Siemens Limited, the flagship Indian company of Siemens AG, has secured two power transmission contracts worth $22.67 million from Power Grid Corporation of India Limited (PGCIL), for the construction and upgrade of two substations associated with transmission of power from the 4,000-megwatt (MW) ultra-mega power projects (UMPPs) being developed in Sasan in Madhya Pradesh and Mundra in Gujarat.
The first contract pertains to the construction of a new 400/220-kilovolt (kV) substation in Bachau, Gujarat, as part of the associated transmission system for the UMPP being set up in Mundra by Tata Power Company Limited. Under the contract, Siemens will also upgrade two existing substations operated by Gujarat Energy Transmission Corporation Limited in Ranchodpura and Limbdi in the state. The project will enable the transmission of bulk power generated by the UMPP to the western region.
Under the second contract, Siemens will undertake the extensions of two 400-kV substations in Maithon in Jharkhand and Biharshariff in Bihar to enable transmission of bulk power generated by the Sasan UMPP to the northern region. These projects will be executed as part of the common scheme for network in the western region, and the common scheme for network and 765-kV pooling stations in the northern region.
Both contracts are to be executed within the next 12 to 24 months on a turnkey basis. Siemens will be responsible for the design, engineering, supply and commissioning of the substations and will also supply high-end technology products such as disconnectors, instrument transformers, circuit breakers, and equipment for control and protection. The components and equipment will be manufactured at the firm's factories in Aurangabad and Kalwa in Maharashtra, and Hyderabad in Andhra Pradesh.
The two projects are part of PGCIL's plans to augment the capacity of the national grid to transmit more than 37,000 MW of power by the end of the ongoing Eleventh Five-Year Plan period (2007-12). PGCIL aims to achieve this target by strengthening the regional grids and developing more inter-regional transmission links.
This undertaking is estimated to entail an investment of $11.44 billion.
In April this year, the firm announced that it has earmarked funds of $2.5 billion for its capital expenditure program for the current fiscal year, 2009-10, and of $3.12 billion for the next fiscal year, 2010-11. As of December 31, 2008, the firm had enhanced the capacity of the national grid to transmit 18,700 MW of power.
PGCIL is currently implementing 45 projects in order to increase its transmission network by 30,536 circuit kilometers and transformation capacity by 29,420 megavolt-amperes (MVA). The firm plans to implement an interconnector project, estimated at $2.31 billion, to evacuate and transmit surplus power from the northeastern region to the power-deprived northern and western regions of the country. Implementation of this project is expected to commence by the end of this month.
Other projects in the pipeline include a $1.04 billion transmission system associated with the Krishnapatnam UMPP in Andhra Pradesh and another $1.04 billion transmission project for independent power producers in the state.
About 45% of the total power generated in the country is currently routed through PGCIL's transmission network. During the Tenth Five-Year Plan (2002-07), the firm was able to achieve its physical target for the period with lower capital outlay than was planned. Against an approved outlay of $4.44 billion, PGCIL invested $3.93 billion and added about 19,170 circuit kilometers of extra-high-voltage alternating current (EHVAC) transmission lines and 36 extra-high-voltage substations with a total transformation capacity of 25,130 MVA.
At the end of the period, the firm had a transmission network of 59,461 circuit kilometers and 104 substations with a total transformation capacity of 59,417 MVA. Industry analysts are optimistic about PGCIL being able to repeat its performance and achieve company targets for the current plan period. The firm presently operates about 71,500 circuit kilometers of transmission network and 120 EHVAC and high-voltage direct current substations with an aggregate transformation capacity of 79,500 MVA.
EV Grid Capacity Management shows how smart charging, load balancing, and off-peak pricing align with utility demand response, DC fast charging networks, and renewable integration to keep national electricity infrastructure reliable as EV adoption scales
Key Points
EV Grid Capacity Management schedules charging and balances load to keep EV demand within utility capacity.
✅ Off-peak pricing and time-of-use tariffs shift charging demand.
✅ Smart chargers enable demand response and local load balancing.
✅ Gradual EV adoption allows utilities to plan upgrades efficiently.
One of the most frequent concerns you will see from electric vehicle haters is that the electricity grid can’t possibly cope with all cars becoming EVs, or that EVs will crash the grid entirely. However, they haven’t done the math properly. The grids in most developed nations will be just fine, so long as the demand is properly management. Here’s how.
The biggest mistake the social media keyboard warriors make is the very strange assumption that all cars could be charging at once. In the UK, there are currently 32,697,408 cars according to the UK Department of Transport. The UK national grid had a capacity of 75.8GW in 2020. If all the cars in the UK were EVs and charging at the same time at 7kW (the typical home charger rate), they would need 229GW – three times the UK grid capacity. If they were all charging at 50kW (a common public DC charger rate), they would need 1.6TW – 21.5 times the UK grid capacity. That sounds unworkable, and this is usually the kind of thinking behind those who claim the UK grid can't cope with EVs.
What they don’t seem to realize is that the chances of every single car charging all at once are infinitesimally low. Their arguments seem to assume that nobody ever drives their car, and just charges it all the time. If you look at averages, the absurdity of this position becomes particularly clear. The distance each UK car travels per year has been slowly dropping, and was 7,400 miles on average in 2019, again according to the UK Department of Transport. An EV will do somewhere between 2.5 and 4.5 miles per kWh on average, so let’s go in the middle and say 3.5 miles. In other words, each car will consume an average of 2,114kWh per year. Multiply that by the number of cars, and you get 69.1TWh. But the UK national grid produced 323TWh of power in 2019, so that is only 21.4% of the energy it produced for the year. Before you argue that’s still a problem, the UK grid produced 402TWh in 2005, which is more than the 2019 figure plus charging all the EVs in the UK put together. The capacity is there, and energy storage can help manage EV-driven peaks as well.
Let’s do the same calculation for the USA, where an EV boom is about to begin and planning matters. In 2020, there were 286.9 million cars registered in America. In 2020, while the US grid had 1,117.5TW of utility electricity capacity and 27.7GW of solar, according to the US Energy Information Administration. If all the cars were EVs charging at 7kW, they would need 2,008.3TW – nearly twice the grid capacity. If they charged at 50kW, they would need 14,345TW – 12.8 times the capacity.
However, in 2020, the US grid generated 4,007TWh of electricity. Americans drive further on average than Brits – 13,500 miles per year, according to the US Department of Transport’s Federal Highway Administration. That means an American car, if it were an EV, would need 3,857kWh per year, assuming the average efficiency figures above. If all US cars were EVs, they would need a total of 1,106.6TWh, which is 27.6% of what the American grid produced in 2020. US electricity consumption hasn’t shrunk in the same way since 2005 as it has in the UK, but it is clearly not unfeasible for all American cars to be EVs. The US grid could cope too, even as state power grids face challenges during the transition.
After all, the transition to electric isn’t going to happen overnight. The sales of EVs are growing fast, with for example more plug-ins sold in the UK in 2021 so far than the whole of the previous decade (2010-19) put together. Battery-electric vehicles are closing in on 10% of the market in the UK, and they were already 77.5% of new cars sold in Norway in September 2021. But that is new cars, leaving the vast majority of cars on the road fossil fuel powered. A gradual introduction is essential, too, because an overnight switchover would require a massive ramp up in charge point installation, particularly devices for people who don’t have the luxury of home charging. This will require considerable investment, but could be served by lots of chargers on street lamps, which allegedly only cost £1,000 ($1,300) each to install, usually with no need for extra wiring.
This would be a perfectly viable way to provide charging for most people. For example, as I write this article, my own EV is attached to a lamppost down the street from my house. It is receiving 5.5kW costing 24p (32 cents) per kWh through SimpleSocket, a service run by Ubitricity (now owned by Shell) and installed by my local London council, Barnet. I plugged in at 11am and by 7.30pm, my car (which was on about 28% when I started) will have around 275 miles of range – enough for a couple more weeks. It will have cost me around £12 ($16) – way less than a tank of fossil fuel. It was a super-easy process involving the scanning of a QR code and entering of a credit card, very similar to many parking systems nowadays. If most lampposts had one of these charging plugs, not having off-street parking would be no problem at all for owning an EV.
With most EVs having a range of at least 200 miles these days, and the average mileage per day being 20 miles in the UK (the 7,400-mile annual figure divided by 365 days) or 37 miles in the USA, EVs won’t need charging more than once a week or even every week or two. On average, therefore, the grids in most developed nations will be fine. The important consideration is to balance the load, because if too many EVs are charging at once, there could be a problem, and some regions like California are looking to EVs for grid stability as part of the solution. This will be a matter of incentivizing charging during off-peak times such as at night, or making peak charging more expensive. It might also be necessary to have the option to reduce charging power rates locally, while providing the ability to prioritize where necessary – such as emergency services workers. But the problem is one of logistics, not impossibility.
There will be grids around the world that are not in such a good place for an EV revolution, at least not yet, and some critics argue that policies like Canada's 2035 EV mandate are unrealistic. But to argue that widespread EV adoption will be an insurmountable catastrophe for electricity supply in developed nations is just plain wrong. So long as the supply is managed correctly to make use of spare capacity when it’s available as much as possible, the grids will cope just fine.
Texas PUC Appointments signal post-storm reform as Gov. Greg Abbott taps Peter Lake and advances Will McAdams for Senate confirmation, affecting ERCOT oversight, grid reliability, wholesale power pricing, and securitization for co-ops.
Key Points
Texas PUC appointments add Peter Lake and Will McAdams to steer ERCOT, grid reliability, and market policy.
✅ Peter Lake nominated chair to replace Arthur D'Andrea.
✅ Will McAdams advances toward Senate confirmation.
✅ Focus on ERCOT oversight, price cap debate, grid resilience.
A new set of Texas electricity regulators began to take shape Monday, as Gov. Greg Abbott nominated a finance expert to be the next chairman of the Public Utility Commission while his earlier choice of a PUC member moved toward Senate confirmation.
The Republican governor put forward Peter Lake of Austin, who has spent more than five years as an Abbott appointee to the Texas Water Development Board, as his second commission pick in as many weeks.
“I am confident he will bring a fresh perspective and trustworthy leadership to the PUC,” Abbott said of Lake, who once worked as a trader of futures and derivatives for a firm belonging to the Chicago Mercantile Exchange and more recently has eagerly promoted bonds for the State Water Implementation Fund for Texas.
“Peter’s expertise in the Texas energy industry and business management will make him an asset to the agency,” Abbott, who has touted grid readiness in recent months, said in a written statement. “I urge the Senate to swiftly confirm Peter’s appointment.”
On Monday, the Senate appeared to be moving quickly to confirm Abbott’s April 1 selection for the PUC, Will McAdams, president of Associated Builders and Contractors of Texas and a former legislative aide who helped write policy for regulated industries such as electricity.
McAdams was among the 129 nominees that the Senate Nominations Committee voted out, 8-0. His nomination heads now to the Senate floor.
All three of Abbott’s handpicked PUC commissioners who were in place before and during February’s calamitous winter storm have since quit or said they’re resigning, even as Sierra Club criticism of Abbott's demands intensified in the aftermath.
February’s polar vortex left in its wake physical and financial wreckage after a nonprofit grid operator answering to the PUC, amid calls for market reforms to avoid blackouts, shut off electricity to more than 4 million Texans, causing the deaths of at least 125 people, 13 of them in the Dallas-Fort Worth area.
Gov. Greg Abbott on Thursday named Will McAdams to the embattled Public Utility Commission of Texas. McAdams is a construction industry lobbyist with strong ties to the GOP-controlled Legislature. In Feb. 17 file photo, winter storm's snowfall andn large electrical transmission lines in South Arlington are pictured.
In a 45-minute confirmation hearing, McAdams, as lawmakers discussed ways to improve electricity reliability statewide, drew praise – and few tough questions.
McAdams, who previously worked for three GOP senators, testified that had he been on the commission in February, he would not have kept in place a controversial, $9,000-per-megawatt hour price cap on wholesale power for about 32 hours on Feb. 18-19.
“I don’t see myself making that decision,” he said.
McAdams, though, hedged slightly, saying he’s not privy to all information that the Electric Reliability Council of Texas, or ERCOT, and the PUC may have had at their disposal during the crisis.
The comments were notable because Lt. Gov. Dan Patrick and the Senate have fought with Abbott and the House over $16 billion in overcharges that, according to an independent market monitor, wrongly accrued near the end of the Feb. 15-19 outages.
Sen. Charles Schwertner, R-Georgetown, said the commission’s former chairwoman, DeAnn Walker, and Bill Magness, president of ERCOT, decided to hold the high cap in place because there “was still great concern about grid stability, even though there was significant reserves.”
He pressed McAdams to call that incorrect, which McAdams did.
“Given the fact pattern that I’m privy to, senator,” it wasn’t the right move, he said. “But again, there may be other facts out there. There probably are.”
McAdams acknowledged many homeowners and businesses were traumatized.
“The public’s confidence in the ability of the PUC to effectively regulate our electric markets has been badly damaged and shaken,” he said.
McAdams spoke favorably of renewable energy, calling wind and solar “absolutely valuable resources,” as the electricity sector faces profound change nationwide. To whatever extent those are not available, the PUC should “firm that up” with “dispatchable forms of generation,” such as gas, coal and nuclear, McAdams said.
He also called for lawmakers to consider providing electricity market bailout through “securitization,” or low-interest bond financing, to rural electric co-ops that were unable to pay the massive wholesale power bills they racked up during the February crisis.
“It would prevent those systems from having to front-load those costs onto their own members and smooth that out over a term of years,” while preventing an “uplift” of costs to other market participants who wisely hedged against soaring prices, McAdams said.
Noting that more than 400 bills have been filed to change ERCOT and how it’s governed, and as Texans prepare to vote on grid modernization funding this year, McAdams told the Senate panel, “It is clear to me that the Legislature wants meaningful changes to the status quo – to ensure that something positive comes out of this tragedy.”
Lake, who if confirmed by the Senate would replace Arthur D’Andrea as PUC chairman, grew up in Tyler. He attended prep school in New England and earned an undergraduate degree from the University of Chicago and a master of business administration degree from Stanford University.
He then worked for a commodities trading firm, a behavioral health company and as a business consultant before he became director of business development for Tyler-based Lake Ronel Oil Co. in 2014.
In late 2015, Abbott named Lake to the Texas Water Development Board and in February 2018 picked him to be the chairman of the three-member board that seeks to ensure water supplies for a fast-growing state.
Lake has steered the water board as it rolled out additional loans for water projects, approved by the Legislature and voters in 2013, and took the lead after Hurricane Harvey on flood control planning and infrastructure financing.
He’s posted exuberantly on Twitter as he toured agricultural water installations, lakes in West Texas and river authorities.
If confirmed, Lake and McAdams each would make $189,500 a year.
Toyota and Honda Moving e delivers hydrogen backup power via a fuel cell bus, portable batteries, and power exporters for disaster relief, emergency electricity, and grid outage support near charging stations and microgrids.
Key Points
A hydrogen mobile power system using a fuel cell bus and batteries to supply emergency electricity during disasters.
✅ Fuel cell bus outputs up to 18 kW, 454 kWh capacity
✅ Portable batteries and power exporter deliver site power
✅ Supports disaster relief near hydrogen charging stations
Without the uninterrupted supply of power and electricity, modern economies would be unable to function. A blackout can impact everything from transport to health care, communication, and even water supplies, as seen in a near-blackout in Japan that strained the grid. It is one of the key security concerns for every government on earth, a point underscored by Fatih Birol on electricity options during the pandemic, and the growth in the market for backup power reflects that fact. In 2018, the global Backup Power market was $14.9 billion and is expected to reach $22 billion by the end of 2025, growing at a CAGR of 5.0 percent between 2019 and 2025.
It is against this backdrop that Toyota and Honda have come up with a new and innovative solution to providing electricity during disasters. The two transport giants have launched a mobile power generation system that consists of a fuel cell bus that can carry a large amount of hydrogen, aligned with Japan's hydrogen energy system efforts underway, portable external power output devices, and portable batteries to disaster zones. The system, which is called ‘Moving e’ includes Toyota’s charging station fuel cell bus, Honda’s power exporter 9000 portable external power output device, two types of Honda’s portable batteries, and a Honda Mobile Power Pack Charge & Supply Concept charger/discharger for MPP.
In simple terms, the bus would drive to a disaster zone, and while other approaches such as gravity energy storage are advancing, the portable batteries and power output devices would be used to extract electricity from the fuel cell bus and provide it wherever it is needed. The bus itself can generate 454kWh and has a maximum output of 18kW. That is more than enough energy to supply electricity for large indoor areas such as an evacuation area. The bus is also fitted with space for people to nap or rest during a disaster.
The two companies plan to test the effectiveness of the Moving e at multiple municipalities and businesses. These locations will have to be within 100km of a hydrogen station that is capable of refueling the bus. If the bus has to drive 200km, then its electricity supply to the disaster zone would drop from 490kwh to 240kWh. While there aren’t currently enough hydrogen stations to make this a realistic scenario for all disaster zones, especially as countries push for hydrogen-ready power plants in Germany and related infrastructure, hydrogen is growing increasingly competitive with gasoline and diesel.
While gas generators are still considered more reliable and generally cheaper than backup batteries for home use, cleaner backup power is growing increasingly popular, and novel storage like power-to-gas in Europe is also advancing across grids. This latest development by Toyota and Honda is another step forward for the battery and fuel cell industry, with initiatives like PEM hydrogen R&D in China accelerating progress, – especially considering the meteoric rise of hydrogen energy in recent years.
Hybrid renewable energy projects integrate wind, solar, and battery storage to enhance grid reliability, reduce curtailment, and provide dispatchable power in markets like Alberta, leveraging photovoltaic tracking, overbuilt transformers, and improved storage economics.
Key Points
Hybrid renewable energy projects combine wind, solar, and storage to deliver reliable, dispatchable clean power.
✅ Combine wind, solar, and batteries for steady, dispatchable output
✅ Lower curtailment by using shared transformers and smart inverters
✅ Boost farm income via leases; diversify risk from oil and gas
Third-generation farmer James Praskach has been burned by the oil and gas sector and watched wicked weather pound his crops flat, but he is hoping a new kind of energy -- the renewable kind -- will pay dividends.
The 39-year-old is part of a landowner consortium that is hosting the sprawling 300-megawatt Blackspring Ridge wind power project in southeastern Alberta.
He receives regular lease payments from the $600-million project that came online in 2014, even though none of the 166 towering wind turbines that surround his land are actually on it.
His lease payments stand to rise, however, when and if the proposed 77-MW Vulcan Solar project, which won regulatory approval in 2016, is green-lighted by developer EDF Renewables Inc.
The panels would cover about 400 hectares of his family's land with nearly 300,000 photovoltaic solar panels in Alberta, installed on racks designed to follow the sun. It would stand in the way of traditional grain farming of the land, but that wouldn't have been a problem this year, Praskach says.
"This year we actually had a massive storm roll through. And we had 100 per cent hail damage on all of (the Vulcan Solar lands). We had canola, peas and barley on it this year," he said, adding the crop was covered by insurance.
Meanwhile, poor natural gas prices and a series of oilpatch financial failures mean rents aren't being paid for about half of the handful of gas wells on his land, showing how a province that is a powerhouse for both fossil and green energy can face volatility -- he's appealed to the Alberta surface Rights Board for compensation.
"(Solar power) would definitely add a level of security for our farming operations," said Praskach.
Hybrid power projects that combine energy sources are a growing trend as selling renewable energy gains traction across markets. Solar only works during the day and wind only when it is windy so combining the two -- potentially with battery storage or natural gas or biomass generation -- makes the power profile more reliable and predictable.
Globally, an oft-cited example is on El Hierro, the smallest of the Canary Islands, where wind power is used to pump water uphill to a reservoir in a volcanic crater so that it can be released to provide hydroelectric power when needed. At times, the project has provided 100 per cent of the tiny island's energy needs.
Improvements in technology such as improving solar and wind power and lower costs for storage mean it is being considered as a hybrid add-on for nearly all of its renewable power projects, said Dan Cunningham, manager of business development at Greengate Power Corp. of Calgary.
Grant Arnold, CEO of developer BluEarth Renewables, agreed.
"The barrier to date, I would say, has been cost of storage but that is changing rapidly," he said. "We feel that wind and storage or solar and storage will be a fundamental way we do business within five years. It's changing very, very rapidly and it's the product everybody wants."
Vulcan Solar was proposed after Blackspring Ridge came online, said David Warner, associate director of business development for EDF Renewables, which now co-owns the wind farm with Enbridge Inc.
"Blackspring actually had incremental capacity in the main power transformers," he said. "Essentially, it was capable of delivering more energy than Blackspring was producing. It was overbuilt."
Vulcan Solar has been sized to utilize the shortfall without producing so much energy that either will ever have to be constrained, he said. Much of the required environmental work has already been done for the wind farm.
Storage is being examined as a potential addition to the project but implementing it depends on the regulatory system. At present, Alberta's regulators are still working on how to permit and control what they call "dispatchable renewables and storage" systems.
EDF announced last spring it would proceed with the Arrow Canyon Solar Project in Nevada which is to combine 200 MW of solar with 75 MW of battery storage by 2022 -- the batteries are to soak up the sun's power in the morning and dispatch the electricity in the afternoon when Las Vegas casinos' air conditioning is most needed.
What is clear is that renewable energy will continue to grow, with Alberta renewable jobs expected to follow -- in a recent report, the International Energy Agency said global electricity capacity from renewables is set to rise by 50 per cent over the next five years, an increase equivalent to adding the current total power capacity of the United States.
The share of renewables is expected to rise from 26 per cent now to 30 per cent in 2024 but will remain well short of what is needed to meet long-term climate, air quality and energy access goals, it added.
Germany Energy Price Defensive Shield counters soaring gas and electricity costs with a gas price brake, VAT cut, subsidies for households and SMEs, LNG terminals, renewables, temporary nuclear extension, and targeted borrowing to curb inflation.
Key Points
A 200 billion euro package to cap energy costs, subsidize basics, and stabilize inflation for firms and households.
✅ Gas price brake and VAT cut reduce consumer and SME energy bills.
✅ Temporary electricity subsidies and nuclear extension aid winter supply.
✅ Funded via new borrowing; supports LNG and renewable expansion.
German Chancellor Olaf Scholz set out a 200 billion euro ($194 billion) "defensive shield", including a gas price brake and a cut in sales tax for the fuel, to protect companies and households from the impact of soaring energy prices in Germany.
Europe's biggest economy is trying to cope with surging gas and electricity costs, with local utilities seeking help, caused largely by a collapse in Russian gas supplies to Europe, which Moscow has blamed on Western sanctions following its invasion of Ukraine in February.
3 minute readSeptember 29, 202211:35 AM PDTLast Updated 6 days ago Germany agrees 200 bln euro package to shield against surging energy prices By Holger Hansen and Kirsti Knolle
"Prices have to come down, so the government will do everything it can. To this end, we are setting up a large defensive shield," said Scholz.
Under the plans, to run until spring 2024, the government will introduce an emergency price brake on gas, the details of which will be announced next month, while Europe weighs emergency measures to limit electricity prices across the bloc. It is scrapping a planned gas levy meant to help firms struggling with high spot market prices.
A temporary electricity price brake will subsidise basic consumption for consumers and small and medium-sized companies, and complements an electricity subsidy for industries under discussion. Sales tax on gas will fall to 7% from 19%.
In its efforts to cut its dependence on Russian energy, Germany is also promoting the expansion of renewable energy and developing liquefied gas terminals, but rolling back European electricity prices remains complex.
To help households and companies weather any winter supply disruption, amid rising heating and electricity costs this winter, especially in southern Germany, two nuclear plants previously due to close by the end of this year will be able to keep running until spring 2023.
The package will be financed with new borrowing this year, as Berlin makes use of the suspension of a constitutionally enshrined limit on new debt of 0.35% of gross domestic product.
Finance Minister Christian Lindner has said he wants to comply with the limit again next year, even as the EU outlines gas price cap strategies for the market.
Lindner, of the pro-business Free Democrats (FDP) who share power with Scholz's Social Democrats and the Greens, said on Thursday the country's public finances were stable.
"We can put it no other way: we find ourselves in an energy war," said Lindner. "We want to clearly separate crisis expenditure from our regular budget management, we want to send a very clear signal to the capital markets."
He also said the steps would act as a brake on inflation, which hit its highest level in more than a quarter of century in September.
Opposition conservative Markus Soeder, premier of the southern state of Bavaria, said the steps gave the right signal.
"It gives industry and citizens confidence that we can get through the winter," he said.
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.
