When thinking of wind turbines, it's natural to picture the wide-open and windswept plains of the West. And when picturing rows of solar panels glinting in the sun, it's the cloud-free skies of the Southwest that come to mind.
But the Chicago area, with all its unpredictable weather and intermittent bouts of sunshine, features its own growing center of alternative energy research. Surprisingly enough, this hot spot for wind and solar power is just 80 miles west of Chicago.
Economic development officials along the I-39 corridor have tapped into the growing alternative energy field with investment in wind energy and solar power facilities.
"The counties along I-39 are very open for business and several of them are open to wind farm projects," says Janyce Fadden, executive director of the I-39 Logistics Corridor Association.
The corridor has spawned five significant wind farm deals since 2003. The first of these was the $56 million Mendota Hills Wind Farm in Lee County near the village of Paw Paw. The latest to come on line, Chicago-based Invenergy LLC's Grand Ridge Wind Energy Center, is located just south of the town of Marseilles in LaSalle County. The total energy output of the 66 turbines is estimated at 315 million kilowatt hours per year, enough to power 33,000 single-family homes.
Three other projects have been approved and are either under construction or preparing to begin. NextEra Energy Resources plans to begin construction this year on a $400 million Wind Energy Center that straddles DeKalb and Lee Counties. Top Crop Wind Farm by Horizon Wind Energy, which is a unit of the Portuguese utility company, Energias de Portugal Renovaveis, S.A., has begun a project that will be built throughout Grundy and Livingston Counties. When completed, the farm will generate 600 megawatts per month.
To put that in perspective, Mendota Hills Wind Farm is capable of 51.66 megawatts per month, which enough to power about 13,000 homes.
And lastly, the 67-turbine EcoGrove Wind LLC Wind Farm in Stephenson County is nearly completed.
However, in the current political climate, it may be a safe bet that these will not be the last projects to find a home along the I-39 corridor. $16.8 billion of the American Recovery and Reinvestment Act will be appropriated for the Department of Energy's Office of Efficiency and Renewable Energy (EERE) programs and initiatives.
President Obama has made energy one of the three key initiatives in to his economic recovery plan.
Likewise, the State of Illinois has set specific standards that should engender more development in the near future. The state has pledged that 10 percent of its electricity will come from renewable sources by 2012 and 25 percent by 2025.
To ensure that more companies continue to pursue development opportunities, the state has guaranteed that energy from wind sources will be purchased by local providers.
"In Illinois, distribution is separate from production of power," says Fadden. "In northern Illinois, Com Ed is obligated to take power from Mendota Hills onto its grid. It can then buy it and resell it or someone somewhere else can buy it off the grid. Someone in California could be buying that power."
Wind farms are not the only developments to gain traction along the I-39 corridor. Seizing upon the momentum of alternative energy, the city of Rockford has recently completed a deal with Wanxiang, a Hangzhou-based Chinese company with U.S. headquarters in Elgin, to develop a manufacture plant for photovoltaic solar-energy panels. The first phase of the project would consist of a 40,000-square-foot facility, which could eventually be expanded to 160,000-square-feet. The facility is projected to employ 250 people.
The firm preformed a nationwide search before settling on Rockford, says Fadden.
The major incentive for Wanxiang is that the city agreed to build a 100-acre solar farm just south of the regional airport. The farm will use panels produced at the Wanxiang manufacturing facility. The solar farm will produce approximately 10 Megawatts of electric power, which is sufficient to supply 3,300 average residential homes.
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.
Siwash Creek Hydroelectric Project faces downsizing under a BC Hydro power purchase agreement, with run-of-river generation, high grid interconnection costs, First Nations partnership, and surplus electricity from Site C reshaping clean energy procurement.
Key Points
A downsized run-of-river plant in BC, co-owned by Kanaka Bar and Green Valley, selling power via a BC Hydro PPA.
✅ Approved at 500 kW under a BC Hydro clean-energy program
✅ Grid interconnection initially quoted at $2.1M
✅ Joint venture: Kanaka Bar and Green Valley Power
A small run-of-river hydroelectric project recently selected by B.C. Hydro for a power purchase agreement may no longer be financially viable.
The Siwash Creek project was originally conceived as a two-megawatt power plant by the original proponent Chad Peterson, who holds a 50-per-cent stake through Green Valley Power, with the Kanaka Bar Indian Band holding the other half.
The partners were asked by B.C. Hydro to trim the capacity back to one megawatt, but by the time the Crown corporation announced its approval, it agreed to only half that — 500 kilowatts — under its Standing Order clean-energy program.
“Hydro wanted to charge us $2.1 million to connect to the grid, but then they said they could reduce it if we took a little trim on the project,” said Kanaka Bar Chief Patrick Michell.
The revenue stream for the band and Green Valley Power has been halved to about $250,000 a year. The original cost of running the $3.7-million plant, including financing, was projected to be $273,000 a year, according to the Kanaka Bar economic development plan.
“By our initial forecast, we will have to subsidize the loan for 20 years,” said Michell. “It doesn’t make any sense.”
The Kanaka Band has already invested $450,000 in feasibility, hydrology and engineering studies, with a similar investment from Green Valley.
B.C. Hydro announced it would pursue five purchase agreements last March with five First Nations projects — including Siwash Creek — including hydro, solar and wind energy projects, as two new generating stations were being commissioned at the time. A purchase agreement allows proponents to sell electricity to B.C. Hydro at a set price.
However, at least ten other “shovel-ready” clean energy projects may be doomed while B.C. Hydro completes a review of its own operations and its place in the energy sector, where legal outcomes like the Squamish power project ruling add uncertainty, including B.C.’s future power needs.
With the 1,100-megawatt Site C Dam planned for completion in 2024, and LNG demand cited to justify it, B.C. Hydro now projects it will have a surplus of electricity until the early 2030s.
Even if British Columbians put 300,000 electric vehicles on the road over the next 12 years, amid BC Hydro’s first call for power, they will require only 300 megawatts of new capacity, the company said.
A long-term surplus could effectively halt all small-scale clean energy development, according to Clean Energy B.C., even as Hydro One’s U.S. coal plant remains online in the region.
“(B.C. Hydro) dropped their offer down to 500 kilowatts right around the time they announced their review,” said Michell. “So we filled out the paperwork at 500 kilowatts and (B.C. Hydro) got to make its announcement of five projects.”
In the new few weeks, Kanaka and Green Valley will discuss whether they can move forward with a new financial model or shelve the project, he said.
B.C. Hydro declined to comment on the rationale for downsizing Siwash Creek’s power purchase agreement.
The Kanaka Bar Band successfully operates a 49.9-megawatt run-of-river plant on Kwoiek Creek with partners Innergex Renewable Energy.
Black Hills Energy Corriedale Wind Farm Expansion earns regulatory approval in Wyoming, boosting capacity to over 52MW near Cheyenne with five turbines, supporting Renewable Ready customers and wind power goals under PUC and PSC oversight.
Key Points
An approved Wyoming wind project upgrade to over 52MW, adding five turbines to serve Renewable Ready customers.
✅ Adds 12.5MW via five new wind turbines near Cheyenne
✅ Cost increases to $79m; prior estimate $57m
✅ Approved by SD PUC after Wyoming PSC review
US company Black Hills Energy has received regulatory approval to increase the size of its Corriedale wind farm in Wyoming, where Wyoming wind exports to California are advancing, to over 52MW from 40MW previously.
The South Dakota Public Utilities Commission approved the additional 12.5MW capacity after the Wyoming Public Service Commission determined the boost was within commission rules, as federal initiatives like DOE wind energy awards continue to support the sector.
Black Hills Energy will install five additional turbines, raising the project cost to $79m from $57m, amid growing heartland wind investment across the region. Corriedale will be built near Cheyenne and is expected to be placed in service in late 2020.
Black Hills said that during the initial subscription period for its Renewable Ready program, applications of interest from eligible commercial, industrial and governmental agency customers were received in excess of the program's 40MW, underscoring the view that more energy sources can make stronger projects.
Black Hills Corporations chief executive and president Linden Evans said: “We are pleased with the opportunity to expand our Renewable Ready program, allowing us to meet our customers’ interest in renewable wind energy, which co-op members increasingly support.
“This innovative program expands our clean energy portfolio while meeting our customers’ evolving needs, particularly around cleaner and more sustainable energy, as projects like new energy generation coming online demonstrate.”
Atlantic Clean Power Superhighway outlines a federally backed transmission grid upgrade for Atlantic Canada, adding 2,000 MW of renewable energy via interprovincial ties, improved hydro access from Quebec and Newfoundland and Labrador, with utility-regulator funding.
Key Points
A federal-provincial plan upgrading Atlantic Canada's grid to deliver 2,000 MW of renewables via interprovincial links.
✅ $2M technical review to rank priority transmission projects
✅ Target: add 2,000 MW renewable power to Atlantic grid
✅ Cost-sharing by utilities, regulators, and federal-provincial funding
The federal government will spend $2 million on an engineering study to improve the Atlantic region's electricity grid.
The study was announced Friday at a news conference held by 10 federal and provincial politicians at a meeting of the Atlantic Growth Strategy in Halifax, which includes ongoing regulatory reform efforts for cleaner power in Atlantic Canada.
The technical review will identify the most important transmission projects including inter-provincial ties needed to move electricity across the region.
Nova Scotia Premier Stephen McNeil said the results are expected in July.
Provinces will apply to the federal government for federal funding to build the infrastructure. Utilities in each province will be expected to pay some portion of the cost by applying to respective regulators, but what share falls to ratepayers is not known.
Federal Intergovernmental Affairs Minister Dominic LeBlanc characterized the grid improvements as something that will cost hundreds of millions of dollars.
"We have a historic opportunity to quickly get to work on upgrading ultimately a whole series of transmission links of inter-provincial ties. That's something that the government of Canada would be anxious to work with in terms of collaborating with the provinces on getting that right."
Premier McNeil referred specifically to improving hydro access from Quebec and Newfoundland and Labrador.
For context, a massive cross-border hydropower line to New York is planned, illustrating the scale of projects under consideration.
Goal of 2,000 megawatts
McNeil said the goal was to bring an additional 2,000 megawatts of renewable electricity into the region.
"I can't stress to you enough how critical this will be for the future economic success and stability of Atlantic Canada, especially as Atlantic grids face intensifying storms," he said.
Federal Immigration Minister Ahmed Hussen also announced a pilot project to attract immigrant workers will be extended by two years to the end of 2021.
International graduate students will be given 24 months to apply under the program — a one-year increase.
Smart EV Charging orchestrates vehicle-to-grid (V2G), demand response, and fast charging to balance the power grid, integrating renewables, electrolyzers for hydrogen, and megawatt chargers for fleets with advanced control and co-optimization.
Key Points
Smart EV charging coordinates EV load to stabilize the grid, cut peaks, and integrate renewable energy efficiently.
✅ Reduces peak demand via coordinated, flexible load control
✅ Enables V2G services with renewables and battery storage
✅ Supports megawatt fast charging for heavy-duty fleets
As electric vehicle (EV) sales continue to rev up in the United States, the power grid is in parallel contending with the greatest transformation in its 100-year history: the large-scale integration of renewable energy and power electronic devices. The expected expansion of EVs will shift those challenges into high gear, causing cities to face gigawatt-growth in electricity demand, as analyses of EV grid impacts indicate, and higher amounts of variable energy.
Coordinating large numbers of EVs with the power system presents a highly complex challenge. EVs introduce variable electrical loads that are highly dependent on customer behavior. Electrified transportation involves co-optimization with other energy systems, like natural gas and bulk battery storage, including mobile energy storage flexibility for new operational options. It could involve fleets of automated ride-hailing EVs and lead to hybrid-energy truck stops that provide hydrogen and fast-charging to heavy-duty vehicles.
Those changes will all test the limits of grid integration, but the National Renewable Energy Laboratory (NREL) sees opportunity at the intersection of energy systems and transportation. With powerful resources for simulating and evaluating complex systems, several NREL projects are determining the coordination required for fast charging, balancing electrical supply and demand, and efficient use of all energy assets.
Smart and Not-So-Smart Control To appreciate the value of coordinated EV charging, it is helpful to imagine the opposite scenario.
"Our first question is how much benefit or burden the super simple, uncoordinated approach to electric vehicle charging offers the grid," said Andrew Meintz, the researcher leading NREL's Electric Vehicle Grid Integration team, as well as the RECHARGE project for smart EV charging. "Then we compare that to the 'whiz-bang,' everything-is-connected approach. We want to know the difference in value."
In the "super simple" approach, Meintz explained that battery-powered electric vehicles grow in market share, exemplified by mass-market EVs, without any evolution in vehicle charging coordination. Picture every employee at your workplace driving home at 5 p.m. and charging their vehicle. That is the grid's equivalent of going 0 to 100 mph, and if it does not wreck the system, it is at least very expensive. According to NREL's Electrification Futures Study, a comprehensive analysis of the impacts of widespread electrification across all U.S. economic sectors, in 2050 EVs could contribute to a 33% increase in energy use during peak electrical demand, underscoring state grid challenges that make these intervals costly when energy reserves are procured. In duck curve parlance, EVs will further strain the duck's neck.
The Optimization and Control Lab's Electric Vehicle Grid Integration bays allow researchers to determine how advanced high power chargers can be added safely and effectively to the grid, with the potential to explore how to combine buildings and EV charging. Credit: Dennis Schroeder, NREL Meintz's "whiz-bang" approach instead imagines EV control strategies that are deliberate and serve to smooth, rather than intensify, the upcoming demand for electricity. It means managing both when and where vehicles charge to create flexible load on the grid.
At NREL, smart strategies to dispatch vehicles for optimal charging are being developed for both the grid edge, where consumers and energy users connect to the grid, as in RECHARGEPDF, and the entire distribution system, as in the GEMINI-XFC projectPDF. Both projects, funded by the U.S. Department of Energy's (DOE's) Vehicle Technologies Office, lean on advanced capabilities at NREL's Energy Systems Integration Facility to simulate future energy systems.
At the grid edge, EVs can be co-optimized with distributed energy resources—small-scale generation or storage technologies—the subject of a partnership with Eaton that brought industry perspectives to bear on coordinated management of EV fleets.
At the larger-system level, the GEMINI-XFC project has extended EV optimization scenarios to the city scale—the San Francisco Bay Area, to be specific.
"GEMINI-XFC involves the highest-ever-fidelity modeling of transportation and the grid," said NREL Research Manager of Grid-Connected Energy Systems Bryan Palmintier.
"We're combining future transportation scenarios with a large metro area co-simulationPDF—millions of simulated customers and a realistic distribution system model—to find the best approaches to vehicles helping the grid."
GEMINI-XFC and RECHARGE can foresee future electrification scenarios and then insert controls that reduce grid congestion or offset peak demand, for example. Charging EVs involves a sort of shell game, where loads are continually moved among charging stations to accommodate grid demand.
But for heavy-duty vehicles, the load is harder to hide. Electrified truck fleets will hit the road soon, creating power needs for electric truck fleets that translate to megawatts of localized demand. No amount of rerouting can avoid the requirements of charging heavy-duty vehicles or other instances of extreme fast-charging (XFC). To address this challenge, NREL is working with industry and other national laboratories to study and demonstrate the technological buildout necessary to achieve 1+ MW charging stationsPDF that are capable of fast charging at very high energy levels for medium- and heavy-duty vehicles.
To reach such a scale, NREL is also considering new power conversion hardware based on advanced materials like wide-bandgap semiconductors, as well as new controllers and algorithms that are uniquely suited for fleets of charge-hungry vehicles. The challenge to integrate 1+ MW charging is also pushing NREL research to higher power: Upcoming capabilities will look at many-megawatt systems that tie in the support of other energy sectors.
Renewable In-Roads for Hydrogen
At NREL, the drive toward larger charging demands is being met with larger research capabilities. The announcement of ARIES opens the door to energy systems integration research at a scale 10-times greater than current capabilities: 20 MW, up from 2 MW. Critically, it presents an opportunity to understand how mobility with high energy demands can be co-optimized with other utility-scale assets to benefit grid stability.
"If you've got a grid humming along with a steady load, then a truck requires 500 kW or more of power, it could create a large disruption for the grid," said Keith Wipke, the laboratory program manager for fuel cells and hydrogen technologies at NREL.
Such a high power demand could be partially served by battery storage systems. Or it could be hidden entirely with hydrogen production. Wipke's program, with support from the DOE's Hydrogen and Fuel Cell Technologies Office, has been performing studies into how electrolyzers—devices that use electricity to break water into hydrogen and oxygen—could offset the grid impacts of XFC. These efforts are also closely aligned with DOE's H2@Scale vision for affordable and effective hydrogen use across multiple sectors, including heavy-duty transportation, power generation, and metals manufacturing, among others.
"We're simulating electrolyzers that can match the charging load of heavy-duty battery electric vehicles. When fast charging begins, the electrolyzers are ramped down. When fast charging ends, the electrolyzers are ramped back up," Wipke said. "If done smoothly, the utility doesn't even know it's happening."
NREL Researchers Rishabh Jain, Kazunori Nagasawa, and Jen Kurtz are working on how grid integration of electrolyzers—devices that use electricity to break water into hydrogen and oxygen—could offset the grid impacts of extreme fast-charging. Credit: National Renewable Energy Laboratory As electrolyzers harness the cheap electrons from off-demand periods, a significant amount of hydrogen can be produced on site. That creates a natural energy pathway from discount electricity into a fuel. It is no wonder, then, that several well-known transportation and fuel companies have recently initiated a multimillion-dollar partnership with NREL to advance heavy-duty hydrogen vehicle technologies.
"The logistics of expanding electric charging infrastructure from 50 kW for a single demonstration battery electric truck to 5,000 kW for a fleet of 100 could present challenges," Wipke said. "Hydrogen scales very nicely; you're basically bringing hydrogen to a fueling station or producing it on site, but either way the hydrogen fueling events are decoupled in time from hydrogen production, providing benefits to the grid."
The long driving range and fast refuel times—including a DOE target of achieving 10-minutes refuel for a truck—have already made hydrogen the standout solution for applications in warehouse forklifts. Further, NREL is finding that distributed electrolyzers can simultaneously produce hydrogen and improve voltage conditions, which can add much-needed stability to a grid that is accommodating more energy from variable resources.
Those examples that co-optimize mobility with the grid, using diverse technologies, are encouraging NREL and its partners to pursue a new scale of systems integration. Several forward-thinking projects are reimagining urban mobility as a mix of energy solutions that integrate the relative strengths of transportation technologies, which complement each other to fill important gaps in grid reliability.
The Future of Urban Mobility What will electrified transportation look like at high penetrations? A few NREL projects offer some perspective. Among the most experimental, NREL is helping the city of Denver develop a smart community, integrated with electrified mobility and featuring automated charging and vehicle dispatch.
On another path to advanced mobility, Los Angeles has embarked on a plan to modernize its electricity system infrastructure, reflecting California EV grid stability goals—aiming for a 100% renewable energy supply by 2045, along with aggressive electrification targets for buildings and vehicles. Through the Los Angeles 100% Renewable Energy Study, the city is currently working with NREL to assess the full-scale impacts of the transition in a detailed analysis that integrates diverse capabilities across the laboratory.
The transition would include the Port of Long Beach, the busiest container port in the United States.
At the port, NREL is applying the same sort of scenario forecasting and controls evaluation as other projects, in order to find the optimal mix of technologies that can be integrated for both grid stability and a reliable quality of service: a mix of hydrogen fuel-cell and battery EVs, battery storage systems, on-site renewable generation, and extreme coordination among everything.
"Hydrogen at ports makes sense for the same reason as trucks: Marine applications have big power and energy demands," Wipke said. "But it's really the synergies between diverse technologies—the existing infrastructure for EVs and the flexibility of bulk battery systems—that will truly make the transition to high renewable energy possible."
Like the Port of Long Beach, transportation hubs across the nation are adapting to a complex environment of new mobility solutions. Airports and public transit stations involve the movement of passengers, goods, and services at a volume exceeding anywhere else. With the transition to digitally connected electric mobility changing how airports plan for the future, NREL projects such as Athena are using the power of high-performance computing to demonstrate how these hubs can maximize the value of passenger and freight mobility per unit of energy, time, and/or cost.
The growth in complexity for transportation hubs has just begun, however. Looking ahead, fleets of ride-sharing EVs, automated vehicles, and automated ride-sharing EV fleets could present the largest effort to manage mobility yet.
A Self-Driving Power Grid To understand the full impact of future mobility-service providers, NREL developed the HIVE (Highly Integrated Vehicle Ecosystem) simulation framework. HIVE combines factors related to serving mobility needs and grid operations—such as a customer's willingness to carpool or delay travel, and potentially time-variable costs of recharging—and simulates the outcome in an integrated environment.
"Our question is, how do you optimize the management of a fleet whose primary purpose is to provide rides and improve that fleet's dispatch and charging?" said Eric Wood, an NREL vehicle systems engineer.
HIVE was developed as part of NREL's Autonomous Energy Systems research to optimize the control of automated vehicle fleets. That is, optimized routing and dispatch of automated electric vehicles.
The project imagines how price signals could influence dispatch algorithms. Consider one customer booking a commute through a ride-hailing app. Out of the fleet of vehicles nearby—variously charged and continually changing locations—which one should pick up the customer?
Now consider the movements of thousands of passengers in a city and thousands of vehicles providing transportation services. Among the number of agents, the moment-to-moment change in energy supply and demand, and the broad diversity in vendor technologies, "we're playing with a lot of parameters," Wood said.
But cutting through all the complexity, and in the midst of massive simulations, the end goal for vehicle-to-grid integration is consistent:
"The motivation for our work is that there are forecasts for significant load on the grid from the electrification of transportation," Wood said. "We want to ensure that this load is safely and effectively integrated, while meeting the expectations and needs of passengers."
The Port of Long Beach uses a mix of hydrogen fuel-cell and battery EVs, battery storage systems, on-site renewable generation, and extreme coordination among everything. Credit: National Renewable Energy Laboratory True Replacement without Caveats
Electric vehicles are not necessarily helpful to the grid, but they can be. As EVs become established in the transportation sector, NREL is studying how to even out any bumps that electrified mobility could cause on the grid and advance any benefits to commuters or industry.
"It all comes down to load flexibility," Meintz said. "We're trying to decide how to optimally dispatch vehicle charging to meet quality-of-service considerations, while also minimizing charging costs."
SDG&E Minimum Bill Proposal would impose a $38.40 fixed charge, discouraging rooftop solar, burdening low income households, and shifting grid costs during peak demand, as the CPUC weighs consumer impacts and affordability.
Key Points
Sets a $38.40 monthly minimum bill that raises low usage costs, deters rooftop solar, and burdens low income households.
✅ $38.40 fixed charge regardless of usage
✅ Disincentivizes rooftop solar investments
✅ Disproportionate impact on low income customers
The utility San Diego Gas & Energy has an aggressive proposal pending before the California Public Utilities Commission, amid recent commission changes in San Diego that highlight how regulatory decisions affect local customers: It wants to charge most residential customers a minimum bill of $38.40 each month, regardless of how much energy they use. The costs of this policy would hit low-income customers and those who generate their own energy with rooftop solar. We’re urging the Commission to oppose this flawed plan—and we need your help.
SDG&E’s proposal is bad news for sustainable energy. About half of the customers whose bills would go up under this proposal have rooftop solar. The policy would deter other customers from investing in rooftop solar by making these investments less economical. Ultimately, lost opportunities for solar would mean burning more gas in polluting power plants.
The proposal is also bad news for people who already have to scrimp on energy costs. Most customers with big homes and billowing air conditioners won't notice if this policy goes into effect, because they use at least $38 worth of electricity a month anyway. But for households that don’t buy much electricity from the company, including those in small apartments without air conditioning, this proposal would raise the bills. Even for customers on special low-income rates, amid electric bill changes statewide, SDG&E wants a minimum bill of $19.20.
Penalizing customers who don’t use much electricity would disproportionately hurt lower-income customers, raising energy equity concerns across the region, who tend to use less energy than their wealthier neighbors. In the region SDG&E serves, the average family in an apartment uses half as much electricity as a single-family residence. Statewide, low-income households are more than four times as likely to be low-usage electricity customers than high-income households. When it gets hot, residential electricity patterns are often driven by air conditioning. The vast majority of SDG&E's customers live in the coastal climate zone, where access to air conditioning is strongly linked to income: Households with incomes over $150,000 are more than twice as likely to have air conditioning than families making less than $35,000, with significant racial disparities in who has AC.
In its attempt to rationalize its request, SDG&E argues that it should charge everyone for infrastructure costs that do not depend on how much energy they use. But the cost of the grid is driven by how much energy SDG&E delivers on hot summer afternoons, when some customers blast their AC and demand for electricity peaks. If more customers relied on their own solar power or conserved energy, the utility would spend less on its grid and help rein in soaring electricity prices over time.
In the long term, reducing incentives to go solar and conserve energy will strain the grid and drive up costs for everyone, especially as lawmakers may overturn income-based charges and reshape rate design. SDG&E's arguments are part of a standard utility playbook for trying to hike income-based fixed charges, and consumer advocates have repeatedly shut them down. As far as we know, no regulators in the country have allowed a utility to charge customers over $38 for the “privilege” of accessing electric service.
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