A local bike repairman brought a new lifestyle idea to the Homer Farmers' Market recently: Why not use bike pedal power to blend a smoothie instead of electricity?
Here's a food blender with strawberries and juice. Here's a bike and here's an inverter box for the electricity. Curious crowds drew in for a closer look.
"I think a lot of locals knew of this, but were happy to see it out in the public eye," said Chase Warren, who sold the smoothies for $6 each. "The tourists seemed more amused. But we all live here in Homer, and a lot of us like to see this technology as practical."
Something tasty to show for the mechanical process proved a good way of illustrating the possibilities.
"Our intent at the market is to get people thinking about the possibilities of pedal power, to realize that, in fact, pedal power is the most efficient transferral of mechanical energy from one form to another, calorie for calorie, than any other I know," said Derek Reynolds of CycleLogical, a bike repair shop by the Kachemak Gear Shed.
He rents a booth at the market. The bicycle-powered smoothie operation is by no means an original idea, Reynolds said.
"You can find people doing this all over the world. The idea to try this at our local market came from my friends Chase (Warren) and Haley, who saw it in Hawaii and thought it was awesome and a perfect fit for our Market booth. I thought they were right so we went for it," he said.
There are a couple different means to use pedal power, Reynolds explains. Some, such as the XtraCycle's Fender Blender use a direct drive set up whereby the power from pedaling the crank is directly transferred mechanically to the blender or whatever machine you can think of that is stationary and requires a spinning motion, such as a washer or dryer. The idea has been applied to light bulbs and any number of low-watt appliances. But those aren't as interesting to illustrate as a food blender producing a little instant satisfaction a person can sample right there at the market.
There's some technical information and equipment to master, but Reynolds and friends say it's not too difficult for most to grasp. After all, at one time the concept of turning an electrical switch may have seemed more complicated to people than lighting an oil lamp.
"Our set up at the Homer Farmer's Market is indirect, in that the power produced by the spinning of the wheel is transferred to a DC generator motor via a belt and is then stored in a battery that is tied into an AC/DC converter, into which you can plug any given appliance you desire, provided the total wattage isn't more than we can produce while pedaling," he wrote in an e-mail.
Best off, the end product is clean energy. Except for the production of the motor and other gadgets, no oil, coal or natural gas was burned to produce that power.
"No rivers dammed, no holes dug, just a strong pair of legs is all it takes," Reynolds summarized.
Nigeria Electricity Crisis undermines energy access as aging grid, limited generation, and transmission losses cause power outages, raising costs for businesses and public services; renewables, microgrids, and investment offer resilient, inclusive solutions.
Key Points
A nationwide power gap from weak infrastructure, low generation, and grid losses that disrupt services and growth.
✅ Aging grid and underinvestment drive frequent power outages
✅ Businesses face higher costs, lost productivity, weak competitiveness
✅ Renewables, microgrids, and regulatory reform can expand access
In Nigeria, millions of residents face persistent challenges with access to reliable electricity, a crisis that has profound implications for businesses, public services, and overall socio-economic development. This article explores the root causes of Nigeria's electricity deficit, drawing on 2021 electricity lessons to inform analysis, its impact on various sectors, and potential solutions to alleviate this pressing issue.
Challenges with Electricity Access
The issue of inadequate electricity access in Nigeria is multifaceted. The country's electricity generation capacity falls short of demand due to aging infrastructure, inadequate maintenance, and insufficient investment in power generation and distribution, a dynamic echoed when green energy supply constraints emerge elsewhere as well. As a result, many Nigerians, particularly in rural and underserved urban areas, experience frequent power outages or have limited access to electricity altogether.
Impact on Businesses
The unreliable electricity supply poses significant challenges to businesses across Nigeria. Manufacturing industries, small enterprises, and commercial establishments rely heavily on electricity to operate machinery, maintain refrigeration for perishable goods, and power essential services. Persistent power outages disrupt production schedules, increase operational costs, and, as grids prepare for new loads from electric vehicle adoption worldwide, hinder business growth and competitiveness in both domestic and international markets.
Public Services Strain
Public services, including healthcare facilities, schools, and government offices, also grapple with the consequences of Nigeria's electricity crisis. Hospitals rely on electricity to power life-saving medical equipment, maintain proper sanitation, and ensure patient comfort. Educational institutions require electricity for lighting, technological resources, and administrative functions. Without reliable power, the delivery of essential public services is compromised, impacting the quality of education, healthcare outcomes, and overall public welfare.
Socio-economic Impact
The electricity deficit in Nigeria exacerbates socio-economic disparities and hampers poverty alleviation efforts, even as debates continue over whether access alone reduces poverty in every context. Lack of access to electricity limits economic opportunities, stifles entrepreneurship, and perpetuates income inequality. Rural communities, where access to electricity is particularly limited, face greater challenges in accessing educational resources, healthcare services, and economic opportunities compared to urban counterparts.
Government Initiatives and Challenges
The Nigerian government has implemented various initiatives to address the electricity crisis, including privatization of the power sector, investment in renewable energy projects, and regulatory reforms aimed at improving efficiency and accountability, while examples like India's village electrification illustrate rapid expansion potential too. However, progress has been slow, and challenges such as corruption, bureaucratic inefficiencies, and inadequate funding continue to impede efforts to expand electricity access nationwide.
Community Resilience and Adaptation
Despite these challenges, communities and businesses in Nigeria demonstrate resilience and adaptability in navigating the electricity crisis. Some businesses invest in alternative power sources such as generators, solar panels, or hybrid systems to mitigate the impact of power outages, while utilities weigh shifts signaled by EVs' impact on utilities for future planning. Community-led initiatives, including local cooperatives and microgrids, provide decentralized electricity solutions in underserved areas, promoting self-sufficiency and resilience.
Path Forward
Addressing Nigeria's electricity crisis requires a concerted effort from government, private sector stakeholders, and international partners, informed by UK grid transformation experience as well. Key priorities include increasing investment in power infrastructure, enhancing regulatory frameworks to attract private sector participation, and promoting renewable energy deployment. Improving energy efficiency, reducing transmission losses, and expanding electricity access to underserved communities are critical steps towards achieving sustainable development goals and improving quality of life for all Nigerians.
Conclusion
The electricity crisis in Nigeria poses significant challenges to businesses, public services, and socio-economic development. Addressing these challenges requires comprehensive strategies that prioritize infrastructure investment, regulatory reform, and community empowerment. By working together to expand electricity access and promote sustainable energy solutions, Nigeria can unlock its full economic potential, improve living standards, and create opportunities for prosperity and growth across the country.
Community Solar for Low-Income Homes expands energy equity by delivering renewable energy access, predictable bill savings, and tax credit benefits to renters and energy-insecure households, accelerating distributed generation and storage adoption nationwide.
Key Points
A program model enabling renters and LMI households to subscribe to off-site solar and save on utility bills.
✅ Earn bill credits from shared solar generation.
✅ Expands access for renters and LMI subscribers.
✅ Often paired with storage and IRA tax credit adders.
On a square-foot basis, the issue of inequality is made worse by higher costs for energy usage in the nation. Efforts like community solar programs such as Maryland community solar are underway to boost low-income participation in the cost benefits of renewable energy.
The Energy Information Administration (EIA) shows that households that are considered energy insecure, or those that have the inability to adequately meet basic household energy costs, are paying more for electricity than their wealthier counterparts.
On average in the United States in 2020, households were billed about $1.04 per square foot for all energy sources. For homes that did not report energy insecurity, that average was $0.98 per square foot, while homes with energy insecurity issues paid an average of $1.24 per square foot for energy. This means that U.S. residents that need the most support on their energy bills are stuck with costs 27% higher than their neighbors on square-foot-basis.
EIA said energy-insecure households have reduced or forgone basic necessities to pay energy bills, kept their houses at unsafe temperatures because of energy cost concerns, or been unable to repair heating or cooling equipment because of cost.
In 2020, households with income less than $10,000 a year were billed an average of $1.31 per square foot for energy, while households making $100,000 or more were billed an average of $0.96 per square foot, said EIA. Renters paid considerably more ($1.28 per square foot) than owners ($0.98 per square foot). There were also considerable differences between regions, with New England solar growth sparking grid upgrade debates, ethnic groups and races, and insulation levels, as seen below.
The energy transition toward renewables like solar has offered price stability, amid record solar and storage growth nationwide, but thus far energy-insecure communities have relatively been left behind. A recent Berkeley Lab report, Residential Solar-Adopter Income and Demographic Trends, indicates that even though the rate of solar adoption among low-income residents is increasing (from 5% in 2010 to 11% in 2021), that segment of energy consumers remains under-represented among solar adopters, relative to its share of the population.
Community solar efforts
As such, the United States is targeting communities most impacted by energy costs that have not benefitted from the transition, highlighting “Energy Communities” that are eligible for an additional 10% tax credit through funds made possible by the Inflation Reduction Act.
Additionally, a push for community solar development is taking place nationwide to extend access to affordable solar energy to renters and other residents that aren’t able to leverage finances to invest in predictable, low-cost residential solar systems. The Biden Administration set a goal this year to sign up 5 million community solar households, achieving $1 billion in bill savings by 2025. The community solar model only represents about 8% of the total distributed solar capacity in the nation. This target would entail a jump from 3 GW installed capacity to 20 GW by the target year. The Department of Energy estimates community solar subscribers save an average of 20% on their bills.
California this year passed AB 2316, the Community Renewable Energy Act takes aim at four acute problems in the state’s power market: reliability amid rising outage risks, rates, climate and equity. The law creates a community renewable energy program, including community solar-plus-storage, supported by cheaper batteries, to overcome access barriers for nearly half of Californians who rent or have low incomes. Community solar typically involves customers subscribing to an off-site solar facility, receiving a utility bill credit for the power it generates.
“Community renewable energy is a proven powerful tool to help close California’s clean energy gap, bringing much needed relief to millions struggling with high housing costs and utility debt,” said Alexis Sutterman, energy equity program manager at the California Environmental Justice Alliance.
The program has energy equity baked into its structure, working to make sure Californians of all income levels participate in the benefits of the energy transition. Not only does it open solar access to renters, the law ensures that at least 51% of subscribers are low-income customers, which is expected to make projects eligible for a 10% tax credit adder under the IRA.
“The money’s on the table now,” said Jeff Cramer, president and chief executive of the Coalition for Community Solar Access. “While there are groups pushing for solar access for all, and states with strong legislation, there are other pockets of interest in surprising places in the United States. For example, Louisiana has no policy for community solar or support for low-income residents going solar but the city of New Orleans has its own utility commission with a community solar program. In Nebraska, forward-looking co-operatives have created community solar projects.
Community solar markets are active in 22 states, with more expected to come online in the future as states pursue 100% clean energy targets across the country. However, the market is expected to require strong community outreach efforts to foster trust and gain subscribers.
“There is a distrust of community solar initially in LMI communities as many have been burned before by retail energy false promises,” said Eric LaMora, executive director, community solar, Nautilus Solar on a panel at the Solar Energy Industries Association Finance, Tax, and Buyers seminar. “People are suspicious but there really are no hooks with community solar.”
LMI residents are leery to provide tax records or much documents at all in order to sign up for community solar, LaMora said. “We were surprised to see less of a default rate with LMI residents. We attribute this to the fact that they see significant savings on their electric bill, making it easier to pay each month,” he said.
Florida Solar for All Opt-Out highlights Gov. DeSantis rejecting EPA grant funds under the Inflation Reduction Act, limiting low-income households' access to solar panels, clean energy programs, and promised electricity savings across disadvantaged communities.
Key Points
Florida Solar for All Opt-Out is the state declining EPA grants, restricting low-income access to solar energy savings.
✅ EPA grant under IRA aimed at low-income solar
✅ Estimated 20% electricity bill savings missed
✅ Florida lacks PPAs and renewable standards
Florida has passed up on up to $400 million in federal money that would have helped low-income households install solar panels.
A $7 billion grant “competition” to promote clean energy in disadvantaged communities by providing low-income households with access to affordable solar energy was introduced by President Joe Biden earlier this year, and despite his climate law's mixed results in practice, none of that money will reach Florida households.
The Environmental Protection Agency announced the competition in June as part of Biden’s Inflation Reduction Act. However, Florida Gov. Ron DeSantis has decided to pass on the $400 million up for grabs by choosing to opt out of the opportunity.
Inflation Reduction Act:What is the Inflation Reduction Act? Everything to know about one of Biden's big laws
The program would have helped Florida households reduce their electricity costs by a minimum of 20% during a key time when Floridians are leaving in droves due to a rising cost of living associated with soaring insurance costs, inflation, and proposed FPL rate hikes statewide.
Florida was one of six other states that chose not to apply for the money.
President Joe Biden announced a $7 billion “competition” to promote clean energy in disadvantaged communities.
The opportunity, named “Solar for All,” was announced by the EPA in June and promised to provide up to $7 billion in grants to states, territories, tribal governments, municipalities, and nonprofits to expand the number of low-income and disadvantaged communities primed for residential solar investment — enabling millions of low-income households to access affordable, resilient and clean solar energy.
The grant is intended to help lower energy costs for families, create jobs and help reduce greenhouse effects that accelerate global climate change by providing financial support and incentives to communities that were previously locked out of investments.
How much money would Floridians save under the ‘Solar for All’ solar panel grant?
The program aims to reduce household electricity costs by at least 20%. Florida households paid an average of $154.51 per month for electricity in 2022, just over 14% of the national average of $135.25, and debates over hurricane rate surcharges continue to shape customer bills, according to the U.S. Energy Information Administration. A 20% savings would drop those bills down to around $123 per month.
On the campaign trail, DeSantis has pledged to unravel Biden’s green energy agenda if elected president, amid escalating solar policy battles nationwide, slamming the Inflation Reduction Act and what he called “a concerted effort to ramp up the fear when it comes to things like global warming and climate change.”
His energy agenda includes ending Biden’s subsidies for electric cars while pushing policies that he says would ramp up domestic oil production.
“The subsidies are going to drive inflation higher,” DeSantis said at an event in September. “It’s not going to help with interest rates, and it is certainly not going to help with our unsustainable debt levels.”
DeSantis heading to third debate:As he enters third debate, Ron DeSantis has a big Nikki Haley problem
DeSantis’ plan to curb clean energy usage in Florida seems to be at odds with the state as a whole, and the region's evolving strategy for the South underscores why it has been ranked among the top three states to go solar since 2019, according to the Solar Energy Industries Association (SEIA).
SEIA also shows, however, that Florida lags behind many other states when it comes to solar policies, as utilities tilt the solar market in ways that influence policy outcomes statewide. Florida, for instance, has no renewable energy standards, which are used to increase the use of renewable energy sources for electricity by requiring or encouraging suppliers to provide customers with a stated minimum share of electricity from eligible renewable resources, according to the EIA.
Power purchase agreements, which can help lower the cost of going solar through third-party financing, are also not allowed in Florida, with court rulings on monopolies reinforcing the existing market structure. And there have been other policies implemented that drove other potential solar investments to other states.
Manitoba Hydro Court Ruling affirms the Public Utilities Board exceeded its jurisdiction by ordering a First Nations rate class, overturning an electricity rates appeal tied to geography, poverty, and regulatory authority in Manitoba.
Key Points
A decision holding the PUB lacked authority to create a First Nations rate class, restoring uniform electricity pricing.
✅ Equalized electricity pricing reaffirmed across Manitoba
✅ Geography, not poverty, found decisive in unlawful rate class
Manitoba Hydro was wrongly forced to create a new rate class for electricity customers living on First Nations, the Manitoba Court of Appeal has ruled.
The court decided the Public Utilities Board "exceeded its jurisdiction" by mandating Indigenous customers on First Nations could have a different electricity rate from other Manitobans.
The board made the order in 2018, which exempted those customers from the general rate increase that year of 3.6 per cent.
"The directive constituted the creation and implementation of general social policy, an area outside of the PUB's jurisdiction and encroaching into areas that are better suited to the federal and provincial government," says the decision, which was released Tuesday.
Hydro's appeal of the PUB's decision went to court earlier this year.
At the time, the Crown corporation acknowledged many Indigenous people on First Nations live in poverty, but it argued the Public Utilities Board was overstepping its authority in trying to address the issue by creating a new rate class.
It also argued it was against provincial law to charge different rates in different areas of the province.
The PUB, however, insisted that legislation gives it the right to decide which factors are relevant when considering electricity prices, such as social issues.
Special Manitoba Hydro rate class needed to offset challenges of living on First Nations, appeal court hears Manitoba Hydro can appeal order to create special First Nation rate The board had heard evidence that some customers were making "unacceptable" sacrifices to keep the lights on each month.
Decision 'heavy-handed': AMC The Assembly of Manitoba Chiefs, an intervener in the appeal, had backed the utility board's position. It said on-reserve customers are disproportionately vulnerable to rate hikes over time.
Grand Chief Arlen Dumas said Wednesday he was surprised by the court's ruling.
"I will be speaking with my federal and provincial counterparts on how we deal with this issue, because I think it's the wrong [decision]. It's heavy-handed and we need to address it."
The appeal court judges said there is past precedent for setting equal electricity rates, regardless of where customers live. Legislation to that effect was made in the early 2000s and a few years ago, the PUB recognized that geographical limitations should not be imposed on a class of customers.
Since the board's new order didn't extend the same savings to First Nations members who don't live on reserve but face similar financial circumstances, it is clear the deciding factor was geography, rather than poverty or treaty status, the judges said.
Manitoba Hydro temporarily cutting 200 jobs, many of them front-line workers "In my view, the PUB erred in law when it created an on-reserve class based solely on a geographic region of the province in which customers are located," the decision read.
While Manitoba Hydro objected to the PUB's order in 2018, it still devoted money to create the new customer class.
Spokesperson Bruce Owen said the utility is still studying the impact of the court's decision, but it appreciates the ruling.
"We all recognize that many people on First Nations have challenges, but our argument was solely on whether or not the PUB had the authority to create a special rate class based on where people live."
Owen added that Hydro recognizes electricity rates can be a hardship on individuals facing poverty. He said those considerations are part of the discussions the corporation has with the utilities board.
Ontario Energy Storage Procurement accelerates grid flexibility as IESO seeks lithium batteries, pumped storage, compressed air, and flywheels to balance renewables, support EV charging, and complement gas peakers during Pickering refits and rising electricity demand.
Key Points
Ontario's plan to procure 2,500 MW of storage to firm renewables, aid EV charging, and add flexible grid capacity.
✅ 2,500 MW storage plus 1,500 MW gas for 2025-2027 reliability
✅ Enables VPPs via EVs, demand response, and hybrid solar-storage
Ontario is staring down an electricity supply crunch and amid a rush to secure more power, it is plunging into the world of energy storage — a relatively unknown solution for the grid that experts say could also change energy use at home.
Beyond the sprawling nuclear plants and waterfalls that generate most of the province’s electricity sit the batteries, the underground caverns storing compressed air to generate electricity, and the spinning flywheels waiting to store energy at times of low demand and inject it back into the system when needed.
The province’s energy needs are quickly rising, with the proliferation of electric vehicles and growing Canada-U.S. collaboration on EV adoption, and increasing manufacturing demand for electricity on the horizon just as a large nuclear plant that supplies 14 per cent of Ontario’s electricity is set to be retired and other units are being refurbished.
The government is seeking to extend the life of the Pickering Nuclear Generating Station, planning an import agreement for power with Quebec, rolling out conservation programs, and — controversially — relying on more natural gas to fill the looming gap between demand and supply, amid Northern Ontario sustainability debates.
Officials with the Independent Electricity System Operator say a key advantage of natural gas generation is that it can quickly ramp up and down to meet changes in demand. Energy storage can provide that same flexibility, those in the industry say.
Energy Minister Todd Smith has directed the IESO to secure 1,500 megawatts of new natural gas capacity between 2025 and 2027, along with 2,500 megawatts of clean technology such as energy storage that can be deployed quickly, which together would be enough to power the city of Toronto.
It’s a far cry from the 54 megawatts of energy storage in use in Ontario’s grid right now.
Smith said in an interview that it’s the largest active procurement for energy storage in North America.
“The one thing that we want to ensure that we do is continue to add clean generation as much as possible, and affordable and clean generation that’s reliable,” he said.
Rupp Carriveau, director of the Environmental Energy Institute at the University of Windsor, said the timing is good.
“The space is there, the technology is there, and the willingness among private industry to respond is all there,” he said. “I know of a lot of companies that have been rubbing their hands together, looking at this potential to construct storage capacity.”
Justin Rangooni, the executive director of Energy Storage Canada, said because of the relatively tight timelines, the 2,500 megawatts is likely to be mostly lithium batteries. But there are many other ways to store energy, other than a simple battery.
“As we get to future procurements and as years pass, you’ll start to see possibly pump storage, compressed air, thermal storage, different battery chemistry,” he said.
Pump storage involves using electricity during off-peak periods to pump water into a reservoir and slowly releasing it to run a turbine and generate electricity when it’s needed. Compressed air works similarly, and old salt caverns in Goderich, Ont., are being used to store the compressed air.
In thermal storage, electricity is used to heat water when demand is low and when it’s needed, water stored in tanks can be used as heat or hot water.
Flywheels are large spinning tops that can store kinetic energy, which can be used to power a turbine and produce electricity. A flywheel facility in Minto, Ont., also installed solar panels on its roof and became the first solar storage hybrid facility in Ontario, said a top IESO official.
Katherine Sparkes, the IESO’s director of innovation, research and development, said it’s exciting, from a grid perspective.
“As we kind of look to the future and we think about gas phase out and electrification, one of the big challenges that all power systems across North America and around the world are looking at is: how do you accommodate increasing amounts of variable, renewable resources and just make better use of your grid assets,” she said.
“Hybrids, storage generation pairings, gives you that opportunity to deal with the variability of renewables, so to store electricity when the sun isn’t shining, or the wind isn’t blowing, and use it when you need it to.”
The small amount of storage already in the system provides more fine tuning of the electricity system, whereas 2,500 megawatts will be a more “foundational” part of the toolkit, said Sparkes.
But what’s currently on the grid is far from the only storage in the province. Many commercial and industrial consumers, such as large manufacturing facilities or downtown office buildings, are using storage to manage their electricity usage, relying on battery energy when prices are high.
The IESO sees that as an opportunity and has changed market rules to allow those customers to sell electricity back to the grid when needed.
As well, the IESO has its eye on the thousands of mobile batteries in electric vehicles, a trend seen in California, that shuttle people around the province every day but sit unused for much of the time.
“If we can enable those batteries to work together in aggregation, or work with other types of technologies like solar or smart building systems in a configuration, like a group of technologies, that becomes a virtual power plant,” Sparkes said.
Peak Power, a company that seeks to “make power plants obsolete,” is running a pilot project with electric vehicles in three downtown Toronto office buildings in which the car batteries can provide electricity to reduce the facility’s overall demand during peak periods using vehicle-to-building charging with bidirectional chargers.
In that model, one vehicle can earn $8,000 per year, said cofounder and chief operating officer Matthew Sachs.
“Battery energy storage will change the energy industry in the same way and for the same reasons that refrigeration changed the milk industry,” he said.
“As you had refrigeration, you could store your commodity and that changed the distribution channels of it. So I believe that energy storage is going to radically change the distribution channels of energy.”
If every home has a solar panel, an electric vehicle and a residential battery, it becomes a generating station, a decentralization that’s not only more environmentally friendly, but also relies less on “monopolized utilities,” Sachs said.
In the next decade, energy demand from electric vehicles is projected to skyrocket, making vehicle-to-grid integration increasingly relevant, and Sachs said the grid can’t grow enough to accommodate a peak demand of hundreds of thousands of vehicles being plugged in to charge at the end of the workday commute. Authorities need to be looking at more incentives such as time-of-use pricing and price signals to ensure the demand is evened out, he said.
“It’s a big risk as much as it’s a big opportunity,” he said. “If we do it wrong, it will cost us billions to fix. If we do it right, it can save us billions.”
Jack Gibbons, the chair of the Ontario Clean Air Alliance, said the provincial and federal governments need to fund and install bidirectional chargers in order to fully take advantage of electric vehicles.
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.
