Duke Energy executives expect a slow economic recovery in 2010 and succeeding years, they told analysts in New York.
"We see the growth in (electrical) demand over the next five years being very, very anemic," CEO Jim Rogers said. Duke is the nation's third-largest, investor-owned utility.
Duke reported that its 2009 earnings were hurt by a 14 percent drop in sales to industries, although fourth-quarter sales stabilized.
"I would describe (industries') mood as cautiously optimistic in 2010," chief financial officer Lynn Good told a meeting of analysts, "although a significant rebound is not expected soon."
Customers are likely to see rising electric rates despite projections of a slow recovery, Duke said.
The company will spend $6 billion on four power plants now under construction, and expects to build more as old plants are shut down. New environmental rules are likely to cost another $5 billion.
Duke won approval last year for overall rate increases in the Carolinas. New rate requests in both states are likely in 2011, it said, with new rates in effect in 2012.
Duke expects earnings to grow 4 to 5 percent this year. Adjusted for one-time charges, earnings per share would grow of $1.25 to $1.30 a share, compared to $1.22 in 2009.
This year's revenue will grow $460 million from rate cases settled in the Carolinas and Midwest.
But high unemployment in its five-state territory — the Carolinas, Ohio, Kentucky and Indiana — will likely lead to essentially flat residential and commercial growth, executives said.
Good said it is "prudent to plan the year assuming 2010 will look like 2009."
As the recession lingers, Duke is pouring billions of dollars into new power plants.
A $2.4 billion expansion of the Cliffside power plant west of Charlotte, and construction of a new, $2.3 billion coal-fired plant in Edwardsport, Ind., are both about half finished.
New natural gas-fired units will be completed at its N.C. Buck and Dan River plants by 2011 and 2012.
Duke is seeking partners to build a new nuclear plant near Gaffney, S.C., but has pushed the expected completion date to 2021.
It's also considering a nuclear plant in Ohio, and will spend $1 billion to modernize its grid over the next five years.
A key priority, executives said, will be to more quickly recover its construction costs.
In North Carolina, that means persuading legislators to change the way Duke could recoup financing costs of a nuclear plant under construction. Duke wants to be able to recover those costs without filing a general rate case.
Duke said it expects tighter environmental rules for air pollutants, coal ash and carbon dioxide. Rogers, however, said he does not expect Congress to regulate greenhouse gases this year.
The more stringent rules are likely to cost the company $5 billion over a period of years. That's how much Duke spent to clean up its coal plants over the past decade.
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
✅ 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.
Agrivoltaics in Alberta integrates solar energy with agriculture, boosting crop yields and water conservation. The Strathmore Solar project showcases dual land use, sheep grazing for vegetation control, and PPAs that expand renewable energy capacity.
Key Points
A dual-use model where solar arrays and farming co-exist, boosting yields, saving water, and diversifying revenue.
✅ Strathmore Solar: 41 MW on 320 acres with managed sheep grazing
✅ 25-year TELUS PPA secures power and renewable energy credits
✅ Panel shade cuts irrigation needs and protects crops from extremes
Alberta is emerging as a leader in agrivoltaics—the innovative practice of integrating solar energy production with agricultural activities, aligning with the province's red-hot solar growth in recent years. This approach not only generates renewable energy but also enhances crop yields, conserves water, and supports sustainable farming practices. A notable example of this synergy is the Strathmore Solar project, a 41-megawatt solar farm located on 320 acres of leased industrial land owned by the Town of Strathmore. Operational since March 2022, it exemplifies how solar energy and agriculture can coexist and thrive together.
The Strathmore Solar Initiative
Strathmore Solar is a collaborative venture between Capital Power and the Town of Strathmore, with a 25-year power purchase agreement in place with TELUS Corporation for all the energy and renewable energy credits generated by the facility. The project not only contributes significantly to Alberta's renewable energy capacity, as seen with new solar facilities contracted at lower cost across the province, but also serves as a model for agrivoltaic integration. In a unique partnership, 400 to 600 sheep from Whispering Cedars Ranch are brought in to graze the land beneath the solar panels. This arrangement helps manage vegetation, reduce fire hazards, and maintain the facility's upkeep, all while providing shade for the grazing animals. This mutually beneficial setup maximizes land use efficiency and supports local farming operations, illustrating how renewable power developers can strengthen outcomes with integrated designs today.
Enhanced Crop Yields: Studies have shown that crops grown under solar panels can experience increased yields due to reduced water evaporation and protection from extreme weather conditions.
Water Conservation: The shade provided by solar panels helps retain soil moisture, leading to a decrease in irrigation needs.
Diversified Income Streams: Farmers can generate additional revenue by selling renewable energy produced by the solar panels back to the grid.
Sustainable Land Use: Agrivoltaics allows for dual land use, enabling the production of both food and energy without the need for additional land.
These benefits are evident in various agrivoltaic projects across Alberta, where farmers are successfully combining crop cultivation with solar energy production amid a renewable energy surge that is creating thousands of jobs.
Challenges and Considerations
While agrivoltaics presents numerous benefits, there are challenges to consider as Alberta navigates challenges with solar expansion today across Alberta:
Initial Investment: The setup costs for agrivoltaic systems can be high, requiring significant capital investment.
System Maintenance: Regular maintenance is essential to ensure the efficiency of both the solar panels and the agricultural operations.
Climate Adaptability: Not all crops may thrive under the conditions created by solar panels, necessitating careful selection of suitable crops.
Addressing these challenges requires careful planning, research, and collaboration between farmers, researchers, and energy providers.
Future Prospects
The success of projects like Strathmore Solar and other agrivoltaic initiatives in Alberta indicates a promising future for this dual-use approach. As technology advances and research continues, agrivoltaics could play a pivotal role in enhancing food security, promoting sustainable farming practices, and contributing to Alberta's renewable energy goals. Ongoing projects and partnerships aim to refine agrivoltaic systems, making them more efficient and accessible to farmers across the province.
The integration of solar energy production with agriculture in Alberta is not just a trend but a transformative approach to sustainable farming. The Strathmore Solar project serves as a testament to the potential of agrivoltaics, demonstrating how innovation can lead to mutually beneficial outcomes for both the agricultural and energy sectors.
Ontario Global Adjustment Charge faces constitutional scrutiny as a regulatory charge vs tax; Court of Appeal revives case over electricity pricing, feed-in tariff contracts, IESO policy, and hydro rate impacts on consumers and industry.
Key Points
A provincial electricity fee funding generator contracts, now central to a court fight over tax versus regulatory charge.
✅ Funds gap between market price and contracted generator rates
✅ At issue: regulatory charge vs tax under constitutional law
✅ Linked to feed-in tariff, IESO policy, and hydro rate hikes
Ontario’s court of appeal has decided that a constitutional challenge of a steep provincial electricity charge should get its day in court, overturning a lower-court judgment that had dismissed the legal bid.
Hamilton, Ont.-based National Steel Car Ltd. launched the challenge in 2017, saying Ontario’s so-called global adjustment charge was unconstitutional because it is a tax — not a valid regulatory charge — that was not passed by the legislature.
The global adjustment funds the difference between the province’s hourly electricity price and the price guaranteed under contracts to power generators. It is “the component that covers the cost of building new electricity infrastructure in the province, maintaining existing resources, as well as providing conservation and demand management programs,” the province’s Independent Electricity System Operator says.
However, the global adjustment now makes up most of the commodity portion of a household electricity bill, and its costs have ballooned, as regulators elsewhere consider a proposed 14% rate hike in Nova Scotia.
Ontario’s auditor general said in 2015 that global adjustment fees had increased from $650 million in 2006 to more than $7 billion in 2014. She added that consumers would pay $133 billion in global adjustment fees from 2015 to 2032, after having already paid $37 billion from 2006 to 2014.
National Steel Car, which manufactures steel rail cars and faces high electricity rates that hurt Ontario factories, said its global adjustment costs went from $207,260 in 2008 to almost $3.4 million in 2016, according to an Ontario Court of Appeal decision released on Wednesday.
The company claimed the global adjustment was a tax because one of its components funds electricity procurement contracts under a “feed-in tariff” program, or FIT, which National Steel Car called “the main culprit behind the dramatic price increases for electricity,” the decision said.
Ontario’s auditor general said the FIT program “paid excessive prices to renewable energy generators.” The program has been ended, but contracts awarded under it remain in place.
National Steel Car claimed the FIT program “was actually designed to accomplish social goals unrelated to the generation of electricity,” such as helping rural and indigenous communities, and was therefore a tax trying to help with policy goals.
“The appellant submits that the Policy Goals can be achieved by Ontario in several ways, just not through the electricity pricing formula,” the decision said.
National Steel Car also argued the global adjustment violated a provincial law that requires the government to hold a referendum for new taxes.
“The appellant’s principal claim is that the Global Adjustment was a ‘colourable attempt to disguise a tax as a regulatory charge with the purpose of funding the costs of the Policy Goals,’” the decision said. “The appellant pressed this argument before the motion judge and before this court. The motion judge did not directly or adequately address it.”
The Ontario government applied to have the challenge thrown out for having “no reasonable cause of action,” and a Superior Court judge did so in 2018, saying the global adjustment is not a tax.
National Steel Car appealed the decision, and the decision published Wednesday allowed the appeal, set aside the lower-court judgment, and will send the case back to Superior Court, where it could get a full hearing.
“The appellant’s claim is sufficiently plausible on the evidentiary record it put forward that the applications should not have been dismissed on a pleadings motion before the development of a full record,” wrote Justice Peter D. Lauwers. “It is not plain, obvious and beyond doubt that the Global Adjustment, and particularly the challenged component, is properly characterized as a valid regulatory charge and not as an impermissible tax.”
Jerome Morse of Morse Shannon LLP, one of National Steel Car’s lawyers, said the Ontario government would now have 60 days to decide whether to seek permission to appeal to the Supreme Court of Canada.
“What the court has basically said is, ‘this is a plausible argument, here are the reasons why it’s plausible, there was no answer to this,’” Morse told the Financial Post.
Ontario and the IESO had supported the lower-court decision, but there has been a change in government since the challenge was first launched, with Progressive Conservative Premier Doug Ford replacing the Liberals and Kathleen Wynne in power. The Liberals had launched a plan aimed at addressing hydro costs before losing in a 2018 election, the main thrust of which had been to refinance global adjustment costs.
Wednesday’s decision states that “Ontario’s counsel advised the court that the current Ontario government ‘does not agree with the former government’s electricity procurement policy (since-repealed).’
“The government’s view is that: ‘The solution does not lie with the courts, but instead in the political arena with political actors,’” it adds.
A spokesperson for Ontario Energy Minister Greg Rickford said in an email that they are reviewing the decision but “as this matter is in the appeal period, it would be inappropriate to comment.”
Ontario had also requested to stay the matter so a regulator, the Ontario Energy Board, could weigh in, while the Nova Scotia regulator approved a 14% hike in a separate case.
“However, Ontario only sought this relief from the motion judge in the alternative, and given the motion judge’s ultimate decision, she did not rule on the stay,” Thursday’s decision said. “It would be premature for this court to rule on the issue, although it seems incongruous for Ontario to argue that the Superior Court is the convenient forum in which to seek to dismiss the applications as meritless, but that it is not the convenient forum for assessing the merits of the applications.”
National Steel Car’s challenge bears a resemblance to the constitutional challenges launched by Ontario and other provinces over the federal government’s carbon tax, but Justice Lauwers wrote “that the federal legislative scheme under consideration in those cases is distinctly different from the legislation at issue in this appeal.”
“Nothing in those decisions impacts this appeal,” the judge added.
Hybrid renewable energy projects integrate wind, solar, and battery storage to enhance grid reliability, reduce curtailment, and provide dispatchable power in markets like Alberta, leveraging photovoltaic tracking, overbuilt transformers, and improved storage economics.
Key Points
Hybrid renewable energy projects combine wind, solar, and storage to deliver reliable, dispatchable clean power.
✅ Combine wind, solar, and batteries for steady, dispatchable output
✅ Lower curtailment by using shared transformers and smart inverters
✅ Boost farm income via leases; diversify risk from oil and gas
Third-generation farmer James Praskach has been burned by the oil and gas sector and watched wicked weather pound his crops flat, but he is hoping a new kind of energy -- the renewable kind -- will pay dividends.
The 39-year-old is part of a landowner consortium that is hosting the sprawling 300-megawatt Blackspring Ridge wind power project in southeastern Alberta.
He receives regular lease payments from the $600-million project that came online in 2014, even though none of the 166 towering wind turbines that surround his land are actually on it.
His lease payments stand to rise, however, when and if the proposed 77-MW Vulcan Solar project, which won regulatory approval in 2016, is green-lighted by developer EDF Renewables Inc.
The panels would cover about 400 hectares of his family's land with nearly 300,000 photovoltaic solar panels in Alberta, installed on racks designed to follow the sun. It would stand in the way of traditional grain farming of the land, but that wouldn't have been a problem this year, Praskach says.
"This year we actually had a massive storm roll through. And we had 100 per cent hail damage on all of (the Vulcan Solar lands). We had canola, peas and barley on it this year," he said, adding the crop was covered by insurance.
Meanwhile, poor natural gas prices and a series of oilpatch financial failures mean rents aren't being paid for about half of the handful of gas wells on his land, showing how a province that is a powerhouse for both fossil and green energy can face volatility -- he's appealed to the Alberta surface Rights Board for compensation.
"(Solar power) would definitely add a level of security for our farming operations," said Praskach.
Hybrid power projects that combine energy sources are a growing trend as selling renewable energy gains traction across markets. Solar only works during the day and wind only when it is windy so combining the two -- potentially with battery storage or natural gas or biomass generation -- makes the power profile more reliable and predictable.
Globally, an oft-cited example is on El Hierro, the smallest of the Canary Islands, where wind power is used to pump water uphill to a reservoir in a volcanic crater so that it can be released to provide hydroelectric power when needed. At times, the project has provided 100 per cent of the tiny island's energy needs.
Improvements in technology such as improving solar and wind power and lower costs for storage mean it is being considered as a hybrid add-on for nearly all of its renewable power projects, said Dan Cunningham, manager of business development at Greengate Power Corp. of Calgary.
Grant Arnold, CEO of developer BluEarth Renewables, agreed.
"The barrier to date, I would say, has been cost of storage but that is changing rapidly," he said. "We feel that wind and storage or solar and storage will be a fundamental way we do business within five years. It's changing very, very rapidly and it's the product everybody wants."
Vulcan Solar was proposed after Blackspring Ridge came online, said David Warner, associate director of business development for EDF Renewables, which now co-owns the wind farm with Enbridge Inc.
"Blackspring actually had incremental capacity in the main power transformers," he said. "Essentially, it was capable of delivering more energy than Blackspring was producing. It was overbuilt."
Vulcan Solar has been sized to utilize the shortfall without producing so much energy that either will ever have to be constrained, he said. Much of the required environmental work has already been done for the wind farm.
Storage is being examined as a potential addition to the project but implementing it depends on the regulatory system. At present, Alberta's regulators are still working on how to permit and control what they call "dispatchable renewables and storage" systems.
EDF announced last spring it would proceed with the Arrow Canyon Solar Project in Nevada which is to combine 200 MW of solar with 75 MW of battery storage by 2022 -- the batteries are to soak up the sun's power in the morning and dispatch the electricity in the afternoon when Las Vegas casinos' air conditioning is most needed.
What is clear is that renewable energy will continue to grow, with Alberta renewable jobs expected to follow -- in a recent report, the International Energy Agency said global electricity capacity from renewables is set to rise by 50 per cent over the next five years, an increase equivalent to adding the current total power capacity of the United States.
The share of renewables is expected to rise from 26 per cent now to 30 per cent in 2024 but will remain well short of what is needed to meet long-term climate, air quality and energy access goals, it added.
Ontario Poised to Miss 2030 Emissions Target highlights how rising greenhouse gas emissions from electricity generation and natural gas power plants threaten Ontario’s climate goals, environmental sustainability, and clean energy transition efforts amid growing economic and policy challenges.
Why is Ontario Poised to Miss 2030 Emissions Target?
Ontario Poised to Miss 2030 Emissions Target examines the province’s setback in meeting climate goals due to higher power-sector emissions and shifting energy policies.
✅ Rising greenhouse gas emissions from gas-fired electricity generation
✅ Climate policy uncertainty and missed environmental targets
✅ Balancing clean energy transition with economic pressures
Ontario’s path toward meeting its 2030 greenhouse gas emissions target has taken a sharp turn for the worse, according to internal government documents obtained by Global News. The province, once on track to surpass its reduction goals, is now projected to miss them—largely due to rising emissions from electricity generation, even as the IEA net-zero electricity report highlights rising demand nationwide.
In October 2024, the Ford government’s internal analysis indicated that Ontario was on track to reduce emissions by 28 percent below 2005 levels by 2030, effectively exceeding its target. But a subsequent update in January 2025 revealed a grim reversal. The new forecast showed an increase of about eight megatonnes (Mt) of emissions compared to the previous model, with most of the rise attributed to the province’s energy policies.
“This forecast is about 8 Mt higher than the October 2024 forecast, mainly due to higher electricity sector emissions that reflect the latest ENERGY/IESO energy planning and assumptions,” the internal document stated.
While the analysis did not specify which policy shifts triggered the change, experts point to Ontario’s growing reliance on natural gas. The use of gas-fired power plants has surged to fill temporary gaps created by nuclear refurbishment projects and other grid constraints, even as renewable energy’s role grows. In fact, natural gas generation in early 2025 reached its highest level since 2012.
The internal report cited “changing electricity generation,” nuclear power refurbishment, and “policy uncertainty” as major risks to achieving the province’s climate goals. But the situation may be even worse than the government’s updated forecast suggests.
On Wednesday, Ontario’s auditor general warned that the January projections were overly optimistic. The watchdog’s new report concluded the province could fall even further behind its 2030 emissions target, noting that reductions had likely been overestimated in several sectors, including transportation—such as electric vehicle sales—and waste management. “An even wider margin” of missed goals was now expected, the auditor said.
Environment Minister Todd McCarthy defended the government’s position, arguing that climate goals must be balanced against economic realities. “We cannot put families’ financial, household budgets at risk by going off in a direction that’s not achievable,” McCarthy said.
The minister declined to commit to new emissions targets beyond 2030—or even to confirm that the existing goals would be met—but insisted efforts were ongoing. “We are continuing to meet our commitment to at least try to meet our commitment for the 2030 target,” he told reporters. “But targets are not outcomes. We believe in achievable outcomes, not unrealistic objectives.”
Environmental advocates warn that Ontario’s reliance on fossil-fuel generation could lock the province into higher emissions for years, undermining national efforts to decarbonize Canada’s electricity grid. With cleaning up Canada’s electricity expected to play a central role in both industrial growth and climate action, the province’s backslide represents a significant setback for Canada’s overall emissions strategy.
As Ontario weighs its next steps, the tension between energy security, affordability, and environmental responsibility continues to define the province’s path toward a lower-carbon future and Canada’s 2050 net-zero target over the long term.
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.
