Solar will make the grid harder to run

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The electric grid wasn't designed for a million solar roofs.

It was designed to work with big power plants, substations and wires leading to every house and business and for the power in those wires to flow from the generation plant to the customer.

But what happens when the customer is the generation plant? And what happens when there are tens of thousands of solar panels out there?

Power then flows both ways, affecting the amount and quality of electricity. As more and more solar panels are installed, the possible headaches for those who run the grid grows.

But the industry is working on it.

"There are tons of researchers working on this stuff," said Molly Sterkel, who oversees the state's solar subsidy program.

Along with the federal Department of Energy, Sterkel's agency, the California Public Utilities Commission brought together dozens of researchers, utility officials and solar company executives to La Jolla.

The goal of the two-day meeting at the Scripps Institution of Oceanography is to figure out how the electric grid can best handle the addition of lots of solar panels.

The PUC is spending $50 million over several years on the research. The Department of Energy is putting $42 million this fiscal year.

With the number of solar installations increasing, the impacts will grow.

More than 77 percent of San Diego Gas & Electric's circuits have solar panels on them.

By 2020, there will be times of the day when some San Diego neighborhoods will produce more power than they use, said Tom Bialek, chief engineer of smart grid for SDG&E.

The problem isn't in the middle of the summer, when the panels are making lots of power and people are using electricity for air conditioning.

It's at times like April, when the sun shines brightly, but the temperature is comfortable, and the solar power can become a big chunk of the power on the grid.

Partly cloudy days are particularly problematic, Bialek said.

For example, he described how a single large installation in the county, a one-megawatt array, fluctuated from making 700 kilowatts to making nothing on a second-by-second basis as clouds passed by.

That caused the voltage on the circuit to which it's connected to fluctuate beyond the standards, as more power had to be brought in to deal with it.

Voltage is a function of how much power is on a system and where it comes from fluctuations can cause malfunctions for customers.

And things will get even more interesting if, as SDG&E predicts, people turn to plug-in cars in larger numbers. Many of those who will drive electric also own rooftop solar panels.

So, what can be done about it?

There's no silver bullet, but researchers are working on a variety of solutions that include better forecasting, energy storage and more information about how the grid works.

Tracking clouds as they move across a city will give the utility a better idea of where and when solar generation will happen. Forecasting customer behavior — like when people plug in their cars — will help.

But information gathered from smart meters and sensors and weather stations around a region will also give a better picture of what's happening on the grid.

And when power production suddenly drops, something has to make up for it. That can include power plants that have turbines already spinning and ready to put juice on the grid, but also storage in capacitors or batteries near customers.

These changes will also affect how much it costs to run the grid and who has to pay for it.

Most solar customers right now put extra power they make during the day on the grid, then draw power at night when the sun is not shining.

In effect, they're using the grid as a giant battery.

Right now, the cost of the wires, cables and substations is included as part of the electricity, the actual energy you use. But if people are making as much electricity as they use — or if they make more — they're not paying for the cost of running the grid.

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European gas prices fall to pre-Ukraine war level

European Gas Prices hit pre-invasion lows as LNG inflows, EU storage gains, and softer oil markets ease the energy crisis, while recession risks, windfall taxes, and ExxonMobil's challenge shape demand and policy.

 

Key Points

European gas prices reflect supply, LNG inflows, storage, and policy, shaping energy costs for households and industry.

✅ Month-ahead hit €76.78/MWh, rebounding to €85.50/MWh.

✅ EU storage 83.2% filled; autumn peak exceeded 95%.

✅ Demand tempered by recession risks; LNG inflows offset Russian cuts.

 

European gas prices have dipped to a level last seen before Russia launched its invasion of Ukraine in February, after warmer weather across the continent eased concerns over shortages and as coal demand dropped across Europe during winter.

The month-ahead European gas future contract dropped as low as €76.78 per megawatt hour on Wednesday, the lowest level in 10 months, amid EU talks on gas price cap strategies that could shape markets, before closing higher at €83.70, according to Refinitiv, a data company.

The invasion roiled global energy markets, serving as a wake-up call to ditch fossil fuels for policymakers, and forced European countries, including industrial powerhouse Germany, to look for alternative suppliers to those funding the Kremlin. Europe had continued to rely on Russian gas even after its 2014 annexation of Crimea and support for separatists in eastern Ukraine.

On Tuesday 83.2% of EU gas storage was filled, data from industry body Gas Infrastructure Europe showed. The EU in May set a target of filling 80% of its gas storage capacity by the start of November to prepare for winter, and weighed emergency electricity measures to curb prices as needed. It hit that target in August, and by mid-November it had peaked at more than 95%.

Gas prices bounced further off the 10-month low on Thursday to reach €85.50 per megawatt hour.

Europe has several months of domestic heating demand ahead, and some industry bosses believe energy shortages could also be a problem next winter, with a worst energy nightmare still possible if supplies tighten. However, traders have also had to weigh the effects of recessions expected in several big European economies, which could dent energy demand.

UK gas prices have also dropped back from their highs earlier this year, and forecasts suggest UK energy bills to drop in April. The day-ahead gas price closed at 155p per therm on Wednesday, compared with 200p/therm at the start of 2022, and more than 500p/therm in August.

Europe’s response to the prospect of gas shortages also included campaigns to reduce energy use – a strategy belatedly adopted by the UK – and windfall taxes on energy companies to help raise revenues for governments, many of which have started expensive subsidies to cushion the impact of high energy prices for households and consumers. Energy companies have enjoyed huge profits at the expense of businesses and households this year, as EU inflation accelerated, but costs remained much the same.

However, the US oil company ExxonMobil on Wednesday launched a legal challenge against EU plans for a windfall tax on oil companies, according to filings by its German and Dutch subsidiaries at the European general court in Luxembourg. ExxonMobil argued that the windfall tax would be “counter-productive” because it said it would result in lower investment in fossil fuel extraction, and that the EU did not have the legal jurisdiction to impose it.

ExxonMobil’s move has prompted anger among European politicians. A message posted on the Twitter account of Paolo Gentiloni, the EU’s commissioner for the economy, on Thursday stated: “Fairness and solidarity, even for corporate giants. #Exxon.”

Oil prices are significantly lower than they were before the start of Russia’s invasion, and only marginally above where they were at the start of 2022. Brent crude oil futures traded at $100 a barrel on 28 February, but were at $81.84 on Thursday.

Oil prices dropped by 1.7% on Thursday. Prices had risen from 12-month lows in early December as traders hoped for increased demand from China after it relaxed its coronavirus restrictions. However, Covid-19 infection numbers are thought to have surged in the country, prompting the US to require travellers from China to show a negative test for the disease and tempering expectations for a rapid increase in oil demand.

 

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Is a Resurgence of Nuclear Energy Possible in Germany?

Germany Nuclear Phase-Out reflects a decisive energy policy shift, retiring reactors as firms shun new builds amid high costs, radioactive waste challenges, climate goals, insurance gaps, and debate over small modular reactors and subsidies.

 

Key Points

Germany's policy to end nuclear plants and block new builds, emphasizing safety, waste, climate goals, and viability.

✅ Driven by safety risks, waste storage limits, and insurance gaps

✅ High capital costs and subsidies make new reactors uneconomic

✅ Political debate persists; SMRs raise cost and proliferation concerns

 

A year has passed since Germany deactivated its last three nuclear power plants, marking a significant shift in its energy policy.

Nuclear fission once heralded as the future of energy in Germany during the 1960s, was initially embraced with minimal concern for the potential risks of nuclear accidents. As Heinz Smital from Greenpeace recalls, the early optimism was partly driven by national interest in nuclear weapon technology rather than energy companies' initiatives.

Jochen Flasbarth, State Secretary in the Ministry of Development, reflects on that era, noting Germany's strong, almost naive, belief in technology. Germany, particularly the Ruhr region, grappled with smog-filled skies at that time due to heavy industrialization and coal-fired power plants. Nuclear energy presented a "clean" alternative at the time.

This sentiment was also prevalent in East Germany, where the first commercial nuclear power plant came online in 1961. In total, 37 nuclear reactors were activated across Germany, reflecting a widespread confidence in nuclear technology.

However, the 1970s saw a shift in attitudes. Environmental activists protested the construction of new power plants, symbolizing a generational rift. The 1979 Three Mile Island incident in the US, followed by the catastrophic Chornobyl disaster in 1986, further eroded public trust in nuclear energy.

The Chornobyl accident, in particular, significantly dampened Germany's nuclear ambitions, according to Smital. Post-Chernobyl, plans for additional nuclear power plants in Germany, once numbering 60, drastically declined.

The emergence of the Green Party in 1980, rooted in anti-nuclear sentiment, and its subsequent rise to political prominence further influenced Germany's energy policy. The Greens, joining forces with the Social Democrats in 1998, initiated a move away from nuclear energy, facing opposition from the Christian Democrats (CDU) and Christian Social Union (CSU).

However, the Fukushima disaster in 2011 prompted a policy reversal from CDU and CSU under Chancellor Angela Merkel, leading to Germany's eventual nuclear phase-out in March 2023, after briefly extending nuclear power amid the energy crisis.

Recently, the CDU and CSU have revised their stance once more, signaling a potential U-turn on the nuclear phaseout, advocating for new nuclear reactors and the reactivation of the last shut-down plants, citing climate protection and rising fossil fuel costs. CDU leader Friedrich Merz has lamented the shutdown as a "black day for Germany." However, these suggestions have garnered little enthusiasm from German energy companies.

Steffi Lemke, the Federal Environment Minister, isn't surprised by the companies' reluctance, noting their longstanding opposition to nuclear power, which she argues would do little to solve the gas issue in Germany, due to its high-risk nature and the long-term challenge of radioactive waste management.

Globally, 412 reactors are operational across 32 countries, even as Europe is losing nuclear power during an energy crunch, with the total number remaining relatively stable over the years. While countries like China, France, and the UK plan new constructions, there's a growing interest in small, modern reactors, which Smital of Greenpeace views with skepticism, noting their potential military applications.

In Germany, the unresolved issue of nuclear waste storage looms large. With temporary storage facilities near power plants proving inadequate for long-term needs, the search for permanent sites faces resistance from local communities and poses financial and logistical challenges.

Environment Minister Lemke underscores the economic impracticality of nuclear energy in Germany, citing prohibitive costs and the necessity of substantial subsidies and insurance exemptions.

As things stand, the resurgence of nuclear power in Germany appears unlikely, with economic factors playing a decisive role in its future.

 

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Idaho gets vast majority of electricity from renewables, almost half from hydropower

Idaho Renewable Energy 2018 saw over 80% in-state utility-scale power from hydropower, wind, solar, biomass, and geothermal, per EIA, with imports declining as Snake River Plain resources and Hells Canyon hydro lead.

 

Key Points

Idaho produced over 80% in-state power from renewables in 2018, led by hydropower, wind, solar, and biomass.

✅ Hydropower supplies about half of capacity; Hells Canyon leads.

✅ Wind provides nearly 20% of capacity along the Snake River Plain.

✅ Utility-scale solar surged since 2016; biomass and geothermal add output.

 

More than 80% of Idaho’s in-state utility-scale electricity generation came from renewable resources in 2018, behind only Vermont, according to recently released data from the U.S. Energy Information Administration’s Electric Power Monthly and broader trends showing that solar and wind reached about 10% of U.S. generation in the first half of 2018.

Idaho generated 17.4 million MWh of electricity in 2018, of which 14.2 million MWh came from renewable sources, while nationally January power generation jumped 9.3% year over year according to EIA. Idaho uses a variety of renewable resources to generate electricity:

Hydroelectricity. Idaho ranked seventh in the U.S. in electricity generation from hydropower in 2018. About half of Idaho’s electricity generating capacity is at hydroelectric power plants, and utility actions such as the Idaho Power settlement could influence future resource choices, and seven of the state’s 10 largest power plants (in terms of electricity generation) are hydroelectric facilities. The largest privately owned hydroelectric generating facility in the U.S. is a three-dam complex on the Snake River in Hells Canyon, the deepest river gorge in North America.

Wind. Nearly one-fifth of Idaho’s electricity generating capacity and one-sixth of its generation comes from wind turbines. Idaho has substantial wind energy potential, and nationally the EIA expects solar and wind to be larger sources this summer, although only a small percentage of the state's land area is well-suited for wind development. All of the state’s wind farms are located in the southern half of the state along the Snake River Plain.

Solar. Almost 5% of Idaho’s electricity generating capacity and 3% of its generation come from utility-scale solar facilities, and nationally over half of new capacity in 2023 will be solar according to projections. The state had no utility-scale solar generation as recently as 2015. Between 2016 and 2017, Idaho’s utility-scale capacity doubled and generation increased from 30,000 MWh to more than 450,000 MWh. Idaho’s small-scale solar capacity also doubled since 2017, generating 33,000 MWh in 2018.

Biomass. Biomass-fueled power plants account for about 2% of the state’s utility-scale electricity generating capacity and 3% of its generation, contributing to a broader U.S. shift where 40% of electricity came from non-fossil sources in 2021. Wood waste from the state’s forests is the primary fuel for these plants.

Geothermal. Idaho is one of seven states with utility-scale geothermal electricity generation. Idaho has one 18-MW geothermal facility, located near the state’s southern border with Utah.

EIA says Idaho requires significant electricity imports, totaling about one-third of demand, to meet its electricity needs. However, Idaho’s electricity imports have decreased over time, and Georgia's recent import levels illustrate how regional dynamics can vary. Almost all of these imports are from neighboring states, as electricity imports from Canada accounted for less than 0.1% of Idaho’s total electricity supply in 2017.

 

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Nuclear helps Belgium increase electricity exports in 2019

Belgium Energy Mix 2019 shows strong nuclear output, rising offshore wind, net electricity exports, and robust interconnections, per Elia, as the nuclear phaseout drives 3.9GW new capacity needs after improved reactor availability.

 

Key Points

High nuclear share, offshore wind, net exports, interconnections; 3.9GW capacity needed amid nuclear phaseout.

✅ Nuclear supplied 48.8% of generation in 2019.

✅ Net exporter: 1.8 TWh, aided by interconnections.

✅ Elia projects 3.9GW new capacity for phaseout.

 

Belgium's electricity transmission system operator, Elia, said that the major trends in 2019 were a steady increase in (mainly offshore) renewable power generation, illustrated by EU wind and solar records across the bloc, better availability of nuclear-generating facilities and an increase in electricity exports.

In 2019, 48.8% of the power generated in Belgium came from nuclear plants. This was in line with the total for 2017 (50%) and significantly more than in 2018 (31.2%) when several reactors were unavailable amid stunted hydro and nuclear output in Europe as well.

Belgium exported more electricity in 2019, as neighbors like Germany saw renewables overtake coal and nuclear generation, with net exports of 1.8TWh (2.1% of the energy mix), in contrast to 2018 when Belgium imported 17.5TWh (20%).

Elia said this “should be viewed in its wider context, of declining nuclear capacity in Europe and regional market shifts, against the backdrop of an increasingly Europeanised market, and can be explained primarily by the good availability of Belgium's generating facilities (especially its nuclear power stations).”

The development of interconnections was also a key factor in the circulation of these electricity flows, as seen with Irish grid price spikes highlighting regional stress, Elia noted.

“Belgium had not been a net exporter of electricity for almost 10 years, the last time being in 2009 and 2010, when total net exports represented 2.8% and 0.2% respectively of Belgium’s energy mix,” it said.

Belgian has seven nuclear reactors – three at Tihange near Liege and four at Doel near Antwerp – and, regionally, nuclear-powered France faces outage risks that influence cross-border reliability.

In 2003, Belgium decided to phase out nuclear power and passed a law to that effect, with neighbors like Germany navigating a balancing act during their energy transition, which was reaffirmed in 2015 and 2018.

A commission appointed to assess the impact of the nuclear phaseout is scheduled to be completed in 2025 but has yet to report any findings.

Elia estimates that some 3.9GW of new power generating capacity will be needed to compensate for Belgium's nuclear phaseout.

 

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Zapping elderly brains with electricity improves short-term memory — for almost an hour

Transcranial electrical stimulation synchronizes brain waves to bolster working memory, aligning neural oscillations across the prefrontal and temporal cortex. This noninvasive brain stimulation may counter cognitive aging by restoring network coupling and improving short-term recall.

 

Key Points

Transcranial electrical stimulation applies scalp currents to synchronize brain waves, briefly enhancing working memory.

✅ Synchronizes prefrontal-temporal networks to restore coupling

✅ Noninvasive tES/tACS protocols show rapid, reversible gains

✅ Effects lasted under an hour; durability remains to be tested

 

To read this sentence, you hold the words in your mind for a few seconds until you reach the period. As you do, neurons in your brain fire in coordinated bursts, generating electrical waves that let you hold information for as long as it is needed, much as novel devices can generate electricity from falling snow under specific conditions. But as we age, these brain waves start to get out of sync, causing short-term memory to falter. A new study finds that jolting specific brain areas with a periodic burst of electricity might reverse the deficit—temporarily, at least.

The work makes “a strong case” for the idea that out-of-sync brain waves in specific regions can drive cognitive aging, says Vincent Clark, a neuroscientist at the University of New Mexico in Albuquerque, who was not involved in the research. He adds that the brain stimulation approach in the study may result in a new electrical therapy for age-related deficits in working memory.

Working memory is “the sketchpad of the mind,” allowing us to hold information in our minds over a period of seconds. This short-term memory is critical to accomplishing everyday tasks such as planning and counting, says Robert Reinhart, a neuroscientist at Boston University who led the study. Scientists think that when we use this type of memory, millions of neurons in different brain areas communicate through coupled bursts of activity, a form of electrical conduction that coordinates timing across networks. “Cells that fire together, wire together,” Reinhart says.

But despite its critical role, working memory is a fragile cognitive resource that declines with age, Reinhart says. Previous studies had suggested that reduced working-memory performance in the elderly is linked to uncoupled activity in different brain areas. So Reinhart and his team set out to test whether recoupling brain waves in older adults could boost the brain’s ability to temporarily store information, a systems-level coordination challenge akin to efforts to use AI for energy savings on modern power grids.

To do so, the researchers used jolts of weak electrical current to synchronize waves in the prefrontal and temporal cortex—two brain areas critical for cognition, a targeted approach not unlike how grids use batteries to stabilize power during strain—and applied the current to the scalps of 42 healthy people in their 60s and 70s who showed no signs of decline in mental ability. Before their brains were zapped, participants looked at a series of images: an everyday object, followed briefly by a blank screen, and then either an identical or a modified version of the same object. The goal was to spot whether the two images were different.

Then the participants took the test again, while their brains were stimulated with a current. After about 25 minutes of applying electricity, participants were on average more accurate at identifying changes in the images than they were before the stimulation. Following stimulation, their performance in the test was indistinguishable from that of a group of 42 people in their 20s. And the waves in the prefrontal and temporal cortex, which had previously been out of sync in most of the participants, started to fire in sync, the researchers report today in Nature Neuroscience, a synchronization imperative reminiscent of safeguards that prevent power blackouts on threatened grids. No such effects occurred in a second group of older people who received jolts of current that didn’t synchronize waves in the prefrontal and temporal cortex.

By using bursts of current to knock brain waves out of sync, the researchers also modulated the brain chatter in healthy people in their 20s, making them slower and less accurate at spotting differences in the image test.

“This is a very nice and clear demonstration of how functional connections underlie memory in younger adults and how alterations … can lead to memory reductions in older adults,” says Cheryl Grady, a cognitive neuroscientist at the Rotman Research Institute at Baycrest in Toronto, Canada. It’s also the first time that transcranial stimulation has been shown to restore working memory in older people, says Michael O’Sullivan, a neuroscientist at the University of Queensland in Brisbane, Australia, though electricity in medicine extends far beyond neurostimulation.

But whether brain zapping could turbocharge the cognitive abilities of seniors or help improve the memories of people with diseases like Alzheimer’s is still unclear: In the study, the positive effects on working memory lasted for just under an hour—though Reinhart says that’s as far as they recorded in the experiment. The team didn’t see the improvements decline toward the end, so he suspects that the cognitive boost may last for longer. Still, researchers say much more work has to be done to better understand how the stimulation works.

Clark is optimistic. “No pill yet developed can produce these sorts of effects safely and reliably,” he says. “Helping people is the ultimate goal of all of our research, and it’s encouraging to see that progress is being made.”

 

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California lawmakers plan to overturn income-based utility charges

California income-based utility charges face bipartisan pushback as the PUC weighs fixed fees for PG&E, SDG&E, and Southern California Edison, reshaping rate design, electricity affordability, energy equity, and privacy amid proposed per-kWh reductions.

 

Key Points

PUC-approved fixed fees tied to household income for PG&E, SDG&E, and SCE, offset by lower per-kWh rates.

✅ Proposed fixed fees: $51 SCE, $73.31 SDG&E, $50.92 PG&E

✅ Critics warn admin, privacy, legal risks and higher bills for savers

✅ Backers say lower-income pay less; kWh rates cut ~33% in PG&E area

 

Efforts are being made across California's political landscape to derail a legislative initiative that introduced income-based utility charges for customers of Southern California Edison and other major utilities.

Legislators from both the Democratic and Republican parties have proposed bills aimed at nullifying the 2022 legislation that established a sliding scale for utility charges based on customer income, a decision made in a late-hour session and subsequently endorsed by Governor Gavin Newsom.

The plan, pending final approval from the state Public Utilities Commission (PUC) — all of whose current members were appointed by Governor Newsom — would enable utilities like Southern California Edison, San Diego Gas & Electric, and PG&E to apply new income-based charges as early as this July.

Among the state legislators pushing back against the income-based charge scheme are Democrats Jacqui Irwin and Marc Berman, along with Republicans Janet Nguyen, Kelly Seyarto, Rosilicie Ochoa Bogh, Scott Wilk, Brian Dahle, Shannon Grove, and Roger Niello.

A cadre of specialists, including economist Ahmad Faruqui who has advised all three utilities implicated in the fee proposal, have outlined several concerns regarding the PUC's pending decision.

Faruqui and his colleagues argue that the proposed charges are excessively high in comparison to national standards, reflecting soaring electricity prices across the state, potentially leading to administrative challenges, legal disputes, and negative unintended outcomes, such as penalizing energy-conservative consumers.

Advocates for the income-based fee model, including The Utility Reform Network (TURN) and the National Resources Defense Council, argue it would result in higher charges for wealthier consumers and reduced fees for those with lower incomes. They also believe that the utilities plan to decrease per kilowatt-hour rates as part of a broader rate structure review to balance out the new fees.

However, even supporters like TURN and the Natural Resources Defense Council acknowledge that the income-based fee model is not a comprehensive solution to making soaring electricity bills more affordable.

If implemented, California would have the highest income-based utility fees in the country, with averages far surpassing the national average of $11.15, as reported by EQ Research:

  • Southern California Edison would charge $51.
  • San Diego Gas & Electric would levy $73.31.
  • PG&E would set fees at $50.92.

The proposal has raised concerns among state legislators about the additional financial burden on Californians already struggling with high electricity costs.

Critics highlight several practical challenges, including the PUC's task of assessing customers' income levels, a process fraught with privacy concerns, potential errors, and constitutional questions regarding access to tax information.

Economists have pointed out further complications, such as the difficulty in accurately assessing incomes for out-of-state property owners and the variability of customers' incomes over time.

The proposed income-based charges would differ by income bracket within the PG&E service area, for example, with lower-income households facing lower fixed charges and higher-income households facing higher charges, alongside a proposed 33% reduction in electricity rates to help mitigate the fixed charge impact.

Yet, the economists warn that most customers, particularly low-usage customers, could end up paying more, essentially rewarding higher consumption and penalizing efficiency.

This legislative approach, they caution, could inadvertently increase costs for moderate users across all income brackets, a sign of major changes to electric bills that could emerge, challenging the very goals it aims to achieve by promoting energy inefficiency.

 

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