation. That’s a lot of power to depend on from inherently unreliable sources. Thus, it wouldn’t be at all surprising to learn that PG&E didn’t stop delivering power out of fear of starting fires, but because it knew it wouldn’t have power to deliver once high winds shut down all those wind turbines

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Georgia Power June bill credit delivers PSC-approved savings, lower fuel rates, and COVID-19 relief for residential customers, driven by natural gas prices and 2018 earnings, with typical 1,000 kWh users seeing June bill reductions.

Key Points

A PSC-approved one-time credit and lower fuel rates reducing June bills for Georgia Power residential customers.

✅ $11.29 credit for 1,000 kWh usage on June bills

✅ Fuel rate cut saves $10.26 per month from June to September 2020

✅ PSC-approved $51.5M credit based on Georgia Power's 2018 results

Georgia Power announced that the typical residential customer using 1,000-kilowatt hours will receive an $11.29 credit on their June bill, reflecting a lump-sum credit model also used elsewhere.

This reflects implementation of a one-time $51.5 million credit for customers, similar to Gulf Power's bill decrease efforts, approved by the Georgia Public Service Commission, as a result of

Georgia Power's 2018 financial results.

Pairing the June credit with new, lower fuel rates recently announced, the typical residential customer would see a reduction of $21.55 in June, even as some regions face increases like Pennsylvania's winter price hikes elsewhere.

The amount each customer receives will vary based on their 2018 usage. Georgia Power will apply the credit to June bills for customers who had active accounts as of Dec. 31, 2018, and are still active or receiving a final bill as of June 2020, and the company has issued pandemic scam warnings to help customers stay informed.

Fuel rate lowered 17.2 percent

In addition to the approved one-time credit in June, the Georgia PSC recently approved Georgia Power’s plan to reduce its fuel rates by 17.2 percent and total billings by approximately $740 million over a two-year period. The implementation of a special interim reduction will provide customers additional relief during the COVID-19 pandemic through even lower fuel rates over the upcoming 2020 summer months. The lower fuel rate and special interim reduction will lower the total bill of a typical residential customer using an average of 1,000-kilowatt hours by a total of $10.26 per month from June through September 2020.

The reduction in the company’s fuel rate is driven primarily by lower natural gas prices, even as FPL proposed multiyear rate hikes in Florida, as a result of increased natural gas supplies, which the company is able to take advantage of to benefit customers due to its diverse generation sources.

February bill credit due to tax law savings

Georgia Power completed earlier this year the third and final bill credit associated with the Tax Cuts and Jobs Act of 2017, resulting in credits totaling $106 million. The typical residential customer using an average of 1,000 kilowatt-hours per month received a credit of approximately $22 on their February Georgia Power bill, a helpful offset as U.S. electric bills rose 5% in 2022 according to national data.

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Site C 500 kV transmission lines strengthen the BC Hydro grid, linking the new substation and Peace Canyon via a 75 kilometre right-of-way to deliver clean energy, with 400 towers built and both circuits energized.

Key Points

High-voltage lines connecting Site C substation to the BC Hydro grid, delivering clean energy via Peace Canyon.

✅ Two 75 km circuits between Site C and Peace Canyon

✅ Connect new 500 kV substation to BC Hydro grid

✅ Over 400 towers built along existing right-of-way

The second and final 500 kilovolt, 75 kilometre transmission line on the Site C project, which has faced stability questions in recent years, has been completed and energized.

With this milestone, the work to connect the new Site C substation to the BC Hydro grid, amid treaty rights litigation that has at times shaped schedules, is complete. Once the Site C project begins generating electricity, much like when the Maritime Link first power flowed between Newfoundland and Nova Scotia, the transmission lines will help deliver clean energy to the rest of the province.

The two 75 kilometre transmission lines run along an existing right-of-way between Site C and the Peace Canyon generating station, a route that has seen community concerns from some northerners. The project’s first 500 kilovolt, 75 kilometre transmission line – along with the Site C substation – were both completed and energized in the fall of 2020.

BC Hydro awarded the Site C transmission line construction contract to Allteck Line Contractors Inc. (now Allteck Limited Partnership) in 2018. Since construction started on this part of the project in summer 2018, crews have built more than 400 towers and strung lines, even as other interties like the Manitoba-Minnesota line have faced scheduling uncertainty, over a total of 150 kilometres.

The two transmission lines are a major component of the Site C project, comparable to initiatives such as the New England Clean Power Link in scale, which also consists of the new 500 kilovolt substation and expanding the existing Peace Canyon 500 kilovolt gas-insulated switchgear to incorporate the two new 500 kilovolt transmission line terminals.

Work to complete three other 500 kilovolt transmission lines that will span one kilometre between the Site C generating station and Site C substation, similar to milestones on the Maritime Link project, is still underway. This work is expected to be complete in 2023.

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Manitoba Hydro Phone Scam targets small businesses with disconnection threats, prepaid card payments, caller ID spoofing, phishing texts, and door-to-door fraud; hang up, verify your account directly, and never share banking information.

Key Points

A scam where callers threaten disconnection and demand prepaid cards; verify account status directly with Manitoba Hydro.

✅ Hang up and call Manitoba Hydro at 1-888-624-9376 to verify.

✅ Never pay by prepaid cards, gift cards, or crypto.

✅ Hydro will not cut power on one-hour notice.

Manitoba Hydro is warning customers, particularly small business owners, to be wary of high-pressure scammers, as Ontario utilities warn of scams in other provinces, threatening to shut off their electricity.

The callers demand the customer to make immediate payment by a prepaid card. Often, the calls are made in the middle of the day at a busy time, frightening the customer with aggressive threats about disconnection, as hydro disconnections have made headlines elsewhere, says hydro spokesman Bruce Owen.

"They tell them 'we have a truck on the way to cut off your power. If you don't pay in the next hour you're out of luck,'" he said.

"And because these folks have inventory in freezers and they have customers … they're willing to fork over several hundred or even several thousand dollars on a prepaid card to somebody they don't know to keep the lights on."

Maybe the business owners can't recall, with everything happening, including discussions about Hydro One peak rates in Ontario, if they've made their payments on time. They start second-guessing and believing the person on the other line, Owen says.

And they worry about losing thousands of dollars in business if they lose power. So they're more than willing to run out to a store, buy a prepaid debit card and provide the number to the caller.

"Their goal is to manipulate you into sending money before you figure out it's a scam," said Chris McColm, hydro's security and investigations supervisor. "These people are crooks and you should hang up on them."

For any customers that are in arrears, hydro will work with them to resolve the issue, Owen said.

"We do not have to take that extreme measure of cutting off or disconnecting anybody. That's not the business we're in — we don't strong arm people that way," he said.

"Anybody who's threatening to cut off your power with an hour or half-an-hour notice, well it's it's no better than someone waiting around the corner, waiting the club you over the head in the dark of night. That's what they are."

Fraud reports soar

The power utility has recorded a nearly-300 per cent jump in the number of fraud-related complaints this year over 2017. There have been 862 phone, text and e-mail scams and that could still go much higher.

The current statistics from 2018 have only calculated up to Oct. 31. In 2017, there were 221.

That jump in numbers doesn't necessarily mean there are more scammers out there.

It could simply mean people are finally getting wise to fraudsters and reporting it more, Owen says.

"At the same token, we don't hear of everybody who's been taking advantage of because once they've found out that they've been hoodwinked they don't want to tell anybody because they're so embarrassed," he said.

"These scammers can be very convincing and anyone can be victimized," McColm said.

If you are able to think clearly when some high-pressure caller gets you on the line, Owen suggests asking a few simple questions to challenge their legitimacy:

• What street am I on?
• What does my business look like? 
• What's the weather outside right now?

Phone scammers can falsify their caller ID information to make it appear they're calling from a local number, but what you'll find is most of them aren't in Winnipeg or Manitoba and likely not even this country or continent, Owen says.

The key to being safe is simply to never give out banking information, Owen says. It's a message that has been stressed for years and 80-90 per cent of people understand it, but it's that other 10-20 per cent that are still being victimized.And it's not just phone calls. Many other fraud-related complaints to Manitoba Hydro this year concerned unsolicited text messages to customers saying they had been overbilled, or faced retroactive charges elsewhere, and were eligible for a refund.

This scam is also aimed at getting a customer's personal banking information, under the guise of having money put back into their account.

Also, many people, especially seniors living alone, continue to be targeted by aggressive door-to-door fraudsters, and cases like the electricity theft ring in Montreal underscore the risks, McColm says. However, he adds, hydro employees always display photo ID and will never demand to come into a home. 

If you're unsure whether a phone call, text or email is real or a scam, contact Manitoba Hydro at 1-888-624-9376.

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Illinois Zero Emission Credits support nuclear plants via tradable credits tied to wholesale electricity prices, carbon costs, created by the Future Energy Jobs Bill to avert Exelon closures and sustain low-carbon power.

Key Points

State credits that value nuclear power's zero-carbon output, priced by market and carbon metrics to keep plants running.

✅ Pegged to wholesale prices, carbon costs, and state averages.

✅ Created by Future Energy Jobs Bill to prevent plant retirements.

✅ Supports Exelon Quad Cities and Clinton nuclear facilities.

Nuclear plants have produced over half of Illinois electricity generation since 2010, but the states two largest plants would have been retired amid the debate over saving nuclear plants if the state had not created a zero emission credit (ZEC) mechanism to support the facilities.

The two plants, Quad Cities and Clinton, collectively delivered more than 12 percent of the states electricity generation over the past several years. In May 2016, however, Exelon, the owner of the plants, announced that they had together lost over $800 million dollars over the previous six years and revealed plans to retire them in 2017 and 2018, similar to the Three Mile Island closure later announced for 2019 by its owner.

In December 2016, Illinois passed the Future Energy Jobs Bill, which established a zero emission credit (ZEC) mechanism

to support the plants financially. Exelon then cancelled its plans to retire the two facilities.

The ZEC is a tradable credit that represents the environmental attributes of one megawatt-hour of energy produced from the states nuclear plants. Its price is based on a number of factors that include wholesale electricity market prices, nuclear generation costs, state average market prices, and estimated costs of the long-term effects of carbon dioxide emissions.

The bill is set to take effect in June, but faces multiple court challenges as some utilities have expressed concerns that the ZEC violates the commerce clause and affects federal authority to regulate wholesale energy prices, amid gas-fired competition in nearby markets that shapes the revenue outlook.

Illinois ranks first in the United States for both generating capacity and net electricity generation from nuclear power, a resource many see as essential for net-zero emissions goals, and accounts for approximately one-eighth of the nuclear power generation in the nation.

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Near-Field Thermophotovoltaics captures radiated energy across a nanoscale gap, using thin-film photovoltaic cells and indium gallium arsenide to boost power density and efficiency, enabling compact Army portable power from emitters via radiative heat transfer.

Key Points

A nanoscale TPV method capturing near-field photons for higher power density at lower emitter temperatures.

✅ Nanoscale gap boosts radiative transfer and usable photon flux

✅ Thin-film InGaAs cells recycle sub-band-gap photons via reflector

✅ Achieved ~5 kW/m2 power density with higher efficiency

With the addition of sensors and enhanced communication tools, providing lightweight, portable power has become even more challenging, with concepts such as power from falling snow illustrating how diverse new energy-harvesting approaches are. Army-funded research demonstrated a new approach to turning thermal energy into electricity that could provide compact and efficient power for Soldiers on future battlefields.

Hot objects radiate light in the form of photons into their surroundings. The emitted photons can be captured by a photovoltaic cell and converted to useful electric energy. This approach to energy conversion is called far-field thermophotovoltaics, or FF-TPVs, and has been under development for many years; however, it suffers from low power density and therefore requires high operating temperatures of the emitter.

The research, conducted at the University of Michigan and published in Nature Communications, demonstrates a new approach, where the separation between the emitter and the photovoltaic cell is reduced to the nanoscale, enabling much greater power output than what is possible with FF-TPVs for the same emitter temperature.

This approach, which enables capture of energy that is otherwise trapped in the near-field of the emitter is called near-field thermophotovoltaics or NF-TPV and uses custom-built photovoltaic cells and emitter designs ideal for near-field operating conditions, alongside emerging smart solar inverters that help manage conversion and delivery.

This technique exhibited a power density almost an order of magnitude higher than that for the best-reported near-field-TPV systems, while also operating at six-times higher efficiency, paving the way for future near-field-TPV applications, including remote microgrid deployments in extreme environments, according to Dr. Edgar Meyhofer, professor of mechanical engineering, University of Michigan.

"The Army uses large amounts of power during deployments and battlefield operations and must be carried by the Soldier or a weight constrained system," said Dr. Mike Waits, U.S. Army Combat Capabilities Development Command's Army Research Laboratory. "If successful, in the future near-field-TPVs could serve as more compact and higher efficiency power sources for Soldiers as these devices can function at lower operating temperatures than conventional TPVs."

The efficiency of a TPV device is characterized by how much of the total energy transfer between the emitter and the photovoltaic cell is used to excite the electron-hole pairs in the photovoltaic cell, where insights from near-light-speed conduction research help contextualize performance limits in semiconductors. While increasing the temperature of the emitter increases the number of photons above the band-gap of the cell, the number of sub band-gap photons that can heat up the photovoltaic cell need to be minimized.

"This was achieved by fabricating thin-film TPV cells with ultra-flat surfaces, and with a metal back reflector," said Dr. Stephen Forrest, professor of electrical and computer engineering, University of Michigan. "The photons above the band-gap of the cell are efficiently absorbed in the micron-thick semiconductor, while those below the band-gap are reflected back to the silicon emitter and recycled."

The team grew thin-film indium gallium arsenide photovoltaic cells on thick semiconductor substrates, and then peeled off the very thin semiconductor active region of the cell and transferred it to a silicon substrate, informing potential interfaces with home battery systems for distributed use.

All these innovations in device design and experimental approach resulted in a novel near-field TPV system that could complement distributed resources in virtual power plants for resilient operations.

"The team has achieved a record ~5 kW/m2 power output, which is an order of magnitude larger than systems previously reported in the literature," said Dr. Pramod Reddy, professor of mechanical engineering, University of Michigan.

Researchers also performed state-of-the-art theoretical calculations to estimate the performance of the photovoltaic cell at each temperature and gap size, informing hybrid designs with backup fuel cell solutions that extend battery life, and showed good agreement between the experiments and computational predictions.

"This current demonstration meets theoretical predictions of radiative heat transfer at the nanoscale, and directly shows the potential for developing future near-field TPV devices for Army applications in power and energy, communication and sensors," said Dr. Pani Varanasi, program manager, DEVCOM ARL that funded this work.

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