DC power gaining wider acceptance

By Reuters


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During the late 1800s Thomas Edison and George Westinghouse were engaged in an intense industrial rivalry.

Edison's electrical inventions ran on DC direct current. Westinghouse tried to convince governments and business that AC alternating current was the way to go for the development of large-scale power distribution systems. In their book American Entrepreneur: The Fascinating Stories of the People Who Defined Business in the United States, Larry Schweikart and Lynne Pierson Doti retell how the battle got pretty nasty.

"Edison's company enthusiastically publicized accidents from AC voltage, to the point of conducting experiments in which cats were electrocuted to show its dangers. Newspapers cooperated with stories whose headlines read 'Electric Wire Slaughter' and 'Another Lineman Roasted to Death.' After the State of New York adopted electrocution using AC as its means of capital punishment, Edison officials referred to it as 'Westinghousing' the condemned."

"Then in 1892, Westinghouse's company won the competition to provide the lighting for the Chicago Columbian Exposition, proving to the world the safety and efficiency of AC power. That was the break that Westinghouse needed, and contracts to provide electricity to homes and businesses flooded Westinghouse Electric."

Throughout the twentieth century, AC transmission and distribution systems spread around the world and DC power, when required to operate something, was either provided through the use of a power-consuming transformer or by a relatively small DC storage device - a battery. In recent years, though, DC has been coming back into prominence.

- The major renewable energy technologies, photovoltaic solar and wind, produce DC power.

- DC-based options tend to be at the forefront of possibilities for local power storage.

- Microgrids, which produce, store and consume electricity locally, may be dominated by DC.

- Rapid charging of electric vehicles EVs with DC power is looking to be an important facilitator of EV acceptance. A number of previous Pike Research blog postings include discussions of this topic.

Another important trend has been the increasing importance of DC power within buildings This is especially true in offices for computers, monitors, servers and all of those other devices that have transformers. The transformers are those little bricks that convert the AC power coming from the outlet to the DC power that the devices require. These boxes feel warm to the touch because the conversion process is not totally efficient and some electricity is lost as heat.

In addition, lighting, the largest single use of electricity within buildings, is starting to move toward solid-state technology. LEDs are DC powered devices and the conversion of AC line power to DC involves some power loss.

A number of companies recognized this trend toward DC demand and, in 2008, joined together to form the EMerge Alliance. The Alliance's membership includes major energy service and product companies, as well as many of the major lighting and lighting control vendors. Hubbell, founded by the inventor of the original two-pin plug and socket, just recently joined. EMerge has two primary goals:

- Reduce or eliminate conversions where practical with AC-DC hybrid microgrids.

- Connect DC sources directly to DC loads.

The Alliance's mission is "developing standards leading to the rapid adoption of DC power distribution in commercial buildings." The standards would help eliminate much of the inefficient conversion of AC to DC between power sources and digital devices. The Alliance states that this will also facilitate the use of the most up-to-date, energy efficient products and controls by easing their installation.

One of the most intriguing drivers behind the work of the EMerge Alliance is the need to better integrate on-site renewable energy generation into the rest of the building's or campus' power supply. Normally, the solar photovoltaic or wind power is converted to AC by an inverter and fed into the local grid. Some installations have been designed to charge batteries, making the power available for later use, though the battery power is often converted to AC first. There are places where the solar PV or wind DC power is used directly to power DC devices such as large motors or drives, but this is only practical in a limited number of facilities that already are using a large amount of DC power.

In the EMerge Alliance vision, even an office building would be able to make direct use of on-site renewable energy. The Electrical Power Research Institute EPRI estimates the efficiency gain for use of on-site renewable energy without conversion to AC at 10-15 percent.

The EMerge Alliance's first standard, released during October 2009, defines a 24-volt DC microgrid for use in commercial interiors Occupied Space. A standard for Data Centers is under development and expected to be released during 2011. Other standards for Building Services larger building loads such as HVAC and industrial processes, and Outdoor outdoor lighting, signs and EV charging are also planned.

One of the EMerge Alliance's biggest challenges is overcoming the perceived safety issues associated with DC power an interesting twist from Edison's early attacks on AC. The specified use of class 2 circuits, as defined by the National Electrical Code, provides acceptable protection from electrical shock and fire hazards. In fact, such 24 Volt DC power is said to be significantly safer than the power at 120 Volt AC wall outlets.

Another approach to ensuring both safety and reliability has been to develop a list of EMerge Alliance Registered Products. The California Lighting Technology Center evaluates products to ensure compliance with the standard. The first registered products were announced at Greenbuild in November.

There have already been a number of installations using the Occupied Space standard, plus some pilots of the Data Center standard. The EMerge Alliance recently announced that Intel Labs is planning to install systems using both of these standards at its New Mexico Energy Systems Research Center. The project will include solar PV, a world-class PUE power usage effectiveness data center, energy storage, office lighting, and electric vehicle charging.

Over there in West Orange, New Jersey, the spirit of Thomas Edison is probably quite pleased.

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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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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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Crossrail will generate electricity using the wind created by trains

Urban Piezoelectric Energy Textiles capture wind-driven motion on tunnels, bridges, and facades, enabling renewable microgeneration for smart cities with decentralized power, resilient infrastructure, and flexible lamellae sheets that harvest airflow vibrations.

 

Key Points

Flexible piezoelectric sheets that convert urban wind and vibration into electricity on tunnels, bridges, and facades.

✅ Installed on London Crossrail to test airflow energy capture

✅ Flexible lamellae panels retrofit tunnels, bridges, facades

✅ Supports decentralized, resilient urban microgrids

 

Charlotte Slingsby and her startup Moya Power are researching piezo-electric textiles that gain energy from movement, similar to advances like a carbon nanotube energy harvester being explored by materials researchers. It seems logical that Slingsby originally came from a city with a reputation for being windy: “In Cape Town, wind is an energy source that you cannot ignore,” says the 27-year-old, who now lives in London.

Thanks to her home city, she also knows about power failures. That’s why she came up with the idea of not only harnessing wind as an alternative energy source by setting up wind farms in the countryside or at sea, but also for capturing it in cities using existing infrastructure.

 

The problem

The United Nations estimates that by 2050, two thirds of the world’s population will live in cities. As a result, the demand for energy in urban areas will increase dramatically, spurring interest in nighttime renewable technology that can operate when solar and wind are variable. Can the old infrastructure grow fast enough to meet demand? How might we decentralise power generation, moving it closer to the residents who need it?

For a pilot project, she has already installed grids of lamellae-covered plastic sheets in tunnels on London Crossrail routes; the draft in the tube causes the protrusions to flutter, which then generates electricity.

“If we all live in cities that need electricity, we need to look for new, creative ways to generate it, including nighttime solar cells that harvest radiative cooling,” says Slingsby, who studied design and engineering at Imperial College and the Royal College of Art. “I wanted to create something that works in different situations and that can be flexibly adapted, whether you live in an urban hut or a high-rise.”

The yield is low compared to traditional wind power plants and is not able to power whole cities, but Slingsby sees Moya Power as just a single element in a mixture of urban energy sources, alongside approaches like gravity power that aid grid decarbonization.

In the future, Slingsby’s invention could hang on skyscrapers, in tunnels or on bridges – capturing power in the windiest parts of the city, alongside emerging air-powered generators that draw energy from humidity. The grey concrete of tunnels and urban railway cuttings could become our cities’ most visually appealing surfaces...

 

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The Haves and Have-Nots of Electricity in California

California Public Safety Power Shutoffs highlight wildfire prevention as PG&E outages disrupt schools, businesses, and rural communities, driving generator use, economic hardship, and emergency preparedness across Northern California during high-wind events.

 

Key Points

Utility outages to reduce wildfire risk during extreme winds, impacting homes and businesses in high-risk California.

✅ PG&E cuts power during high winds to prevent wildfires

✅ Costs rise for generators, fuel, batteries, and spoiled food

✅ Rural, low-income communities face greater economic losses

 

The intentional blackout by California’s largest utility this week put Forest Jones out of work and his son out of school. On Friday morning Mr. Jones, a handyman and single father, sat in his apartment above a tattoo parlor waiting for the power to come back on and for school to reopen.

“I’ll probably lose $400 or $500 dollars because of this,” said Mr. Jones, who lives in the town of Paradise, which was razed by fire last year and is slowly rebuilding. “Things have been really tough up here.”

Millions of people were affected by the blackout, which spanned the outskirts of Silicon Valley to the forests of Humboldt County near the Oregon border. But the outage, which the power company said was necessary to reduce wildfire risk across the region, also drew a line between those who were merely inconvenienced and those who faced a major financial hardship.

To have the lights on, the television running and kitchen appliances humming is often taken for granted in America, even as U.S. grid during coronavirus questions persisted. During California’s blackout it became an economic privilege.

The economic impacts of the shut-off were especially acute in rural, northern towns like Paradise, where incomes are a fraction of those in the San Francisco Bay Area.

Both wealthy and poorer areas were affected by the blackout but interviews across the state suggested that being forced off the grid disproportionately hurt the less affluent. One family in Humboldt County said they had spent $150 on batteries and water alone during the shutdown.

“To be prepared costs money,” Sue Warhaftig, a massage therapist who lives in Mill Valley, a wealthy suburb across the Golden Gate Bridge from San Francisco. Ms. Warhaftig spent around two days without electricity but said she had been spared from significant sacrifices during the blackout.

She invested in a generator to keep the refrigerator running and to provide some light. She cooked in the family’s Volkswagen camper van in her driveway. At night she watched Netflix on her phone, which she was able to charge with the generator. Her husband, a businessman, is in London on a work trip. Her two sons, both grown, live in Southern California and Seattle.

“We were inconvenienced but life wasn’t interrupted,” Ms. Warhaftig said. “But so many people’s lives were.

Pacific Gas & Electric restored power to large sections of Northern California on Friday, including Paradise, where the electricity came back on in the afternoon. But hundreds of thousands of people in other areas remained in the dark. The carcasses of burned cars still littered the landscape around Paradise, where 86 people died in the Camp Fire last year, some of them while trying to escape.

Officials at power company said that by Saturday they hoped to have restored power to 98 percent of the customers who were affected.

The same dangerous winds that spurred the shut-off in Northern California have put firefighters to work in the south. The authorities in Los Angeles County ordered the evacuation of nearly 100,000 people on Friday as the Saddleridge Fire burned nearly 5,000 acres and destroyed 25 structures. The Sandalwood Fire, which ignited Thursday in Riverside County, had spread to more than 800 acres and destroyed 74 structures by Friday afternoon.

While this week’s outage was the first time many customers in Northern California experienced a deliberate power shut-off, residents in and around Paradise have had their power cut four times in recent months, residents say.

Many use a generator, but running one has become increasingly expensive with gasoline now at more than $4 a gallon in California.

On Friday, Dennis and Viola Timmer drove up the hill to their home in Magalia, a town adjacent to Paradise, loaded with $102 dollars of gasoline for their generators. It was their second gasoline run since the power went out Tuesday night.

The couple, retired and on a fixed income after Mr. Timmer’s time in the Navy and in construction, said the power outage had severely limited their ability to do essential tasks like cooking, or to leave the house.

“You know what it feels like? You’re in jail,” said Ms. Timmer, 72. “You can’t go anywhere with the generators running.”

Since the generators are not powerful enough to run heat or air conditioning, the couple slept in their den with an electric space heater.

“It’s really difficult because you don’t have a normal life,” Ms. Timmer said. “You’re trying to survive.”

To be sure, the shutdown has affected many people regardless of economic status, and similar disruptions abroad, like a London power outage that disrupted routines, show how widespread such challenges can be. The areas without power were as diverse as the wealthy suburbs of Silicon Valley, the old Gold Rush towns of the Sierra Nevada, the East Bay of San Francisco and the seaside city of Arcata.

Ms. Cahn’s cellphone ran out of power during the blackout and even when she managed to recharge it in her car cell service was spotty, as it was in many areas hit by the blackout.

Accustomed to staying warm at night with an electric blanket, Ms. Cahn slept under a stack of four blankets.

“I’m doing what I have to do which is not doing very much,” she said.

Further south in Marin City, Chanay Jackson stood surrounded by fumes from generators still powering parts of the city.

She said that food stamps were issued on the first of the month and that many residents who had to throw away food were out of luck.

“They’re not going to issue more food stamps just because the power went out,” Ms. Jackson said. “So they’re just screwed until next month.”

Strong winds have many times in the past caused power lines to come in contact with vegetation, igniting fires that are then propelled by the gusts, and hurricanes elsewhere have crippled infrastructure with Louisiana grid rebuild after Laura according to state officials. This was the case with the Camp Fire.

Since higher elevations had more extreme winds many of the neighborhoods where power was turned off this week were in hills and canyons, including in the Sierra Nevada.

The shut-off, which by one estimate affected a total of 2.5 million people, has come under strong criticism by residents and politicians, and warnings from Cal ISO about rolling blackouts as the power grid strained. The company’s website crashed just as customers sought information about the outage. Gov. Gavin Newsom called it unacceptable. But his comments were nuanced, criticizing the way the shut-off was handled, not the rationale for it. Mr. Newsom and others said the ravages of the Camp Fire demanded preventive action to prevent a reoccurrence.

Yet the calculus of trying to avoid deadly fires by shutting off power will continue to be debated as California enters its peak wildfire season, even as electricity reliability during COVID-19 was generally maintained for most consumers.

In the city of Grass Valley, Matthew Gottschalk said he and his wife realized that a generator was essential when they calculated that they had around $500 worth of food in their fridge.

“I don’t know what we would have done,” said Mr. Gottschalk, whose power went out Tuesday night.

His neighbors are filling coolers with ice. Everyone is hoping the power will come back on soon.

“Ice is going to run out and gas is going to run out,” he said.

 

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Scotland’s Wind Farms Generate Enough Electricity to Power Nearly 4.5 Million Homes

Scotland Wind Energy delivered record renewable power as wind turbines and farms generated 9,831,320 MWh in H1 2019, supplying clean electricity for every home twice and supporting northern England, according to WWF data.

 

Key Points

Term for Scotland's wind power output, highlighting 2019 records, clean electricity, and progress on decarbonization.

✅ 9,831,320 MWh generated Jan-Jun 2019 by wind farms

✅ Enough to power 4.47 million homes twice in that period

✅ Advances decarbonization and 2030 renewables, 2050 net-zero goals

 

Wind turbines in Scotland produced enough electricity in the first half of 2019, reflecting periods when wind led the power mix across the UK, to power every home in the country twice over, according to new data by the analytics group WeatherEnergy. The wind farms generated 9,831,320 megawatt-hours between January and June, as the UK set a wind generation record in comparable periods, equal to the total electricity consumption of 4.47 million homes during that same period.

The electricity generated by wind in early 2019 is enough to power all of Scotland’s homes, as well as a large portion of northern England’s, highlighting how wind and solar exceeded nuclear in the UK in recent milestones as well, and events such as record UK output during Storm Malik underscore this capacity.

“These are amazing figures,” Robin Parker, climate and energy policy manager at WWF, which highlighted the new data, said in a statement. “Scotland’s wind energy revolution is clearly continuing to power ahead, as wind became the UK’s main electricity source in a recent first. Up and down the country, we are all benefitting from cleaner energy and so is the climate.”

Scotland currently has a target of generating half its electricity from renewables by 2030, a goal buoyed by milestones like more UK electricity from wind than coal in 2016, and decarbonizing its energy system almost entirely by 2050. Experts say the latest wind energy data shows the country could reach its goal far sooner than originally anticipated, especially with complementary technologies such as tidal power in Scottish waters gaining traction.

 

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Investor: Hydro One has too many unknowns to be a good investment

Hydro One investment risk reflects Ontario government influence, board shakeup, Avista acquisition uncertainty, regulatory hearings, dividend growth prospects, and utility M&A moves in Peterborough, with stock volatility since the 2015 IPO.

 

Key Points

Hydro One investment risk stems from political control, governance turnover, regulatory outcomes, and uncertain M&A.

✅ Ontario retains near-50% stake, affecting autonomy and policy risk

✅ Board overhaul and CEO exit create governance uncertainty

✅ Avista deal, OEB hearings, local utility M&A drive outcomes

 

Hydro One may be only half-owned by the province on Ontario but that’s enough to cause uncertainty about the company’s future, thus making for an investment risk, says Douglas Kee of Leon Frazer & Associates.

Since its IPO in November of 2015, Hydro One has seen its share of ups and downs, including a Q2 profit decline earlier this year, mostly downs at this point. Currently trading at $19.87, the stock has lost 11 per cent of its value in 2018 and 12 per cent over the last 12 months, despite a one-time gain boosting Q2 profit that followed a court ruling.

This year has been a turbulent one, to say the least, as newly elected Ontario premier Doug Ford made good this summer on his campaign promise re Hydro One by forcing the resignation of the company’s 14-person board of directors along with the retirement of its chief executive, an event that saw Hydro One shares fall amid the turmoil. An interim CEO has been found and a new 10-person board and chairman put in place, but Kee says it’s unclear what impact the shakeup will ultimately have, other than delaying a promising-looking deal to purchase US utility Avista Corp, with the companies moving to ask the U.S. regulator to reconsider the order.

 

Douglas Kee’s take on Hydro One stock

“We looked at Hydro One a couple of times two years ago and just decided that with the Ontario government’s still owning a big chunk of the company … there are other public companies where you get the same kind of yield, the same kind of dividend growth, so we just avoided it,” says Kee, managing director and chief investment officer with Leon Frazer & Associates, to BNN Bloomberg.

“The old board versus the new board, I’m not sure that there’s much of an improvement. It was politics more than anything,” he says. “The unfortunate part is that the acquisition they were making in the United States is kind of on hold for now. The regulatory procedures have gone ahead but they are worried, and I guess the new board has to make a decision whether to go ahead with it or not.”

“Their transmissions side is coming up for regulatory hearings next year, which could be difficult in Ontario,” says Kee. “The offset to that is that there are a lot of municipal distributions systems in Ontario that may be sold — they bought one in Peterborough recently, which was a good deal for them. There may be more of that coming too.”

Last month, Hydro One reached an agreement with the City of Peterborough to buy its Peterborough Distribution utility which serves about 37,000 customers for $105 million. Another deal to purchase Orillia Power Distribution Corp for $41 million has been cancelled after an appeal to the Ontario Energy Board was denied in late August. Hydro One’s sought-after Avista Corp acquisition is reported to be worth $7 billion.

 

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