Zambia, Africa's largest producer of copper, has suffered chronic power shortages and breakdowns over the past few decades. In the last days of April, it was reported that the country's National Tender Board was finalizing plans to offer an international tender for the development of the Kafue Gorge hydropower station.
A day later, it was announced that two generators had collapsed at the power station, putting further pressure on the load-shedding program that the Zambia Electricity Supply Corporation (Zesco) is already implementing.
A company spokesperson said that the generators would be up again in two days and that power imports from the Democratic Republic of Congo had not been received for days because of transmission faults, causing the to machines to kick out. Maintenance on the other two generators at Kafue had been carried out 10 days previously.
The new tender is aimed at improving capacity and generating efficiency in the country, which has the capacity to produce 1,600 megawatts (MW) but only produces 1,000 MW because of the lack of investment in the maintenance and optimization of the plant. Kafue has the potential to output 750 MW, and it is estimated that $1 billion investment is required to develop the plant to that level and assist in the increase of power to the country's copper mines that are forecast to produce a possible 1 million tons of copper by 2010.
Some mines are reported have offered six future investments in the development project.
Zesco and Tata Africa Holdings of South Africa (Mumbai/Johannesburg) have issued an international tender for a $230 million power station. The partners have formed Itezhi-Tezhi Power Corporation (ITPC) to manage the construction of the 120 MW project, which is scheduled to be commissioned in June 2012. Bids are invited for the design, supply, construction and commissioning of the project.
Road, housing and water and sanitation contracts will be scheduled for completion by March 2009. ITPC will seek loans from financial institutions to meet part of the costs.
A national output of 2,500 MW will be needed by 2013 to cope with the requirements of the growing mining industry. Zesco is in negotiation with Japanese, Indian and international financial institution to raise $600 million for system upgrades and the ITPC development.
Ermineskin First Nation Solar Project delivers a 1 MW distributed generation array with 3,500 panels, selling power to Alberta's grid, driving renewable energy revenue, jobs, and regional economic development with partner SkyFire Energy.
Key Points
A 1 MW, 3,500-panel distributed generation plant selling power to Alberta's grid to support revenue and jobs.
✅ Annual revenue projected at $80k-$150k, scalable
✅ Built with SkyFire Energy; expansion planned next summer
The switch will soon be flipped on a solar energy project that will generate tens of thousands of dollars for Ermineskin First Nation, while energizing economic development across Alberta, where selling renewables is emerging as a promising opportunity.
Built on six acres, the one-megawatt generator and its 3,500 solar panels will produce power to be sold into the province’s electrical grid, providing annual revenues for the band of $80,000 to $150,000, depending on energy demand and pricing.
The project cost $2.7 million, including connection costs and background studies, said Sam Minde, chief executive officer of the band-owned Neyaskweyahk Group of Companies Inc.
It was paid for with grants from the Western Economic Diversification Fund and the province’s Climate Leadership Plan, and, amid Ottawa’s green electricity contracting push, is expected to be connected to the grid by mid-December.
“It’s going to be the biggest distributed generation in Alberta,” he said.
Called the Sundancer generator, it was built and will be operated through a partnership with SkyFire Energy, reflecting how renewable power developers design better projects by combining diverse resources.
Minde said the project’s benefits extend beyond Ermineskin First Nation, one of four First Nations at Maskwacis, 20 km north of Ponoka, in a province where renewable energy surge could power thousands of jobs.
“Our nation is looking to do the best it can in business. It’s competitive, but at the same time, what is good for us is good for the region.
“If we’re creating jobs, we’re going to be building up our economy. And if you look at our region right now, we need to continue to create opportunities and jobs.”
Electricity prices are rock bottom right now, in the six to nine cents per kilowatt hour range, with recent Alberta solar contracts coming in below natural gas on cost. During the oilsands boom, when power demand was skyrocketing, the price was in the 16 to 18 cent range.
That means there is a lot of room for bigger returns for Ermineskin in the future, especially if pipelines such as TransMountain get going or the oilsands pick up again, and as Alberta solar growth accelerates in the years ahead.
The band is so confident that Sundancer will prove a success that there are plans to double it in size, a strategy echoed by community-scale efforts such as the Summerside solar project that demonstrate scalability. By next summer, a $1.5-million to $1.7-million project funded by the band will be built on another six acres nearby.
Minde said the project is an example of the community’s connection with the environment being used to create opportunities and embracing technologies that will likely figure large in the world’s energy future.
Wisconsin Solar and Wind Energy advances as rooftop solar, utility-scale farms, and NREL perovskite solar cells improve efficiency; wind turbines gain via wake modeling, yaw control, and grid-scale battery storage to cut carbon emissions.
Key Points
It is Wisconsin's growth in rooftop and utility-scale solar plus optimized wind turbines to cut carbon emissions.
✅ Perovskite solar cells promise higher efficiency, need longevity
✅ Wake modeling and yaw control optimize wind farm output
✅ Batteries and bids can offset reliance on natural gas
Solar energy in Wisconsin continued to grow in 2019, as more homeowners had rooftop panels installed and big utilities started building multi-panel solar farms.
Wind power is increasing more slowly in the state. However, renewable power developers are again coming forward with proposals for multiple turbines.
Nationally, researchers are working on ways to get even more energy from solar and wind, with the U.S. moving toward 30% electricity from wind and solar in coming years, as states like Wisconsin aim to reduce their carbon emissions over the next few decades.
One reason solar energy is growing in Wisconsin is due to the silicon panels becoming more efficient. But scientists haven't finished trying to improve panel efficiency. The National Renewable Energy Laboratory (NREL) in Golden, Col., is one of the research facilities experimenting with brushing a lab-made solution called perovskite onto a portion of a panel called a solar cell.
In a demonstration video supplied by NREL, senior scientist Maikel van Hest said that, in the lab anyway, the painted cell and its electrical connections called contacts, produce more energy:
"There you go! That's how you paint a perovskite solar cell. And you imagine that ultimately what you could do is you could see a company come in with a truck in front of your house and they would basically paint on the contacts first, dry those, and paint the perovskite over it. That you would have photovoltaic cells on the side of your house, put protective coating on it, and we're done."
Another NREL scientist, David Moore, says the new solar cells could be made faster and help meet what's expected to be a growing global demand for energy. However, Moore says the problem has been lack of stability.
"A solar cell with perovskites will last a couple years. We need to get that to 20-25 years, and that's the big forefront in perovskite research, is getting them to last longer," Moore told members of the Society of Environmental Journalists during a recent tour of NREL.
Another part of improving renewable energy is making wind turbines more productive. At NREL's Insight Center, a large screen showing energy model simulations dominates an otherwise darkened room. Visualization scientist Nicholas Brunhart-Lupo points to a display on the screen that shows how spinning turbines at one edge of a wind farm can cause an airflow called a wake, which curtails the power generation of other turbines.
"So what we find in these simulations is these four turbines back here, since they have this used air, this low-velocity wake being blown to their faces, they're only generating about 20% of the energy they should be generating," he explains.
Brunhart-Lupo says the simulations can help wind farm developers with placement of turbines as well as adjustments to the rotor and blades called the yaw system.
Continued progress with renewables may be vital to any state or national pledges to reduce use of fossil fuels and carbon emissions linked to climate change, including Biden's solar expansion plan as a potential pathway. Some scientists say to limit a rise in global temperature, there must be a big decline in emissions by 2050.
But even utilities that say they support use of more renewables, as why the grid isn't 100% renewable yet makes clear, aren't ready to let go of some energy sources. Jonathan Adelman of Xcel Energy, which serves part of Western Wisconsin, says Xcel is on track to close its last two coal-fired power plants in Minnesota. But he says the company will need more natural gas plants, even though they wouldn't run as often.
"It's not perfect. And it is in conflict with our ultimate goal of being carbon-free," says Adelman. "But if we want to facilitate the transition, we still need resources to help that happen."
Some in the solar industry would like utilities that say they need more natural gas plants to put out competitive bids to see what else might be possible. Solar advocates also note that in some states, energy regulators still favor the utilities.
Meanwhile, solar slowly marches ahead, including here in southeastern Wisconsin, as Germany's solar power boost underscores global momentum.
On the roof of a ranch-style home in River Hills, a work crew from the major solar firm Sunrun recently installed mounting brackets for solar panels.
Sunrun Public Policy Director Amy Heart says she supports research into more efficient renewables. But she says another innovation may have to come in the way regulators think.
"Instead of allowing and thinking about from the perspective of the utility builds the power plant, they replace one plant with another one, they invest in the infrastructure; is really thinking about how can these distributed solutions like rooftop solar, peer-to-peer energy sharing, and especially rooftop solar paired with batteries how can that actually reduce some of what the utility needs?
Large-scale energy storage batteries are already being used in some limited cases. But energy researchers continue to make improvements to them, too, with cheap solar batteries beginning to make widespread adoption more feasible as scientists race to reduce the expected additional harm of climate change.
Bay of Fundy Tidal Energy advances as Nova Scotia permits Jupiter Hydro to test floating barge platforms with helical turbines in Minas Passage, supporting renewable power, grid-ready pilots, and green jobs in rural communities.
Key Points
A Nova Scotia tidal energy project using helical turbines to generate clean power and create local jobs.
✅ Permits enable 1-2 MW prototypes near Minas Passage
✅ Floating barge platforms with patented helical turbines
✅ PPA at $0.50/kWh with Nova Scotia Power
An Alberta-based company has been granted permission to try to harness electricity from the powerful tides of the Bay of Fundy.
Nova Scotia has issued two renewable energy permits to Jupiter Hydro.
Backers have long touted the massive energy potential of Fundy's tides -- they are among the world's most powerful -- but large-scale commercial efforts to harness them have borne little fruit so far, even as a Scottish tidal project recently generated enough power to supply nearly 4,000 homes elsewhere.
The Jupiter application says it will use three "floating barge type platforms" carrying its patented technology. The company says it uses helical turbines mounted as if they were outboard motors.
"Having another company test their technology in the Bay of Fundy shows that this early-stage industry continues to grow and create green jobs in our rural communities," Energy and Mines Minister Derek Mombourquette said in a statement.
The first permit allows the company to test a one-megawatt prototype that is not connected to the electricity grid.
The second -- a five-year permit for up to two megawatts -- is renewable if the company meets performance standards, environmental requirements and community engagement conditions.
Mombourquette also authorized a power purchase agreement that allows the company to sell the electricity it generates to the Nova Scotia grid through Nova Scotia Power for 50 cents per kilowatt hour.
On its web site, Jupiter says it believes its approach "will prove to be the most cost effective marine energy conversion technology in the world," even as other regional utilities consider initiatives like NB Power's Belledune concept for turning seawater into electricity.
The one megawatt unit would have screws which are about 5.5 metres in diameter.
The project is required to obtain all other necessary approvals, permits and authorizations.
It will be located near the Fundy Ocean Research Center for Energy in the Minas Passage and will use existing electricity grid connections.
A study commissioned by the Offshore Energy Research Association of Nova Scotia says by 2040, the tidal energy industry could contribute up to $1.7 billion to Nova Scotia's gross domestic product and create up to 22,000 full-time jobs, a transition that some argue should be planned by an independent body to ensure reliability.
Last month, Nova Scotia Power said it now generates 30 per cent of its power from renewables, as the province moves to increase wind and solar projects after abandoning the Atlantic Loop.
The utility says 18 per cent came from wind turbines, nine per cent from hydroelectric and tidal turbines and three per cent by burning biomass across its fleet.
However, over half of the province's electrical generation still comes from the burning of coal or petroleum coke, even as environmental advocates push to reduce biomass use in the mix. Another 13 per cent come from burning natural gas and five per cent from imports.
New England Solar Interconnection Costs highlight distributed generation strains, transmission charges, distribution upgrades, and DAF fees as National Grid maps hosting capacity, driving queue delays and FERC disputes in Rhode Island and Massachusetts.
Key Points
Rising upfront grid upgrade and DAF charges for distributed solar in RI and MA, including some transmission costs.
✅ Upfront grid upgrades shifted to project developers
✅ DAF and transmission charges increase per MW costs
✅ Queue delays tied to hosting capacity and cluster studies
Solar developers in Rhode Island and Massachusetts say soaring charges to interconnect with the electric grid are threatening the viability of projects.
As more large-scale solar projects line up for connections, developers are being charged upfront for the full cost of the infrastructure upgrades required, a long-common practice that they say is now becoming untenable amid debates over a new solar customer charge in Nova Scotia.
“It is a huge issue that reflects an under-invested grid that is not ready for the volume of distributed generation that we’re seeing and that we need, particularly solar,” said Jeremy McDiarmid, vice president for policy and government affairs at the Northeast Clean Energy Council, a nonprofit business organization.
Connecting solar and wind systems to the grid often requires upgrades to the distribution system to prevent problems, such as voltage fluctuations and reliability risks highlighted by Australian distributors in their networks. Costs can vary considerably from place to place, depending on the amount of distributed generation coming online and the level of capacity planning by regulators, said David Feldman, a senior financial analyst at the National Renewable Energy Laboratory.
“Certainly the Northeast often has more distribution challenges than much of the rest of the country just because it’s more populous and often the infrastructure is older,” he said. “But it’s not unique to the Northeast — in the Midwest, for example, there’s a significant amount of wind projects in the queues and significant delays.”
In Rhode Island and Massachusetts, where strong incentive programs are driving solar development, the level of solar coming online is “exposing the under-investment in the distribution system that is causing these massive costs that National Grid is assigning to particular projects or particular groups of projects,” McDiarmid said. “It is going to be a limiting factor for how much clean energy we can develop and bring online.”
Frank Epps, chief executive officer at Energy Development Partners, has been developing solar projects in Rhode Island since 2010. In that time, he said, interconnection charges on his projects have grown from about $80,000-$120,000 per megawatt to more than $400,000 per megawatt. He attributed the increase to a lack of investment in the distribution network by National Grid over the last decade.
He and other developers say the utility is now adding further to their costs by passing along not just the cost of improving the distribution system — the equivalent of the city street of the grid that brings power directly to customers — but also costs for modifying the transmission system — the interstate highway that moves bulk power over long distances to substations.
Solar developers who are only requesting to hook into the distribution system, and not applying for transmission service, say they should not be charged for those additional upgrades under state interconnection rules unless they are properly authorized under the federal law that governs the transmission system.
A Rhode Island solar and wind developer filed a complaint with the Federal Energy Regulatory Commission in February over transmission system improvement charges for its four proposed solar projects. Green Development said National Grid subsidiaries Narragansett Electric and New England Power Company want to charge the company more than $500,000 a year in operating and maintenance expenses assessed as so-called direct assignment facility charges.
“This amount nearly doubles the interconnection costs associated with the projects,” which total 38.4 megawatts in North Smithfield, the company says in its complaint. “Crucially, these charges are linked to recovering costs associated with providing transmission service — even though no such transmission service is being provided to Green Development.”
But Ted Kresse, a spokesperson for National Grid, said the direct assignment facility, or DAF, construct has been in place for decades and has been applied to any customer affecting the need for transmission upgrades.
“It is the result of the high penetration and continued high volume of distributed generation interconnections that has recently prompted the need for transmission upgrades, and subsequently the pass-through of the associated DAF charges,” he said.
Several complaints before the Rhode Island Public Utilities Commission object to these DAF and other transmission charges.
One petition for dispute resolution concerns four solar projects totaling 40 MW being developed by Energy Development Partners in a former gravel pit in North Kingstown. Brown University has agreed to purchase the power.
The developer signed interconnection service agreements with Narragansett Electric in 2019 requiring payment of $21.6 million for costs associated with connecting the projects at a new Wickford Junction substation. Last summer, Narragansett sought to replace those agreements with new ones that reclassified a portion of the costs as transmission-level costs, through New England Power, National Grid’s transmission subsidiary.
That shift would result in additional operational and maintenance charges of $835,000 per year for the estimated 35-year life of the projects, the complaint says.
“This came as a complete shock to us,” Epps said. “We’re not just paying for the maintenance of a new substation. We are paying a share of the total cost that the system owner has to own and operate the transmission system. So all of the sudden, it makes it even tougher for distributed energy resources to be viable.”
In its response to the petition, National Grid argues that the charges are justified because the solar projects will require transmission-level upgrades at the new substation. The company argues that the developer should be responsible for the costs rather than ratepayers, “who are already supporting renewable energy development through their electric rates.”
Seth Handy, one of the lawyers representing Green Development in the FERC complaint, argues that putting transmission system costs on distribution assets is unfair because the distributed resources are “actually reducing the need to move electricity long distances. We’ve been fighting these fights a long time over the underestimating of the value of distributed energy in reducing system costs.”
Handy is also representing the Episcopal Diocese of Rhode Island before the state Supreme Court in its appeal of an April 2020 public utilities commission order upholding similar charges for a proposed 2.2-megawatt solar project at the diocese’s conference center and camp in Glocester.
Todd Bianco, principal policy associate at the utilities commission, said neither he nor the chairperson can comment on the pending dockets contesting these charges. But he noted that some of these issues are under discussion in another docket examining National Grid’s standards for connecting distributed generation. Among the proposals being considered is the appointment of an independent ombudsperson to resolve interconnection disputes.
Separately, legislation pending before the Rhode Island General Assembly would remove responsibility for administering the interconnection of renewable energy from utilities, and put it under the authority of the Rhode Island Infrastructure Bank, a financing agency.
Handy, who recently testified in support of the bill, said he believes National Grid has too many conflicting interests to administer interconnecting charges in a timely, transparent and fair fashion, and pointed to utility moves such as changes to solar compensation in other states as examples. In particular, he noted the company’s interests in expanding natural gas infrastructure.
“There are all kinds of economic interests that they have that conflict with our state policy to provide lower-cost renewable energy and more secure energy solutions,” Handy said.
In testimony submitted to the House Committee on Corporations opposing the legislation, National Grid said such powers are well beyond the purpose and scope of the infrastructure bank. And it cited figures showing Rhode Island is third in the country for the most installed solar per square mile (behind New Jersey and Massachusetts).
Nadav Enbar, program manager at the Electric Power Research Institute, a nonprofit research organization for the utility industry, said interconnection delays and higher costs are becoming more common due to “the incredible uptake” in distributed renewable energy, particularly solar.
That’s impacting hosting capacity, the room available to connect all resources to a circuit without causing adverse harm to reliability and safety.
“As hosting capacity is being reduced, it’s causing an increasing number of situations where utilities need to study their systems to guarantee interconnection without compromising their systems,” he said. “And that is the reason why you’re starting to see some delays, and it has translated into some greater costs because of the need for upgrades to infrastructure.”
The cost depends on the age or absence of infrastructure, projected load growth, the number of renewable energy projects in the queue, and other factors, he said. As utilities come under increasing pressure to meet state renewable goals, and as some states pilot incentives like a distributed energy rebate in Illinois to drive utility innovation, some (including National Grid) are beginning to provide hosting capacity maps that provide detailed information to developers and policymakers about the amount of distributed energy that can be accommodated at various locations on the grid, he said.
In addition, the coming availability of high-tech “smart inverters” should help ease some of these problems because they provide the grid with more flexibility when it comes to connecting and communicating with distributed energy resources, Enbar said.
In Massachusetts, the Department of Public Utilities has opened a docket to explore ways to better plan for and share the cost of upgrading distribution infrastructure to accommodate solar and other renewable energy sources as part of a grid overhaul for renewables nationwide. National Grid has been conducting “cluster studies” there that attempt to analyze the transmission impacts of a group of solar projects and the corresponding interconnection cost to each developer.
Kresse, of National Grid, said the company favors cost-sharing methodologies under consideration that would “provide a pathway to spread cost over the total enabled capacity from the upgrade, as opposed to spreading the cost over only those customers in the queue today.”
Solar developers want regulators to take an even broader approach that factors in how the deployment of renewables and the resulting infrastructure upgrades benefit not just the interconnecting generator, but all customers.
“Right now, if your project is the one that causes a multimillion-dollar upgrade, you are assigned that cost even though that upgrade is going to benefit a lot of other projects, as well as make the grid stronger,” said McDiarmid, of the clean energy council. “What we’re asking for is a way of allocating those costs among a variety of developers, as well as to the grid itself, meaning ratepayers. There’s a societal benefit to increasing the modernization of the grid, and improving the resilience of the grid.”
In the meantime, BlueHub Capital, a Boston-based solar developer focused on serving affordable housing developments, recently learned from National Grid that, as a part of one of the area studies, it will be required to pay $5.8 million in transmission and distribution upgrades to interconnect a 2-megawatt solar-plus-storage project that leverages cheaper batteries to enhance resilience, approved for a brownfield site in Gardner, Massachusetts.
According to testimony submitted to the department, the sum is supposed to be paid within the next year, even though the project will have to wait to be interconnected until April 2027, when a new transmission line is completed. In addition, BlueHub will be responsible for DAF charges totaling $3.4 million over the 20-year life of the project.
“We’re being asked to pay a fortune to provide solar that the state wants,” said DeWitt Jones, BlueHub’s president. “It’s so expensive that the upgrades are driving everyone out of the interconnection queue. The costs stay the same, but they fall on fewer projects. We need a process of grid design and modernization to guide this.”
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.
PG&E Camp Fire Guilty Plea underscores involuntary manslaughter charges as the utility admits sparking Paradise's wildfire; Butte County prosecution, CAL FIRE findings, bankruptcy oversight, victim compensation trust, and safety reforms shape accountability.
Key Points
The legal admission by PG&E to 84 involuntary manslaughter counts and unlawfully starting the 2018 Camp Fire.
✅ $3,486,950 fine, $500,000 DA costs; no prison terms.
✅ $13.5B victim trust, Paradise and Butte County payments.
California utility Pacific Gas and Electric Company pleaded guilty Tuesday to 84 counts of involuntary manslaughter and one count of unlawfully starting the Camp Fire, the deadliest blaze in the state's history.
Butte County District Attorney Michael L. Ramsey said the "historic moment" should be a signal that corporations will be held responsible for "recklessly endangering" lives. The 84 people "did not need to die," Ramsey said. He said the deaths were "of the most unimaginable horror, being burned to death."
Before sentencing, survivors will testify Wednesday about the losses of their loved ones, and many have pursued lawsuits against the utility seeking accountability.
No individuals will be sent to prison, Ramsey said.
"This is the first time that PG&E or any major utility has been charged with homicide as the result of a reckless fire. It killed a town," Ramsey said, referring to Paradise, which was annihilated by the blaze. According to court documents filed in March, the company will be fined "no more than $3,486,950," and it must reimburse the Butte County District Attorney's Office $500,000 for the costs of its investigation into the blaze, and under separate oversight a federal judge ordered dividends to be directed to wildfire risk reduction to prioritize safety.
Among other provisions, PG&E must establish a trust, compensating victims of the 2018 Camp Fire and other wildfires to the tune of $13.5 billion as part of its bankruptcy plan, according to the plea agreement included in a regulatory filing. It has to pay hundreds of millions to the town of Paradise and Butte County and cooperate with prosecutors' investigation, the plea deal says. PG&E also waived its right to appeal.
"I have heard the pain and the anguish of victims as they've described the loss they continue to endure, and the wounds that can't be healed," PG&E Corporation CEO and President Bill Johnson said after the plea. "No words from me could ever reduce the magnitude of such devastation or do anything to repair the damage. But I hope that the actions we are taking here today will help bring some measure of peace, including aid through a Wildfire Assistance Program the company announced."
Johnson was in court Tuesday, where Butte County Superior Court Judge Michael Deems read the names of each victim as their photos were shown on a screen, CNN affiliate KTLA reported. Johnson said the utility would never put profits ahead of safety again. He told the judge that PG&E took responsibility for the devastation "with eyes wide open to what happened and to what must never happen again," KTLA reported.
In March, the utility and the state agreed to bankruptcy terms, which included an overhaul of PG&E's board selection process, financial structure and oversight, with rates expected to stabilize in 2025 as reforms take hold. According to investigators with the California Department of Forestry and Fire Protection, PG&E was responsible for the devastating Camp Fire.
Electrical lines owned and operated by PG&E started the fire November 8, 2018, CAL Fire said in a news release, after the company acknowledged its power lines may have started two fires that day.
"The tinder dry vegetation and Red Flag conditions consisting of strong winds, low humidity and warm temperatures promoted this fire and caused extreme rates of spread," CAL Fire said. PG&E had previously said it was "probable" that its equipment started the Camp Fire but that it wasn't conclusive whether its lines ignited a second fire, as CAL Fire alleged. The power company filed for bankruptcy in January 2019 as it came under pressure from billions of dollars in claims tied to deadly wildfires, and other utilities such as Southern California Edison have faced similar lawsuits.
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