Judge rejects challenge to energy mandate

Taltson Hydro Electric Heating directs surplus hydro power in the South Slave to space heat via discounted rates, displacing diesel and cutting greenhouse gas emissions, with rebates, separate metering, and backup systems shaping adoption.

Key Points

An initiative using Taltson's surplus hydro to heat buildings, discount rates replace diesel and cut emissions.

✅ 6.3 cents/kWh heating rate needs separate metering, backup heat

✅ 4-6 MW surplus hydro; outages require diesel; rebates available

✅ Program may be curtailed if new mines or mills demand power

A Northwest Territories green energy advocate says there's an obvious way to expand demand for electricity in the territory's South Slave region without relying on new mining developments — direct it toward heating.

One of the reasons the N.W.T. has always had some of the highest electricity rates in Canada is that a small number of people have to shoulder the huge costs of hydro facilities and power plants.

But some observers point out that residents consume as much energy for heat as they do for conventional uses of electricity, such as lighting and powering appliances. Right now almost all of that heat is generated by expensive oil imported from the United States.

The Northwest Territories Power Corporation says the 18-megawatt Taltson hydro system that serves the South Slave typically has four to six megawatts of excess generating capacity, even as record demand in Yukon is reported. It says using some of that to generate heat is a government priority.

But renewable energy advocate and former N.W.T. MP Dennis Bevington, who lives in the South Slave and heats his home using electricity, says the government is not making it easy for people to tap into that surplus to heat their homes and businesses, a debate that some say would benefit from independent planning at the national level.

Discount rate for heating, but there are catches
The power corporation offers hydro electricity from Taltson to use for heating at a much lower price than it charges for electricity generally. The discounted rate is not available to residential customers.

According to the corporation, consumers pay only 6.3 cents per kilowatt hour compared to the regular rate of just under 24 cents, while Manitoba Hydro financial pressures highlight the risks of expanding demand without new generation.

But to distinguish between the two, users are required to cover the cost of installing a separate power meter. Bevington, who developed the N.W.T.'s first energy strategy, says that is an unnecessary expense.

Taltson expansion key to reducing N.W.T.'s greenhouse gas emissions, says gov't
"The billing is how you control that," he said. "You establish an average electrical use in the winter months. That could be the base rate. Then, if you use power in the winter months above that, you get the discount."

Users are also required to have a back-up heating system. Taltson hydro power offers heating on the understanding that when the hydro system is down — such as during power outages or annual summer maintenance of the hydro system — electricity is not available for heating.
The president and CEO of the power corporation says there's a good reason for that. "The diesels are more expensive to run and they're actually greenhouse gas emitting," said Noel Voykin. "The whole idea of this [electric heat] program is to provide clean energy that is not otherwise being used."

According to the corporation, there have been huge savings for the few who have tapped into the hydro system to heat their buildings, and across Canada utilities are exploring novel generation such as NB Power's Belledune seawater project to diversify supply.

It's being used to heat Aurora College's Breynat Hall, and Joseph B. Tyrrell Elementary School and the transportation department garage in Fort Smith, N.W.T. Electricity is also used to heat the Jackfish power plant in the North Slave region.

The corporation says that during a four-year period, this saved more than 600,000 litres of diesel fuel and reduced greenhouse gas emissions by about 1,700 tonnes.

Bevington says the most obvious place to expand the use of electrical heat is to government housing.

"We have a hundred public housing units in Fort Smith," he said. "The government is putting diesel into those units [for heating] and they could be putting in their own electricity."

Heating a tiny part of energy market
The corporation says it sells only about 2.5 megawatts of electricity for heating each year, which is less than four per cent of the power it sells in the region. It says with some upgrades, another two megawatts of electricity could be made available for electrical heat.

Bevington says the corporation could do more to market electricity for heating. Voykin said that's the government's job. There are three programs that offer rebates to residents and businesses converting to electric heating.

If you build it, will they come? N.W.T. gov't hopes hydro expansion will attract investment
There are better options than billion dollar Taltson expansion, say energy leaders
There may be a reason why the government and the corporation are not more aggressively promoting using surplus electricity in the Taltson system for heating, as large hydro ambitions have reopened old wounds in places like Quebec and Newfoundland and Labrador during recent debates.

It is anticipating that new industrial customers may require that excess capacity in the coming years, and experiences elsewhere show that accommodating new energy-intensive customers can be challenging for utilities. Voykin said those potential new customers include a proposed mine at Pine Point and a pellet mill in Enterprise, N.W.T., even as biomass use faces environmental pushback in some regions.

The corporation says any surplus power in the system will be sold at standard rates to any new industrial customers instead of at discount rates for heating. If that requires cutting back on the heating program, it will be cut back.

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Labrador Island Link Reliability faces scrutiny as Nalcor Energy and General Electric address software issues; Liberty Consulting warns of Holyrood risks, winter outages, grid stability concerns, and PUB oversight for Newfoundland and Labrador.

Key Points

It is the expected dependability of the link this winter, currently uncertain due to GE software and Holyrood risks.

✅ GE software delays may hinder reliable in-service by mid-November.

✅ Holyrood performance issues increase winter outage risk.

✅ PUB directs Hydro to plan contingencies and improve assets.

An independent consultant is questioning if the brand new Labrador Island link can be counted on to supply power to Newfoundland this coming winter.

In June, Nalcor Energy confirmed it had successfully sent power from Churchill Falls to the Avalon Peninsula through its more than 1500-kilometre link, but now the Liberty Consulting Group says it doesn't expect the link will be up and running consistently this winter.

"What we have learned supports a conclusion that the Labrador Island Link is unlikely to be reliably in commercial operation at the start of the winter," says the report dated Aug. 30, 2018.

The link relies on software provided by General Electric but Liberty says there are lingering questions about GE's ability to ensure the necessary software will be in place this fall.

"At an August meeting, company representatives did not express confidence in GE's ability to meet an in-service date for the Labrador Island Link of mid-November," says the report.

Liberty also says testing the link for a brief period this spring and fall doesn't demonstrate long-term reliability.

"The link will remain prone to the uncertainties any new major facility faces early in its operating life, especially one involving technology new to the operating company," according to the report.

Holyrood trouble

The report goes on to say island residents should also be worried about the reliability of the troubled Holyrood facility — a facility that's important when demand for energy is high during winter months.

Liberty says "poor performance at the Holyrood thermal generating station increases the risk of outages considerably."

The group's report concludes the deteriorating condition of Holyrood is a major threat to the island's power supply and Liberty says that threat "could produce very severe consequences when the Labrador Island Link is unavailable."

The consultant says questions about the Labrador Island Link's readiness combined with concerns about the reliability of Holyrood may mean power outages, and for vulnerable customers, debates over hydro disconnections policies often intensify during winter.

"This all suggests that, for at least part of this winter, the island interconnected system may be at the mercy of the weather, where severe events can test utilities' storm response efforts further."

The consultant's report also includes five recommendations to the PUB, reflecting the kind of focused nuclear alert investigation follow-up seen elsewhere.

In essence, Liberty is calling for the board to direct Newfoundland and Labrador Hydro to make plans for the possibility that the link won't be available this winter. It's also calling on hydro to do more to improve the reliability of its other assets, such as Holyrood, as some operators have even contemplated locking down key staff to maintain operations during crises.

Response to Liberty's report

Nalcor CEO Stan Marshall defended the Crown corporation's winter preparedness in an email statement to CBC.

"The right level of planning and investment has been made for our existing equipment so we can continue to meet all of our customer electricity needs for this coming winter season," he wrote.

Regarding the Labrador Island Link, Marshall called for patience.

"This is new technology for our province and integrating the new transmission assets into our current electricity system is complex work that takes time," he said.

There is also a more detailed response from Newfoundland and Labrador Hydro which was sent to the province's Public Utiltiies Board.

Hydro says it will keep testing the Labrador Island Link and increasing the megawatts that are wheeled through it. It also says in October it will begin to give the PUB regular reports on the link's anticipated in-service date.

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New Zealand Renewable Energy Strategy examines decarbonisation, GHG emissions, and net energy as electrification accelerates, expanding hydro, geothermal, wind, and solar PV while weighing intermittency, storage, materials, and energy security for a resilient power system.

Key Points

A plan to expand electricity generation, balancing decarbonisation, net energy limits, and energy security.

✅ Distinguishes decarbonisation targets from renewable capacity growth

✅ Highlights net energy limits, intermittency, and storage needs

✅ Addresses materials, GHG build-out costs, and energy security

The Electricity Authority has released a document outlining a plan to achieve the Government’s goal of more than doubling the amount of electricity generated in New Zealand over the next few decades.

This goal is seen as a way of both reducing our greenhouse gas (GHG) emissions overall, as everything becomes electrified, and ensuring we have a 100 percent renewable energy system at our disposal. Often these two goals are seen as being the same – to decarbonise we must transition to more renewable energy to power our society.

But they are quite different goals and should be clearly differentiated. GHG emissions could be controlled very effectively by rationing the use of a fossil fuel lockdown approach, with declining rations being available over a few years. Such a direct method of controlling emissions would ensure we do our bit to remain within a safe carbon budget.

If we took this dramatic step we could stop fretting about how to reduce emissions (that would be guaranteed by the rationing), and instead focus on how to adapt our lives to the absence of fossil fuels.

Again, these may seem like the same task, but they are not. Decarbonising is generally thought of in terms of replacing fossil fuels with some other energy source, signalling that a green recovery must address more than just wind capacity. Adapting our lives to the absence of fossil fuels pushes us to ask more fundamental questions about how much energy we actually need, what we need energy for, and the impact of that energy on our environment.

MBIE data indicate that between 1990 and 2020, New Zealand almost doubled the total amount of energy it produced from renewable energy sources - hydro, geothermal and some solar PV and wind turbines.

Over this same time period our GHG emissions increased by about 25 percent. The increase in renewables didn’t result in less GHG emissions because we increased our total energy use by almost 50 percent, mostly by using fossil fuels. The largest fossil fuel increases were used in transport, agriculture, forestry and fisheries (approximately 60 percent increases for each).

These data clearly demonstrate that increasing renewable energy sources do not necessarily result in reduced GHG emissions.

The same MBIE data indicate that over this same time period, the amount of Losses and Own Use category for energy use more than doubled. As of 2020 almost 30 percent of all energy consumed in New Zealand fell into this category.

These data indicate that more renewable energy sources are historically associated with less energy actually being available to do work in society.

While the category Losses and Own Use is not a net energy analysis, the large increase in this category makes the call for a system-wide net energy analysis all the more urgent.

Net energy is the amount of energy available after the energy inputs to produce and deliver the energy is subtracted. There is considerable data available indicating that solar PV and wind turbines have a much lower net energy surplus than fossil fuels.

And there is further evidence that when the intermittency and storage requirements are engineered into a total renewable energy system, the net energy of the entire system declines sharply. Could the Losses and Other Uses increase over this 30-year period be an indication of things to come?

Despite the importance of net energy analysis in designing a national energy system which is intended to provide energy security and resilience, there is not a single mention of net energy surplus in the EA reference document.

So over the last 30 years, New Zealand has doubled its renewable energy capacity, and at the same time increased its GHG emissions and reduced the overall efficiency of the national energy system.

And we are now planning to more than double our renewable energy system yet again over the next 30 years, even as zero-emissions electricity by 2035 is being debated elsewhere. We need to ask if this is a good idea.

How can we expand New Zealand’s solar PV and wind turbines without using fossil fuels? We can’t.

How could we expand our solar PV and wind turbines without mining rare minerals and the hidden costs of clean energy they entail, further contributing to ecological destruction and often increasing social injustices? We can't.

Even if we could construct, deliver, install and maintain solar PV and wind turbines without generating more GHG emissions and destroying ecosystems and poor communities, this “renewable” infrastructure would have to be replaced in a few decades. But there are at least two major problems with this assumed scenario.

The rare earth minerals required for this replacement will already be exhausted by the initial build out. Recycling will only provide a limited amount of replacements.

The other challenge is that a mostly “renewable” energy system will likely have a considerably lower net energy surplus. So where, in 2060, will the energy come from to either mine or recycle the raw materials, and to rebuild, reinstall and maintain the next iteration of a renewable energy system?

There is currently no plan for this replacement. It is a serious misnomer to call these energy technologies “renewable”. They are not as they rely on considerable raw material inputs and fossil energy for their production and never ending replacement.

New Zealand is, of course, blessed with an unusually high level of hydro electric and geothermal power. New Zealand currently uses over 170 GJ of total energy per capita, 40 percent of which is “renewable”. This provides approximately 70 GJ of “renewable” energy per capita with our current population.

This is the average global per capita energy level from all sources across all nations, as calls for 100% renewable energy globally emphasize. Several nations operate with roughly this amount of total energy per capita that New Zealand can generate just from “renewables”.

It is worth reflecting on the 170 GJ of total energy use we currently consume. Different studies give very different results regarding what levels are necessary for a good life.

For a complex industrial society such as ours, 100 GJ pc is said to be necessary for a high levels of wellbeing, determined both subjectively (life satisfaction/ happiness measures), and objectively (e.g. infant mortality levels, female morbidity as an index of population health, access to nutritious food and educational and health resources, etc). These studies do not take into account the large amount of energy that is wasted either through inefficient technologies, or frivolous use, which effective decarbonization strategies seek to reduce.

Other studies that consider the minimal energy needed for wellbeing suggest a much lower level of per capita energy consumption is required. These studies take a different approach and focus on ensuring basic wellbeing is maintained, but not necessarily with all the trappings of a complex industrial society. Their results indicate a level of approximately 20 GJ per capita is adequate.

In either case, we in New Zealand are wasting a lot of energy, both in terms of the efficiency of our technologies (see the Losses and Own Use info above), and also in our uses which do not contribute to wellbeing (think of the private vehicle travel that could be done by active or public transport – if we had good infrastructure in place).

We in New Zealand need a national dialogue about our future. And energy availability is only one aspect. We need to discuss what our carrying capacity is, what level of consumption is sustainable for our population, and whether we wish to make adjustments in either our per capita consumption or our population. Both together determine whether we are on the sustainable side of carrying capacity. Currently we are on the unsustainable side, meaning our way of life cannot endure. Not a good look for being a good ancestor.

The current trajectory of the Government and Electricity Authority appears to be grossly unsustainable. At the very least they should be able to answer the questions posed here about the GHG emissions from implementing a totally renewable energy system, the net energy of such a system, and the related environmental and social consequences.

Public dialogue is critical to collectively working out our future. Allowing the current profit-driven trajectory to unfold is a recipe for disasters for our children and grandchildren.

Being silent on these issues amounts to complicity in allowing short-term financial interests and an addiction to convenience jeopardise a genuinely secure and resilient future. Let’s get some answers from the Government and Electricity Authority to critical questions about energy security.

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EU Energy Price Crisis drives soaring electricity bills as natural gas sets pay-as-clear power prices; leaders debate price caps, common gas purchasing, market reform, renewables, and ETS changes amid Ukraine war supply shocks.

Key Points

A surge in gas-driven power costs linked to pay-as-clear pricing, supply shocks, and policy rifts across the EU market.

✅ Gas sets marginal power price via pay-as-clear mechanism

✅ Spain pushes decoupling and temporary price caps

✅ EU weighs joint gas buying, efficiency, more renewables

Nothing grabs politicians' attention faster than angry voters, and they've had plenty to be furious about as natural gas and electricity bills have soared to stomach-churning levels in recent months, as this UK natural gas analysis illustrates across markets.

That's led to a scramble to figure out ways to get those costs down, with emergency price-limiting measures under discussion — but that's turning out to be very difficult, so the likeliest result is that EU leaders meeting later this week won't come up with any solutions.

“There is no single easy answer to tackle the high electricity prices given the diversity of situations among Member States. Some options are only suitable for specific national contexts,” the European Commission said on Wednesday. “They all carry costs and drawbacks.” 

The initial problem was a surge in gas demand in Asia last year coupled with lower-than-normal Russian gas deliveries that left European gas storage at unusually low levels. Now the war in Ukraine is making matters even worse, as pressure grows for the bloc to rapidly cut its imports of Russian oil, coal and natural gas — although some national leaders reject the economic costs that would entail.

"We will end this dependence as quickly as we can, but to do that from one day to the next would mean plunging our country and all of Europe into a recession," German Chancellor Olaf Scholz warned on Wednesday.

The problem for the bloc is that its liberalized electricity market is tightly tied to the price of natural gas; power prices are set by the final input needed to balance demand — called pay-as-clear — which in most cases is set by natural gas. That's led to countries with large amounts of cheaper renewable or nuclear energy seeing sharp spikes in power prices thanks to the cost of that final bit of gas-fired electricity.

A Spanish-led coalition that includes Portugal, Belgium and Italy wants deep reforms to the EU price model, fueling a broader electricity market revamp debate in Brussels.

Others, such as the Netherlands and Germany, strongly oppose such an approach, echoing how nine countries oppose reforms at the EU level, and want to focus on cushioning the effects of the high prices on consumers and businesses, while letting the market operate. 

A third group, largely in Central Europe, wants to use the price spike to revamp or scrap the bloc's Emissions Trading System and to rethink its Fit for 55 climate legislation.

The European Commission has been holding the middle ground — arguing that the current market model makes sense, but encouraging countries to boost the amount of renewable electricity, in a wake-up call to ditch fossil fuels for Europe, to cut energy use and increase efficiency.

In draft conclusions of this week's European Council summit, seen by POLITICO, EU leaders, amid a France-Germany tussle over reform, call for things like a common approach to buying gas, aimed at preventing countries from competing against each other. But there's no big movement on electricity prices.

“It does not seem realistic to expect a result on the energy discussion at this European Council,” one diplomat said, stressing that the governments will need to see more analysis before committing to any more steps.

Looking for action
Spain wanted a much more robust response. Madrid has been arguing since last summer for “decoupling” gas from the electricity market; together with Portugal, it also mulled limiting the wholesale price of electricity to €180 per megawatt-hour — a proposal that Spain abandoned under fire from industry and consumer groups. 

Now Madrid is pushing to get a specific permission in the summit's final conclusions that would allow countries to voluntarily apply certain short-term solutions such as gas price cap strategies, according to a draft with track changes seen by POLITICO.

The issue with a cap is if gas prices are higher than the cap, Spain might not be able to buy any gas.

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Germany renewable energy milestone 2019 saw wind, solar, hydropower, and biomass outproduce coal and nuclear, as low gas prices and high CO2 costs under the EU ETS reshaped the electricity mix, per Fraunhofer ISE.

Key Points

It marks H1 2019 when renewables supplied 47.3% of Germany's electricity, surpassing coal and nuclear.

✅ Driven by high CO2 prices and cheap natural gas

✅ Wind and solar output rose; coal generation declined sharply

✅ Flexible gas plants outcompeted inflexible coal units

In Lippendorf, Saxony, the energy supplier EnBW is temporarily taking part of a coal-fired power plant offline. Not because someone ordered it — it simply wasn't paying off. Gas prices are low, CO2 prices are high, and with many hours of sunshine and wind, renewable methods are producing a great deal of electricity as part of Germany's energy transition now reshaping operations. And in the first half of the year there was plenty of sun and wind.

The result was a six-month period in which renewable energy sources, a trend echoed by the EU wind and solar record across the bloc, produced more electricity than coal and nuclear power plants together. For the first time 47.3% of the electricity consumers used came from renewable sources, while 43.4% came from coal-fired and nuclear power plants.

In addition to solar and wind power, renewable sources also include hydropower and biomass. Gas supplied 9.3%, reflecting how renewables are crowding out gas across European power markets, while the remaining 0.4% came from other sources, such as oil, according to figures published by the Fraunhofer Institute for Solar Energy Systems in July.

Fabian Hein from the think tank Agora Energiewende stresses that the situation is only a snapshot in time, with grid expansion woes still shaping outcomes. For example, the first half of 2019 was particularly windy and wind power production rose by around 20% compared to the first half of 2018.

Electricity production from solar panels rose by 6%, natural gas by 10%, while the share of nuclear power in German electricity consumption has remained virtually unchanged despite a nuclear option debate in climate policy.

Coal, on the other hand, declined. Black coal energy production fell by 30% compared to the first half of 2018, lignite fell by 20%. Some coal-fired power plants were even taken off the grid, even as coal still provides about a third of Germany's electricity. It is difficult to say whether this was an effect of the current market situation or whether this is simply part of long-term planning, says Hein.

Activists storm German mine in anti-coal protest

It is clear, however, that an increased CO2 price has made the ongoing generation of electricity from coal more expensive. Gas-fired power plants also emit CO2, but less than coal-fired power plants. They are also more efficient and that's why gas-fired power plants are not so strongly affected by the CO2 price

The price is determined at a European level and covers power plants and energy intensive industries in Europe. Other areas, such as heating or transport are not covered by the CO2 price scheme. Since a reform of CO2 emissions trading in 2017, the price has risen sharply. Whereas in September 2016 it was just over €5 ($5.6), by the end of June 2019 it had climbed to over €26.

Ups and downs

Gas as a raw material is generally more expensive than coal. But coal-fired power plants are more expensive to build. This is why operators want to run them continuously. In times of high demand, and therefore high prices, gas-fired power plants are generally started up, as seen when European power demand hit records during recent heatwaves, since it is worth it at these times.

Gas-fired power plants can be flexibly ramped up and down. Coal-fired power plants take 11 hours or longer to get going. That's why they can't be switched on quickly for short periods when prices are high, like gas-fired power plants. In the first half of the year, however, coal-fired power plants were also ramped up and down more often because it was not always worthwhile to let the power plant run around the clock.

Because gas prices were particularly low in the first half of 2019, some gas-fired power plants were more profitable than coal-fired plants. On June 29, 2019, the gas price at the Dutch trading point TTF was around €10 per megawatt hour. A year earlier, it had been almost €20. This is partly due to the relatively mild winter, as there is still a lot of gas in reserve, confirmed a spokesman for the Federal Association of the Energy and Water Industries (BDEW). There are also several new export terminals for liquefied natural gas. Additionally, weaker growth and trade wars are slowing demand for gas. A lot of gas comes to Europe, where prices are still comparatively high, reported the Handelsblatt newspaper.

The increase in wind and solar power and the decline in nuclear power have also reduced CO2 emissions. In the first half of 2019, electricity generation emitted around 15% less CO2 than in the same period last year, reported BDEW. However, the association demands that the further expansion of renewable energies should not be hampered. The target of 65% renewable energy can only be achieved if the further expansion of renewable energy sources is accelerated.

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

Key Points

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

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

✅ PSPS mitigates ignition from damaged transmission infrastructure.

✅ Baseload diversity improves resilience during high-wind events.

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

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

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

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

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

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

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

Wind Speed Limits

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

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

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

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

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

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

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