Perhaps the crowd for the open house at PPL Corp.'s Lake Wallenpaupack hydroelectric dam was an indication. There were old and young people alike, but few in between, suggesting most folks had found other things to do at this lakeside own on an overcast summer day.
That illustrates the public's attitude on electricity production. Consumers want it here on demand as cheaply as possible, but only those inquisitive few care about where it comes from or how it is transmitted. Consumers, attuned or indifferent, will get bigger electric bills in 2010 when prices in Pennsylvania jump perhaps 35 percent or more.
Electricity companies say it's an inevitable reaction to open-market prices that increased during the cap years. Alert customers might be confused.
Wait, they might ask, haven't bills already gone up? Haven't companies already received rate increases? Indeed, they have because only the generation rate, which accounts for about 40 percent of the total cost, was capped.
Utilities have been free to request and receive increases to transmission and distribution rates. This year alone, local provider PPL Electric Utilities has requested increases of about 10 percent. About half of that has already been granted by the state Public Utilities Commission.
Demand changes constantly, creating spikes that the industry must handle or risk blackouts. It's not cost effective for generating companies to always generate peak-period amounts, so the industry has created a two-tiered system to handle that demand. The first tier is large, efficient power plants that create vast amounts of power.
The plants are slow to turn on, but run almost continually, forming the backbone of the supply. The second tier includes small, often automated "peaking" plants that usually run on expensive fuel, but can be turned on almost instantly. They run when demand exceeds the large plants' output.
"The philosophy is entirely different," PPL spokesman George Lewis said. "Those plants are for the most part sitting in wait. If they get the call... they'd better be able to start." Electricity is sold by generating companies in an open market through a brokerage organization to utility companies. The brokerage solicits bids from the generating companies, and accepts the lowest ones first.
Generating companies, however, are all paid the highest accepted bid. So when expensive peaking units must be used, utilities pay a premium price for every megawatt. The rate caps, which began in 1996, have kept customers from feeling that effect. Also at issue is where plants are located. Because large plants often face opposition, they often are built where few people live.
Pennsylvania exported 70 billion kilowatt-hours in 2006, more than any other state, according to Doug Biden of the Electric Power Generation Association. All that power gets shipped through high-voltage lines, which themselves often receive opposition.
"I would say it's more difficult to build a transmission line than to build anything else just because of its length," state Consumer Advocate Sonny Popowsky said. They're also somewhat unreliable.
In August 2003, electricity-laden lines in Ohio sagged into a tree, sparking a blackout that crippled the Northeast. And PPL estimates energy lost to heat while traveling on the lines accounts for 9 percent of use. To control the price shocks that come with relying on one fuel, the industry plans to use a variety of fuels in the future. Politicians are pushing eco-friendly sources.
But such plants must go where the fuel is, requiring more transmission lines.
Furthermore, their energy-production-to-land-use efficiency is dwarfed by larger, more established plants. An example: The Susquehanna nuclear plant near Berwick can produce about six times more power per acre than the Bear Creek wind park. Renewable energy accounts for only 3 percent of total generation in the state, according to Biden.
Legislation might soon make renewable sources more appealing, though. Renewable energy quotas have been passed in some states, including Pennsylvania. More stringent carbon dioxide emissions caps would put heavy economic restrictions on coal plants. Many officials believe it comes down to personal responsibility.
"We have a society problem where we demand electricity" while complaining about its drawbacks, said Terry Williamson, a spokesman for the brokerage organization PJM Interconnection. "But you've gotta have the juice somewhere."
Eviation Collapse underscores electric aviation headwinds, from Alice aircraft battery limits to FAA/EASA certification hurdles, funding shortfalls, and leadership instability, reshaping sustainability roadmaps for regional airliners and future zero-emission flight.
Key Points
Eviation Collapse is the 2025 shutdown of Eviation Aircraft, revealing battery, certification, and funding hurdles.
✅ Battery energy density limits curtailed Alice's range
✅ Funding gaps and leadership churn undermined execution
The electric aviation industry was poised to revolutionize the skies through an aviation revolution with startups like Eviation Aircraft leading the charge to bring environmentally friendly, cost-efficient electric airplanes into commercial use. However, in a shocking turn of events, Eviation has faced an abrupt collapse, signaling challenges that may impact the future of electric flight.
Eviation’s Vision and Early Promise
Founded in 2015, Eviation was an ambitious electric airplane startup with the goal of changing the way the world thinks about aviation. The company’s flagship product, the Alice aircraft, was designed to be an all-electric regional airliner capable of carrying up to 9 passengers. With a focus on sustainability, reduced operating costs, and a quieter flight experience, Alice attracted attention as one of the most promising electric aircraft in development.
Eviation’s aircraft was aimed at replacing small, inefficient, and environmentally damaging regional aircraft, reducing emissions in the aviation industry. The startup’s vision was bold: to create an airplane that could offer all the benefits of electric power – lower operating costs, less noise, and a smaller environmental footprint. Their goal was not only to attract major airlines but also to pave the way for a more sustainable future in aviation.
The company’s early success was driven by substantial investments and partnerships. It garnered attention from aviation giants and venture capitalists alike, drawing support for its innovative technology. In fact, in 2019, Eviation secured a deal with the Israeli airline, El Al, for several aircraft, a deal that seemed to promise a bright future for the company.
Challenges in the Electric Aviation Industry
Despite its early successes and strong backing, Eviation faced considerable challenges that eventually contributed to its downfall. The electric aviation sector, as promising as it seemed, has always been riddled with hurdles – from battery technology to regulatory approvals, and compounded by Europe’s EV slump that dampened clean-transport sentiment, the path to producing commercially viable electric airplanes has proven more difficult than initially anticipated.
The first major issue Eviation encountered was the slow development of battery technology. While electric car companies like Tesla were able to scale their operations quickly during the electric vehicle boom due to advancements in battery efficiency, aviation technology faced a more significant obstacle. The energy density required for a plane to fly long distances with sufficient payload was far greater than what existing battery technology could offer. This limitation severely impacted the range of the Alice aircraft, preventing it from meeting the expectations set by its creators.
Another challenge was the lengthy regulatory approval process for electric aircraft. Aviation is one of the most regulated industries in the world, and getting a new aircraft certified for flight takes time and rigorous testing. Although Eviation’s Alice was touted as an innovative leap in aviation technology, the company struggled to navigate the complex process of meeting the safety and operational standards required by aviation authorities, such as the FAA and EASA.
Financial Difficulties and Leadership Changes
As challenges mounted, Eviation’s financial situation became increasingly precarious. The company struggled to secure additional funding to continue its development and scale operations. Investors, once eager to back the promising startup, grew wary as timelines stretched and costs climbed, amid a U.S. EV market share dip in early 2024, tempering enthusiasm. With the electric aviation market still in its early stages, Eviation faced stiff competition from more established players, including large aircraft manufacturers like Boeing and Airbus, who also began to invest heavily in electric and hybrid-electric aircraft technologies.
Leadership instability also played a role in Eviation’s collapse. The company went through several executive changes over a short period, and management’s inability to solidify a clear vision for the future raised concerns among stakeholders. The lack of consistent leadership hindered the company’s ability to make decisions quickly and efficiently, further exacerbating its financial challenges.
The Sudden Collapse
In 2025, Eviation made the difficult decision to shut down its operations. The company announced the closure after failing to secure enough funding to continue its development and meet its ambitious production goals. The sudden collapse of Eviation sent shockwaves through the electric aviation sector, where many had placed their hopes on the startup’s innovative approach to electric flight.
The failure of Eviation has left many questioning the future of electric aviation. While the industry is still in its infancy, Eviation’s downfall serves as a cautionary tale about the challenges of bringing cutting-edge technology to the skies. The ambitious vision of a sustainable, electric future in aviation may still be achievable, but the path to success will require overcoming significant technological, regulatory, and financial obstacles.
What’s Next for Electric Aviation?
Despite Eviation’s collapse, the electric aviation sector is far from dead. Other companies, such as Joby Aviation, Vertical Aerospace, and Ampaire, are continuing to develop electric and hybrid-electric aircraft, building on milestones like Canada’s first commercial electric flight that signal ongoing demand for green alternatives to traditional aviation.
Moreover, major aircraft manufacturers are doubling down on their own electric aircraft projects. Boeing, for example, has launched several initiatives aimed at reducing carbon emissions in aviation, while Harbour Air’s point-to-point e-seaplane flight showcases near-term regional progress, and Airbus is testing a hybrid-electric airliner prototype. The collapse of Eviation may slow down progress, but it is unlikely to derail the broader movement toward electric flight entirely.
The lessons learned from Eviation’s failure will undoubtedly inform the future of the electric aviation sector. Innovation, perseverance, and a steady stream of investment will be critical for the success of future electric aircraft startups, as exemplified by Harbour Air’s research-driven electric aircraft efforts that highlight the value of sustained R&D. While the dream of electric planes may have suffered a setback, the long-term vision of cleaner, more sustainable aviation is still alive.
Canada Wind Energy Costs are plunging as renewable energy auctions, CfD contracts, and efficient turbines drive prices to 2-4 cents/kWh across Alberta and Saskatchewan, outcompeting grid power via competitive bidding and improved capacity factors.
Key Points
Averaging 2-4 cents/kWh via auctions, CfD support, and bigger turbines, wind is now cost-competitive across Canada.
✅ Alberta CfD bids as low as 3.9 cents/kWh.
✅ Turbine outputs rose from 1 MW to 3.3 MW per tower.
✅ Competitive auctions cut costs ~70% over nine years.
It's taken a decade of technological improvement and a new competitive bidding process for electrical generation contracts, but wind may have finally come into its own as one of the cheapest ways to create power.
Ten years ago, Ontario was developing new wind power projects at a cost of 28 cents per kilowatt hour (kWh), the kind of above-market rate that the U.K., Portugal and other countries were offering to try to kick-start development of renewables.
Now some wind companies say they've brought generation costs down to between 2 and 4 cents — something that appeals to provinces that are looking to significantly increase their renewable energy deployment plans.
The cost of electricity varies across Canada, by province and time of day, from an average of 6.5 cents per kWh in Quebec to as much as 15 cents in Halifax.
Capital Power, an Edmonton-based company, recently won a contract for the Whitla 298.8-megawatt (MW) wind project near Medicine Hat, Alta., with a bid of 3.9 cents per kWh, at a time when three new solar facilities in Alberta have been contracted at lower cost than natural gas, underscoring the trend. That price covers capital costs, transmission and connection to the grid, as well as the cost of building the project.
Jerry Bellikka, director of government relations, said Capital Power has been building wind projects for a decade, in the U.S., Alberta, B.C. and other provinces. In that time the price of wind generation equipment has been declining continually, while the efficiency of wind turbines increases.
Increased efficiency
"It used to be one tower was 1 MW; now each turbine generates 3.3 MW. There's more electricity generated per tower than several years ago," he said.
One wild card for Whitla may be steel prices — because of the U.S. and Canada slapping tariffs on one other's steel and aluminum products. Whitla's towers are set to come from Colorado, and many of the smaller components from China.
Canada introduces new surtaxes to curb flood of steel imports
"We haven't yet taken delivery of the steel. It remains to be seen if we are affected by the tariffs." Belikka said.
Another company had owned the site and had several years of meteorological data, including wind speeds at various heights on the site, which is in a part of southern Alberta known for its strong winds.
But the choice of site was also dependent on the municipality, with rural Forty Mile County eager for the development, Belikka said.
Alberta aims for 30% electricity from wind by 2030
Alberta wants 30 per cent of its electricity to come from renewable sources by 2030 and, as an energy powerhouse, is encouraging that with a guaranteed pricing mechanism in what is otherwise a market-bidding process.
While the cost of generating energy for the Alberta Electric System Operator (AESO) fluctuates hourly and can be a lot higher when there is high demand, the winners of the renewable energy contracts are guaranteed their fixed-bid price.
The average pool price of electricity last year in Alberta was 5 cents per kWh; in boom times it rose to closer to 8 cents. But if the price rises that high after the wind farm is operating, the renewable generator won't get it, instead rebating anything over 3.9 cents back to the government.
On the other hand, if the average or pool price is a low 2 cents kWh, the province will top up their return to 3.9 cents.
This contract-for-differences (CfD) payment mechanism has been tested in renewable contracts in the U.K. and other jurisdictions, including some U.S. states, according to AESO.
Competitive bidding in Saskatchewan
In Saskatchewan, the plan is to double its capacity of renewable electricity, to 50 per cent of generation capacity, by 2030, and it uses an open bidding system between the private sector generator and publicly owned SaskPower.
In bidding last year on a renewable contract, 15 renewable power developers submitted bids, with an average price of 4.2 cents per kWh.
One low bidder was Potentia with a proposal for a 200 MW project, which should provide electricity for 90,000 homes in the province, at less than 3 cents kWh, according to Robert Hornung of the Canadian Wind Energy Association.
"The cost of wind energy has fallen 70 per cent in the last nine years," he says. "In the last decade, more wind energy has been built than any other form of electricity."
Ontario remains the leading user of wind with 4,902 MW of wind generation as of December 2017, most of that capacity built under a system that offered an above-market price for renewable power, put in place by the previous Liberal government.
In June of last year, the new Conservative government of Doug Ford halted more than 700 renewable-energy projects, one of them a wind farm that is sitting half-built, even as plans to reintroduce renewable projects continue to advance.
The feed-in tariff system that offered a higher rate to early builders of renewable generation ended in 2016, but early contracts with guaranteed prices could last up to 20 years.
Hornung says Ontario now has an excess of generating capacity, as it went on building when the 2008-9 bust cut market consumption dramatically.
But he insists wind can compete in the open market, offering low prices for generation when Ontario needs new capacity.
"I expect there will be competitive processes put in place. I'm quite confident wind projects will continue to go ahead. We're well positioned to do that."
Dubai Green Hydrogen advances electrolysis at the Mohammed Bin Rashid Al Maktoum Solar Park, with DEWA and Siemens enabling clean energy storage, re-electrification, and fuel-cell mobility for Expo 2020 Dubai and public transport.
Key Points
Dubai Green Hydrogen is a DEWA-Siemens project making solar hydrogen for storage, mobility, and reelectrification.
✅ Electrolysis at Mohammed Bin Rashid Al Maktoum Solar Park
✅ Partners: DEWA and Siemens; public-private demonstration plant
✅ Hydrogen for buses, re-electrification, and energy storage
Something you hear frequently if you are a clean tech aficionado is that excess solar and wind power can be used to split water into oxygen and hydrogen. The Dubai Supreme Council of Energy, the 2020 Dubai Higher Committee and the Dubai Electricity and Water Authority broke ground in early February on a solar power hydrogen electrolysis facility located in the Mohammed Bin Rashid Al Maktoum Solar Park, and related initiatives like the Solar Decathlon Middle East underscore Dubai's clean energy focus. Sheikh Ahmed bin Saeed Al Maktoum, chairman of the Dubai Supreme Council of Energy and chairman of the Expo 2020 Dubai Higher Committee, participated in the groundbreaking ceremony, according to a report by Khaleej Times.
Saeed Mohammed Al Tayer, CEO of DEWA, said at the groundbreaking ceremony the project is important to understanding the limits of green hydrogen technology and how it can contribute to the UAE’s vision of clean energy, and aligns with DEWA's latest renewable initiatives now progressing in the emirate. “This pioneering project is a role model for strategic partnerships between the public and private sectors. It will contribute to developing the green economy concept in the UAE and explore the potential of green hydrogen technology. The hydrogen produced at the facility will be stored and deployed for re-electrification, transportation and other uses.”
Siemens is providing much of the technology that will be used at the demonstration facility, while DEWA expands its China outreach to woo renewable energy firms that can contribute to the ecosystem. Joe Kaeser, president and CEO of Siemens, said the UAE was the perfect location for Siemens to test the technology, building on advances in offshore green hydrogen the company is pursuing. One of the primary uses of the hydrogen produced will be to power Dubai’s public transportation system.
“We are aware of the stress that is placed on vehicles in this region due to the high levels of heat; with hydrogen cells, you are not putting as much strain on the vehicle and that improves its longevity,” Kaeser said. “However, this is only the first step and we are eager to explore more ways in which we can adapt the technology to other sectors. The interest from various companies and partners has been immense and we are eager to work with all interested parties.”
“Dewa, Expo 2020 Dubai and Siemens are working together to help realize His Highness Sheikh Mohammed bin Rashid Al Maktoum, Vice-President and Prime Minister of the UAE and Ruler of Dubai’s, vision to identify new energy resources and provide sustainable power as part of a balanced approach that prioritizes the environment. Our aim is to make Dubai a model of energy efficiency and safety,” said Sheikh Ahmed.
Expo 2020 Dubai intends to use the hydrogen generated at the facility to transport visitors to the Expo 2020 Dubai and the Mohammed bin Rashid Al Maktoum Solar Park, reflecting regional momentum such as Saudi Arabia's clean energy plans over the next decade, in hydrogen fuel cell powered vehicles. Live data of the green hydrogen electrolysis will be displayed at Expo 2020 Dubai to help inform broader efforts like hydrogen hubs in the United States.
CO2 Removal Technologies address climate change via negative emissions, including carbon capture, reforestation, soil carbon, biochar, BECCS, DAC, and mineralization, helping meet Paris Agreement targets while managing costs, land use, and infrastructure demands.
Key Points
Methods to extract or sequester atmospheric CO2, combining natural and engineered approaches to limit warming.
✅ Includes reforestation, soil carbon, biochar, BECCS, DAC, mineralization
✅ Balances climate goals with costs, land, energy, and infrastructure
✅ Key to Paris Agreement targets under 1.5-2.0 °C warming
The world is, on average, 1.1 degrees Celsius warmer today than it was in 1850. If this trend continues, our planet will be 2 – 3 degrees hotter by the end of this century, according to the Intergovernmental Panel on Climate Change (IPCC).
The main reason for this temperature rise is higher levels of atmospheric carbon dioxide, which cause the atmosphere to trap heat radiating from the Earth into space. Since 1850, the proportion of CO2 in the air has increased, with record greenhouse gas concentrations documented, from 0.029% to 0.041% (288 ppm to 414 ppm).
This is directly related to the burning of coal, oil and gas, which were created from forests, plankton and plants over millions of years. Back then, they stored CO2 and kept it out of the atmosphere, but as fossil fuels are burned, that CO2 is released. Other contributing factors include industrialized agriculture and slash-and-burn land clearing techniques, and emissions from SF6 in electrical equipment are also concerning today.
Over the past 50 years, more than 1200 billion tons of CO2 have been emitted into the planet's atmosphere — 36.6 billion tons in 2018 alone, though global emissions flatlined in 2019 before rising again. As a result, the global average temperature has risen by 0.8 degrees in just half a century.
Atmospheric CO2 should remain at a minimum In 2015, the world came together to sign the Paris Climate Agreement which set the goal of limiting global temperature rise to well below 2 degrees — 1.5 degrees, if possible.
The agreement limits the amount of CO2 that can be released into the atmosphere, providing a benchmark for the global energy transition now underway. According to the IPCC, if a maximum of around 300 billion tons were emitted, there would be a 50% chance of limiting global temperature rise to 1.5 degrees. If CO2 emissions remain the same, however, the CO2 'budget' would be used up in just seven years.
According to the IPCC's report on the 1.5 degree target, negative emissions are also necessary to achieve the climate targets.
Using reforestation to remove CO2 One planned measure to stop too much CO2 from being released into the atmosphere is reforestation. According to studies, 3.6 billion tons of CO2 — around 10% of current CO2 emissions — could be saved every year during the growth phase. However, a study by researchers at the Swiss Federal Institute of Technology, ETH Zurich, stresses that achieving this would require the use of land areas equivalent in size to the entire US.
Young trees at a reforestation project in Africa (picture-alliance/OKAPIA KG, Germany) Reforestation has potential to tackle the climate crisis by capturing CO2. But it would require a large amount of space
More humus in the soil Humus in the soil stores a lot of carbon. But this is being released through the industrialization of agriculture. The amount of humus in the soil can be increased by using catch crops and plants with deep roots as well as by working harvest remnants back into the ground and avoiding deep plowing. According to a study by the German Institute for International and Security Affairs (SWP) on using targeted CO2 extraction as a part of EU climate policy, between two and five billion tons of CO2 could be saved with a global build-up of humus reserves.
Biochar shows promise Some scientists see biochar as a promising technology for keeping CO2 out of the atmosphere. Biochar is created when organic material is heated and pressurized in a zero or very low-oxygen environment. In powdered form, the biochar is then spread on arable land where it acts as a fertilizer. This also increases the amount of carbon content in the soil. According to the same study from the SWP, global application of this technology could save between 0.5 and two billion tons of CO2 every year.
Storing CO2 in the ground Storing CO2 deep in the Earth is already well-known and practiced on Norway's oil fields, for example. However, the process is still controversial, as storing CO2 underground can lead to earthquakes and leakage in the long-term. A different method is currently being practiced in Iceland, in which CO2 is sequestered into porous basalt rock to be mineralized into stone. Both methods still require more research, however, with new DOE funding supporting carbon capture, utilization, and storage.
Capturing CO2 to be held underground is done by using chemical processes which effectively extract the gas from the ambient air, and some researchers are exploring CO2-to-electricity concepts for utilization. This method is known as direct air capture (DAC) and is already practiced in other parts of Europe. As there is no limit to the amount of CO2 that can be captured, it is considered to have great potential. However, the main disadvantage is the cost — currently around €550 ($650) per ton. Some scientists believe that mass production of DAC systems could bring prices down to €50 per ton by 2050. It is already considered a key technology for future climate protection.
The inside of a carbon capture facility in the Netherlands (RWE AG) Carbon capture facilities are still very expensive and take up a huge amount of space
Another way of extracting CO2 from the air is via biomass. Plants grow and are burned in a power plant to produce electricity. CO2 is then extracted from the exhaust gas of the power plant and stored deep in the Earth, with new U.S. power plant rules poised to test such carbon capture approaches.
The big problem with this technology, known as bio-energy carbon capture and storage (BECCS) is the huge amount of space required. According to Felix Creutzig from the Mercator Institute on Global Commons and Climate Change (MCC) in Berlin, it will therefore only play "a minor role" in CO2 removal technologies.
CO2 bound by rock minerals In this process, carbonate and silicate rocks are mined, ground and scattered on agricultural land or on the surface water of the ocean, where they collect CO2 over a period of years. According to researchers, by the middle of this century it would be possible to capture two to four billion tons of CO2 every year using this technique. The main challenges are primarily the quantities of stone required, and building the necessary infrastructure. Concrete plans have not yet been researched.
Not an option: Fertilizing the sea with iron The idea is use iron to fertilize the ocean, thereby increasing its nuturient content, which would allow plankton to grow stronger and capture more CO2. However, both the process and possible side effects are very controversial. "This is rarely treated as a serious option in research," concludes SWP study authors Oliver Geden and Felix Schenuit.
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.
Yukon SMR Feasibility Study examines small modular reactors as low-emissions nuclear power for Yukon's grid and remote communities, comparing costs, safety, waste, and reliability with diesel generation, renewables, and energy efficiency.
Key Points
An official assessment of small modular reactors as low-emission power options for Yukon's grid and remote sites.
✅ Compares SMR costs vs diesel, hydro, wind, and solar
✅ Considers remote community loads and grid integration
The Yukon government is looking for ways to reduce the territory's emissions, and wondering if nuclear power is one way to go.
The territory is undertaking a feasibility study, and, as some developers note, combining multiple energy sources can make better projects, to determine whether there's a future for SMRs — small modular reactors — as a low-emissions alternative to things such as diesel power.
The idea, said John Streicker, Yukon's minister of energy, mines and resources, is to bring the SMRs into the Yukon to generate electricity.
"Even the micro ones, you could consider in our remote communities or wherever you've got a point load of energy demand," Streicker said. "Especially electricity demand."
For remote coastal communities elsewhere in Canada, tidal energy is being explored as a low-emissions option as well.
SMRs are nuclear reactors that use fission to produce energy, similar to existing large reactors, but with a smaller power capacity. The International Atomic Energy Agency (IAEA) defines reactors as "small" if their output is under 300 MW. A traditional nuclear power plant produces about three times as much power or more.
They're "modular" because they're designed to be factory-assembled, and then installed where needed.
Several provinces have already signed an agreement supporting the development of SMRs, and in Alberta's energy mix that conversation spans both green and fossil power, and Canada's first grid-scale SMRs could be in place in Ontario by 2028 and Saskatchewan by 2032.
A year ago, the government of Yukon endorsed Canada's SMR action plan, at a time when analysts argue that zero-emission electricity by 2035 is practical and profitable, agreeing to "monitor the progress of SMR technologies throughout Canada with the goal of identifying potential for applicability in our northern jurisdiction."
The territory is now following through by hiring someone to look at whether SMRs could make sense as a cleaner-energy alternative in Yukon.
The territorial government has set a goal of reducing emissions by 45 per cent by 2030, excluding mining emissions, even as some analyses argue that zero-emissions electricity by 2035 is possible, and "future emissions actions for post-2030 have not yet been identified," reads the government's request for proposals to do the SMR study.
Streicker acknowledges the potential for nuclear power in Yukon is a bit of "long shot" — but says it's one that can't be ignored.
"We need to look at all possible solutions," he said, as countries such as New Zealand's electricity sector debate their future pathways.
"I don't want to give the sense like we're putting all of our emphasis and energy towards nuclear power. We're not."
According to Streicker, it's nothing more than a study at this point.
Don't bother, researcher says Still, M.V. Ramana, a professor at the School of Public Policy and Global Affairs at the University of British Columbia, said it's a study that's likely a waste of time and money. He says there's been plenty of research already, and to him, SMRs are just not a realistic option for Yukon or anywhere in Canada.
"I would say that, you know, that study can be done in two weeks by a graduate student, essentially, all right? They just have to go look at the literature on SMRs and look at the critical literature on this," Ramana said.
Ramana co-authored a research paper last year, looking at the potential for SMRs in remote communities or mine sites. The conclusion was that SMRs will be too expensive and there won't be enough demand to justify investing in them.
He said nuclear reactors are expensive, which is why their construction has "dried up" in much of the world.
"They generate electricity at very high prices," he said.
'They just have to go look at the literature,' said M.V. Ramana, a professor at the School of Public Policy and Global Affairs at the University of British Columbia. (Paul Joseph) "[For] smaller reactors, the overall costs go down. But the amount of electricity that they will generate goes down even further."
The environmental case is also shaky, according to a statement signed last year by dozens of Canadian environmental and community groups, including the Sierra Club, Greenpeace, the Council of Canadians and the Canadian Environmental Law Associaton (CELA). The statement calls SMRs a "dirty, dangerous distraction" from tackling climate change and criticized the federal government for investing in the technology.
"We have to remember that the majority of the rhetoric we hear is from nuclear advocates. And so they are promoting what I would call, and other legal scholars and academics have called, a nuclear fantasy," said Kerrie Blaise of CELA.
Blaise describes the nuclear industry as facing an unknown future, with some of North America's larger reactors set to be decommissioned in the coming years. SMRs are therefore touted as the future.
"They're looking for a solution. And so that I would say climate change presents that timely solution for them."
Blaise argues the same safety and environmental questions exist for SMRs as for any nuclear reactors — such as how to produce and transport fuel safely, what to do with waste, and how to decommission them — and those can't be glossed over in a single-minded pursuit of lower carbon emissions.
Main focus is still renewables, minister says Yukon's energy minister agrees, and he's eager to emphasize that the territory is not committed to anything right now beyond a study.
"Every government has a responsibility to do diligence around this," Streicker said.
A solar farm in Old Crow, Yukon. The territory's energy minister says Yukon is still primarily focussed on renewables, and energy efficiency. (Caleb Charlie) He also dismisses the idea that studying nuclear power is any sort of distraction from his government's response to climate change right now. Yukon's main focus is still renewable energy such as solar and wind power, though Canada's solar progress is often criticized as lagging, increasing efficiency, and connecting Yukon's grid to the hydro project in Atlin, B.C., he said.
Streicker has been open to nuclear energy in the past. As a federal Green Party candidate in 2008, Streicker broke with the party line to suggest that nuclear could be a viable energy alternative.
He acknowledges that nuclear power is always a hot-button issue, and Yukoners will have strong feelings about it. A lot will depend on how any future regulatory process works, he says.
In taking action on climate, this Arctic community wants to be a beacon to the world Cameco signs agreement with nuclear reactor company "There's some people that think it's the 'Hail Mary,' and some people that think it's evil incarnate," he said.
"Buried deep within Our Clean Future [Yukon's climate change strategy], there's a line in there that says we should keep an eye on other technologies, for example, nuclear. That's what this [study] is — it's to keep an eye on it."
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