As Northern Illinois' frigid winter weather continues, ComEd has added to its CARE (Customers' Affordable Reliable Energy) Web site more energy-savings tips for electric space heat customers, whose electric usage dramatically increases during periods of extreme cold. ComEd also has added new energy-efficiency tips for renters.
"Everyone can take steps to reduce their energy use and lower their bills, no matter what type of home you have," said Anne Pramaggiore, senior vice president, ComEd regulatory and external affairs. "By providing customized energy-saving information and tips for electric space heaters and renters, we hope even more ComEd customers will embrace energy efficiency to save money and help protect our environment."
About 190,000 customers, or 6 percent of ComEd's residential customer base, use electricity as their primary source of heating for their home, rather than heating with natural gas. These electric space heat customers face a slightly higher annual average electric bill increase of roughly 28 percent over their past bills. During the winter months, these customers will see higher increases because the steep rate reduction they previously received for heating their homes with electricity is gradually being reduced. In the summer, these customers will experience a significantly lower increase.
Customers with electric space heat can particularly benefit from reducing their energy use during the winter heating season.
The http://www.ComEdCARE.com site, currently equipped with a variety of low- and no-cost tips and tools to help customers manage their energy usage, includes sections especially for electric space heat customers and renters. In fact, the ComEd Energy Doctor has responded to a number of questions from electric space heat customers, which are posted on the site.
ComEd CARE offers a number of energy-efficiency and low-income programs that can help customers reduce their bills as well as the residential rate stabilization plan, which allows residential customers the choice to pay for the rate increase over time. To access the new tips and more information on managing energy bills, customers can log on to http://www.ComEdCARE.com or call 888-806-CARE (2273).
Commonwealth Edison Company (ComEd) is a unit of Chicago-based Exelon Corporation , one of the nation's largest electric utilities with approximately 5.2 million customers and more than $15 billion in annual revenues. ComEd provides service to approximately 3.7 million customers across Northern Illinois, or 70 percent of the state's population.
France Electricity Crisis drives record power prices as nuclear outages squeeze supply, forcing energy imports, fuel oil and coal generation, amid gas market shocks, weak wind output, and freezing weather straining the grid.
Key Points
A French power shortfall from nuclear outages, record prices, heavy imports, and oil-fired backup amid cold weather.
✅ EDF halted reactors; 10% capacity offline, 30% by January
✅ Imports surge; fuel oil and coal units dispatched
✅ Prices spike as gas reverses flow and wind output drops
Electricity prices surged to a fresh record as France scrambled to keep its lights on, sucking up supplies from the rest of Europe.
France, usually an exporter of power, is boosting electricity imports and even burning fuel oil, and has at times limited nuclear output due to high river temperatures during heatwaves. The crunch comes after Electricite de France SA said it would halt four reactors accounting for 10% of the nation’s nuclear capacity, straining power grids already facing cold weather. Six oil-fired units were turned on in France on Tuesday morning, according to a filing with Entsoe.
“It’s illustrating how severe it is when they’re actually starting to burn fuel oil and importing from all these countries,” said Fabian Ronningen, an analyst at Rystad Energy. The unexpected plant maintenance “is reflected in the market prices,” he said
Europe is facing an energy crisis, with utilities relying on coal and oil. Almost 30% of France’s nuclear capacity will be offline at the beginning of January, leaving the energy market at the mercy of the weather. To make matters worse, Germany is closing almost half of its nuclear capacity before the end of the year, as Europe loses nuclear power just when it really needs energy.
German power for delivery next year surged 10% to 278.50 euros a megawatt-hour, while the French contract for January added 9.5% to a record 700.60 euros. Prices also gained, under Europe’s marginal pricing system, as gas jumped after shipments from Russia via a key pipeline reversed direction, flowing eastward toward Poland instead.
Neighboring countries are boosting their exports to France this week to cover for lost nuclear output, with imports from Germany rising to highest level in at least four years. In the U.K., four coal power units were operating on Tuesday with as much as 1.5 gigawatts of hourly output being sent across the channel.
The power crisis is so severe that the French government has asked EDF to restart some nuclear reactors earlier than planned amid outage risks for nuclear-powered France. Ecology Minister Barbara Pompili said last weekend that, in addition to the early reactor restarts and past river-temperature limits, the country had contracts with some companies in which they agreed to cut production during peak demand hours in exchange for payments from the government.
Higher energy prices threaten to derail Europe’s economic recovery just as the coronavirus omicron variety is spreading. Trafigura Group’s Nyrstar will pause production at its zinc smelter in France in the first week of January because of rising electricity prices. Norwegian fertilizer producer Yara International, which curbed output earlier this year, said it would continue to monitor the situation closely and curtail production where necessary.
Freezing weather this week is also sending short-term power prices surging as renewables can’t keep up, even though wind and solar overtook gas in the EU last year. German wind output plunged to a five-week low on Tuesday.
New England oil-fired generation surges as ISO New England manages a cold snap, dual-fuel switching, and a natural gas price spike, highlighting winter reliability challenges, LNG and pipeline limits, and rising CO2 emissions.
Key Points
Reliance on oil-burning power plants during winter demand spikes when natural gas is costly or constrained.
✅ Driven by dual-fuel switching amid high natural gas prices
✅ Raises CO2 emissions despite coal retirements and renewables growth
New England is relying on oil-fired generators for the most electricity since 2018 as a frigid blast boosts demand for power and natural gas prices soar across markets.
Oil generators were producing more than 4,200 megawatts early Thursday, accounting for about a quarter of the grid’s power supply, according to ISO New England. That was the most since Jan. 6, 2018, when oil plants produced as much as 6.4 gigawatts, or 32% of the grid’s output, said Wood Mackenzie analyst Margaret Cashman.
Oil is typically used only when demand spikes, because of higher costs and emissions concerns. Consumption has been consistently high over the past three weeks as some generators switch from gas, which has surged in price in recent months. New England generators are producing power from oil at an average rate of almost 1.8 gigawatts so far this month, the highest for January in at least five years.
Oil’s share declined to 16% Friday morning ahead of an expected snowstorm, which was “a surprise,” Cashman said.
“It makes me wonder if some of those generators are aiming to reserve their fuel for this weekend,” she said.
During the recent cold snap, more than a tenth of the electricity generated in New England has been produced by power plants that haven’t happened for at least 15 years.
Burning oil for electricity was standard practice throughout the region for decades. It was once our most common fuel for power and as recently as 2000, fully 19% of the six-state region’s electricity came from burning oil, according to ISO-New England, more than any other source except nuclear power at the time.
Since then, however, natural gas has gotten so cheap that most oil-fired plants have been shut or converted to burn gas, to the point that just 1% of New England’s electricity came from oil in 2018, whereas about half our power came from natural gas generation regionally during that period. This is good because natural gas produces less pollution, both particulates and greenhouse gasses, although exactly how much less is a matter of debate.
But as you probably know, there’s a problem: Natural gas is also used for heating, which gets first dibs. Prolonged cold snaps require so much gas to keep us warm, a challenge echoed in Ontario’s electricity system as supply tightens, that there might not be enough for power plants – at least, not at prices they’re willing to pay.
After we came close to rolling brownouts during the polar vortex in the 2017-18 winter because gas-fired power plants cut back so much, ISO-NE, which has oversight of the power grid, established “winter reliability” rules. The most important change was to pay power plants to become dual-fuel, meaning they can switch quickly between natural gas and oil, and to stockpile oil for winter cold snaps.
We’re seeing that practice in action right now, as many dual-fuel plants have switched away from gas to oil, just as was intended.
That switch is part of the reason EPA says the region’s carbon emissions have gone up in the pandemic, from 22 million tons of CO2 in 2019 to 24 million tons in 2021. That reverses a long trend caused partly by closing of coal plants and partly by growing solar and offshore wind capacity: New England power generation produced 36 million tons of CO2 a decade ago.
So if we admit that a return to oil burning is bad, and it is, what can we do in future winters? There are many possibilities, including tapping more clean imports such as Canadian hydropower to diversify supply.
The most obvious solution is to import more natural gas, especially from fracked fields in New York state and Pennsylvania. But efforts to build pipelines to do that have been shot down a couple of times and seem unlikely to go forward and importing more gas via ocean tanker in the form of liquefied natural gas (LNG) is also an option, but hits limits in terms of port facilities.
Aside from NIMBY concerns, the problem with building pipelines or ports to import more gas is that pipelines and ports are very expensive. Once they’re built they create a financial incentive to keep using natural gas for decades to justify the expense, similar to moves such as Ontario’s new gas plants that lock in generation. That makes it much harder for New England to decarbonize and potentially leaves ratepayers on the hook for a boatload of stranded costs.
Smart EV Charging orchestrates vehicle-to-grid (V2G), demand response, and fast charging to balance the power grid, integrating renewables, electrolyzers for hydrogen, and megawatt chargers for fleets with advanced control and co-optimization.
Key Points
Smart EV charging coordinates EV load to stabilize the grid, cut peaks, and integrate renewable energy efficiently.
✅ Reduces peak demand via coordinated, flexible load control
✅ Enables V2G services with renewables and battery storage
✅ Supports megawatt fast charging for heavy-duty fleets
As electric vehicle (EV) sales continue to rev up in the United States, the power grid is in parallel contending with the greatest transformation in its 100-year history: the large-scale integration of renewable energy and power electronic devices. The expected expansion of EVs will shift those challenges into high gear, causing cities to face gigawatt-growth in electricity demand, as analyses of EV grid impacts indicate, and higher amounts of variable energy.
Coordinating large numbers of EVs with the power system presents a highly complex challenge. EVs introduce variable electrical loads that are highly dependent on customer behavior. Electrified transportation involves co-optimization with other energy systems, like natural gas and bulk battery storage, including mobile energy storage flexibility for new operational options. It could involve fleets of automated ride-hailing EVs and lead to hybrid-energy truck stops that provide hydrogen and fast-charging to heavy-duty vehicles.
Those changes will all test the limits of grid integration, but the National Renewable Energy Laboratory (NREL) sees opportunity at the intersection of energy systems and transportation. With powerful resources for simulating and evaluating complex systems, several NREL projects are determining the coordination required for fast charging, balancing electrical supply and demand, and efficient use of all energy assets.
Smart and Not-So-Smart Control To appreciate the value of coordinated EV charging, it is helpful to imagine the opposite scenario.
"Our first question is how much benefit or burden the super simple, uncoordinated approach to electric vehicle charging offers the grid," said Andrew Meintz, the researcher leading NREL's Electric Vehicle Grid Integration team, as well as the RECHARGE project for smart EV charging. "Then we compare that to the 'whiz-bang,' everything-is-connected approach. We want to know the difference in value."
In the "super simple" approach, Meintz explained that battery-powered electric vehicles grow in market share, exemplified by mass-market EVs, without any evolution in vehicle charging coordination. Picture every employee at your workplace driving home at 5 p.m. and charging their vehicle. That is the grid's equivalent of going 0 to 100 mph, and if it does not wreck the system, it is at least very expensive. According to NREL's Electrification Futures Study, a comprehensive analysis of the impacts of widespread electrification across all U.S. economic sectors, in 2050 EVs could contribute to a 33% increase in energy use during peak electrical demand, underscoring state grid challenges that make these intervals costly when energy reserves are procured. In duck curve parlance, EVs will further strain the duck's neck.
The Optimization and Control Lab's Electric Vehicle Grid Integration bays allow researchers to determine how advanced high power chargers can be added safely and effectively to the grid, with the potential to explore how to combine buildings and EV charging. Credit: Dennis Schroeder, NREL Meintz's "whiz-bang" approach instead imagines EV control strategies that are deliberate and serve to smooth, rather than intensify, the upcoming demand for electricity. It means managing both when and where vehicles charge to create flexible load on the grid.
At NREL, smart strategies to dispatch vehicles for optimal charging are being developed for both the grid edge, where consumers and energy users connect to the grid, as in RECHARGEPDF, and the entire distribution system, as in the GEMINI-XFC projectPDF. Both projects, funded by the U.S. Department of Energy's (DOE's) Vehicle Technologies Office, lean on advanced capabilities at NREL's Energy Systems Integration Facility to simulate future energy systems.
At the grid edge, EVs can be co-optimized with distributed energy resources—small-scale generation or storage technologies—the subject of a partnership with Eaton that brought industry perspectives to bear on coordinated management of EV fleets.
At the larger-system level, the GEMINI-XFC project has extended EV optimization scenarios to the city scale—the San Francisco Bay Area, to be specific.
"GEMINI-XFC involves the highest-ever-fidelity modeling of transportation and the grid," said NREL Research Manager of Grid-Connected Energy Systems Bryan Palmintier.
"We're combining future transportation scenarios with a large metro area co-simulationPDF—millions of simulated customers and a realistic distribution system model—to find the best approaches to vehicles helping the grid."
GEMINI-XFC and RECHARGE can foresee future electrification scenarios and then insert controls that reduce grid congestion or offset peak demand, for example. Charging EVs involves a sort of shell game, where loads are continually moved among charging stations to accommodate grid demand.
But for heavy-duty vehicles, the load is harder to hide. Electrified truck fleets will hit the road soon, creating power needs for electric truck fleets that translate to megawatts of localized demand. No amount of rerouting can avoid the requirements of charging heavy-duty vehicles or other instances of extreme fast-charging (XFC). To address this challenge, NREL is working with industry and other national laboratories to study and demonstrate the technological buildout necessary to achieve 1+ MW charging stationsPDF that are capable of fast charging at very high energy levels for medium- and heavy-duty vehicles.
To reach such a scale, NREL is also considering new power conversion hardware based on advanced materials like wide-bandgap semiconductors, as well as new controllers and algorithms that are uniquely suited for fleets of charge-hungry vehicles. The challenge to integrate 1+ MW charging is also pushing NREL research to higher power: Upcoming capabilities will look at many-megawatt systems that tie in the support of other energy sectors.
Renewable In-Roads for Hydrogen
At NREL, the drive toward larger charging demands is being met with larger research capabilities. The announcement of ARIES opens the door to energy systems integration research at a scale 10-times greater than current capabilities: 20 MW, up from 2 MW. Critically, it presents an opportunity to understand how mobility with high energy demands can be co-optimized with other utility-scale assets to benefit grid stability.
"If you've got a grid humming along with a steady load, then a truck requires 500 kW or more of power, it could create a large disruption for the grid," said Keith Wipke, the laboratory program manager for fuel cells and hydrogen technologies at NREL.
Such a high power demand could be partially served by battery storage systems. Or it could be hidden entirely with hydrogen production. Wipke's program, with support from the DOE's Hydrogen and Fuel Cell Technologies Office, has been performing studies into how electrolyzers—devices that use electricity to break water into hydrogen and oxygen—could offset the grid impacts of XFC. These efforts are also closely aligned with DOE's H2@Scale vision for affordable and effective hydrogen use across multiple sectors, including heavy-duty transportation, power generation, and metals manufacturing, among others.
"We're simulating electrolyzers that can match the charging load of heavy-duty battery electric vehicles. When fast charging begins, the electrolyzers are ramped down. When fast charging ends, the electrolyzers are ramped back up," Wipke said. "If done smoothly, the utility doesn't even know it's happening."
NREL Researchers Rishabh Jain, Kazunori Nagasawa, and Jen Kurtz are working on how grid integration of electrolyzers—devices that use electricity to break water into hydrogen and oxygen—could offset the grid impacts of extreme fast-charging. Credit: National Renewable Energy Laboratory As electrolyzers harness the cheap electrons from off-demand periods, a significant amount of hydrogen can be produced on site. That creates a natural energy pathway from discount electricity into a fuel. It is no wonder, then, that several well-known transportation and fuel companies have recently initiated a multimillion-dollar partnership with NREL to advance heavy-duty hydrogen vehicle technologies.
"The logistics of expanding electric charging infrastructure from 50 kW for a single demonstration battery electric truck to 5,000 kW for a fleet of 100 could present challenges," Wipke said. "Hydrogen scales very nicely; you're basically bringing hydrogen to a fueling station or producing it on site, but either way the hydrogen fueling events are decoupled in time from hydrogen production, providing benefits to the grid."
The long driving range and fast refuel times—including a DOE target of achieving 10-minutes refuel for a truck—have already made hydrogen the standout solution for applications in warehouse forklifts. Further, NREL is finding that distributed electrolyzers can simultaneously produce hydrogen and improve voltage conditions, which can add much-needed stability to a grid that is accommodating more energy from variable resources.
Those examples that co-optimize mobility with the grid, using diverse technologies, are encouraging NREL and its partners to pursue a new scale of systems integration. Several forward-thinking projects are reimagining urban mobility as a mix of energy solutions that integrate the relative strengths of transportation technologies, which complement each other to fill important gaps in grid reliability.
The Future of Urban Mobility What will electrified transportation look like at high penetrations? A few NREL projects offer some perspective. Among the most experimental, NREL is helping the city of Denver develop a smart community, integrated with electrified mobility and featuring automated charging and vehicle dispatch.
On another path to advanced mobility, Los Angeles has embarked on a plan to modernize its electricity system infrastructure, reflecting California EV grid stability goals—aiming for a 100% renewable energy supply by 2045, along with aggressive electrification targets for buildings and vehicles. Through the Los Angeles 100% Renewable Energy Study, the city is currently working with NREL to assess the full-scale impacts of the transition in a detailed analysis that integrates diverse capabilities across the laboratory.
The transition would include the Port of Long Beach, the busiest container port in the United States.
At the port, NREL is applying the same sort of scenario forecasting and controls evaluation as other projects, in order to find the optimal mix of technologies that can be integrated for both grid stability and a reliable quality of service: a mix of hydrogen fuel-cell and battery EVs, battery storage systems, on-site renewable generation, and extreme coordination among everything.
"Hydrogen at ports makes sense for the same reason as trucks: Marine applications have big power and energy demands," Wipke said. "But it's really the synergies between diverse technologies—the existing infrastructure for EVs and the flexibility of bulk battery systems—that will truly make the transition to high renewable energy possible."
Like the Port of Long Beach, transportation hubs across the nation are adapting to a complex environment of new mobility solutions. Airports and public transit stations involve the movement of passengers, goods, and services at a volume exceeding anywhere else. With the transition to digitally connected electric mobility changing how airports plan for the future, NREL projects such as Athena are using the power of high-performance computing to demonstrate how these hubs can maximize the value of passenger and freight mobility per unit of energy, time, and/or cost.
The growth in complexity for transportation hubs has just begun, however. Looking ahead, fleets of ride-sharing EVs, automated vehicles, and automated ride-sharing EV fleets could present the largest effort to manage mobility yet.
A Self-Driving Power Grid To understand the full impact of future mobility-service providers, NREL developed the HIVE (Highly Integrated Vehicle Ecosystem) simulation framework. HIVE combines factors related to serving mobility needs and grid operations—such as a customer's willingness to carpool or delay travel, and potentially time-variable costs of recharging—and simulates the outcome in an integrated environment.
"Our question is, how do you optimize the management of a fleet whose primary purpose is to provide rides and improve that fleet's dispatch and charging?" said Eric Wood, an NREL vehicle systems engineer.
HIVE was developed as part of NREL's Autonomous Energy Systems research to optimize the control of automated vehicle fleets. That is, optimized routing and dispatch of automated electric vehicles.
The project imagines how price signals could influence dispatch algorithms. Consider one customer booking a commute through a ride-hailing app. Out of the fleet of vehicles nearby—variously charged and continually changing locations—which one should pick up the customer?
Now consider the movements of thousands of passengers in a city and thousands of vehicles providing transportation services. Among the number of agents, the moment-to-moment change in energy supply and demand, and the broad diversity in vendor technologies, "we're playing with a lot of parameters," Wood said.
But cutting through all the complexity, and in the midst of massive simulations, the end goal for vehicle-to-grid integration is consistent:
"The motivation for our work is that there are forecasts for significant load on the grid from the electrification of transportation," Wood said. "We want to ensure that this load is safely and effectively integrated, while meeting the expectations and needs of passengers."
The Port of Long Beach uses a mix of hydrogen fuel-cell and battery EVs, battery storage systems, on-site renewable generation, and extreme coordination among everything. Credit: National Renewable Energy Laboratory True Replacement without Caveats
Electric vehicles are not necessarily helpful to the grid, but they can be. As EVs become established in the transportation sector, NREL is studying how to even out any bumps that electrified mobility could cause on the grid and advance any benefits to commuters or industry.
"It all comes down to load flexibility," Meintz said. "We're trying to decide how to optimally dispatch vehicle charging to meet quality-of-service considerations, while also minimizing charging costs."
BC Hydro COVID-19 Bill Relief provides payment deferrals, no-penalty payment plans, Crisis Fund grants up to $600, and utility bill assistance as customers face pandemic layoffs, social distancing, and increased home power usage.
Key Points
A BC Hydro program offering bill deferrals, no-penalty plans, and up to $600 Crisis Fund grants during COVID-19.
✅ Defer payments or set no-penalty payment plans
✅ Apply for up to $600 Customer Crisis Fund grants
✅ Measures to ensure reliable power and remote customer service
BC Hydro is implementing a program, including bill relief measures, to help people pay their bills if they’re affected by the novel coronavirus.
The Crown corporation says British Columbians are facing a variety of financial pressures related to the COVID-19 pandemic, as some workplaces close or reduce staffing levels and commercial power consumption plummets across the province.
BC Hydro said it also expects increased power usage as more people stay home amid health officials’ requests that people take social distancing measures, even as electricity demand is down 10% provincewide.
Under the new program, customers will be able to defer bill payments or arrange a payment plan with no penalty, though a recent report on deferred operating costs outlines long-term implications for the utility.
BC Hydro says some customers could also be eligible for grants of up to $600 under its Customer Crisis Fund, if facing power disconnection due to job loss, illness or loss of a family member, while in other jurisdictions power bills were cut for households during the pandemic.
The company says it has taken precautions to keep power running by isolating key facilities, including its control centre, and by increasing its cleaning schedule, a priority even as some utilities face burgeoning debt amid COVID-19.
It has also closed its walk-in customer service desks to reduce risk from face-to-face contact and suspended all non-essential business travel, public meetings and site tours, and warned businesses about BC Hydro impersonation scams during this period.
DOE RMUC Cybersecurity Program supports rural, municipal, and small investor-owned utilities with grants, technical assistance, grid resilience, incident response, workforce training, and threat intelligence sharing to harden energy systems and protect critical infrastructure.
Key Points
A $250M DOE program providing grants to boost rural and municipal utilities' cybersecurity and incident response.
✅ Grants and technical assistance for grid security
✅ Enhances incident response and threat intel sharing
✅ Builds cybersecurity workforce in rural utilities
The U.S. Department of Energy (DOE) today issued a Request for Information (RFI) seeking public input on a new $250 million program to strengthen the cybersecurity posture of rural, municipal, and small investor-owned electric utilities.
Funded by President Biden’s Bipartisan Infrastructure Law and broader clean energy funding initiatives, the Rural and Municipal Utility Advanced Cybersecurity Grant and Technical Assistance (RMUC) Program will help eligible utilities harden energy systems, processes, and assets; improve incident response capabilities; and increase cybersecurity skills in the utility workforce. Providing secure, reliable power to all Americans, with a focus on equity in electricity regulation across communities, will be a key focus on the pathway to achieving President Biden’s goal of a net-zero carbon economy by 2050.
“Rural and municipal utilities provide power for a large portion of low- and moderate-income families across the nation and play a critical role in ensuring the economic security of our nation’s energy supply,” said U.S. Secretary of Energy Jennifer M. Granholm. “This new program reflects the Biden Administration's commitment to improving energy reliability and connecting our nation’s rural communities to resilient energy infrastructure and the transformative benefits that come with it.”
Nearly one in six Americans live in a remote or rural community. Utilities in these communities face considerable obstacles, including difficulty recruiting top cybersecurity talent, inadequate infrastructure, as the aging U.S. power grid struggles to support new technologies, and lack of financial resources needed to modernize and harden their systems.
The RMUC Program will provide financial and technical assistance to help rural, municipal, and small investor-owned electric utilities improve operational capabilities, increase access to cybersecurity services, deploy advanced cyber security technologies, and increase participation of eligible entities in cybersecurity threat information sharing programs and coordination with federal partners initiatives. Priority will be given to eligible utilities that have limited cybersecurity resources, are critical to the reliability of the bulk power system, or those that support our national defense infrastructure.
The Office of Cybersecurity, Energy Security, and Emergency Response (CESER), which advances U.S. energy security objectives, will manage the RMUC Program, providing $250 million dollars in BIL funding over five years. To help inform Program implementation, DOE is seeking input from the cybersecurity community, including eligible utilities and representatives of third parties and organizations that support or interact with these utilities. The RFI seeks input on ways to improve cybersecurity incident preparedness, response, and threat information sharing; cybersecurity workforce challenges; risks associated with technologies deployed on the electric grid; national-scale initiatives to accelerate cybersecurity improvements in these utilities; opportunities to strengthen partnerships and energy security support efforts; the selection criteria and application process for funding awards; and more.
Boeing 787 More-Electric Architecture replaces pneumatics with bleedless pressurization, VFSG starter-generators, electric brakes, and heated wing anti-ice, leveraging APU, RAT, batteries, and airport ground power for efficient, redundant electrical power distribution.
Key Points
An integrated, bleedless electrical system powering start, pressurization, brakes, and anti-ice via VFSGs, APU and RAT.
✅ VFSGs start engines, then generate 235Vac variable-frequency power
✅ Bleedless pressurization, electric anti-ice improve fuel efficiency
✅ Electric brakes cut hydraulic weight and simplify maintenance
The 787 Dreamliner is different to most commercial aircraft flying the skies today. On the surface it may seem pretty similar to the likes of the 777 and A350, but get under the skin and it’s a whole different aircraft.
When Boeing designed the 787, in order to make it as fuel efficient as possible, it had to completely shake up the way some of the normal aircraft systems operated. Traditionally, systems such as the pressurization, engine start and wing anti-ice were powered by pneumatics. The wheel brakes were powered by the hydraulics. These essential systems required a lot of physical architecture and with that comes weight and maintenance. This got engineers thinking.
What if the brakes didn’t need the hydraulics? What if the engines could be started without the pneumatic system? What if the pressurisation system didn’t need bleed air from the engines? Imagine if all these systems could be powered electrically… so that’s what they did.
Power sources
The 787 uses a lot of electricity. Therefore, to keep up with the demand, it has a number of sources of power, much as grid operators track supply on the GB energy dashboard to balance loads. Depending on whether the aircraft is on the ground with its engines off or in the air with both engines running, different combinations of the power sources are used.
Engine starter/generators
The main source of power comes from four 235Vac variable frequency engine starter/generators (VFSGs). There are two of these in each engine. These function as electrically powered starter motors for the engine start, and once the engine is running, then act as engine driven generators.
The generators in the left engine are designated as L1 and L2, the two in the right engine are R1 and R2. They are connected to their respective engine gearbox to generate electrical power directly proportional to the engine speed. With the engines running, the generators provide electrical power to all the aircraft systems.
APU starter/generators
In the tail of most commercial aircraft sits a small engine, the Auxiliary Power Unit (APU). While this does not provide any power for aircraft propulsion, it does provide electrics for when the engines are not running.
The APU of the 787 has the same generators as each of the engines — two 235Vac VFSGs, designated L and R. They act as starter motors to get the APU going and once running, then act as generators. The power generated is once again directly proportional to the APU speed.
The APU not only provides power to the aircraft on the ground when the engines are switched off, but it can also provide power in flight should there be a problem with one of the engine generators.
Battery power
The aircraft has one main battery and one APU battery. The latter is quite basic, providing power to start the APU and for some of the external aircraft lighting.
The main battery is there to power the aircraft up when everything has been switched off and also in cases of extreme electrical failure in flight, and in the grid context, alternatives such as gravity power storage are being explored for long-duration resilience. It provides power to start the APU, acts as a back-up for the brakes and also feeds the captain’s flight instruments until the Ram Air Turbine deploys.
Ram air turbine (RAT) generator
When you need this, you’re really not having a great day. The RAT is a small propeller which automatically drops out of the underside of the aircraft in the event of a double engine failure (or when all three hydraulics system pressures are low). It can also be deployed manually by pressing a switch in the flight deck.
Once deployed into the airflow, the RAT spins up and turns the RAT generator. This provides enough electrical power to operate the captain’s flight instruments and other essentials items for communication, navigation and flight controls.
External power
Using the APU on the ground for electrics is fine, but they do tend to be quite noisy. Not great for airports wishing to keep their noise footprint down. To enable aircraft to be powered without the APU, most big airports will have a ground power system drawing from national grids, including output from facilities such as Barakah Unit 1 as part of the mix. Large cables from the airport power supply connect 115Vac to the aircraft and allow pilots to shut down the APU. This not only keeps the noise down but also saves on the fuel which the APU would use.
The 787 has three external power inputs — two at the front and one at the rear. The forward system is used to power systems required for ground operations such as lighting, cargo door operation and some cabin systems. If only one forward power source is connected, only very limited functions will be available.
The aft external power is only used when the ground power is required for engine start.
Circuit breakers
Most flight decks you visit will have the back wall covered in circuit breakers — CBs. If there is a problem with a system, the circuit breaker may “pop” to preserve the aircraft electrical system. If a particular system is not working, part of the engineers procedure may require them to pull and “collar” a CB — placing a small ring around the CB to stop it from being pushed back in. However, on the 787 there are no physical circuit breakers. You’ve guessed it, they’re electric.
Within the Multi Function Display screen is the Circuit Breaker Indication and Control (CBIC). From here, engineers and pilots are able to access all the “CBs” which would normally be on the back wall of the flight deck. If an operational procedure requires it, engineers are able to electrically pull and collar a CB giving the same result as a conventional CB.
Not only does this mean that the there are no physical CBs which may need replacing, it also creates space behind the flight deck which can be utilised for the galley area and cabin.
A normal flight
While it’s useful to have all these systems, they are never all used at the same time, and, as the power sector’s COVID-19 mitigation strategies showed, resilience planning matters across operations. Depending on the stage of the flight, different power sources will be used, sometimes in conjunction with others, to supply the required power.
On the ground
When we arrive at the aircraft, more often than not the aircraft is plugged into the external power with the APU off. Electricity is the blood of the 787 and it doesn’t like to be without a good supply constantly pumping through its system, and, as seen in NYC electric rhythms during COVID-19, demand patterns can shift quickly. Ground staff will connect two forward external power sources, as this enables us to operate the maximum number of systems as we prepare the aircraft for departure.
Whilst connected to the external source, there is not enough power to run the air conditioning system. As a result, whilst the APU is off, air conditioning is provided by Preconditioned Air (PCA) units on the ground. These connect to the aircraft by a pipe and pump cool air into the cabin to keep the temperature at a comfortable level.
APU start
As we near departure time, we need to start making some changes to the configuration of the electrical system. Before we can push back , the external power needs to be disconnected — the airports don’t take too kindly to us taking their cables with us — and since that supply ultimately comes from the grid, projects like the Bruce Power upgrade increase available capacity during peaks, but we need to generate our own power before we start the engines so to do this, we use the APU.
The APU, like any engine, takes a little time to start up, around 90 seconds or so. If you remember from before, the external power only supplies 115Vac whereas the two VFSGs in the APU each provide 235Vac. As a result, as soon as the APU is running, it automatically takes over the running of the electrical systems. The ground staff are then clear to disconnect the ground power.
If you read my article on how the 787 is pressurised, you’ll know that it’s powered by the electrical system. As soon as the APU is supplying the electricity, there is enough power to run the aircraft air conditioning. The PCA can then be removed.
Engine start
Once all doors and hatches are closed, external cables and pipes have been removed and the APU is running, we’re ready to push back from the gate and start our engines. Both engines are normally started at the same time, unless the outside air temperature is below 5°C.
On other aircraft types, the engines require high pressure air from the APU to turn the starter in the engine. This requires a lot of power from the APU and is also quite noisy. On the 787, the engine start is entirely electrical.
Power is drawn from the APU and feeds the VFSGs in the engines. If you remember from earlier, these fist act as starter motors. The starter motor starts the turn the turbines in the middle of the engine. These in turn start to turn the forward stages of the engine. Once there is enough airflow through the engine, and the fuel is igniting, there is enough energy to continue running itself.
After start
Once the engine is running, the VFSGs stop acting as starter motors and revert to acting as generators. As these generators are the preferred power source, they automatically take over the running of the electrical systems from the APU, which can then be switched off. The aircraft is now in the desired configuration for flight, with the 4 VFSGs in both engines providing all the power the aircraft needs.
As the aircraft moves away towards the runway, another electrically powered system is used — the brakes. On other aircraft types, the brakes are powered by the hydraulics system. This requires extra pipe work and the associated weight that goes with that. Hydraulically powered brake units can also be time consuming to replace.
By having electric brakes, the 787 is able to reduce the weight of the hydraulics system and it also makes it easier to change brake units. “Plug in and play” brakes are far quicker to change, keeping maintenance costs down and reducing flight delays.
In-flight
Another system which is powered electrically on the 787 is the anti-ice system. As aircraft fly though clouds in cold temperatures, ice can build up along the leading edge of the wing. As this reduces the efficiency of the the wing, we need to get rid of this.
Other aircraft types use hot air from the engines to melt it. On the 787, we have electrically powered pads along the leading edge which heat up to melt the ice.
Not only does this keep more power in the engines, but it also reduces the drag created as the hot air leaves the structure of the wing. A double win for fuel savings.
Once on the ground at the destination, it’s time to start thinking about the electrical configuration again. As we make our way to the gate, we start the APU in preparation for the engine shut down. However, because the engine generators have a high priority than the APU generators, the APU does not automatically take over. Instead, an indication on the EICAS shows APU RUNNING, to inform us that the APU is ready to take the electrical load.
Shutdown
With the park brake set, it’s time to shut the engines down. A final check that the APU is indeed running is made before moving the engine control switches to shut off. Plunging the cabin into darkness isn’t a smooth move. As the engines are shut down, the APU automatically takes over the power supply for the aircraft. Once the ground staff have connected the external power, we then have the option to also shut down the APU.
However, before doing this, we consider the cabin environment. If there is no PCA available and it’s hot outside, without the APU the cabin temperature will rise pretty quickly. In situations like this we’ll wait until all the passengers are off the aircraft until we shut down the APU.
Once on external power, the full flight cycle is complete. The aircraft can now be cleaned and catered, ready for the next crew to take over.
Bottom line
Electricity is a fundamental part of operating the 787. Even when there are no passengers on board, some power is required to keep the systems running, ready for the arrival of the next crew. As we prepare the aircraft for departure and start the engines, various methods of powering the aircraft are used.
The aircraft has six electrical generators, of which only four are used in normal flights. Should one fail, there are back-ups available. Should these back-ups fail, there are back-ups for the back-ups in the form of the battery. Should this back-up fail, there is yet another layer of contingency in the form of the RAT. A highly unlikely event.
The 787 was built around improving efficiency and lowering carbon emissions whilst ensuring unrivalled levels safety, and, in the wider energy landscape, perspectives like nuclear beyond electricity highlight complementary paths to decarbonization — a mission it’s able to achieve on hundreds of flights every single day.
