Controversial wind farm to build U.S. turbine plant

PG&E Wind Shutdown and Renewable Reliability examines PSPS strategy, wildfire risk, transmission line exposure, wind turbine cut-out speeds, grid stability, and California's energy mix amid historic high-wind events and supply constraints across service areas.

Key Points

An overview of PG&E's PSPS decisions, wildfire mitigation, and how wind cut-out limits influence grid reliability.

✅ Wind turbines reach cut-out near 55 mph, reducing generation.

✅ PSPS mitigates ignition from damaged transmission infrastructure.

✅ Baseload diversity improves resilience during high-wind events.

According to the official, widely reported story, Pacific Gas & Electric (PG&E) initiated power shutoffs across substantial portions of its electric transmission system in northern California as a precautionary measure.

Citing high wind speeds they described as “historic,” the utility claims that if it didn’t turn off the grid, wind-caused damage to its infrastructure could start more wildfires.

Perhaps that’s true. Perhaps. This tale presumes that the folks who designed and maintain PG&E’s transmission system are unaware of or ignored the need to design it to withstand severe weather events, and that the Federal Energy Regulatory Commission (FERC) and North American Electric Reliability Corp. (NERC) allowed the utility to do so.

Ignorance and incompetence happens, to be sure, but there’s much about this story that doesn’t smell right—and it’s disappointing that most journalists and elected officials are apparently accepting it without question.

Take, for example, this statement from a Fox News story about the Kincade Fires: “A PG&E meteorologist said it’s ‘likely that many trees will fall, branches will break,’ which could damage utility infrastructure and start a fire.”

Did you ever notice how utilities cut wide swaths of trees away when transmission lines pass through forests? There’s a reason for that: When trees fall and branches break, the grid can still function, and even as the electric rhythms of New York City shifted during COVID-19, operators planned for variability.

So, if badly designed and poorly maintained infrastructure isn’t the reason PG&E cut power to millions of Californians, what might have prompted them to do so? Could it be that PG&E’s heavy reliance on renewable energy means they don’t have the power to send when a “historic” weather event occurs, especially as policymakers weigh the postponed closure of three power plants elsewhere in California?

Wind Speed Limits

The two most popular forms of renewable energy come with operating limitations, which is why some energy leaders urge us to keep electricity options open when planning the grid. With solar power, the constraint is obvious: the availability of sunlight. One doesn’t generate solar power at night and energy generation drops off with increasing degrees of cloud cover during the day.

The main operating constraint of wind power is, of course, wind speed, and even in markets undergoing 'transformative change' in wind generation, operators adhere to these technical limits. At the low end of the scale, you need about a 6 or 7 miles-per-hour wind to get a turbine moving. This is called the “cut-in speed.” To generate maximum power, about a 30 mph wind is typically required. But, if the wind speed is too high, the wind turbine will shut down. This is called the “cut-out speed,” and it’s about 55 miles per hour for most modern wind turbines.

It may seem odd that wind turbines have a cut-out speed, but there’s a very good reason for it. Each wind turbine rotor is connected to an electric generator housed in the turbine nacelle. The connection is made through a gearbox that is sized to turn the generator at the precise speed required to produce 60 Hertz AC power.

The blades of the wind turbine are airfoils, just like the wings of an airplane. Adjusting the pitch (angle) of the blades allows the rotor to maintain constant speed, which, in turn, allows the generator to maintain the constant speed it needs to safely deliver power to the grid. However, there’s a limit to blade pitch adjustment. When the wind is blowing so hard that pitch adjustment is no longer possible, the turbine shuts down. That’s the cut-out speed.

Now consider how California’s power generation profile has changed. According to Energy Information Administration data, the state generated 74.3 percent of its electricity from traditional sources—fossil fuels and nuclear, amid debates over whether to classify nuclear as renewable—in 2001. Hydroelectric, geothermal, and biomass-generated power accounted for most of the remaining 25.7 percent, with wind and solar providing only 1.98 percent of the total.

By 2018, the state’s renewable portfolio had jumped to 43.8 percent of total generation, with clean power increasing and wind and solar now accounting for 17.9 percent of total generation. That’s a lot of power to depend on from inherently unreliable sources. Thus, it wouldn’t be at all surprising to learn that PG&E didn’t stop delivering power out of fear of starting fires, but because it knew it wouldn’t have power to deliver once high winds shut down all those wind turbines

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California Electricity Rate Overhaul proposes a fixed fee and lower per-kWh rates to boost electrification, renewables, and grid reliability, while CPUC weighs impacts on conservation, low-income customers, and time-of-use pricing across the state.

Key Points

A proposal to add fixed fees and cut per-kWh prices to drive electrification, support renewables, and balance grid costs.

✅ Fixed monthly fee plus lower volumetric per-kWh charges

✅ Aims to accelerate EVs, heat pumps, and building electrification

✅ CPUC review weighs equity, conservation, and grid reliability

California is contemplating a significant overhaul to its electricity rate structure that could bring major changes to electric bills statewide, a move that has ignited debate among environmentalists and politicians alike. The proposed modifications, spearheaded by the California Energy Commission (CEC), would introduce a fixed fee on electric bills and lower the rate per kilowatt-hour (kWh) used.

Motivations for the Change

Proponents of the plan argue that it would incentivize Californians to transition to electric appliances and vehicles, a critical aspect of the state's ambitious climate goals. They reason that a lower per-unit cost would make electricity a more attractive option for applications like home heating and transportation, which are currently dominated by natural gas and gasoline. Additionally, they believe the plan would spur investment in renewable energy sources and distributed generation, ultimately leading to a cleaner electricity grid.

California has some of the most ambitious climate goals in the country, aiming to achieve carbon neutrality by 2045. The transportation sector is the state's largest source of greenhouse gas emissions, and electrification is considered a key strategy for reducing emissions. A 2021 report by the Natural Resources Defense Council (NRDC) found that electrifying all California vehicles and buildings could reduce greenhouse gas emissions by 80% compared to 2020 levels.

Concerns and Potential Impacts

Opponents of the proposal, including some consumer rights groups, express apprehensions that it would discourage conservation efforts. They argue that with a lower per-kWh cost, Californians would have less motivation to reduce their electricity consumption. Additionally, they raise concerns that the income-based fixed charges could disproportionately burden low-income households, who may struggle to afford the base charge regardless of their overall electricity consumption.

A recent study by the CEC suggests that the impact on most Californians would be negligible, even as regulators face calls for action over soaring bills from ratepayers across the state. The report predicts that the average household's electricity bill would change by less than $5 per month under the proposed system. However, some critics argue that this study may not fully account for the potential behavioral changes that could result from the new rate structure.

Similar Initiatives and National Implications

California is not the only state exploring changes to its electricity rates to promote clean energy. Hawaii and New York have also implemented similar programs to encourage consumers to use electricity during off-peak hours. These time-varying rates, also known as time-of-use rates, can help reduce strain on the electricity grid during peak demand periods.

The California proposal has garnered national attention as other states grapple with similar challenges in balancing clean energy goals with affordability concerns amid soaring electricity prices in California and beyond. The outcome of this debate could have significant implications for the broader effort to decarbonize the U.S. power sector.

The Road Ahead

The California Public Utilities Commission (CPUC) is reviewing the proposal and anticipates making a decision later this year, with a potential income-based flat-fee structure under consideration. The CPUC will likely consider the plan's potential benefits and drawbacks, including its impact on greenhouse gas emissions, electricity costs for consumers, and the overall reliability of the grid, even as some lawmakers seek to overturn income-based charges in the legislature.

The decision on California's electricity rates is merely one piece of the puzzle in the fight against climate change. However, it is a significant one, with the potential to shape the state's energy landscape for years to come, including the future of residential rooftop solar markets and investments.

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Space solar power promises wireless energy from orbital solar satellites via microwave or laser power beaming, using photovoltaics and rectennas. NRL and AFRL advances hint at 24-7 renewable power delivery to Earth and airborne drones.

Key Points

Space solar power beams orbital solar energy to Earth via microwaves or lasers, enabling continuous wireless electricity.

✅ Harvests sunlight in orbit and transmits via microwaves or lasers

✅ Provides 24-7 renewable power, independent of weather or night

✅ Enables wireless power for remote sites, grids, and drones

Earlier this year, a small group of spectators gathered in David Taylor Model Basin, the Navy’s cavernous indoor wave pool in Maryland, to watch something they couldn’t see. At each end of the facility there was a 13-foot pole with a small cube perched on top. A powerful infrared laser beam shot out of one of the cubes, striking an array of photovoltaic cells inside the opposite cube. To the naked eye, however, it looked like a whole lot of nothing. The only evidence that anything was happening came from a small coffee maker nearby, which was churning out “laser lattes” using only the power generated by the system as ambitions for cheap abundant electricity gain momentum worldwide.

The laser setup managed to transmit 400 watts of power—enough for several small household appliances—through hundreds of meters of air without moving any mass. The Naval Research Lab, which ran the project, hopes to use the system to send power to drones during flight. But NRL electronics engineer Paul Jaffe has his sights set on an even more ambitious problem: beaming solar power to Earth from space. For decades the idea had been reserved for The Future, but a series of technological breakthroughs and a massive new government research program suggest that faraway day may have finally arrived as interest in space-based solar broadens across industry and government.

Since the idea for space solar power first cropped up in Isaac Asimov’s science fiction in the early 1940s, scientists and engineers have floated dozens of proposals to bring the concept to life, including inflatable solar arrays and robotic self-assembly. But the basic idea is always the same: A giant satellite in orbit harvests energy from the sun and converts it to microwaves or lasers for transmission to Earth, where it is converted into electricity. The sun never sets in space, so a space solar power system could supply renewable power to anywhere on the planet, day or night, as recent tests show we can generate electricity from the night sky as well, rain or shine.

Like fusion energy, space-based solar power seemed doomed to become a technology that was always 30 years away. Technical problems kept cropping up, cost estimates remained stratospheric, and as solar cells became cheaper and more efficient, and storage improved with cheap batteries, the case for space-based solar seemed to be shrinking.

That didn’t stop government research agencies from trying. In 1975, after partnering with the Department of Energy on a series of space solar power feasibility studies, NASA beamed 30 kilowatts of power over a mile using a giant microwave dish. Beamed energy is a crucial aspect of space solar power, but this test remains the most powerful demonstration of the technology to date. “The fact that it’s been almost 45 years since NASA’s demonstration, and it remains the high-water mark, speaks for itself,” Jaffe says. “Space solar wasn’t a national imperative, and so a lot of this technology didn’t meaningfully progress.”

John Mankins, a former physicist at NASA and director of Solar Space Technologies, witnessed how government bureaucracy killed space solar power development firsthand. In the late 1990s, Mankins authored a report for NASA that concluded it was again time to take space solar power seriously and led a project to do design studies on a satellite system. Despite some promising results, the agency ended up abandoning it.

In 2005, Mankins left NASA to work as a consultant, but he couldn’t shake the idea of space solar power. He did some modest space solar power experiments himself and even got a grant from NASA’s Innovative Advanced Concepts program in 2011. The result was SPS-ALPHA, which Mankins called “the first practical solar power satellite.” The idea, says Mankins, was “to build a large solar-powered satellite out of thousands of small pieces.” His modular design brought the cost of hardware down significantly, at least in principle.

Jaffe, who was just starting to work on hardware for space solar power at the Naval Research Lab, got excited about Mankins’ concept. At the time he was developing a “sandwich module” consisting of a small solar panel on one side and a microwave transmitter on the other. His electronic sandwich demonstrated all the elements of an actual space solar power system and, perhaps most important, it was modular. It could work beautifully with something like Mankins' concept, he figured. All they were missing was the financial support to bring the idea from the laboratory into space.

Jaffe invited Mankins to join a small team of researchers entering a Defense Department competition, in which they were planning to pitch a space solar power concept based on SPS-ALPHA. In 2016, the team presented the idea to top Defense officials and ended up winning four out of the seven award categories. Both Jaffe and Mankins described it as a crucial moment for reviving the US government’s interest in space solar power.

They might be right. In October, the Air Force Research Lab announced a $100 million program to develop hardware for a solar power satellite. It’s an important first step toward the first demonstration of space solar power in orbit, and Mankins says it could help solve what he sees as space solar power’s biggest problem: public perception. The technology has always seemed like a pie-in-the-sky idea, and the cost of setting up a solar array on Earth is plummeting, as proposals like a tenfold U.S. solar expansion signal rapid growth; but space solar power has unique benefits, chief among them the availability of solar energy around the clock regardless of the weather or time of day.

It can also provide renewable energy to remote locations, such as forward operating bases for the military, which has deployed its first floating solar array to bolster resilience. And at a time when wildfires have forced the utility PG&E to kill power for thousands of California residents on multiple occasions, having a way to provide renewable energy through the clouds and smoke doesn’t seem like such a bad idea. (Ironically enough, PG&E entered a first-of-its-kind agreement to buy space solar power from a company called Solaren back in 2009; the system was supposed to start operating in 2016 but never came to fruition.)

“If space solar power does work, it is hard to overstate what the geopolitical implications would be,” Jaffe says. “With GPS, we sort of take it for granted that no matter where we are on this planet, we can get precise navigation information. If the same thing could be done for energy, especially as peer-to-peer energy sharing matures, it would be revolutionary.”

Indeed, there seems to be an emerging race to become the first to harness this technology. Earlier this year China announced its intention to become the first country to build a solar power station in space, and for more than a decade Japan has considered the development of a space solar power station to be a national priority. Now that the US military has joined in with a $100 million hardware development program, it may only be a matter of time before there’s a solar farm in the solar system.

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Martha's Vineyard 100% Renewable Energy advances electrification across EVs, heat pumps, distributed solar, offshore wind, microgrids, and battery storage, cutting emissions, boosting efficiency, and strengthening grid resilience for storms and sea-level rise.

Key Points

It is an islandwide plan to electrify transport and buildings using wind, solar, storage, and a modern resilient grid.

✅ Electrify transport: EV adoption and SSA hybrid-electric ferries.

✅ Deploy heat pumps for efficient heating and cooling in buildings.

✅ Modernize the grid: distributed solar, batteries, microgrids, VPP.

Over the past year, it has become increasingly clear that climate change is accelerating. Here in coastal New England, annual temperatures and precipitation have risen more quickly than expected, tidal flooding is now commonplace, and storms have increased in frequency and intensity. The window for avoiding the worst consequences of a climate-changed planet is closing.

At their recent special town meeting, Oak Bluffs citizens voted to approve the 100 per cent renewable Martha’s Vineyard warrant article; now, all six towns have adopted the same goals for fossil fuel reduction and green electricity over the next two decades. Establishing these targets for the adoption of renewable energy, though, is only an initial step. Town and regional master plans for energy transformation are being developed, but this is a whole-community effort as well. Now is the time for action.

There is much to do to combat climate change, but our most important task is to transition our energy system from one heavily dependent on fossil fuels to one that is based on clean electricity. The good news is that this can be accomplished with currently available technology, and can be done in an economically efficient manner.

Electrification not only significantly lowers greenhouse gas emissions, but also is a powerful energy efficiency measure. So even though our detailed Island energy model indicates that eliminating all (or almost all) fossil fuel use will mean our electricity use will more than double, posing challenges for state power grids in some regions, our overall annual energy consumption will be significantly lower.

So what do we specifically need to do?

The primary targets for electrification are transportation (roughly 60 peer cent of current fossil fuel use on Martha’s Vineyard) and building heating and cooling (40 per cent).

Over the past two years, the increase in the number of electric vehicle models available across a wide range of price points has been remarkable — sedans, SUVs, crossovers, pickup trucks, even transit vans. When rebates and tax credits are considered, they are affordable. Range anxiety is being addressed both by increases in vehicle performance and the growing availability of charging locations (other than at home, which will be the predominant place for Islanders to refuel) and, over time, enable vehicle-to-grid support for our local system. An EV purchase should be something everyone should seriously consider when replacing a current fossil vehicle.

The elephant in the transportation sector room is the Steamship Authority. The SSA today uses roughly 10 per cent of the fossil fuel attributable to Martha’s Vineyard, largely but not totally in the ferries. The technology needed for fully electric short-haul vessels has been under development in Scandinavia for a number of years and fully electric ferries are in operation there. A conservative approach for the SSA would be to design new boats to be hybrid diesel-electric, retrofittable to plug-in hybrids to allow for shoreside charging infrastructure to be planned and deployed. Plug-in hybrid propulsion could result in a significant reduction in emissions — perhaps as much as 95 per cent, per the long-range plan for the Washington State ferries. While the SSA has contracted for an alternative fuel study for its next boat, given the long life of the vessels, an electrification master plan is needed soon.

For building heating and cooling, the answer for electrification is heat pumps, both for new construction and retrofits. These devices move heat from outside to inside (in the winter) or inside to outside (summer), and are increasingly integrated into connected home energy systems for smarter control. They are also remarkably efficient (at least three times more efficient than burning oil or propane), and today’s technology allows their operation even in sub-zero outside temperatures. Energy costs for electric heating via heat pumps on the Vineyard are significantly below either oil or propane, and up-front costs are comparable for new construction. For new construction and when replacing an existing system, heat pumps are the smart choice, and air conditioning for the increasingly hot summers comes with the package.

A frequent objection to electrification is that fossil-fueled generation emits greenhouse gases — thus a so-called green grid is required in order to meet our targets. The renewable energy fraction of our grid-supplied electricity is today about 30 per cent; by 2030, under current legislation that fraction will reach 54 per cent, and by 2040, 77 per cent. Proposed legislation will bring us even closer to our 2040 goals. The Vineyard Wind project will strongly contribute to the greening of our electricity supply, and our local solar generation (almost 10 per cent of our overall electricity use at this point) is non-negligible.

A final important facet of our energy system transformation is resilience. We are dependent today on our electricity supply, and this dependence will grow. As we navigate the challenges of climate change, with increasingly more frequent and more serious storms, 2021 electricity lessons underscore that resilience of electricity supply is of paramount importance. In many ways, today’s electricity distribution system is basically the same approach developed by Edison in the late 19th century. In partnership with our electric utility, we need to modernize the grid to achieve our resiliency goals.

While the full scope of this modernization effort is still being developed, the outline is clear. First, we need to increase the amount of energy generated on-Island — to perhaps 25 per cent of our total electricity use. This will be via distributed energy resources (in the form of distributed solar and battery installations as well as community solar projects) and the application of advanced grid control systems. For emergency critical needs, the concept of local microgrids that are detachable from the main grid when that grid suffers an outage are an approach that is technically sound and being deployed elsewhere. Grid coordination of distributed resources by the utility allows for handling of peak power demand; in the early 2030s this could result in what is known as a virtual power plant on the Island.

The adoption of the 100 renewable Martha’s Vineyard warrant articles is an important milestone for our community. While the global and national efforts in the climate crisis may sometimes seem fraught, we can take some considerable pride in what we have accomplished so far and will accomplish in coming years. As with many change efforts, the old catch-phrase applies: think globally, act locally.
 

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India Coal Power PLF rose as capacity utilisation improved on rising peak demand and hydropower shortfall; thermal plants lifted plant load factor, IPPs lagged, and generation beat program targets amid weak rainfall and slower snowmelt.

Key Points

Coal plant load factor in India rose in May on higher demand and weak hydropower, with generation beating targets.

✅ PLF rose to 65.3% as demand climbed

✅ Hydel generation fell 14% YoY on poor rainfall

✅ IPP PLF at 57.8%, below 60% debt comfort

Capacity utilisation levels of coal-based power plants improved in May because of a surge in electricity demand and lower generation from hydroelectric sources. The plant load factor (PLF) of thermal power plants went up to 65.3% in the month, 1.7 percentage points higher than the year-ago period.

While PLFs of central and state government-owned plants were 75.5% and 64.5%, respectively, the same for independent power producers (IPPs) stood at 57.8%, even as coal and electricity shortages eased across the market. Though PLFs of IPPs were higher than May 2017 levels, it failed to cross the 60% mark, which eases debt servicing capabilities of power generation assets.

Thermal power plants generated 96,580 million units (MU) in May, 4% more than the programme set for the month and 5.2% higher than last year, partly supported by higher imported coal volumes in the market. On the other hand, hydel plants produced 10,638 MU, 10% lower than the target, reflecting a 14% decline from last year.

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Peak demand of power on the last day of the month was 1,62,132 MW, 4.3% higher than the demand registered in the same day a year ago, underscoring India's position as the third-largest electricity producer globally.

According to sources, hydropower plants have been generating lesser than expected electricity due to inadequate rainfall and snow melting at a slower pace than previous years, even as the US reported a power generation jump year on year. Data for power generation from renewable sources have not been made available yet.

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Illinois NextGrid redefines utility, customer, and provider roles with grid modernization, DER valuation, upfront rebates, net metering reform, and non-wires alternatives, leveraging rooftop solar, batteries, and performance signals to enhance reliability and efficiency.

Key Points

Illinois NextGrid is an ICC roadmap to value DER and modernize the grid with rebates and non-wires solutions.

✅ Upfront Value-of-DER rebates reward location, time, and performance.

✅ Locational DER reduce peak demand and defer wires and substations.

✅ Encourages non-wires alternatives and data-driven utility planning.

How does the electric utility fit in to a rapidly-evolving energy system? That’s what the Illinois Commerce Commission is trying to determine with its new effort, "NextGrid". Together, we’re rethinking the roles of the utility, the customer, and energy solution providers in a 21st-century digital grid landscape.

In some ways, NextGrid will follow in the footsteps of New York’s innovative Reforming the Energy Vision process, a multi-year effort to re-examine how electric utilities and customers interact. A new approach is essential to accelerating the adoption of clean energy technologies and building a smarter electricity infrastructure in the state.

Like REV, NextGrid is gaining national attention for stakeholder-driven processes to reveal new ways to value distributed energy resources (DER), like rooftop solar and batteries. New York and Illinois’ efforts also seek alternatives, such as virtual power plants, to simply building more and more wires, poles, and power plants to meet the energy needs of tomorrow.

Yet, Illinois is may go a few steps beyond New York, creating a comprehensive framework for utilities to measure how DER are making the grid smarter and more efficient. Here is what we know will happen so far.

On Wednesday, April 5, at the second annual Grid Modernization Forum in Chicago, I’ll be discussing why these provisions could change the future of our energy system, including insights on grid modernization affordability for stakeholders.

Value of distributed energy

The Illinois Commerce Commission’s NextGrid plans grew out of the recently-passed future energy jobs act, a landmark piece of climate and energy policy that was widely heralded as a bipartisan oddity in the age of Trump. The Future Energy Jobs Act will provide significant new investments in renewables and energy efficiency over the next 13 years, redefine the role and value of rooftop solar and batteries on the grid, and lead to significant greenhouse gas emission reductions.

NextGrid will likely start laying the groundwork for valuing distributed energy resources (DER) as envisioned by the Future Energy Jobs Act, which introduces the concept of a new rebate. Illinois currently has a net metering policy, which lets people with solar panels sell their unused solar energy back to the grid to offset their electric bill. Yet the net metering policy had an arbitrary “cap,” or a certain level after which homes and businesses adding solar panels would no longer be able to benefit from net metering.

Although Illinois is still a few years away from meeting that previous “cap,” when it does hit that level, the new policy will ensure additional DER will still be rewarded. Under the new plan, the Value-of-DER rebate will replace net metering on the distribution portion of a customer’s bill (the charge for delivering electricity from the local substation to your house) with an upfront payment, which credits the customer for the value their solar provides to the local grid over the system’s life. Net metering for the energy supply portion of the bill would remain – i.e. homes and businesses would still be able to offset a significant portion of their electric bills by selling excess energy.

What is unique about Illinois’ approach is that the rebate is an upfront payment, rather than on ongoing tariff or reduced net metering compensation, for example. By allowing customers to get paid for the value solar provides to the system at the time it is installed, in the same way new wires, poles, and transformers would, this upfront payment positions DER investments as equally or more beneficial to customers and the electric grid. This is a huge step not only for regulators, but for utilities as well, as they begin to see distributed energy as an asset to the system.

This is a huge step for utilities, as they begin to see distributed energy as an asset to the system.

The rebate would also factor-in the variables of location, time, and performance of DER in the rebate formula, allowing for a more precise calculation of the value to the grid. Peak electricity demand can stress the local grid, causing wear and tear and failure of the equipment that serve our homes and businesses. Power from DER during peak times and in certain areas can alleviate those stresses, therefore providing a greater value than during times of average demand.

In addition, factoring-in the value of performance will take into account the other functions of distributed energy that help keep the lights on. For example, batteries and advanced inverters can provide support for helping avoid voltage fluctuations that can cause outages and other costs to customers.

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