Ontario to Provide New and Expanded Energy-Efficiency Programs

US SF6 Emissions Decline as NOAA analysis and EPA mitigation show progress, with atmospheric measurements and Greenhouse Gas Reporting verifying reductions from the electric power grid; sulfur hexafluoride's extreme global warming potential underscores inventory improvements.

Key Points

A documented drop in US sulfur hexafluoride emissions, confirmed by NOAA atmospheric data and EPA reporting reforms.

✅ NOAA towers and aircraft show 2007-2018 decline

✅ EPA reporting and utility mitigation narrowed inventory gaps

✅ Winter leaks and servicing signal further reduction options

A new NOAA analysis shows U.S. emissions of the super-potent greenhouse gas sulfur hexafluoride (SF6) have declined between 2007-2018, likely due to successful mitigation efforts by the Environmental Protection Agency (EPA) and the electric power industry, with attention to SF6 in the power industry across global markets. 

At the same time, significant disparities that existed previously between NOAA’s estimates, which are based on atmospheric measurements, and EPA’s estimates, which are based on a combination of reported emissions and industrial activity, have narrowed following the establishment of the EPA's Greenhouse Gas Reporting Program. The findings, published in the journal Atmospheric Chemistry and Physics, also suggest how additional emissions reductions might be achieved. 

SF6 is most commonly used as an electrical insulator in high-voltage equipment that transmits and distributes electricity, and its emissions have been increasing worldwide as electric power systems expand, even as regions hit milestones like California clean energy surpluses in recent years. Smaller amounts of SF6 are used in semiconductor manufacturing and in magnesium production. 

SF6 traps 25,000 times more heat than carbon dioxide over a 100-year time scale for equal amounts of emissions, and while CO2 emissions flatlined in 2019 globally, that comparison underscores the potency of SF6. That means a relatively small amount of the gas can have a significant impact on climate warming. Because of its extremely large global warming potential and long atmospheric lifetime, SF6 emissions will influence Earth’s climate for thousands of years.

In this study, researchers from NOAA’s Global Monitoring Laboratory, as record greenhouse gas concentrations drive demand for better data, working with colleagues at EPA, CIRES, and the University of Maryland, estimated U.S. SF6 emissions for the first time from atmospheric measurements collected at a network of tall towers and aircraft in NOAA’s Global Greenhouse Gas Reference Network. The researchers provided an estimate of SF6 emissions independent from the EPA’s estimate, which is based on reported SF6 emissions for some industrial facilities and on estimated SF6 emissions for others.

“We observed differences between our atmospheric estimates and the EPA’s activity-based estimates,” said study lead author Lei Hu, a Global Monitoring Laboratory researcher who was a CIRES scientist at the time of the study. “But by closely collaborating with the EPA, we were able to identify processes potentially responsible for a significant portion of this difference, highlighting ways to improve emission inventories and suggesting additional emission mitigation opportunities, such as forthcoming EPA carbon capture rules for power plants, in the future.” 

In the 1990s, the EPA launched voluntary partnerships with the electric power, where power-sector carbon emissions are falling as generation shifts, magnesium, and semiconductor industries to reduce SF6 emissions after the United States recognized that its emissions were significant. In 2011, large SF6 -emitting facilities were required to begin tracking and reporting their emissions under the EPA Greenhouse Gas Reporting Program. 

Hu and her colleagues documented a decline of about 60 percent in U.S. SF6 emissions between 2007-2018, amid global declines in coal-fired power in some years—equivalent to a reduction of between 6 and 20 million metric tons of CO2 emissions during that time period—likely due in part to the voluntary emission reduction partnerships and the EPA reporting requirement. A more modest declining trend has also been reported in the EPA’s national inventories submitted annually under the United Nations Framework Convention on Climate Change. 

Examining the differences between the NOAA and EPA independent estimates, the researchers found that the EPA’s past inventory analyses likely underestimated SF6 emissions from electrical power transmission and distribution facilities, and from a single SF6 production plant in Illinois. According to Hu, the research collaboration has likely improved the accuracy of the EPA inventories. The 2023 draft of the EPA’s U.S. Greenhouse Gas Emissions and Sinks: 1990-2021 used the results of this study to support revisions to its estimates of SF6 emissions from electrical transmission and distribution. 

The collaboration may also lead to improvements in the atmosphere-based estimates, helping NOAA identify how to expand or rework its network to better capture emitting industries or areas with significant emissions, according to Steve Montzka, senior scientist at GML and one of the paper’s authors.

Hu and her colleagues also found a seasonal variation in SF6 emissions from the atmosphere-based analysis, with higher emissions in winter than in summer. Industry representatives identified increased servicing of electrical power equipment in the southern states and leakage from aging brittle sealing materials in the equipment in northern states during winter as likely explanations for the enhanced wintertime emissions—findings that suggest opportunities for further emissions reductions.

“This is a great example of the future of greenhouse gas emission tracking, where inventory compilers and atmospheric scientists work together to better understand emissions and shed light on ways to further reduce them,” said Montzka.

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Arc One Electric Speedboat delivers zero-emission performance, quiet operation, and reduced maintenance, leveraging battery propulsion, aerospace engineering, and venture-backed innovation to cut noise pollution, fuel costs, and water contamination in high-performance marine recreation.

Key Points

Arc One Electric Speedboat is a battery-powered, zero-emission craft offering quiet, high-performance marine cruising.

✅ 475 hp, 24 ft hull, about 40 mph top speed

✅ Cuts noise, fumes, and water contamination vs gas boats

✅ Backed by Andreessen Horowitz; ex-SpaceX engineers

A team of former SpaceX rocket engineers have joined the race to build the first commercial electric speedboat.

The Arc Boat company announced it had raised $4.25m (£3m) in seed funding to start work on a 24ft 475-horsepower craft that will cost about $300,000.

The LA-based company, which is backed by venture capital firm Andreessen Horowitz (an early backer of Facebook and Airbnb), said the first model of the Arc One boat would be available for sale by the end of the year.

Mitch Lee, Arc’s chief executive, said he wanted to build electric boats because of the impact conventional petrol- or diesel-powered boats have on the environment.

“They not only get just two miles to the gallon, they also pump a lot of those fumes into the water,” Lee said. “In addition, there is the huge noise pollution factor [of conventional boats] and that is awful for the marine life. With gas-powered boats it’s not just carbon emissions into the air, it’s also polluting the water and causing noise pollution. Electric boats, like electric ships clearing the air on the B.C. coast, eliminate all that.”

Lee said electric vessels would also reduce the hassle of boat ownership. “I love being out on the water, being on a boat is so much fun, but owning a boat is so awful,” he said. “I have always believed that electric boats make sense. They will be quicker, quieter and way cheaper and easier to operate and maintain, with access options like an electric boat club in Seattle lowering barriers for newcomers.”

While the first models will be very expensive, Lee said the cost was mostly in developing the technology and cheaper versions would be available in the future, mirroring advances in electric aviation seen across the industry. “It is very much the Tesla approach – we are starting up market and using that income to finance research and development and work our way down market,” he said.

Lee said the technology could be applied to larger craft, and even ferries could run on electricity in the future, as projects for battery-electric high-speed ferries begin to scale.

“We started in February with no team, no money and no warehouse,” he said. “By December we are going to be selling the Arc One, and we are hiring aggressively because we want to accelerate the adoption of electric boats across a whole range of craft, including an electric-ready ferry on Kootenay Lake.”

Lee founded the company with fellow mechanical engineer Ryan Cook. Cook, the company’s chief technology officer, was previously the lead mechanical engineer at Elon Musk’s space exploration company SpaceX where he worked on the Falcon 9 rocket, the world’s first orbital class reusable rocket. In parallel, Harbour Air's electric aircraft highlights cross-sector electrification. Apart from Lee, all of Arc’s employees have some experience working at SpaceX.

The Arc boat, which would have a top speed of 40 mph, joins a number of startups rushing to make the first large-scale production of electric-powered speedboats, while a Vancouver seaplane airline demonstrates complementary progress with a prototype electric aircraft. The Monaco Yacht Club this month held a competition for electric boat prototypes to “instigate a new vision and promote all positive approaches to bring yachting into line” with global carbon dioxide emission reduction targets. Sweden’s Candela C-7 hydrofoil boat was crowned the fastest electric vessel.

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Twin States Clean Energy Link connects New England to Hydro-Quebec via a 1,200 MW transmission line, DOE-backed capacity, underground segments, existing corridors, boosting renewable energy reliability across Vermont and New Hampshire with cross-border grid flexibility.

Key Points

DOE-backed 1,200 MW line linking Hydro-Quebec to New England, adding clean capacity with underground routes.

✅ 1,200 MW cross-border capacity for the New England grid

✅ Uses existing corridors; underground in VT and northern NH

✅ DOE capacity contract lowers risk and spurs investment

A proposal to build a new transmission line to connect New England with Canadian hydropower is one step closer to reality.

The U.S. Department of Energy announced Monday that it has selected the Twin States Clean Energy Link as one of three transmission projects that will be part of its $1.3 billion cross-border transmission initiative to add capacity to the grid.

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Twin States is a proposal from National Grid, a utility company that serves Massachusetts, New York, and Rhode Island, and also owns transmission in England and Wales as the region advances projects like the Scotland-to-England subsea link that expand renewable flows, and the non-profit Citizens Energy Corporation.

The transmission line would connect New England with power from Hydro-Quebec, moving into the United States from Canada in Northern Vermont and crossing into New Hampshire near Dalton. It would run through parts of Grafton, Merrimack, and Hillsborough counties, routing through a substation in Dunbarton and ending at a proposed new substation in Londonderry. (Here's a map of the Twin States proposal.)

The federal funding will allow the U.S. Department of Energy to purchase capacity on the planned transmission line, which officials say reduces the risk for other investors and can help encourage others to purchase capacity.

The project has gotten support from local officials in Vermont and New Hampshire, but there are still hurdles to cross. The contract negotiation process is beginning, National Grid said, and the proposal still needs approvals from regulators before construction could begin.

First Nations communities in Canada have opposed transmission lines connecting Hydro-Quebec with New England in the past, and the company has faced scrutiny from environmental groups.

What would Twin States look like?
Transmission projects, like the failed Northern Pass proposal, have been controversial in New England, though the Great Northern Transmission Line progressed in Minnesota.

But Reihaneh Irani-Famili, vice president of capital delivery, project management and construction at National Grid, said this one is different because the developers listened to community concerns before planning the project.

“They did not want new corridors of infrastructure, so we made sure that we're using existing right of way,” she said. “They did not want the visual impact and some of the newer corridors of infrastructure, we're making sure we're undergrounding portions of the line.”

In Vermont and northern New Hampshire, the transmission lines would be buried underground along state roads. South of Littleton, they would be located within existing transmission corridors.

The developers say the lines could provide 1,200 megawatts of transmission capacity. The project would have the ability to carry electricity from hydro facilities in Quebec to New England, and would also be able to bring electricity from New England into Quebec, a step toward broader macrogrid connectivity across regions.

“Those hydro dams become giant green batteries for the region, and they hold that water until we need the electrons,” Irani-Famili said. “So if you think about our energy system not as one that sees borders, but one that sees resources, this is connecting the Quebec resources to the New England resources and helping all of us get into that cleaner energy future with a lot less build than we otherwise would have.”

Irani-Famili says the transmission line could help facilitate more clean energy resources like offshore wind coming online. In a report released last week by New Hampshire’s Department of Energy, authors said importing Canadian hydropower could be one of the most cost-effective ways to move away from fossil fuels on the electric grid.

National Grid estimates the project will help save energy customers $8.3 billion in its first 12 years. The developers are constructing a $260 million “community benefits plan” that would take some profits from the transmission line and give that money back to communities that host the transmission lines and environmental justice communities in New England.

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AIDAsol shore power Rostock-Warnemfcnde delivers cold ironing for cruise ships, up to 20 MVA at berths P7 and P8, cutting port emissions during berthing and advancing AIDA's green cruising strategy across European ports.

Key Points

Rostock-Warnemfcnde shore power supplies two cruise ships up to 20 MVA, enabling cold ironing and cutting emissions.

✅ Up to 20 MVA; powers two cruise ships at berths P7 and P8

✅ Enables cold ironing for AIDA fleet to reduce berth emissions

✅ Part of AIDA green cruising with fuel cells and batteries

In a ceremony held in Rostock-Warnemünde yesterday during Germany’s 12th National Maritime Conference, the 2,174-passenger cruise ship AIDAsol inaugurated Europe’s largest shore power plants for ships.

The power plant has been established under a joint agreement between AIDA Cruises, a unit of Carnival Corporation & plc (NYSE/LSE: CCL; NYSE: CUK), the state government of Mecklenburg-Western Pomerania, the city of Rostock and the Port of Rostock.

“With our green cruising strategy, we have been investing in a sustainable cruise market for many years,” said AIDA Cruises President Felix Eichhorn. “The shore power plant in Rostock-Warnemünde is another important step — after the facility in Hamburg — on our way to an emission-neutral cruise that we want to achieve with our fleet. I would like to thank the state government of Mecklenburg-Western Pomerania and all partners involved for the good and trusting cooperation. Together, we are sending out an important signal, not just in Germany, but throughout Europe.”

CAN POWER TWO CRUISE SHIPS AT A TIME
The shore power plant, which was completed in summer 2020, is currently the largest in Europe and aligns with port electrification efforts such as the all-electric berth at London Gateway in the UK. With an output of up to 20 megavolt amperes (MVA), two cruise ships can be supplied with electricity at the same time at berths P7 and P8 in Warnemünde.

In regular passenger operation AIDAsol needs up to 4.5 megawatts per hour (MWh) of electricity.

The use of shore power to supply ships with energy is a decisive step in AIDA Cruises’ plans to reduce local emissions to zero during berthing, complementing recent progress with electric ships on the B.C. coast, as a cruise ship typically stays in port around 40% of its operating time.

As early as 2004, when the order for the construction of AIDAdiva was placed, and for all other ships put into service in subsequent years, the company has considered the use of shore power as an option for environmentally friendly ship operation.

Since 2017, AIDA Cruises has been using Europe’s first shore power plant in Hamburg-Altona, where AIDAsol is in regular operation, while operators like BC Ferries add hybrid ferries to expand low-emission service in Canada. Currently, 10 ships in the AIDA fleet can either use shore power where available or are technically prepared for it.

The aim is to convert all ships built from 2000 onwards, supporting future solutions like offshore charging with wind power.

With AIDA Cruises starting a cruise season from Kiel, Germany, on May 22, AIDAsol will also be the first cruise ship to complete the final tests on a newly built shore power plant there, as innovations such as Berlin’s electric flying ferry highlight the broader shift toward electrified waterways. Construction of that plant is the result of a joint initiative by the state government of Schleswig-Holstein, the city and the port of Kiel and AIDA Cruises. AIDAsol is scheduled to arrive in Kiel on the afternoon of May 13.

As part of its green cruising strategy, AIDA Cruises has been investing in a sustainable cruise operation for many years, paralleling urban shifts toward zero-emission bus fleets in Berlin. Other steps on the path to the zero emission ship of the future are already in preparation. This year, AIDAnova will receive the first fuel cell to be used on an ocean-going cruise ship. In 2022, the largest battery storage system to date in cruise shipping will go into operation on board an AIDA ship, similar to advances in battery-electric ferries in the U.S. In addition, the company is already addressing the question of how renewable fuels can be used on board cruise ships in the future.

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Hinkley Point C delays highlight EDF cost overruns, energy security risks, and wholesale power prices, complicating UK net zero plans, Sizewell C financing, and small modular reactor adoption across the grid.

Key Points

Delays at EDF's 3.2GW Hinkley Point C push operations to 2031, lift costs to £46bn, and risk pricier UK electricity.

✅ First unit may slip to 2031; second unit date unclear.

✅ LSEG sees 6% wholesale price impact in 2029-2032.

✅ Sizewell C replicates design; SMR contracts expected soon.

Vincent de Rivaz, former CEO of EDF, confidently announced in 2016 the commencement of the UK's first nuclear power station since the 1990s, Hinkley Point C. However, despite milestones such as the reactor roof installation, recent developments have belied this optimism. The French state-owned utility EDF recently disclosed further delays and cost overruns for the 3.2 gigawatt plant in Somerset.

These complications at Hinkley Point C, which is expected to power 6 million homes, have sparked new concerns about the UK's energy strategy and its ambition to decarbonize the grid by 2050.

The UK government's plan to achieve net zero by 2050 includes a significant role for nuclear energy, reflecting analyses that net-zero may not be possible without nuclear and aiming to increase capacity from the current 5.88GW to 24GW by mid-century.

Simon Virley, head of energy at KPMG in the UK, stressed the importance of nuclear energy in transitioning to a net zero power system, echoing industry calls for multiple new stations to meet climate goals. He pointed out that failing to build the necessary capacity could lead to increased reliance on gas.

Hinkley Point C is envisioned as the pioneer in a new wave of nuclear plants intended to augment and replace Britain's existing nuclear fleet, jointly managed by EDF and Centrica. Nuclear power contributed about 14 percent of the UK's electricity in 2022, even as Europe is losing nuclear power across the continent. However, with the planned closure of four out of five plants by March 2028 and rising electricity demand, there is concern about potential power price increases.

Rob Gross, director of the UK Energy Research Centre, emphasized the link between energy security and affordability, highlighting the risk of high electricity prices if reliance on expensive gas increases.

The first 1.6GW reactor at Hinkley Point C, initially set for operation in 2027, may now face delays until 2031, even after first reactor installation milestones were reported. The in-service date for the second unit remains uncertain, with project costs possibly reaching £46bn.

LSEG analysts predict that these delays could increase wholesale power prices by up to 6 percent between 2029 and 2032, assuming the second unit becomes operational in 2033.

Martin Young, an analyst at Investec, warned of the price implications of removing a large power station from the supply side.

In response to these delays, EDF is exploring the extension of its four oldest plants. Jerry Haller, EDF’s former decommissioning director, had previously expressed skepticism about extending the life of the advanced gas-cooled reactor fleet, but EDF has since indicated more positive inspection results. The company had already decided to keep the Heysham 1 and Hartlepool plants operational until at least 2026.

Nevertheless, the issues at Hinkley Point C raise doubts about the UK's ability to meet its 2050 nuclear build target of 24GW.

Previous delays at Hinkley were attributed to the COVID-19 pandemic, but EDF now cites engineering problems, similar to those experienced at other European power stations using the same technology.

The next major UK nuclear project, Sizewell C in Suffolk, will replicate Hinkley Point C's design, aligning with the UK's green industrial revolution agenda. EDF and the UK government are currently seeking external investment for the £20bn project.

Compared with Hinkley Point C, Sizewell C's financing model involves exposing billpayers to some risk of cost overruns. This, coupled with EDF's track record, could affect investor confidence.

Additionally, the UK government is supporting the development of small modular reactors, while China's nuclear program continues on a steady track, with contracts expected to be awarded later this year.

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California Renewable Energy Curtailment highlights grid congestion, midday solar peaks, limited battery storage, and market constraints, with WEIM participation and demand response programs proposed to balance supply-demand and reduce wasted solar and wind generation.

Key Points

It is the deliberate reduction of solar and wind output when grid limits or low demand prevent full integration.

✅ Grid congestion restricts transmission capacity

✅ Midday solar peaks exceed demand, causing surplus

✅ Storage, WEIM, and demand response mitigate curtailment

California has long been a leader in renewable energy adoption, achieving a near-100% renewable milestone in recent years, particularly in solar and wind power. However, as the state continues to expand its renewable energy capacity, it faces a growing challenge: the curtailment of excess solar and wind energy. Curtailment refers to the deliberate reduction of power output from renewable sources when the supply exceeds demand or when the grid cannot accommodate the additional electricity.

Increasing Curtailment Trends

Recent data from the U.S. Energy Information Administration (EIA) highlights a concerning upward trend in curtailments in California. In 2024, the state curtailed a total of 3,102 gigawatt-hours (GWh) of electricity generated from solar and wind sources, surpassing the 2023 total of 2,660 GWh. This represents a 32.4% increase from the previous year. Specifically, 2,892 GWh were from solar, and 210 GWh were from wind, marking increases of 31.2% and 51.1%, respectively, compared to the first nine months of 2023.

Causes of Increased Curtailment

Several factors contribute to the rising levels of curtailment:

1. Grid Congestion: California's transmission infrastructure has struggled to keep pace with the rapid growth of renewable energy sources. This congestion limits the ability to transport electricity from generation sites to demand centers, leading to curtailment.
   
   

2. Midday Solar Peaks: Amid California's solar boom, solar energy production typically peaks during the midday when electricity demand is lower. This mismatch between supply and demand results in excess energy that cannot be utilized, necessitating curtailment.
   
   

3. Limited Energy Storage: While battery storage technologies are advancing, California's current storage capacity is insufficient to absorb and store excess renewable energy for later use. This limitation exacerbates curtailment issues.
   
   

4. Regulatory and Market Constraints: Existing market structures and regulatory frameworks may not fully accommodate the rapid influx of renewable energy, leading to inefficiencies and increased curtailment.

Economic and Environmental Implications

Curtailment has significant economic and environmental consequences. For renewable energy producers, curtailed energy represents lost revenue and undermines the economic viability of new projects. Environmentally, curtailment means that clean, renewable energy is wasted, and the grid may rely more heavily on fossil fuels to meet demand, counteracting the benefits of renewable energy adoption.

Mitigation Strategies

To address the rising curtailment levels, California is exploring several strategies aligned with broader decarbonization goals across the U.S.:

• Grid Modernization: Investing in and upgrading transmission infrastructure to alleviate congestion and improve the integration of renewable energy sources.
  
  

• Energy Storage Expansion: Increasing the deployment of battery storage systems to store excess energy during peak production times and release it during periods of high demand.
  
  

• Market Reforms: Participating in the Western Energy Imbalance Market (WEIM), a real-time energy market that allows for the balancing of supply and demand across a broader region, helping to reduce curtailment.
  
  

• Demand Response Programs: Implementing programs that encourage consumers to adjust their energy usage patterns, such as shifting electricity use to times when renewable energy is abundant.

Looking Ahead

As California continues to expand its renewable energy capacity, addressing curtailment will be crucial to ensuring the effectiveness and sustainability of its energy transition. By investing in grid infrastructure, energy storage, and market reforms, the state can reduce curtailment levels and make better use of its renewable energy resources, while managing challenges like wildfire smoke impacts on solar output. These efforts will not only enhance the economic viability of renewable energy projects but also contribute to California's 100% clean energy targets by maximizing the use of clean energy and reducing reliance on fossil fuels.

While California's renewable energy sector faces challenges related to curtailment, proactive measures and strategic investments can mitigate these issues, as scientists continue to improve solar and wind power through innovation, paving the way for a more sustainable and efficient energy future.

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