South Africa's 5,000-megawatt MW mega-solar power project is progressing toward the first phase of construction, and Fluor South Africa, which is a division of Fluor Corporation, is developing a conceptual master plan.
The project's base will be in the town of Upington, which is on the banks of the Orange River in the Northern Cape. The river traces a fertile agricultural ribbon through an area close to the Kalahari Desert.
State-owned power utility Eskom has plans to supply the necessary 400-kilovolt kV infrastructure by 2012 to provide transmission for 1,500 MW of power. The specific power additions during the phases of construction will not be confirmed until the publication of the master plan. Eskom has said that meeting all the environmental impact assessment EIA requirements could take as long as seven years. Four long transmission lines would carry the power to the national grid from the solar park. Eskom already has applied for the EIAs, and now will have to move on approvals from landowners. But the utility has plans to build transformers by 2014 and two further 400-kV lines by 2016. The development of the first 1,500 MW will be incremental and could be reached by 2016/17, when Eskom will build two more 400-kV lines.
Upington has one of the highest levels of solar radiation in the country and receives about 8.17 kilowatt-hours kWh per square meter per day. The $20 billion project is already spawning solar manufacturing projects, which will serve the solar park corridor and be available for other projects nationally.
Renewable energy company Solairedirect has plans for the production of roof-integrated solar photovoltaic PV modules. Suntech Power Holdings, China's largest maker of solar panels and the world's largest crystalline silicon PV module manufacturer, has signed a memorandum of understanding with the local Umsimbithi Holdings to develop a 100-MW solar energy plant. China's Yingli Solar is developing a 10-MW solar project in the Northern Cape, which will expand to 100 MW. By the end of 2012, Italy's Italgest Energia will be operating a PV panel factory with an initial capacity of 110 MW. Eskom will use a portion of its $3.75 billion World Bank loan to build a 100-MW concentrated-solar power plant, which will be incorporated into the Upington project.
Multiple solar technologies are now favored for the $21 billion project they include PV, concentrated PV, concentrated solar power, and variations as this would assist in the development of a solar industry in South Africa.
Fluor, which is already a central player in the project as the concept planner, will need the inside track position for the overall engineering, procurement, construction and management EPCM contract, when it comes, as the company could bring a wide range of experience of the total supply chain of renewable projects. It is currently working on solar power projects in other countries.
German Energy Price Brakes harness price signals in a market-based policy, cutting gas consumption, preserving industrial output, and supporting CO2 reduction, showcasing Germany's resilience and adaptation while protecting households and businesses across Europe.
Key Points
Fixed-amount subsidies preserving price signals to curb gas use, shield consumers, and sustain industrial output.
✅ Maintains incentives via market-based price signals
✅ Cuts gas consumption without distorting EU markets
✅ Protects households and industry while curbing CO2
German industry and society are once again proving much more resilient and adaptable than certain people feared. Horror scenarios of a dangerous energy rationing or a massive slump in our economy have often been bandied about. But we are nowhere near that. With a challenging year just behind us, this is good news — not only for Germany, but also for Europe, where France-Germany energy cooperation has strengthened solidarity.
Companies and households reacted swiftly to the sharp increases in energy prices, in line with momentum in the global energy transition seen across markets. They installed more efficient heating or production facilities, switched to alternatives and imported intermediate products. The results are encouraging: German households and businesses have reduced gas consumption significantly, despite recent cold weather. From the start of the war in Ukraine to mid-December industrial gas consumption in Germany was (temperature-adjusted) around 20 per cent lower than the average level for the preceding three years. Even if some firms have cut back production, especially in energy-intensive sectors, industrial output as a whole has only fallen by about 1 per cent since the start of 2022. Added to this, in a survey released by the Ifo institute in November, over a third of German companies saw the potential to reduce gas consumption further without endangering output.
Instead of imposing excessive laws and regulations, we have relied on price signals and the prudence of market participants to create the right incentives and reduce gas consumption, as falling costs like record-low solar power prices continue to reinforce those signals across sectors.
We will follow this approach in coming months, when energy savings will remain important, even as the EU electricity outlook anticipates sharply higher demand by 2050. Our latest relief measures will not distort price signals. To this end, the Bundestag approved gas and electricity price brakes in its final session in 2022. They are designed to function without any intervention in markets or prices. This system will pay out a fixed amount relative to previous years’ consumption and the current difference to a reference price — regardless of current consumption.
Energy price brakes are the main component of Germany’s “protective shield”, which makes up to €200bn available for measures in 2022 to 2024. Seen in relation to the German economy’s size, its past heavy reliance on Russian energy imports and the fact that the measures will expire in 2024, these are balanced and expedient mechanisms. In contrast to instruments used in other countries, our new arrangements will not affect the price formation process driven by supply and demand, or on incentives to save gas. Companies and households will continue to save the full market price when they reduce consumption by a unit of gas or electricity. In this way, the price brakes also avoid the creation of additional demand for gas at the expense of consumers in other European countries, even as Europe’s Big Oil turning electric signals broader structural shifts in energy markets. No one need fear that competition will be distorted or that gas will be bought up. Indeed, a recent IMF working paper on cushioning the impact of high energy prices on households explicitly praises the German energy price brakes.
Current developments confirm the effectiveness of a market-based approach — and show that we should also rely on price signals when it comes to reducing CO₂ emissions, as suggested by IEA CO2 trends in recent years. Last year, households and companies had only a few weeks to adapt, yet we have already seen a strong response. The effect of CO₂ prices can be even stronger, as adaptation is possible over a much longer time and they additionally affect expectations and long-term decisions. Regulatory interventions and subsidy schemes, even if well targeted, cannot compete with market co-ordination and incentives that support individual decision-making and promote innovation.
Europe and Germany can weather this crisis without a collapse in industrial production. We also have an opportunity to deal efficiently with the move to climate neutrality, aligned with Germany’s hydrogen strategy for imported low-carbon fuels. In both cases, we should have confidence in price signals as well as in the power of people and business to innovate and adapt.
Ukraine Electricity Exports resume as the EU grid links stabilize; ENTSO-E caps, megawatt capacity, renewables, and infrastructure repairs enable power flows to Moldova, Poland, Slovakia, and Romania despite ongoing Russian strikes.
Key Points
Resumed cross-border power sales showing grid stability under ENTSO-E limits and surplus generation.
✅ Exports restart to Moldova; Poland, Slovakia, Romania next.
✅ ENTSO-E cap limits to 400 MW; more capacity under negotiation.
✅ Revenues fund grid repairs after Russian strikes.
Ukraine began resuming electricity exports to European countries on Tuesday, its energy minister said, a dramatic turnaround from six months ago when fierce Russian bombardment of power stations plunged much of the country into darkness in a bid to demoralize the population.
The announcement by Energy Minister Herman Halushchenko that Ukraine was not only meeting domestic consumption demands but also ready to restart exports to its neighbors was a clear message that Moscow’s attempt to weaken Ukraine by targeting its infrastructure did not work.
Ukraine’s domestic energy demand is “100%” supplied, he told The Associated Press in an interview, and it has reserves to export due to the “titanic work” of its engineers and international partners.
Russia ramped up infrastructure attacks in September, when waves of missiles and exploding drones destroyed about half of Ukraine's energy system, even as it built lines to reactivate the Zaporizhzhia plant in occupied territory. Power cuts were common across the country as temperatures dropped below freezing and tens of millions struggled to keep warm.
Moscow said the strikes were aimed at weakening Ukraine’s ability to defend itself, and both sides have floated a possible agreement on power plant attacks amid mounting civilian harm, while Western officials said the blackouts that caused civilians to suffer amounted to war crimes. Ukrainians said the timing was designed to destroy their morale as the war marked its first anniversary.
Ukraine had to stop exporting electricity in October to meet domestic needs.
Engineers worked around the clock, often risking their lives to come into work at power plants and keep the electricity flowing. Kyiv’s allies also provided help. In December, U.S. Secretary of State Antony Blinken announced $53 million in bilateral aid to help the country acquire electricity grid equipment, on top of $55 million for energy sector support.
Much more work remains to be done, Halushchenko said. Ukraine needs funding to repair damaged generation and transmission lines, and revenue from electricity exports would be one way to do that.
The first country to receive Ukraine’s energy exports will be Moldova, he said.
Besides the heroic work by engineers and Western aid, warmer temperatures are enabling the resumption of exports by making domestic demand lower, and across Europe initiatives like virtual power plants for homes are helping balance grids. Nationwide consumption was already down at least 30% due to the war, Halushchenko said, with many industries having to operate with less power.
Renewables like solar and wind power also come into play as temperatures rise, taking some pressure off nuclear and coal-fired power plants.
But it’s unclear if Ukraine can keep up exports amid the constant threat of Russian bombardment.
“Unfortunately now a lot of things depend on the war,” Halushchenko said. “I would say we feel quite confident now until the next winter.”
Exports to Poland, Slovakia and Romania are also on schedule to resume, he said.
“Today we are starting with Moldova, and we are talking about Poland, we are talking about Slovakia and Romania,” Halushchenko added, noting that how much will depend on their needs.
“For Poland, we have only one line that allows us to export 200 megawatts, but I think this month we will finish another line which will increase this to an additional 400 MW, so these figures could change,” he said.
Export revenue will depend on fluctuating electricity prices in Europe, where stunted hydro and nuclear output may hobble recovery efforts. In 2022, while Ukraine was still able to export energy, Ukrainian companies averaged 40 million to 70 million euros a month depending on prices, Halushchenko said.
“Even if it’s 20 (million euros) it’s still good money. We need financial resources now to restore generation and transmission lines,” he said.
Ukraine has the ability to export more than the 400 megawatt capacity limit imposed by the European Network of Transmission System Operators for Electricity, or ENTSO-E, and rising EU wind and solar output is reshaping cross-border flows. “We are in negotiations to increase this cap because today we can export even more, we have the necessary reserves in the system,” the minister said.
The current capacity limit is in line with what Ukraine was exporting in September 2022 before Ukraine diverted resources to meet domestic needs amid the Russian onslaught.
Ontario Hydro Crisis highlights soaring electricity rates, costly subsidies, nuclear refurbishments, and stalled renewables in Ontario. Policy missteps, weak planning, and rising natural gas emissions burden ratepayers while energy efficiency and storage remain underused.
Key Points
High power costs and subsidies from policy errors, nuclear refurbishments, stalled efficiency and renewables in Ontario.
✅ $5.6B yearly subsidy masks electricity rates and deficits
✅ Nuclear refurbishments embed rising costs for decades
✅ Efficiency, storage, and DERs stalled amid weak planning
By Mark Winfield
While the troubled Site C and Muskrat Falls hydroelectric dam projects in B.C. and Newfoundland and Labrador have drawn a great deal of national attention over the past few months, Ontario has quietly been having a hydro crisis of its own.
One of the central promises in the 2018 platform of the Ontario Progressive Conservative party was to “clean up the hydro mess,” and then-PC leader Doug Ford vowed to fire Hydro One's leadership as part of that effort. There certainly is a mess, with the costs of subsidies taken from general provincial revenues to artificially lower hydro rates nearing $7 billion annually. That is a level approaching the province’s total pre-COVID-19 annual deficit. After only two years, that will also exceed total expected cost overruns of the Site C and Muskrat Falls projects, currently estimated at $12 billion ($6 billion each).
There is no doubt that Doug Ford’s government inherited a significant mess around the province’s electricity system from the previous Liberal governments of former premiers Dalton McGuinty and Kathleen Wynne. But the Ford government has also demonstrated a remarkable capacity for undoing the things its predecessors had managed to get right while doubling down on their mistakes.
The Liberals did have some significant achievements. Most notably: coal-fired electricity generation, which constituted 25 per cent of the province’s electricity supply in the early 2000s, was phased out in 2014. The phaseout dramatically improved air quality in the province. There was also a significant growth in renewable energy production. From virtually zero in 2003, the province installed 4,500 MW of wind-powered generation, and 450 MW of solar photovoltaic by 2018, a total capacity more than double that of the Sir Adam Beck Generating Stations at Niagara Falls.
At the same time, public concerns over rising hydro rates flowing from a major reconstruction of the province’s electricity system from 2003 onwards became a central political issue in the province. But rather than reconsider the role of the key drivers of the continuing rate increases – namely the massively expensive and risky refurbishments of the Darlington and Bruce nuclear facilities, the Liberals adopted a financially ruinous Fair Hydro Plan. The central feature of the 2017 plan was a short-term 25 per cent reduction in hydro rates, financed by removing the provincial portion of the HST from hydro bills, and by extending the amortization period for capital projects within the system. The total cost of the plan in terms of lost revenues and financing costs has been estimated in excess of $40 billion over 29 years, with the burden largely falling on future ratepayers and taxpayers.
Decision-making around the electricity system became deeply politicized, and a secret cabinet forecast of soaring prices intensified public debate across Ontario. Legislation adopted by the Wynne government in 2016 eliminated the requirement for the development of system plans to be subject to any form of meaningful regulatory oversight or review. Instead, the system was guided through directives from the provincial cabinet. Major investments like the Darlington and Bruce refurbishments proceeded without meaningful, public, external reviews of their feasibility, costs or alternatives.
The Ford government proceeded to add more layers to these troubles. The province’s relatively comprehensive framework for energy efficiency was effectively dismantled in March, 2019, with little meaningful replacement. That was despite strong evidence that energy efficiency offered the most cost-effective strategy for reducing greenhouse gas emissions and electricity costs.
The Ford government basically retained the Fair Hydro Plan and promised further rate reductions, later tabling legislation to lower electricity rates as well. To its credit, the government did take steps to clarify real costs of the plan. Last year, these were revealed to amount to a de facto $5.6 billion-per-year subsidy coming from general revenues, and rising. That constituted the major portion of the province’s $7.4 billion pre-COVID-19 deficit. The financial hole was deepened further through November’s financial statement, with the addition of a further $1.3 billion subsidy to commercial and industrial consumers. The numbers can only get worse as the costs of the Darlington and Bruce refurbishments become embedded more fully into electricity rates.
The government also quietly dispensed with the last public vestige of an energy planning framework, relieving itself of the requirement to produce a Long-Term Energy Plan every three years. The next plan would normally have been due next month, in February.
Even the gains from the 2014 phaseout of coal-fired electricity are at risk. Major increases are projected in emissions of greenhouse gases, smog-causing nitrogen oxides and particulate matter from natural gas-fired power plants as the plants are run to cover electricity needs during the Bruce and Darlington refurbishments over the next decade. These developments could erode as much as 40 per cent of the improvements in air quality and greenhouse gas emission gained through the coal phaseout.
The province’s activities around renewable energy, energy storage and distributed energy resources are at a standstill, with exception of a few experimental “sandbox” projects, while other jurisdictions face profound electricity-sector change and adapt. Globally, these technologies are seen as the leading edge of energy-system development and decarbonization. Ontario seems to have chosen to make itself an energy innovation wasteland instead.
The overall result is a system with little or no space for innovation that is embedding ever-higher costs while trying to disguise those costs at enormous expense to the provincial treasury and still failing to provide effective relief to low-income electricity consumers.
The decline in electricity demand associated with the COVID-19 pandemic, along with the introduction of a temporary recovery rate for electricity, gives the province an opportunity to step back and consider its next steps with the electricity system. A phaseout of the Fair Hydro Plan electricity-rate reduction and its replacement with a more cost-effective strategy of targeted relief aimed at those most heavily burdened by rising hydro rates, particularly rural and low-income consumers, as reconnection efforts for nonpayment have underscored the hardship faced by many households, would be a good place to start.
Next, the province needs to conduct a comprehensive, public review of electricity options available to it, including additional renewables – the costs of which have fallen dramatically over the past decade – distributed energy resources, hydro imports from Quebec and energy efficiency before proceeding with further nuclear refurbishments.
In the longer term, a transparent, evidence-based process for electricity system planning needs to be established – one that is subject to substantive public and regulatory oversight and review. Finally, the province needs to establish a new organization to be called Energy Efficiency Ontario to revive its efforts around energy efficiency, developing a comprehensive energy-efficiency strategy for the province, covering electricity and natural gas use, and addressing the needs of marginalized communities.
Without these kinds of steps, the province seems destined to continue to lurch from contradictory decision after contradictory decision as the economic and environmental costs of the system’s existing trajectory continue to rise.
Mark Winfield is a professor of environmental studies at York University and co-chair of the university’s Sustainable Energy Initiative.
Alberta Last-Resort Power Rate Reform outlines consumer protection against market volatility, price spikes, and wholesale rate swings, promoting fixed-rate plans, price caps, transparency, and stable pricing mechanisms within Alberta's deregulated power market.
Key Points
Alberta Last-Resort Power Rate Reform seeks stable, transparent pricing and stronger consumer protections.
✅ Caps or hedges shield bills from wholesale price spikes
✅ Expand fixed-rate options and enrollment nudges
✅ Publish clear, real-time pricing and market risk alerts
Alberta’s electricity market is facing growing instability, with rising prices leaving many consumers struggling. The province's rate of last resort, a government-set price for people who haven’t chosen a fixed electricity plan, has become a significant concern. Due to volatile market conditions, this rate has surged, causing financial strain for households. Experts, like energy policy analyst Blake Shaffer, argue that the current market structure needs reform. They suggest creating more stability in pricing, ensuring better protection for consumers against unexpected price spikes, and addressing the flaws that lead to market volatility.
As electricity prices climb, many consumers are feeling the pressure. In Alberta, where energy deregulation is the norm in the electricity market, people without fixed-rate plans are automatically switched to the last-resort rate when their contracts expire. This price is based on fluctuating wholesale market rates, which can spike unexpectedly, leaving consumers vulnerable to sharp price increases. For those on tight budgets, such volatility makes it difficult to predict costs, leading to higher financial stress.
Blake Shaffer, a prominent energy policy expert, has been vocal about the need to address these issues. He has highlighted that while some consumers benefit from fixed-rate plans, with experts urging Albertans to lock in rates when possible, those who cannot afford them or who are unaware of their options often find themselves stuck with the unpredictable last-resort rate. This rate can be substantially higher than what a fixed-plan customer would pay, often due to rapid shifts in energy demand and supply imbalances.
Shaffer suggests that the province’s electricity market needs a restructuring to make it more consumer-friendly and less vulnerable to extreme price hikes. He argues that introducing more transparency in pricing and offering more stable options for consumers through new electricity rules could help. In addition, there could be better incentives for consumers to stay informed about their electricity plans, which would help reduce the number of people unintentionally placed on the last-resort rate.
One potential solution proposed by Shaffer and others is the creation of a more predictable and stable pricing mechanism, though a Calgary electricity retailer has urged the government to scrap an overhaul, where consumers could have access to reasonable rates that aren’t so closely tied to the volatility of the wholesale market. This could involve capping prices or offering government-backed insurance against large price fluctuations, making electricity more affordable for those who are most at risk.
The increasing reliance on market-driven prices has also raised concerns about Alberta’s energy policy changes and overall direction. As a province with a large reliance on oil and gas, Alberta’s energy sector is tightly connected to global energy trends. While this has its benefits, it also means that Alberta’s electricity prices are heavily influenced by factors outside the control of local consumers, such as geopolitical issues or extreme weather events. This makes it hard for residents to predict and plan their energy usage and costs.
For many Albertans, the current state of the electricity market feels precarious. As more people face unexpected price hikes, calls for a market overhaul continue to grow louder across Alberta. Shaffer and others believe that a new framework is necessary—one that balances the interests of consumers, the government, and energy companies, while ensuring that basic energy needs are met without overwhelming households with excessive costs.
In conclusion, Alberta’s last-resort electricity rate system is an increasing burden for many. While some may benefit from fixed-rate plans, others are left exposed to market volatility. Blake Shaffer advocates for reform to create a more stable, transparent, and affordable electricity market, one that could better protect consumers from the high risks associated with deregulated pricing. Addressing these challenges will be crucial in ensuring that energy remains accessible and affordable for all Alberta residents.
Nighttime Thermoelectric Generator converts radiative cooling into renewable energy, leveraging outer space cold; a Stanford-UCLA prototype complements solar, serving off-grid loads with low-power output during peak evening demand, using simple materials on a rooftop.
Key Points
A device converting nighttime radiative cooling into electricity, complementing solar for low-power evening needs.
✅ Uses thermocouples to convert temperature gradients to voltage.
✅ Exploits radiative cooling to outer space for night power.
✅ Complements solar; low-cost parts suit off-grid applications.
Two years ago, one freezing December night on a California rooftop, a tiny light shone weakly with a little help from the freezing night air. It wasn't a very bright glow. But it was enough to demonstrate the possibility of generating renewable power after the Sun goes down.
Working with Stanford University engineers Wei Li and Shanhui Fan, University of California Los Angeles materials scientist Aaswath Raman put together a device that produces a voltage by channelling the day's residual warmth into cooling air, effectively generating electricity from thin air with passive heat exchange.
"Our work highlights the many remaining opportunities for energy by taking advantage of the cold of outer space as a renewable energy resource," says Raman.
"We think this forms the basis of a complementary technology to solar. While the power output will always be substantially lower, it can operate at hours when solar cells cannot."
For all the merits of solar energy, it's just not a 24-7 source of power, although research into nighttime solar cells suggests new possibilities for after-dark generation. Sure, we can store it in a giant battery or use it to pump water up into a reservoir for later, but until we have more economical solutions, nighttime is going to be a quiet time for renewable solar power.
Most of us return home from work as the Sun is setting, and that's when energy demands spike to meet our needs for heating, cooking, entertaining, and lighting.
Unfortunately, we often turn to fossil fuels to make up the shortfall. For those living off the grid, it could require limiting options and going without a few luxuries.
Shanhui Fan understands the need for a night time renewable power source well. He's worked on a number of similar devices, including carbon nanotube generators that scavenge ambient energy, and a recent piece of technology that flipped photovoltaics on its head by squeezing electricity from the glow of heat radiating out of the planet's Sun-warmed surface.
While that clever item relied on the optical qualities of a warm object, this alternative device makes use of the good old thermoelectric effect, similar to thin-film waste-heat harvesting approaches now explored.
Using a material called a thermocouple, engineers can convert a change in temperature into a difference in voltage, effectively turning thermal energy into electricity with a measurable voltage. This demands something relatively toasty on one side and a place for that heat energy to escape to on the other.
The theory is the easy part – the real challenge is in arranging the right thermoelectric materials in such a way that they'll generate a voltage from our cooling surrounds that makes it worthwhile.
To keep costs down, the team used simple, off-the-shelf items that pretty much any of us could easily get our hands on.
They put together a cheap thermoelectric generator and linked it with a black aluminium disk to shed heat in the night air as it faced the sky. The generator was placed inside a polystyrene enclosure sealed with a window transparent to infrared light, and linked to a single tiny LED.
For six hours one evening, the box was left to cool on a roof-top in Stanford as the temperature fell just below freezing. As the heat flowed from the ground into the sky, the small generator produced just enough current to make the light flicker to life.
At its best, the device generated around 0.8 milliwatts of power, corresponding to 25 milliwatts of power per square metre.
That might just be enough to keep a hearing aid working. String several together and you might just be able to keep your cat amused with a simple laser pointer. So we're not talking massive amounts of power.
But as far as prototypes go, it's a fantastic starting point. The team suggests that with the right tweaks and the right conditions, 500 milliwatts per square metre isn't out of the question.
"Beyond lighting, we believe this could be a broadly enabling approach to power generation suitable for remote locations, and anywhere where power generation at night is needed," says Raman.
While we search for big, bright ideas to drive the revolution for renewables, it's important to make sure we don't let the smaller, simpler solutions like these slip away quietly into the night.
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.
