Solar and wind power curtailments are rising in California


wind and solar power

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CAISO Renewable Curtailments reflect grid balancing under transmission congestion and oversupply, reducing solar and wind output while leveraging WEIM trading, battery storage, and transmission expansion to integrate renewables and stabilize demand-supply.

 

Key Points

CAISO renewable curtailments are reductions in wind and solar output to balance grid amid congestion or oversupply.

✅ Driven mainly by transmission congestion, less by oversupply.

✅ Peaks in spring when demand is low and solar output is high.

✅ Mitigated by WEIM trades, new lines, and battery storage growth.

 

The California Independent System Operator (CAISO), the grid operator for most of the state, is increasingly curtailing solar- and wind-powered electricity generation, as reported in rising curtailments, as it balances supply and demand during the rapid growth of wind and solar power in California.

Grid operators must balance supply and demand to maintain a stable electric system as advances in solar and wind continue to scale. The output of wind and solar generators are reduced either through price signals or rarely, through an order to reduce output, during periods of:

Congestion, when power lines don’t have enough capacity to deliver available energy
Oversupply, when generation exceeds customer electricity demand

In CAISO, curtailment is largely a result of congestion. Congestion-related curtailments have increased significantly since 2019 because California's solar boom has been outpacing upgrades in transmission capacity.

In 2022, CAISO curtailed 2.4 million megawatthours (MWh) of utility-scale wind and solar output, a 63% increase from the amount of electricity curtailed in 2021. As of September, CAISO has curtailed more than 2.3 million MWh of wind and solar output so far this year, even as the US project pipeline is dominated by wind, solar, and batteries.

Solar accounts for almost all of the energy curtailed in CAISO—95% in 2022 and 94% in the first seven months of 2023. CAISO tends to curtail the most solar in the spring when electricity demand is relatively low (because moderate spring temperatures mean less demand for space heating or air conditioning) and solar output is relatively high, although wildfire smoke impacts can reduce available generation during fire season as well.

CAISO has increasingly curtailed renewable generation as renewable capacity has grown in California, and the state has even experienced a near-100% renewables moment on the grid in recent years. In 2014, a combined 9.0 gigawatts (GW) of wind and solar capacity had been built in California. As of July 2023, that number had grown to 17.6 GW. Developers plan to add another 3.0 GW by the end of 2024.

CAISO is exploring and implementing various solutions to its increasing curtailment of renewables, including:

The Western Energy Imbalance Market (WEIM) is a real-time market that allows participants outside of CAISO to buy and sell energy to balance demand and supply. In 2022, more than 10% of total possible curtailments were avoided by trading within the WEIM. A day ahead market is expected to be operational in Spring 2025.

CAISO is expanding transmission capacity to reduce congestion. CAISO’s 2022–23 Transmission Planning Process includes 45 transmission projects to accommodate load growth and a larger share of generation from renewable energy sources.

CAISO is promoting the development of flexible resources that can quickly respond to sudden increases and decreases in demand such as battery storage technologies that are rapidly becoming more affordable. California has 4.9 GW of battery storage, and developers plan to add another 7.6 GW by the end of 2024, according to our survey of recent and planned capacity changes. Renewable generators can charge these batteries with electricity that would otherwise have been curtailed.

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New Kind of 'Solar' Cell Shows We Can Generate Electricity Even at Night

Thermoradiative Diode Power leverages infrared radiation and night-sky cooling to harvest waste heat. Using MCT (mercury cadmium telluride) detectors with photovoltaics, it extends renewable energy generation after sunset, exploiting radiative cooling and low-power density.

 

Key Points

Technology using MCT infrared diodes to turn radiative Earth-to-space heat loss into electricity, aiding solar at night.

✅ MCT diodes radiate to cold sky, generating tiny current at 20 C

✅ Complements photovoltaics by harvesting post-sunset infrared flux

✅ Potential up to one-tenth solar output with further efficiency gains

 

Conventional solar technology soaks up rays of incoming sunlight to bump out a voltage. Strange as it seems, some materials are capable of running in reverse, producing power as they radiate heat back into the cold night sky environment.

A team of engineers in Australia has now demonstrated the theory in action, using the kind of technology commonly found in night-vision goggles to generate power, while other research explores electricity from thin air concepts under ambient humidity.

So far, the prototype only generates a small amount of power, and is probably unlikely to become a competitive source of renewable power on its own – but coupled with existing photovoltaics technology and thermal energy into electricity approaches, it could harness the small amount of energy provided by solar cells cooling after a long, hot day's work.

"Photovoltaics, the direct conversion of sunlight into electricity, is an artificial process that humans have developed in order to convert the solar energy into power," says Phoebe Pearce, a physicist from the University of New South Wales.

"In that sense, the thermoradiative process is similar; we are diverting energy flowing in the infrared from a warm Earth into the cold Universe."

By setting atoms in any material jiggling with heat, you're forcing their electrons to generate low-energy ripples of electromagnetic radiation in the form of infrared light, a principle also explored with carbon nanotube energy harvesters in ambient conditions.

As lackluster as this electron-shimmy might be, it still has the potential to kick off a slow current of electricity. All that's needed is a one-way electron traffic signal called a diode.

Made of the right combination of elements, a diode can shuffle electrons down the street as it slowly loses its heat to a cooler environment.

In this case, the diode is made of mercury cadmium telluride (MCT). Already used in devices that detect infrared light, MCT's ability to absorb mid-and long-range infrared light and turn it into a current is well understood.

What hasn't been entirely clear is how this particular trick might be used efficiently as an actual power source.

Warmed to around 20 degrees Celsius (nearly 70 degrees Fahrenheit), one of the tested MCT photovoltaic detectors generated a power density of 2.26 milliwatts per square meter.

Granted, it's not exactly enough to boil a jug of water for your morning coffee. You'd probably need enough MCT panels to cover a few city blocks for that small task.

But that's not really the point, either, given it's still very early days in the field, and there's potential for the technology to develop significantly further in the future.

"Right now, the demonstration we have with the thermoradiative diode is relatively very low power. One of the challenges was actually detecting it," says the study's lead researcher, Ned Ekins-Daukes.

"But the theory says it is possible for this technology to ultimately produce about 1/10th of the power of a solar cell."

At those kinds of efficiencies, it might be worth the effort weaving MCT diodes into more typical photovoltaic networks alongside thin-film waste heat solutions so that they continue to top up batteries long after the Sun sets.

To be clear, the idea of using the planet's cooling as a source of low-energy radiation is one engineers have been entertaining for a while now. Different methods have seen different results, all with their own costs and benefits, with low-cost heat-to-electricity materials also advancing in parallel.

Yet by testing the limits of each and fine-tuning their abilities to soak up more of the infrared bandwidth, we can come up with a suite of technologies and thermoelectric materials capable of wringing every drop of power out of just about any kind of waste heat.

"Down the line, this technology could potentially harvest that energy and remove the need for batteries in certain devices – or help to recharge them," says Ekins-Daukes.

"That isn't something where conventional solar power would necessarily be a viable option."

 

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California's Looming Green New Car Wreck

California Gas Car Ban 2035 signals a shift to electric vehicles, raising grid reliability concerns, charging demand, and renewable energy challenges across solar, wind, and storage, amid rolling blackouts and carbon-free power mandates.

 

Key Points

An order ending new gasoline car sales by 2035 in California, accelerating EV adoption and pressuring the power grid.

✅ 25% EV fleet could add 232.5 GWh/day charging demand by 2040

✅ Solar and wind intermittency strains nighttime home charging

✅ Grid upgrades, storage, and load management become critical

 

On September 23, California Gov. Gavin Newsom issued an executive order that will ban the sale of gasoline-powered cars in the Golden State by 2035. Ignoring the hard lessons of this past summer, when California’s solar- and wind-reliant electric grid underwent rolling blackouts, Newsom now adds a huge new burden to the grid in the form of electric vehicle charging, underscoring the need for a much bigger grid to meet demand. If California officials follow through and enforce Newsom’s order, the result will be a green new car version of a train wreck.

In parallel, the state is moving on fleet transitions, allowing electric school buses only from 2035, which further adds to charging demand.

Let’s run some numbers. According to Statista, there are more than 15 million vehicles registered in California. Per the U.S. Department of Energy, there are only 256,000 electric vehicles registered in the state—just 1.7 percent of all vehicles, a share that will challenge state power grids as adoption grows.

Using the Tesla Model3 mid-range model as a baseline for an electric car, you’ll need to use about 62 kilowatt-hours (KWh) of power to charge a standard range Model 3 battery to full capacity. It will take about eight hours to fully charge it at home using the standard Tesla NEMA 14-50 charger, a routine that has prompted questions about whether EVs could crash the grid by households statewide.

Now, let’s assume that by 2040, five years after the mandate takes effect, also assuming no major increase in the number of total vehicles, California manages to increase the number of electric vehicles to 25 percent of the total vehicles in the state. If each vehicle needs an average of 62 kilowatt-hours for a full charge, then the total charging power required daily would be 3,750,000 x 62 KWh, which equals 232,500,000 KWh, or 232.5 gigawatt-hours (GWh) daily.

Utility-scale California solar electric generation according to the energy.ca.gov puts utility-scale solar generation at about 30,000 GWh per year currently. Divide that by 365 days and we get 80 GWh/day, predicted to double, to 160 GWh /day. Even if we add homeowner rooftop solar, and falling prices for solar and home batteries in the wake of blackouts, about half the utility-scale, at 40 GWh/day we come up to 200 GW/h per day, still 32 GWh short of the charging demand for a 25% electric car fleet in California. Even if rooftop solar doubles by 2040, we are at break-even, with 240GWh of production during the day.

Bottom-line, under the most optimistic best-case scenario, where solar operates at 100% of rated capacity (it seldom does), it would take every single bit of the 2040 utility-scale solar and rooftop capacity just to charge the cars during the day. That leaves nothing left for air conditioning, appliances, lighting, etc. It would all go to charging the cars, and that’s during the day when solar production peaks.

But there’s a much bigger problem. Even a grade-schooler can figure out that solar energy doesn’t work at night, when most electric vehicles will be charging at homes, even as some officials look to EVs for grid stability through vehicle-to-grid strategies. So, where does Newsom think all this extra electric power is going to come from?

The wind? Wind power lags even further behind solar power. According to energy.gov, as of 2019, California had installed just 5.9 gigawatts of wind power generating capacity. This is because you need large amounts of land for wind farms, and not every place is suitable for high-return wind power.

In 2040, to keep the lights on with 25 percent of all vehicles in California being electric, while maintaining the state mandate requiring all the state’s electricity to come from carbon-free resources by 2045, California would have to blanket the entire state with solar and wind farms. It’s an impossible scenario. And the problem of intermittent power and rolling blackouts would become much worse.

And it isn’t just me saying this. The U.S. Environmental Protection Agency (EPA) agrees. In a letter sent by EPA Administrator Andrew Wheeler to Gavin Newsom on September 28, Wheeler wrote:

“[It] begs the question of how you expect to run an electric car fleet that will come with significant increases in electricity demand, when you can’t even keep the lights on today.

“The truth is that if the state were driving 100 percent electric vehicles today, the state would be dealing with even worse power shortages than the ones that have already caused a series of otherwise preventable environmental and public health consequences.”


California’s green new car wreck looms large on the horizon. Worse, can you imagine electric car owners’ nightmares when California power companies shut off the power for safety reasons during fire season? Try evacuating in your electric car when it has a dead battery.

Gavin Newsom’s “no more gasoline cars sold by 2035” edict isn’t practical, sustainable, or sensible, much like the 2035 EV mandate in Canada has been criticized by some observers. But isn’t that what we’ve come to expect with any and all of these Green New Deal-lite schemes?

 

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The American EV boom is about to begin. Does the US have the power to charge it?

EV Charging Infrastructure accelerates with federal funding, NEVI corridors, and Level 2/3 DC fast charging to cut range anxiety, support apartment dwellers, and scale to 500,000 public chargers alongside tax credits and state mandates.

 

Key Points

The network of public and private hardware, software, and policies enabling reliable Level 2/3 EV charging at scale.

✅ $7,500/$4,000 tax credits spur adoption and charger demand

✅ NEVI funding builds 500,000 public, reliable DC fast chargers

✅ Equity focus: apartment, curbside, bidirectional and inductive tech

 

Speaking in front of a line of the latest electric vehicles (EVs) at this month’s North American International Auto Show, President Joe Biden declared: “The great American road trip is going to be fully electrified.”

Most vehicles on the road are still gas guzzlers, but Washington is betting big on change, with EV charging networks competing to expand as it hopes that major federal investment will help reach a target set by the White House for 50% of new cars to be electric by 2030. But there are roadblocks – specifically when it comes to charging them all. “Range anxiety,” or how far one can travel before needing to charge, is still cited as a major deterrent for potential EV buyers.

The auto industry recently passed the 5% mark of EV market share – a watershed moment, arriving ahead of schedule according to analysts, before rapid growth. New policies at the state and local level could very well spur that growth: the Inflation Reduction Act, which passed this summer, offers tax credits of $4,000 to purchase a used EV and up to $7,500 for certain new ones. In August, California, the nation’s largest state and economy, announced rules that would ban all new gas-powered cars by 2035, as part of broader grid stability efforts in the state. New York plans to follow.

So now, the race is on to provide chargers to power all those new EVs.

The administration’s target of 500,000 public charging units by 2030 is a far cry from the current count of nearly 50,000, according to the Department of Energy’s estimate. And those new chargers will have to be fast – what’s known as Level 2 or 3 charging – and functional in order to create a truly reliable system, even as state power grids face added demands across regions. Today, many are not.

Last week, the White House approved plans for all 50 states, along with Washington DC, and Puerto Rico, to set up chargers along highways, unlocking $1.5bn in federal funding to that end, as US automakers’ charger buildout to complement public funds. The money comes from the landmark infrastructure bill passed last year, which invests $7.5bn for EV charging in total.

But how much of that money is spent is largely going to be determined at the local level, amid control over charging debates among stakeholders. “It’s a difference between policy and practice,” said Drew Lipsher, the chief development officer at Volta, an EV charging provider. “Now that the federal government has these policies, the question becomes, OK, how does this actually get implemented?” The practice, he said, is up to states and municipalities.

As EV demand spikes, a growing number of cities are adopting policies for EV charging construction. In July, the city of Columbus passed an “EV readiness” ordinance, which will require new parking structures to host charging stations proportionate to the number of total parking spots, with at least one that is ADA-accessible. Honolulu and Atlanta have passed similar measures.

One major challenge is creating a distribution model that can meet a diversity of needs.

At the moment, most EV owners charge their cars at home with a built-in unit, which governments can help subsidize. But for apartment dwellers or those living in multi-family homes, that’s less feasible. “When we’re thinking about the largest pieces of the population, that’s where we need to really be focusing our attention. This is a major equity issue,” said Alexia Melendez Martineau, the policy manager at Plug-In America, an EV consumer advocacy group.

Bringing power to people is one such solution. In Hoboken, New Jersey, Volta is working with the city to create a streetside charging network. “The network will be within a five-minute walk of every resident,” said Lipsher. “Hopefully this is a way for us to really import it to cities who believe public EV charging infrastructure on the street is important.” Similarly, in parts of Los Angeles – as in Berlin and London – drivers can get a charge from a street lamp.

And there may be new technologies that could help, exciting experts and EV enthusiasts alike. That could include the roads themselves charging EVs through a magnetizable concrete technology being piloted in Indiana and Detroit. And bidirectional charging, where, similar to solar panels, drivers can put their electricity back into the grid – or perhaps even to another EV, through what’s known as electric vehicle supply equipment (EVSE). Nissan approved the technology for their Leaf model this month.

 

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0 to 180 km in 10 minutes: B.C. Hydro rolls out faster electric vehicle charging

B.C. Hydro fast EV charging stations roll out 180 kW DC fast chargers, power sharing, and rural network expansion in Surrey, Manning Park, Mackenzie, and Tumbler Ridge to ease range anxiety across northern B.C.

 

Key Points

180 kW DC chargers with power sharing, expanding B.C.'s rural EV network to cut range anxiety and speed up recharging.

✅ 180 kW DC fast charging: ~180 km added in about 10 minutes

✅ Power sharing enables two vehicles to use one unit simultaneously

✅ Expands rural charging coverage to cut range anxiety for northern B.C.

 

B.C. Hydro has unveiled plans to install new charging stations it says can add as much as 180 kilometres worth of range to the average electric vehicle in 10 minutes.

The utility says the new 180-kilowatt units will be added to its network, expanding stations in southern B.C. as soon as this fall, with even more scheduled to arrive in 2024.

The first communities to get the new faster-charge stations are Surrey, Manning Park and, north of Prince George, Mackenzie and Tumbler Ridge, while the Lillooet fast-charging site is already operational.

B.C. Hydro president Chris O'Riley says both current and prospective electric vehicle owners have said they want improved coverage in more rural parts of the province in order to address range anxiety, as the utility has warned of a potential EV charging bottleneck if demand outpaces infrastructure.

"We are listening to feedback from our customers," he said.

The new stations will also be the first from B.C. Hydro to offer power sharing, which lets two different vehicles use the same unit to charge at the same time.

The adoption of electric vehicles in B.C. is much higher in southern urban areas than rural, northern ones, according to statistics from the provincial government made available in 2022, as the province leads the country in going electric according to recent reports.

The figures showed about one in every 45 people owns a zero-emission vehicle in the southwest regions of the province, but that number drops to one in 232 in the Kootenays, where the region makes electric cars a priority through local initiatives, and one in 414 in northern B.C.

The number of public charging stations closely corresponds to the number of zero-emission vehicles in various regions.

The Vancouver area has more than 500 fast-charging ports, according to ChargeHub, a website that tracks charging stations in North America. 

In contrast, the route from Prince George to Fort Nelson via Dawson Creek along Highway 97, part of the B.C. Electric Highway network connecting the region — a distance of more than 800 kilometres — has just three locations where a vehicle can be charged to 80 per cent power in an hour or less, creating challenges for people hoping to travel the route.

The disparity is also clear in a just-published analysis from the non-profit Community Energy Association, which acts as an advisory group to government associations. 

It found that while there is roughly one charging port every three square kilometres in Metro Vancouver, the number drops to one every 250 square kilometres in the Regional District of East Kootenay and one every 3,500 square kilometres in the Peace River Regional District, in the province's northeast.

"The more infrastructure we can get across the region ... the more the adoption of electric vehicles will increase," said the association's director of transportation initiatives, Danielle Weiss.

"We are excited to hear that B.C. Hydro is also viewing rural areas as a key focus for their new, enhanced charging technology."

B.C. Hydro says it currently has 153 charging units at 84 locations across the province with plans to add an additional 3,000 ports over the next 10 years, with provincial EV charger rebates supporting home and workplace installations as well.

 

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Feds announce $500M contract with Edmonton company for green electricity

Canada Renewable Energy Partnerships advance wind power and clean electricity in Alberta and Saskatchewan, cutting emissions and supporting net-zero goals through Capital Power and SaskPower agreements with Indigenous participation and 25-year supply contracts.

 

Key Points

Government-backed deals with Capital Power and SaskPower to deliver clean electricity and reduce emissions.

✅ 25-year renewable supply for federal facilities

✅ New Halkirk 2 Wind project in Alberta

✅ Emissions cuts with Indigenous participation

 

The Government of Canada has partnered with two major energy providers in Western Canada (Prairie provinces) on renewable energy projects.

Tourism Minister Randy Boissonnault appeared in Edmonton on Friday to announce a new Alberta wind-generation facility in partnership with Capital Power.

It's one of two new energy partnerships in Western Canada as part of the 2030 emissions reduction plan by Public Services and Procurement Canada.

On Jan. 1, the federal government awarded a contract worth up to $500 million to Capital Power to provide all federal facilities in Alberta with renewable electricity as part of Alberta's renewable energy surge for 25 years.

"We're proud to partner with the government of Canada to help them reach their 100 per cent clean electricity by 2025 goal," said Jason Comandante, Capital Power vice president of commercial services.

The agreement also includes opportunities for Indigenous participation, including facility development partnerships and employment and training opportunities.

"At Capital Power, we are committed to net-zero by 2045, and are proud to take action against climate change. Collaborative agreements like this help support our net-zero goals, provide us opportunities to meaningfully engage Indigenous communities, and help decarbonize Alberta's power grid," Comandante said.

Capital Power will provide around 250,000 megawatt-hours of electricity each year through existing renewable energy credits while the new Capital Power Halkirk 2 Wind facility is being developed.

Located near Paintearth, Alta., the proposed wind farm will have up to 35 turbines and generate enough power for the average yearly electricity needs of more than 70,000 Alberta homes.

The project is currently awaiting regulatory approval, within Alberta's energy landscape, with construction projected to begin this summer. When complete, it will supply 49 per cent of its output to the federal government.

"Through the agreement, the federal government is supporting the ongoing development of renewable energy infrastructure development within the province," Boissonnault said.

The new partnership will join another in Saskatchewan and complement Alberta solar facilities that have been contracted at lower cost than natural gas.

In 2022, the federal government signed an agreement with SaskPower to supply clean electricity to the approximately 600 federal facilities in Saskatchewan. That wind project is expected to come online by 2024.

Boissonnault said the two initiatives combined will reduce carbon dioxide emissions in Alberta and Saskatchewan by about 166 kilotonnes.

"That is the equivalent of the emissions from more than 50,000 cars driven for one year. So, if you think about that, that's a great reduction right here in Alberta and Saskatchewan," he said.

"These are concrete steps to ensuring that Canada remains a leader of renewable energy on the global stage and grid modernization projects to help the fight against climate change." 

 

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New legislation will make it easier for strata owners to install EV charging stations

BC Strata EV Charging Reforms streamline approvals under the Strata Property Act, lowering the voting threshold and requiring an electrical planning report to expand EV charging stations in multi-unit strata buildings across British Columbia.

 

Key Points

BC reforms ease EV charger installs in stratas by lowering votes, requiring plans, and fast-tracking compliant requests.

✅ Vote threshold drops to 50% for EV infrastructure

✅ Electrical planning report required for stratas

✅ Stratas must approve compliant owner charging requests

 

Owning an electric vehicle (EV) will be a little easier for strata property owners, the province says, after announcing changes to legislation to facilitate the installation of charging stations in strata buildings.

On Thursday, the province said it would be making amendments to the Strata Property Act, the legal framework all strata corporations are required to follow, and align with practical steps for retrofitting condos with chargers in older buildings.

Three areas will improve access to EV charging stations in strata complexes, the province says, including lowering the voting threshold from 75 per cent to 50 per cent for approval of the costs, supported by EV charger rebates that can offset expenses, and changes to the property that are needed to install them, as well as requiring strata corporations to have an electrical planning report to make installation of these stations easier.

The amendments would mean stratas would have to approve owners' requests for such charging stations, even amid high-rise EV charging challenges reported across Canada, as long as "reasonable criteria are met."

Minister of Energy, Mines and Low Carbon Innovation Josie Osborne said people are more likely to buy an electric vehicle if they have the ability to charge it — something that's lacking for many British Columbians living in multi-unit residences, where Vancouver's EV-ready policy is setting a local example for multi-family buildings. 

"B.C. has one of the largest public electric vehicle charging networks in Canada, and leads the country in going electric, but we need to make it easier for more people to charge their EVs at home," Osborne said in a statement.

Tony Gioventu, the executive director of the Condominium Home Owners Association of B.C., said the new legislation strikes a balance between allowing people access to EV charging stations, as examples from Calgary apartments and condos demonstrate, while also ensuring stratas still have control over their properties. 

This is just the latest step in the B.C. government's move to get more EVs on the road: alongside rebates for home and workplace charging, the province passed the Zero-Emission Vehicles Act, which aims for 10 per cent of all new light-duty cars and trucks sold in B.C. to be zero emission by 2025. By 2040, they'll all need to be emission-free.

 

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