OPG workers receive pay bump

Cold-Climate Heat Pumps deliver efficient heating and cooling for Northern B.C. Net Zero Ready homes, with air-source Mitsubishi H2i systems, triple-pane windows, blower door ACH 0.8, BC Hydro rebates, and CleanBC incentives.

Key Points

Electric air-source systems that heat and cool in subzero climates, cutting emissions and lowering energy costs.

✅ Net Zero Ready, Step Code 5, ACH 0.8 airtightness

✅ Operate efficiently to about -28 C with backup heat

✅ Eligible for BC Hydro and CleanBC rebates

Heat pump provides heating, cooling in northern B.C. home
It's a tradition at Vanderhoof-based Northern Homecraft that, on the day of the blower door test for a just-completed home, everyone who worked on the build gathers to watch it happen. And in the spring of 2021, on a dazzling piece of land overlooking the mouth of the Stuart River near Fort St. James, that day was a cause for celebration.

A new 3,400-square foot home subjected to the blower door test – a diagnostic tool to determine how much air is entering or escaping from a home – was rated as having just .8 air changes per hour (ACH). That helps make it a Net Zero Ready home, and BC Energy Code Step 5 compliant. That means it would take about a third of the amount of energy to heat the home compared to a typical similar-sized home in B.C. today.

From an energy-efficiency perspective, this is a home whose evident beauty is anything but skin deep.

"The home has lot of square footage of finished living space, and it also has a lot of glazing," says Northern Homecraft owner Shay Bulmer, referring to the home's large windows. "We had a lot of window space to deal with, as well as large vaulted open areas where you can only achieve so much additional insulation. There were a few things that the home had going against it as far as performance goes. There were challenges in keeping it comfortable year-round."

Well-insulated home ideal for heat pump option
Most homes in colder areas of B.C. lean on gas-fueled heating systems to deal with the often long, chilly winters. But with the arrival of cold climate heat pumps capable of providing heat efficiently when temperatures dip as low as -30°C, there's now a clean option for those homes, and using more electricity for heat is gaining support in the North as well.

Heat pumps are an increasingly popular option, both for new and existing homes, because they avoid carbon emissions associated with fossil use while also offering summer cooling, even as record-high electricity demand in Yukon underscores the need for efficient systems.

The Fort St. James home, which was built with premium insulation, airtightness and energy efficiency in mind, made the decision to opt for a heat pump even easier. Still, the heat pump option took the home's owners Dexter and Cheryl Hodder by surprise. While their focus was on designing a home that took full advantage of views down to the river, the couple was under the distinct impression that heat pumps couldn't cut it in the chilly north.

"I wasn't really considering a heat pump, which I thought was only a good solution in a moderate climate," says Dexter, who as director of research and education for the John Prince Research Forest, studies wildlife and forestry interactions in north central B.C. "The specs on the heat pump indicate it would work down to -28°C, and I was skeptical of that. But it worked exactly to spec. It almost seems ridiculous to generate heat from outside air at those low temperatures, but it does."

Getting it right with support and rebates
Northern Homecraft took advantage of BC Hydro's Mechanical System Design Pilot program to ensure proper heat pump system design, installation, and verification for the home were applied, and with BC Hydro's first call for power in 15 years driven by electrification, the team prioritized efficient load management.

Based on the home's specific location, size, and performance targets, they installed a ducted Mitsubishi H2I air-source heat pump system. Windows are triple pane, double coated, and a central feature of the home, while insulation specifications were R-40 deep frame insulation in the exterior walls, R-80 insulation in the attic, and R-40 insulation in the vaulted ceilings.

The combination of the year-round benefits of heat pumps, their role in reducing fossil fuel emissions, and the availability of rebates, is making the systems increasingly attractive in B.C., especially as two new BC generating stations were recently commissioned to expand clean supply.

BC Hydro offers home renovation rebates of up to $10,000 for energy-efficient upgrades to existing homes. Rebates are available for windows and doors, insulation, heat pumps, and heat pump hot water heaters. In partnership with CleanBC, rebates of up to $11,000 are also available – when combined with the federal Greener Homes program – for those switching from fossil fuel heating to an electric heat pump.

'Heat dome' pushes summer highs to 40°C
Cooling wasn't really a consideration for Dexter and Cheryl when they were living in a smaller bungalow shaded by trees. But they knew that with the big windows, vaulted ceiling in the living room, and an upstairs bedroom in the new home, there may come a time when they needed air conditioning.

That day arrived shortly after the home was built, as the infamous "heat dome" settled on B.C. and drove temperatures at Fort St. James to a dizzying 40°C.

"It was disgustingly hot, and I don't care if I never see that again here," says Hodder, with a laugh. "But the heat pump maintained the house really nicely throughout, at about 22 degrees. The whole house stayed cool. We just had to close the door to the upper bedroom so it wasn't really heating up during the day."

Hodder says he had to work with the heat pump manufacturer Mitsubishi a couple times over that first year to fix a few issues with the system's controls. But he's confident that the building's tight and well-insulated envelope, and the heat pump's backup electric heat that kicks in when temperatures dip below -28°C, will make it the system-for-all-seasons it was designed to be.

Even with the use of supplemental electric heating during the record chill of December-January, the home's energy costs weren't much higher than the mid-winter energy bills they used to pay in the couple's smaller bungalow that relied on a combination of gas-fired in-floor heating and electric baseboards, as gas-for-electricity swaps are being explored elsewhere.

Fort St. James is a former fur trading post located northwest of Prince George and a short drive north of Vanderhoof. Winters are cold and snowy, with average daily low temperatures in December and January of around -14°C.

"During the summer and into the fall, we were paying well less than $100 a month," says Hodder, looking back at electricity bills over the first year in the home. "And that's everything. We're only electric here, and we also had both of us working from home all last year."

Word of mouth making heat pumps popular in Fort St. James
While the size of the home presented new challenges for the builders, it's one of five Net Zero Ready or Net Zero homes – all equipped with some form of heat pump – that Northern Homecraft has built in Fort St. James, even as debates about going nuclear for electricity continue in B.C.

The smallest of the homes is a two-bedroom, one-bathroom home that's just under 900 square feet. Northern Homecraft may be based in Vanderhoof, but it's the much smaller town of Fort St. James where they're making their mark with super-efficient homes. Net Zero Ready homes are up to 80% more efficient than the standard building code, and become Net Zero once renewable energy generation – usually in the form of photovoltaic solar – is installed, and programs like switching 5,000 homes to geothermal show the broader momentum for clean heating.

"We were pretty proud that the first home we built in Fort St. James was the first single family Net Zero Ready home built in B.C.," says Northern Homecraft's Bulmer. "And I think it's kind of caught on in a smaller community where everyone talks to everyone."

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Sulphur Hexafluoride (SF6) Emissions drive rising greenhouse gas impacts in electrical switchgear, power grids, and renewables, with extreme global warming potential, long atmospheric lifetime, and leakage risks challenging climate targets and grid decarbonization.

Key Points

SF6 emissions are leaks from electrical switchgear and grids, a high-GWP gas with ~1,000-year lifetime.

✅ 23,500x CO2 global warming potential (GWP)

✅ Leaks from switchgear, breakers, gas-insulated substations

✅ Clean air and vacuum alternatives emerging for MV/HV

Sulphur hexafluoride, or SF6, is widely used in the electrical industry to prevent short circuits and accidents.

But leaks of the little-known gas in the UK and the rest of the EU in 2017 were the equivalent of putting an extra 1.3 million cars on the road.

Levels are rising as an unintended consequence of the green energy boom and the broader global energy transition worldwide.

Cheap and non-flammable, SF6 is a colourless, odourless, synthetic gas. It makes a hugely effective insulating material for medium and high-voltage electrical installations.

It is widely used across the industry, from large power stations to wind turbines to electrical sub-stations in towns and cities.

It prevents electrical accidents and fires.

However, the significant downside to using the gas is that it has the highest global warming potential of any known substance. It is 23,500 times more warming than carbon dioxide (CO2).

Just one kilogram of SF6 warms the Earth to the same extent as 24 people flying London to New York return.

It also persists in the atmosphere for a long time, warming the Earth for at least 1,000 years.

So why are we using more of this powerful warming gas?

The way we make electricity around the world is changing rapidly, with New Zealand's push to electrify in its energy system.

Where once large coal-fired power stations brought energy to millions, the drive to combat climate change and to move away from coal means they are now being replaced by mixed sources of power including wind, solar and gas.

This has resulted in many more connections to the electricity grid, and with EU electricity use could double by 2050, a rise in the number of electrical switches and circuit breakers that are needed to prevent serious accidents.

Collectively, these safety devices are called switchgear. The vast majority use SF6 gas to quench arcs and stop short circuits.

"As renewable projects are getting bigger and bigger, we have had to use it within wind turbines specifically," said Costa Pirgousis, an engineer with Scottish Power Renewables on its new East Anglia wind farm, which doesn't use SF6 in turbines.

"As we are putting in more and more turbines, we need more and more switchgear and, as a result, more SF6 is being introduced into big turbines off shore.

"It's been proven for years and we know how it works, and as a result it is very reliable and very low maintenance for us offshore."

How do we know that SF6 is increasing?

Across the entire UK network of power lines and substations, there are around one million kilograms of SF6 installed.

A study from the University of Cardiff found that across all transmission and distribution networks, the amount used was increasing by 30-40 tonnes per year.

This rise was also reflected across Europe with total emissions from the 28 member states in 2017 equivalent to 6.73 million tonnes of CO2. That's the same as the emissions from 1.3 million extra cars on the road for a year.

Researchers at the University of Bristol who monitor concentrations of warming gases in the atmosphere say they have seen significant rises in the last 20 years.

"We make measurements of SF6 in the background atmosphere," said Dr Matt Rigby, reader in atmospheric chemistry at Bristol.

"What we've seen is that the levels have increased substantially, and we've seen almost a doubling of the atmospheric concentration in the last two decades."

How does SF6 get into the atmosphere?

The most important means by which SF6 gets into the atmosphere is from leaks in the electricity industry.

Electrical company Eaton, which manufactures switchgear without SF6, says its research indicates that for the full life-cycle of the product, leaks could be as high as 15% - much higher than many other estimates.

Louis Schaeffer, electrical business manager at Eaton, said: "The newer gear has very low leak rates but the key question is do you have newer gear?

"We looked at all equipment and looked at the average of all those leak rates, and we didn't see people taking into account the filling of the gas. Plus, we looked at how you recycle it and return it and also included the catastrophic leaks."

How damaging to the climate is this gas?

Concentrations in the atmosphere are very small right now, just a fraction of the amount of CO2 in the air.

However, the global installed base of SF6 is expected to grow by 75% by 2030, as data-driven electricity demand surges worldwide.

Another concern is that SF6 is a synthetic gas and isn't absorbed or destroyed naturally. It will all have to be replaced and destroyed to limit the impact on the climate.

Developed countries are expected to report every year to the UN on how much SF6 they use, but developing countries do not face any restrictions on use.

Right now, scientists are detecting concentrations in the atmosphere that are 10 times the amount declared by countries in their reports. Scientists say this is not all coming from countries like India, China and South Korea.

One study found that the methods used to calculate emissions in richer countries "severely under-reported" emissions over the past two decades.

Why hasn't this been banned?

SF6 comes under a group of human-produced substances known as F-gases. The European Commission tried to prohibit a number of these environmentally harmful substances, including gases in refrigeration and air conditioning, back in 2014.

But they faced strong opposition from industries across Europe.

"In the end, the electrical industry lobby was too strong and we had to give in to them," said Dutch Green MEP Bas Eickhout, who was responsible for the attempt to regulate F-gases.

"The electric sector was very strong in arguing that if you want an energy transition, and you have to shift more to electricity, you will need more electric devices. And then you also will need more SF6.

"They used the argument that otherwise the energy transition would be slowed down."

What do regulator and electrical companies say about the gas?

Everyone is trying to reduce their dependence on the gas, and US control efforts suggest targeted policies can drive declines, as it is universally recognised as harmful to the climate.

In the UK, energy regulator Ofgem says it is working with utilities to try to limit leaks of the gas.

"We are using a range of tools to make sure that companies limit their use of SF6, a potent greenhouse gas, where this is in the interest of energy consumers," an Ofgem spokesperson told BBC News.

"This includes funding innovation trials and rewarding companies to research and find alternatives, setting emissions targets, rewarding companies that beat those targets, and penalising those that miss them."

Are there alternatives - and are they very expensive?

The question of alternatives to SF6 has been contentious over recent years.

For high-voltage applications, experts say there are very few solutions that have been rigorously tested.

"There is no real alternative that is proven," said Prof Manu Haddad from the school of engineering at Cardiff University.

"There are some that are being proposed now but to prove their operation over a long period of time is a risk that many companies don't want to take."

Medium voltage operations there are several tried-and-tested materials. Some in the industry say that the conservative nature of the electrical industry is the key reason that few want to change to a less harmful alternative.

"I will tell you, everyone in this industry knows you can do this; there is not a technical reason not to do it," said Louis Schaffer from Eaton.

"It's not really economic; it's more a question that change takes effort and if you don't have to, you won't do it."

Some companies are feeling the winds of change

Sitting in the North Sea some 43km from the Suffolk coast, Scottish Power Renewables has installed one of world's biggest wind farms, in line with a sustainable electric planet vision, where the turbines will be free of SF6 gas.

East Anglia One will see 102 of these towering generators erected, with the capacity to produce up to 714MW (megawatts) of power by 2020, enough to supply half a million homes.

Previously, an installation like this would have used switchgear supplied with SF6, to prevent the electrical accidents that can lead to fires.

Each turbine would normally have contained around 5kg of SF6, which, if it leaked into the atmosphere, would add the equivalent of around 117 tonnes of carbon dioxide. This is roughly the same as the annual emissions from 25 cars.

"In this case we are using a combination of clean air and vacuum technology within the turbine. It allows us to still have a very efficient, reliable, high-voltage network but to also be environmentally friendly," said Costa Pirgousis from Scottish Power Renewables.

"Once there are viable alternatives on the market, there is no reason not to use them. In this case, we've got a viable alternative and that's why we are using it."

But even for companies that are trying to limit the use of SF6, there are still limitations. At the heart of East Anglia One sits a giant offshore substation to which all 102 turbines will connect. It still uses significant quantities of the highly warming gas.

What happens next ?

The EU will review the use of SF6 next year and will examine whether alternatives are available. However, even the most optimistic experts don't think that any ban is likely to be put in place before 2025.

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Nevada Renewable Portfolio Standard 2030 targets 50% clean energy, advancing solar, geothermal, and wind, cutting GHG emissions, phasing out coal, and expanding storage, EV infrastructure, and in-state renewables under PUCN oversight and tax abatements.

Key Points

A state mandate requiring 50% of electricity from renewables by 2030, driving solar, geothermal, wind, and storage.

✅ 50% clean power by 2030; 100% carbon-free target by 2050

✅ Growth in solar, geothermal, wind; coal phase-out; natural gas remains

✅ RETA incentives spur 6.1 GW capacity, jobs, and in-state investment

Nevada is on track to meet its Renewable Portfolio Standard of 50% of electricity generated by renewable energy sources by 2030, according to the Governor's Office of Energy's annual Status of Energy Report.

Based on compliance reports the Public Utilities Commission of Nevada has received, across all providers, about 20% of power is currently generated by renewable resources, and, nationally, renewables ranked second in 2020 as filings show Nevada's investor-owned utility and other power providers have plans to reach the state's ambitious RPS of 50% by 2030, according to the report released Jan. 28.

"Because transportation and electricity generation are Nevada's two largest contributors to greenhouse gas emissions, GOE's program work in 2021 underscored our focus on transportation electrification and reaching the state's legislatively required renewable portfolio standard," GOE Director David Bobzien said in a statement Jan. 28. "While electricity generated from renewable resources currently accounts for about 25% of the state's electricity, a share similar to projections that renewables will soon provide about one-fourth of U.S. electricity overall, we continue to collaborate with the Public Utilities Commission of Nevada, electricity providers, the renewable energy industry and conservation organizations to ensure Nevada reaches our target of 50% clean energy by 2030."

The state's RPS, enacted in 1997 and last modified in 2019, requires an increase in renewable energy, starting with 22% in 2020 and increasing to 50% by 2030. The increase in renewables will reduce GHG emissions and help the state reach its goal of 100% carbon-free power by 2050, while states like Rhode Island have a 100% by 2030 plan, highlighting varying timelines.

Renewable additions
The state added 1.332 GW of renewable capacity in 2021 as part of the Renewable Energy Tax Abatement program, at a time when U.S. renewable energy hit a record 28% in April, for a total renewable capacity of 6.117 GW, according to the report.

The RETA program awards partial sales and use tax and partial property-tax abatements to eligible renewable energy facilities, which increase Nevada's tax revenue and create jobs in a growing industry. Eligible projects must employ at least 50% Nevada workers, pay 175% of Nevada's average wage during construction, and offer health care benefits to workers and their dependents.

Since its adoption in 2010, the GOE has approved 60 projects, including large-scale solar PV, solar thermal, biomass, geothermal and wind projects throughout the state, according to the report. Projects granted abatements in 2021 include:

• 100-MW Citadel Solar Project
• 150-MW Dry Lake Solar + Storage Project
• 714-MW Gemini Solar Project
• 55-MW North Valley Power Geothermal Project
• 113-MW Boulder Flats Solar Project
• 200-MW Arrow Canyon Solar Project

"Nevada does not produce fossil fuels of any significant amount, and gasoline, jet fuel and natural gas for electricity or direct use must be imported," according to the report. "Transitioning to domestically produced renewable resources and electrified transportation can provide cost savings to Nevada residents and businesses, as seen in Idaho's largely renewable mix today, while reducing GHG emissions. About 86% of the fuel for energy that Nevada consumes comes from outside the state."

Phasing out coal plants
Currently, more than two-thirds of the state's electricity is produced by natural gas-fired power plants, with renewables covering most of the remaining generation, according to the report. Nevada continues to phase out its remaining coal power plants, as renewables surpassed coal nationwide in 2022, which provide less than 10% of produced electricity.

"Nevada has seen a significant increase in capturing its abundant renewable energy resources such as solar and geothermal," according to the report. "Renewable energy production continues to grow, powering Nevada homes and business and serves to diversify the state's economy by exporting solar and geothermal to neighboring states, as California neared 100% renewable electricity for the first time. Nevada has more than tripled its renewable energy production since 2011."

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Duration Portfolio Energy Storage aligns layered peak demand with right-sized batteries, enabling peak shaving, gas peaker replacement, and solar-plus-storage synergy while improving grid flexibility, reliability, and T&D deferral through two- to four-hour battery durations.

Key Points

An approach that layers battery durations to match peaks, cut costs, replace peakers, and boost grid reliability.

✅ Layers 2- to 4-hour batteries by peak duration

✅ Enables solar-plus-storage and peak shaving

✅ Cuts T&D upgrades, emissions, and fuel costs

The debate over energy storage replacing gas-fired peakers has raged for years, but a new approach that shifts the terms of the argument could lead to an acceleration of storage deployments.

Rather than looking at peak demand as a single mountainous peak, some analysts now advocate a layered approach that allows energy storage to better match peak needs and complement ongoing efforts to improve solar and wind power across the grid.

"You don’t have to have batteries that run to infinity."

Some developers of solar-plus-storage projects, bolstered by cheap batteries, say they can already compete head-to-head with gas-fired peakers. "I can beat a gas peaker anywhere in the country today with a solar-plus-storage power plant," Tom Buttgenbach, president and CEO of developer 8minutenergy Renewables, recently told S&P Global.

Customers are very busy these days and rebate programs need to fit the speed of their life. Participation should be quick, easy, and accessible anywhere.

Others disagree. Storage is not disruptive for generation, but will be disruptive for transmission and distribution, Kris Zadlo, executive vice president and chief development officer at Invenergy, told the audience at a Bloomberg New Energy Finance conference last spring. Invenergy, like many renewable power developers, develops generation, energy storage and transmission projects.

But there is another path that avoids the pitfalls of positions on either end of the all-or-none approach. "Do the analysis of the need itself," Ray Hohenstein, market applications director at Fluence, told Utility Dive. If the need is only two hours in duration, it may be best served by a two-hour battery. "You don’t have to have batteries that run to infinity."

Storage vs. fossil fuel peakers

Energy storage has several benefits over traditional fossil fuel peaking plants, Hohenstein said. It is instantaneous, it has no emissions and requires no fuel, and has limited infrastructure needs. It can also help the grid absorb higher levels of renewable generation by soaking up excess output, such as solar power at noon, and many planned storage additions will be paired with solar in the next few years. But the one thing energy storage cannot do, he said, is provide limitless energy.

So, instead of looking at replacing an individual peaker, Hohenstein advocated a "duration portfolio" approach that uses energy storage to shave peak load.

If the need is for 150 MW of resources that will never need to run for more than two hours at a time, then a battery is "quite cheap," significantly less than a four or eight-hour battery, said Hohenstein. "If you fill up your peak by duration layer, it could be more cost effective."

NREL research driver

Fluence’s approach is informed by research by Paul Denholm and Robert Margolis at the National Renewable Energy Laboratory (NREL), released last spring.

The NREL researchers looked at the California market where they said 11 GW of fossil fuel capacity is expected to be retired by 2029 because of new once-through-cooling requirements that are taking effect. A lot of that capacity is peaking capacity and, according to NREL’s analysis, a large fraction could be replaced with four-hour energy storage, assuming continued storage cost reductions and growth in solar installations.

The key in NREL’s research was the level of solar power penetration. There is a "synergistic" relationship between solar penetration and storage deployment, the researchers wrote, and other studies suggest wind and solar could meet 80% of U.S. demand as these trends continue.

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Renewables' Impact on US Wholesale Electricity Prices is clear: DOE analysis shows wind and solar, capacity gains, and natural gas lowering rates, shifting daily patterns, and triggering occasional negative pricing in PJM and ERCOT.

Key Points

DOE data show wind and solar lower wholesale prices, reshape price curves, and cause negative pricing in markets.

✅ Natural gas price declines remain the largest driver of cheaper power

✅ Wind and solar shift seasonal and time-of-day price patterns

✅ Negative wholesale prices appear near high wind and solar output

One of the arguments that's consistently been raised against doing anything about climate change is that it will be expensive. On the more extreme end of the spectrum, there have been dire warnings about plunging standards of living due to skyrocketing electricity prices. The plunging cost of renewables like solar cheaper than gas has largely silenced these warnings, but a new report from the Department of Energy suggests that, even earlier, renewables were actually lowering the price of electricity in the United States.

Plunging prices
The report focuses on wholesale electricity prices in the US. Note that these are distinct from the prices consumers actually pay, which includes taxes, fees, payments to support the grid that delivers the electricity, and so on. It's entirely possible for wholesale electricity prices to drop even as consumers end up paying more, and market reforms determine how those changes are passed through. That said, large changes in the wholesale price should ultimately be passed on to consumers to one degree or another.

The Department of Energy analysis focuses on the decade between 2008 and 2017, and it includes an overall analysis of the US market, as well as large individual grids like PJM and ERCOT and, finally, local prices. The decade saw a couple of important trends: low natural gas prices that fostered a rapid expansion of gas-fired generators and the rapid expansion of renewable generation that occurred concurrently with a tremendous drop in price of wind and solar power.

Much of the electricity generated by renewables in this time period would be more expensive than that generated by wind and solar installed today. Not only have prices for the hardware dropped, but the hardware has improved in ways that provide higher capacity factors, meaning that they generate a greater percentage of the maximum capacity. (These changes include things like larger blades on wind turbines and tracking systems for solar panels.) At the same time, operating wind and solar is essentially free once they're installed, so they can always offer a lower price than competing fossil fuel plants.

With those caveats laid out, what does the analysis show? Almost all of the factors influencing the wholesale electricity price considered in this analysis are essentially neutral. Only three factors have pushed the prices higher: the retirement of some plants, the rising price of coal, and prices put on carbon, which only affect some of the regional grids.

In contrast, the drop in the price of natural gas has had a very large effect on the wholesale power price. Depending on the regional grid, it's driven a drop of anywhere from $7 to $53 per megawatt-hour. It's far and away the largest influence on prices over the past decade.

Regional variation and negative prices
But renewables have had an influence as well. That influence has ranged from roughly neutral to a cost reduction of $2.2 per MWh in California, largely driven by solar. While the impact of renewables was relatively minor, it is the second-largest influence after natural gas prices, and the data shows that wind and solar are reducing prices rather than increasing them.

The reports note that renewables are influencing wholesale prices in other ways, however. The growth of wind and solar caused the pattern of seasonal price changes to shift in areas of high wind and solar, as seen with solar reshaping prices in Northern Europe as daylight hours and wind patterns shift with the seasons. Similarly, renewables have a time-of-day effect for similar reasons, helping explain why the grid isn't 100% renewable today, which also influences the daily timing price changes, something that's not an issue with fossil fuel power.

A map showing the areas where wholesale electricity prices have gone negative, with darker colors indicating increased frequency.
Enlarge / A map showing the areas where wholesale electricity prices have gone negative, with darker colors indicating increased frequency.

US DOE
One striking feature of areas where renewable power is prevalent is that there are occasional cases in which an oversupply of renewable energy produces negative electricity prices in the wholesale market. (In the least-surprising statement in the report, it concludes that "negative prices in high-wind and high-solar regions occurred most frequently in hours with high wind and solar output.") In most areas, these negative prices are rare enough that they don't have a significant influence on the wholesale price.

That's not true everywhere, however. Areas on the Great Plains see fairly frequent negative prices, and they're growing in prevalence in areas like California, the Southwest, and the northern areas of New York and New England, while negative prices in France have been observed in similar conditions. In these areas, negative wholesale prices near solar plants have dropped the overall price by 3%. Near wind plants, that figure is 6%.

None of this is meant to indicate that there are no scenarios where expanded renewable energy could eventually cause wholesale prices to rise. At sufficient levels, the need for storage, backup plants, and grid management could potentially offset their low costs, a dynamic sometimes referred to as clean energy's dirty secret by analysts. But it's clear we have not yet reached that point. And if the prices of renewables continue to drop, then that point could potentially recede fast enough not to matter.

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Electric weed-zapping farm robots enable precision agriculture, using autonomous mapping, per-plant targeting, and robotics to reduce pesticides, improve soil health, boost biodiversity, and lower costs with data-driven, selective weeding and seed-planting workflows.

Key Points

Autonomous machines that map fields, electrocute weeds per plant, and plant seeds, cutting pesticides, inputs, and costs.

✅ Precision agriculture: per-plant targeting reduces pesticide use up to 95%.

✅ Autonomous mapping robot surveys 20 hectares per day for weed data.

✅ Electric weeding and seeding improve soil health, biodiversity, and ROI.

On a field in England, three robots have been given a mission: to find and zap weeds with electricity, as advances in digitizing the electrical system continue to modernize power infrastructure, before planting seeds in the cleared soil.

The robots — named Tom, Dick and Harry — were developed by Small Robot Company to rid land of unwanted weeds with minimal use of chemicals and heavy machinery, complementing emerging options like electric tractors that aim to cut on-farm emissions.
The startup has been working on its autonomous weed killers since 2017, and this April launched Tom, its first commercial robot which is now operational on three UK farms. The other robots are still in the prototype stage, undergoing testing.

Small Robot says robot Tom can scan 20 hectares (49 acres) a day, collecting data, with AI-driven analysis guiding Dick, a "crop-care" robot, to zap weeds. Then it's robot Harry's turn to plant seeds in the weed-free soil.

Using the full system, once it is up and running, farmers could reduce costs by 40% and chemical usage by up to 95%, the company says, and integration with virtual power plants could further optimize energy use on electrified farms.

According to the UN Food and Agriculture Organization six million metric tons of pesticides were traded globally in 2018, valued at $38 billion.

"Our system allows farmers to wean their depleted, damaged soils off a diet of chemicals," says Ben Scott-Robinson, Small Robot's co-founder and CEO.

Zapping weeds
Small Robot says it has raised over £7 million ($9.9 million). Scott-Robinson says the company hopes to launch its full system of robots by 2023, which will be offered as a service at a rate of around £400 ($568) per hectare. The monitoring robot is placed at a farm first and the weeding and planting robots delivered only when the data shows they're needed — a setup that ultimately relies on a resilient grid, where research into preventing ransomware attacks is increasingly relevant.

To develop the zapping technology, Small Robot partnered with another UK-based startup, RootWave, while innovations like electricity from snow highlight the breadth of emerging energy tech.

"It creates a current that goes through the roots of the plant through the soil and then back up, which completely destroys the weed," says Scott-Robinson. "We can go to each individual plant that is threatening the crop plants and take it out."

"It's not as fast as it would be if you went out to spray the entire field," he says. "But you have to bear in mind we only have to go into the parts of the field where the weeds are." Plants that are neutral or beneficial to the crops are left untouched.

Small Robot calls this "per plant farming" — a type of precise agriculture where every plant is accounted for and monitored.

A business case
For Kit Franklin, an agricultural engineering lecturer from Harper Adams University, efficiency remains a hurdle, even as utilities use AI to adapt to electricity demands that could support wider on-farm electrification.

"There is no doubt in my mind that the electrical system works," he tells CNN Business. "But you can cover hundreds of hectares a day with a large-scale sprayer ... If we want to go into this really precise weed killing system, we have to realize that there is an output reduction that is very hard to overcome."

But Franklin believes farmers will adopt the technology if they can see a business case.

"There's a realization that farming in an environmentally friendly way is also a way of farming in an efficient way," he says. "Using less inputs, where and when we need them, is going to save us money and it's going to be good for the environment and the perception of farmers."

As well as reducing the use of chemicals, Small Robot wants to improve soil quality and biodiversity.

"If you treat a living environment like an industrial process, then you are ignoring the complexity of it," Scott-Robinson says. "We have to change farming now, otherwise there won't be anything to farm."

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