Reactor contract details on way

Canadian electricity transmission enables grid resilience, long-distance power trade, and decarbonization by integrating renewables, hydroelectric storage, and HVDC links, providing backup during extreme weather and lowering costs to reach net-zero, clean energy targets.

Key Points

An interprovincial high-voltage grid that shares clean power to deliver reliable, low-cost decarbonization.

✅ Enables resilience by sharing power across weather zones

✅ Integrates renewables with hydro storage via HVDC links

✅ Lowers decarbonization costs through interprovincial trade

As the recent disaster in Texas showed, climate change requires electricity utilities to prepare for extreme events. This “global weirding” is leaving Canadian electricity grids increasingly exposed to harsh weather that leads to more intense storms, higher wind speeds, heatwaves and droughts that can threaten the performance of electricity systems.

The electricity sector must adapt to this changing climate while also playing a central role in mitigating climate change. Greenhouse gas emissions can be reduced a number of ways, but the electricity sector is expected to play a central role in decarbonization, including powering a net-zero grid by 2050 across Canada. Zero-emissions electricity can be used to electrify transportation, heating and industry and help achieve emissions reduction in these sectors.

Enhancing long-distance transmission is viewed as a cost-effective way to enable a clean and reliable power grid, and to lower the cost of meeting our climate targets. Now is the time to strengthen transmission links in Canada, with concepts like a western Canadian electricity grid gaining traction.

Insurance for climate extremes
An early lesson from the Texas power outages is that extreme conditions can lead to failures across all forms of power supply. The state lost the capacity to generate electricity from natural gas, coal, nuclear and wind simultaneously. But it also lacked cross-border transmission to other electricity systems that could have bolstered supply.

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Long-distance transmission offers the opportunity to escape the correlative clutch of extreme weather, by accessing energy and spare capacity in areas not beset by the same weather patterns. For example, while Texas was in its deep freeze, relatively balmy conditions in California meant there was a surplus of electricity generation capability in that region — but no means to get it to Texas. Building new transmission lines and connections across broader regions, including projects like a hydropower line to New York that expand access, can act as an insurance policy, providing a back-up for regions hit by the crippling effects of climate change.

A transmission tower crumpled under the weight of ice.
The 1998 Quebec ice storm left 3.5 million Quebecers and a million Ontarians, as well as thousands in in New Brunswick, without power. CP Photo/Robert Galbraith
Transmission is also vulnerable to climate disruptions, such as crippling ice storms that leave wires temporarily inoperable. This may mean using stronger poles when building transmission, or burying major high-voltage transmission links, or deploying superconducting cables to reduce losses.

In any event, more transmission links between regions can improve resilience by co-ordinating supply across larger regions. Well-connected grids that are larger than the areas disrupted by weather systems can be more resilient to climate extremes.

Lowering the cost of clean power
Adding more transmission can also play a role in mitigating climate change. Numerous studies have found that building a larger transmission grid allows for greater shares of renewables onto the grid, ultimately lowering the overall cost of electricity.

In a recent study, two of us looked at the role transmission could play in lowering greenhouse gas emissions in Canada’s electricity sector. We found the cost of reducing greenhouse gas emissions is lower when new or enhanced transmission links can be built between provinces.

Average cost increase to electricity in Canada at different levels of decarbonization, with new transmission (black) and without new transmission (red). New transmission lowers the cost of reducing greenhouse gas emissions. (Authors), Author provided
Much of the value of transmission in these scenarios comes from linking high-quality wind and solar resources with flexible zero-emission generation that can produce electricity on demand. In Canada, our system is dominated by hydroelectricity, but most of this hydro capacity is located in five provinces: British Columbia, Manitoba, Ontario, Québec and Newfoundland and Labrador.

In the west, Alberta and Saskatchewan are great locations for building low-cost wind and solar farms. Enhanced interprovincial transmission would allow Alberta and Saskatchewan to build more variable wind and solar, with the assurance that they could receive backup power from B.C. and Manitoba when the wind isn’t blowing and the sun isn’t shining.

When wind and solar are plentiful, the flow of low cost energy can reverse to allow B.C. and Manitoba the opportunity to better manage their hydro reservoir levels. Provinces can only benefit from trading with each other if we have the infrastructure to make that trade possible.

A recent working paper examined the role that new transmission links could play in decarbonizing the B.C. and Alberta electricity systems. We again found that enabling greater electricity trade between B.C. and Alberta can reduce the cost of deep cuts to greenhouse gas emissions by billions of dollars a year. Although we focused on the value of the Site C project, in the context of B.C.'s clean energy shift, the analysis showed that new transmission would offer benefits of much greater value than a single hydroelectric project.

The value of enabling new transmission links between Alberta and B.C. as greenhouse gas emissions reductions are pursued. (Authors), Author provided
Getting transmission built
With the benefits that enhanced electricity transmission links can provide, one might think new projects would be a slam dunk. But there are barriers to getting projects built.

First, electricity grids in Canada are managed at the provincial level, most often by Crown corporations. Decisions by the Crowns are influenced not simply by economics, but also by political considerations. If a transmission project enables greater imports of electricity to Saskatchewan from Manitoba, it raises a flag about lost economic development opportunity within Saskatchewan. Successful transmission agreements need to ensure a two-way flow of benefits.

Second, transmission can be expensive. On this front, the Canadian government could open up the purse strings to fund new transmission links between provinces. It has already shown a willingness to do so.

Lastly, transmission lines are long linear projects, not unlike pipelines. Siting transmission lines can be contentious, even when they are delivering zero-emissions electricity. Using infrastructure corridors, such as existing railway right of ways or the proposed Canadian Northern Corridor, could help better facilitate co-operation between regions and reduce the risks of siting transmission lines.

If Canada can address these barriers to transmission, we should find ourselves in an advantageous position, where we are more resilient to climate extremes and have achieved a lower-cost, zero-emissions electricity grid.

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Toronto Hydro Scam Warning urges customers to spot phishing emails, fraudulent texts, fake bills, and door-to-door threats demanding bitcoin or prepaid cards, with disconnection threats; report scams to the Canadian Anti-Fraud Centre.

Key Points

Advisory on phishing, fake bills, and payment scams posing as Toronto Hydro, with steps to avoid fraud and report.

✅ Hang up suspicious calls; never pay via bitcoin or prepaid cards.

✅ Do not click links in emails or texts; compare bills and account numbers.

✅ Report fraud to the Canadian Anti-Fraud Centre: 1-888-495-8501.

Toronto Hydro has sent out a notice that criminals posing as Toronto Hydro are sending out fraudulent texts, letters and emails, similar to a recent BC Hydro scam reported in British Columbia.

The warning comes in a tweet, along with suggestions on how to protect yourself from fraud, especially as policy debates like an NDP public hydro plan can generate confusing messages.

According to Toronto Hydro, fraudsters are contacting people by phone, text, email, fake electricity bills, and even travelling door-to-door.

They threaten to disconnect the power unless an immediate payment is made, even though legitimate utilities must follow proper disconnection notices processes. The website states that in some cases, criminals request payment via pre-paid credit card or bitcoin.

It’s written on the website that Toronto Hydro does not accept these methods of payment, and they do not threaten to immediately disconnect power, a reminder that stories about power theft abroad are not a model for local billing.

If you suspect you are being targeted, you should immediately hang up any suspicious phone calls. Don’t click on any links in emails or texts asking you to accept electronic transfers, as scammers may impersonate well-known utilities during high-profile news such as Hydro One profit changes to appear credible.

Avoid sharing any personal information over the phone or in-person, and do not make any payments related to Smart Meter Deposits, as this fee does not exist and rate-setting is overseen by the Ontario Energy Board in Ontario.

And remember to always compare bills to previous ones, including the amount and account number, since major accounting decisions like a BC Hydro deferral report can fuel confusing narratives.

To report fraudulent activity, please contact:
Canadian Anti-Fraud Centre at 1-888-495-8501; quote file number 844396

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Canada Clean Electricity leads decarbonization, slashing power-sector emissions through coal phase-out, renewables like hydro, wind, and solar, and nuclear. Provinces cut carbon intensity, enabling electrification of transport and buildings toward net-zero goals.

Key Points

Canada Clean Electricity is the shift to low-emission power by phasing out coal and scaling renewables and nuclear.

✅ 38% cut in electricity emissions since 2005; 84% fossil-free power.

✅ Provinces lead coal phase-out; carbon intensity plummets.

✅ Enables EVs, heat pumps, and building electrification.

It's our country’s one big climate success so far.

"All across Canada, electricity generation has been getting much cleaner. It's our country’s one big climate success so far,"

To illustrate how quickly electric power is being cleaned up, what's still left to do, and the benefits it brings, I've dug into Canada's latest emissions inventory and created a series of charts below.

The sector that could

Climate pollution by Canadian economic sector, 2005 to 2017My first chart shows how Canada's economic sectors have changed their climate pollution since 2005.

While most sectors have increased their pollution or made little progress in the climate fight, our electricity sector has shined.

As the green line shows, Canadians have eliminated an impressive 38 per cent of the climate pollution from electricity generation in just over a decade.

To put these shifts into context, I've shown Canada's 2020 climate target on the chart as a gray star. This target was set by the Harper government as part of the global Copenhagen Accord. Specifically, Canada pledged to cut our climate pollution 17 per cent below 2005 levels under evolving Canadian climate policy frameworks of the time.

As you can see, the electricity sector is the only one to have done that so far. And it didn’t just hit the target — it cut more than twice as much.

Change in Canada's electricity generation, 2005 to 2017My next chart shows how the electricity mix changed. The big climate pollution cuts came primarily from reductions in coal burning, highlighting the broader implications of decarbonizing Canada's electricity grid for fuel choices.

The decline in coal-fired power was replaced (and then some) by increases in renewable electricity and other zero-emissions sources — hydro, wind, solar and nuclear.

As a result, Canada's overall electricity generation is now 84 per cent fossil free.

Every province making progress

A primary reason why electricity emissions fell so quickly is because every province worked to clean up Canada's electricity together.

Change in Canadian provincial electricity carbon intensity, 2005 to 2017

My next chart illustrates this rare example of Canada-wide climate progress. It shows how quickly the carbon-intensity of electricity generation has declined in different provinces.

(Note: carbon-intensity is the amount of climate pollution emitted per kilowatt-hour of electricity generated: gCO2e/kWh).

Ontario clearly led the way with an amazing 92 per cent reduction in climate pollution per kWh in just twelve years. Most of that came from ending the burning of coal in their power plants. But a big chunk also came from cutting in half the amount of natural gas they burn for electricity.

Manitoba, Quebec and B.C. also made huge improvements.

Even Alberta and Saskatchewan, which were otherwise busy increasing their overall climate pollution, made progress in cleaning up their electricity.

These real-world examples show that rapid and substantial climate progress can happen in Canada when a broad-spectrum of political parties and provinces decide to act.

Most Canadians now have superclean electricity

As a result of this rapid cleanup, most Canadians now have access to superclean energy.

Canadian provincial electricity carbon intensity in 2017

Who has it? And how clean is it?

The biggest climate story here is the superclean electricity generated by the four provinces shown on the left side — Quebec, Manitoba, B.C. and Ontario. Eighty per cent of Canadians live in these provinces and have access to this climate-safe energy source.

Those living in Alberta and Saskatchewan, however, still have fairly dirty electricity — as shown in orange on the right — and options like bridging the electricity gap between Alberta and B.C. could accelerate progress in the West.

A lot more cleanup must happen here before the families and businesses in these provinces have a climate-safe energy supply.

What's left to do?

Canada's electricity sector has two big climate tasks remaining: finishing the cleanup of existing power and generating even more clean energy to replace fossil fuels like the gasoline and natural gas used by vehicles, factories and other buildings.

Finishing the clean up

Climate pollution from Canadian provincial electricity 2005 and 2017

As we saw above, more than a third of the climate pollution from electricity has already been eliminated. That leaves nearly two-thirds still to clean up.

Back in 2005, Canada's total electricity emissions were 125 million tonnes (MtCO2).

Over the next twelve years, emissions fell by more than a third (-46 MtCO2). Ontario did most of the work by cutting 33 MtCO2. Alberta, New Brunswick and Nova Scotia made the next biggest cuts of around 4 MtCO2 each.

Now nearly eighty million tonnes of climate pollution remain.

As you can see, nearly all of that now comes from Alberta and Saskatchewan. As a result, continuing Canada's climate progress in the power sector now requires big cuts in the electricity emissions from these two provinces.

Generating more clean electricity

The second big climate task remaining for Canada's electricity is to generate more clean electricity to replace the fossil fuels burned in other sectors. My next chart lets you see how big a task this is.

Clean electricity generation by Canadian province, 2017

It shows how much climate-safe electricity is currently generated in major provinces. This includes zero-emissions renewables (blue bars) and nuclear power (pale blue).

Quebec tops the list with 191 terawatt-hours (TWh) per year. While impressive, it only accounts for around half of the energy Quebecers use. The other half still comes from climate-damaging fossil fuels and to replace those, Quebec will need to build out more clean energy.

The good news here is that electricity is more efficient for most tasks, so fossil fuels can be replaced with significantly less electric energy. In addition, other efficiency and reduction measures can further reduce the amount of new electricity needed.

Newfoundland and Labrador is in the best situation. They are the only province that already generates more climate-safe electricity than they would need to replace all the fossil fuels they burn. They currently export most of that clean electricity.

At the other extreme are Alberta and Saskatchewan. These provinces currently produce very little climate-safe energy. For example, Alberta's 7 TWh of climate-safe electricity is only enough to cover 1 per cent of the energy used in the province.

All told, Canadians currently burn fossil fuels for three-quarters of the energy we use. To preserve a safe-and-sane climate, most provinces will soon need lots more clean electricity in the race to net-zero to replace the fossil fuels we burn.

How soon will they need it?

According to the most recent report from the International Panel on Climate Change (IPCC), avoiding a full-blown climate crisis will require humanity to cut emissions by 45 per cent over the next decade.

Using electricity to clean up other sectors

Finally, let's look at how electricity can help clean up two of Canada’s other high-emission sectors — transportation and buildings.

Cleaning up transportation

Transportation is now the second biggest climate polluting sector in Canada (after the oil and gas industry). So, it’s a top priority to reduce the amount of gasoline we use.

Canadian provincial electricity carbon intensity in 2017, plus gasoline equivalent

Switching to electric vehicles (EVs) can reduce transportation emissions by a little, or a lot. It depends on how clean the electricity supply is.

To make it easy to compare gasoline to each province's electricity I've added a new grey-striped zone at the top of the carbon-intensity chart.

This new zone shows that burning gasoline in cars and trucks has a carbon-intensity equivalent to more than 1,000 gCO2e/kWh. (If you are interested in the details of this and other data points, see the geeky endnotes.)

The good news is that every province's electricity is now much cleaner than gasoline as a transportation fuel.

In fact, most Canadians have electricity that is at least 95 per cent less climate polluting than gasoline. Electrifying vehicles in these provinces virtually eliminates those transportation emissions.

Even in Alberta, which has the dirtiest electricity, it is 20 per cent cleaner than gasoline. That's a help, for sure. But it also means that Albertans must electrify many more vehicles to achieve the same emissions reductions as regions with cleaner electricity.

In addition to reducing climate pollution, switching transportation to electricity brings other big benefits:

It reduces air pollution in cities — a major health hazard.

It cuts the energy required for transportation by 75 per cent — because electric motors are so much more efficient.

It reduces fuel costs up to 80 per cent — saving tens of thousands of dollars.

And for gasoline-importing provinces, using local electricity keeps billions of fuel dollars inside their provincial economy.

As an extra bonus, it makes it hard for companies to manipulate the price or for outsiders to "turn off the taps.”

Cleaning up buildings

Canada's third biggest source of climate pollution is the buildings sector.

Burning natural gas for heating is the primary cause. So, reducing the amount of fossil gas burned in buildings is another top climate requirement.

Canadian provincial electricity carbon intensity in 2017, plus gasoline and nat gas heating equivalent

Heating with electricity is a common alternative. However, it's not always less climate polluting. It depends on how clean the electricity is.

To compare these two heating sources, look at the lower grey-striped zone I've added to the chart.

It shows that heating with natural gas has a carbon-intensity of 200 to 300 gCO2 per kWh of heat delivered. High-efficiency gas furnaces are at the lower end of this range.

As you can see, for most Canadians, electric heat is now the much cleaner choice — nearly eliminating emissions from buildings. But in Alberta and Saskatchewan, electricity is still too dirty to replace natural gas heat.

The climate benefits of electric heat can be improved further by using the newer high-efficiency air-source heat pump technologies like mini-splits. These can heat using one half to one third of the electricity of standard electric baseboard heaters. That means it is possible to use electricity that is a bit dirtier than natural gas and still deliver cleaner heating. As a bonus, heat pumps can free up a lot of existing electricity supply when used to replace existing electric baseboards.

Electrify everything

You’ve probably heard people say that to fight climate breakdown, we need to “electrify everything.” Of course, the electricity itself needs to be clean and what we’ve seen is that Canada is making important progress on that front. The electricity industry, and the politicians that prodded them, all deserve kudos for slashing emissions at more than twice the rate of any other sector.

We still need to finish the cleanup job, but we also need to turn our sights to the even bigger task ahead: requiring that everything fossil fuelled — every building, every factory, every vehicle — switches to clean Canadian power.

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Britain Electricity Demand During Lockdown is around 10 percent lower, as industrial consumers scale back. National Grid reports later morning peaks and continues balancing system frequency and voltage to maintain grid stability.

Key Points

Measured drop in UK power use, later morning peaks, and grid actions to keep frequency and voltage within safe limits.

✅ Daily demand about 10 percent lower since lockdown.

✅ Morning peak down nearly 18 percent and occurs later.

✅ National Grid balances frequency and voltage using flexible resources.

Daily electricity demand in Britain is around 10% lower than before the country went into lockdown last week due to the coronavirus outbreak, data from grid operator National Grid showed on Tuesday.

The fall is largely due to big industrial consumers using less power across sectors, the operator said.

Last week, Prime Minister Boris Johnson ordered Britons to stay at home to halt the spread of the virus, imposing curbs on everyday life without precedent in peacetime.

Morning peak demand has fallen by nearly 18% compared to before the lockdown was introduced and the normal morning peak is later than usual because the times people are getting up are later and more spread out with fewer travelling to work and school, a pattern also seen in Ottawa during closures, National Grid said.

Even though less power is needed overall, the operator still has to manage lower demand for electricity, as well as peaks, amid occasional short supply warnings from National Grid, and keep the frequency and voltage of the system at safe levels.

Last August, a blackout cut power to one million customers and caused transport chaos as almost simultaneous loss of output from two generators caused by a lightning strike caused the frequency of the system to drop below normal levels, highlighting concerns after the emergency energy plan stalled.

National Grid said it can use a number of tools to manage the frequency, such as working with flexible generators to reduce output or draw on storage providers to increase demand, and market conditions mean peak power prices have spiked at times.

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Hydro-Quebec back-billing arises from analogue meter errors and estimated consumption, leading to arrears for electricity usage; disputes over access, payment plans, and potential power diversion reviews can impact cottage owners near Gatineau.

Key Points

Hydro-Quebec back-billing recovers underbilled electricity from analogue meter errors or prolonged estimated use.

✅ Triggered by inaccurate analogue meters or missed readings

✅ Based on actual usage versus prior estimated consumption

✅ Payment plans may spread arrears; theft checks may adjust

A relaxing lakefront cottage has become a powerful source of stress for an Ottawa woman who Hydro-Quebec is charging $5,300 to cover what it says are years of undercharging for electricity usage.

The utility said an old analogue power meter is to blame for years of inaccurate electricity bills for the summer getaway near Gatineau, Que.

Separate from individual billing issues, Hydro-Quebec has also reported pandemic-related losses earlier this year.

Owner Jan Hodgins does not think she should be held responsible for the mistake, nor does she understand how her usage could have surged over the years.

“I’m very hydro conscious, because I was raised that way. When you left a room, you always turned the light out,” she told CTV Montreal on Wednesday, relating her shock after receiving some hefty bills from Hydro-Quebec on Sept. 22.

Hodgins said she mainly uses the cottage on weekends, does not heat the place when she is not there, and does not use a washer or dryer, to keep her energy footprint as small as possible. She’s owned the cottage for 14 years, during which she says her monthly bill has hovered around $40.

Hydro-Quebec said it has not had an accurate reading of her usage for several years, relying instead on consumption estimates to determine what she pays. The company recently reviewed her energy consumption back to 2014, and found their estimates were not accurate.

“In the past, she was consuming about 10 to 15 kilowatt hours per day. This summer she was more around 40 kilowatt hours per day,” Marc-Antoine Pouliot with Hydro-Quebec told CTV Ottawa.

Hodgins said that means her regular bill will now be more than twice the $200 her neighbours are paying for hydro each month, even with peak hydro rates in place.

Hydro-Quebec said it will correct the bill if its technicians discover that someone is illegally diverting power nearby.

Hodgins said it’s not her fault that technicians did not check her meter in person, and chose to rely on inaccurate estimates. Pouliot argues that reaching her cottage was too difficult.

“There was too much snow. There were conditions during the winter disconnection ban period, and the consequence was that people, our workers, were not able to reach the meter,” he said.

Hydro-Quebec said it is willing to stretch out the debt into monthly payments over a year, which Hodgins said amount to $440 per month on top of her regular bill.

Utilities also caution customers about scammers threatening shutoffs during billing disputes.

“I’m on a fixed income. I don’t have that kind of money. I’m completely distraught,” she said. “I don’t know what I’m going to do.”

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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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