Olympus to Use 100% Renewable Electricity

Canada Coal Phase-Out Costs highlight Fraser Institute findings on renewable energy, wind and solar integration, grid reliability, natural gas backup, GDP impacts, greenhouse gas emissions reductions, nuclear alternatives, and transmission upgrades across provincial electricity systems.

Key Points

Costs to replace coal with renewables, impacting taxpayers and ratepayers while ensuring grid reliability.

✅ Fraser Institute estimates $16.8B-$33.7B annually for renewables.

✅ Emissions cut from coal phase-out estimated at only 7.4% nationally.

✅ Natural gas backup and grid upgrades drive major cost increases.

Replacing coal-fired electricity with renewable energy will cost Canadian taxpayers and hydro ratepayers up to $33.7 billion annually, with only minor reductions in global greenhouse gas emissions linked to climate change, according to a new study by the Fraser Institute.

The report, Canadian Climate Policy and its Implications for Electricity Grids by University of Victoria economics professor G. Cornelis van Kooten, said replacing coal-fired electricity with wind and solar power would only cut Canada’s annual emissions by 7.4%,

Prime Minister Justin Trudeau’s has promised a reduction of 40%-45% compared to Canada’s 2005 emissions by 2030, and progress toward the 2035 clean electricity goals remains uncertain.

The study says emission cuts would be relatively small because coal accounted for only 9.2% of Canada’s electricity generation in 2017. (According to Natural Resources Canada, that number is lower today at 7.4%).

In 2019, the last year for which federal data are available, Canada’s electricity sector generated 8.4% of emissions nationally — 61.1 million tonnes out of 730 million tonnes.

“Despite what advocates, claim, renewable power — including wind and solar — isn’t free and, as Europe's power crisis lessons suggest, comes with only modest benefits to the environment,” van Kooten said.

“Policy makers should be realistic about the costs of reducing greenhouse gas emissions in Canada, which accounts for less than 2% of emissions worldwide.”

The report says the increased costs of operating the electricity grid across Canada — between $16.8 billion and $33.7 billion annually or 1% to 2% of Canada’s annual GDP — would result from having to retain natural gas, consistent with net-zero regulations allowing some natural gas in limited cases, as a backup to intermittent wind and solar power, which cannot provide baseload power to the electricity grid on demand.

Van Kooten said his cost estimates are conservative because his study “could not account for scenarios where the scale of intermittency turned out worse than indicated in our dataset … the costs associated with the value of land in other alternative uses, the need for added transmission lines, as analyses of greening Ontario's grid costs indicate, environmental and human health costs and the life-cycle costs of using intermittent renewable sources of energy, including costs related to the disposal of hazardous wastes from solar panels and wind turbines.”

If nuclear power was used to replace coal-fired electricity, the study says, costs would drop by half — $8.3 billion to $16.7 billion annually — but that’s unrealistic because of the time it takes to build nuclear plants and public opposition to them.

The study says to achieve the federal government’s target of reducing emissions to 40% to 45% below 2005 levels by 2030 and net-zero emissions by 2050, would require building 30 nuclear power plants before 2030, highlighting Canada’s looming power problem as described by analysts — meaning one plant of 1,000-megawatt capacity coming online every four months between now and 2030.

Alternatively, it would take 28,340 wind turbines, each with 2.5-megawatts capacity, or 1,050 turbines being built every four months, plus the costs of upgrading transmission infrastructure.

Van Kooten said he based his calculations on Alberta, which generates 39.8% of its electricity from coal and the cost of Ontario eliminating coal-fired electricity, even as Ontario electricity getting dirtier in coming years, which generated 25% of its electricity, between 2003 and 2014, replacing it with a combination of natural gas, nuclear and wind and solar power.

According to Natural Resources Canada, Nova Scotia generates 49.9% of its electricity from coal, Saskatchewan 42.9%, and New Brunswick 17.2%.

In 2018, the Trudeau government announced plans to phase-out traditional coal-fired electricity by 2030, though the Stop the Shock campaign seeks to bring back coal power in some regions. 

Canada and the U.K. created the “Powering Past Coal Alliance” in 2017, aimed at getting other countries to phase out the use of coal to generate electricity.

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Canada Offshore Wind Amendments streamline offshore energy regulators in Nova Scotia and Newfoundland and Labrador, enabling green hydrogen, submerged land licences, regional assessments, MPAs standards, while raising fisheries compensation, navigation, and Indigenous consultation considerations.

Key Points

Reforms assign offshore wind to joint regulators, enable seabed licensing, and address fisheries and Indigenous issues.

✅ Assigns wind oversight to Canada-NS and Canada-NL offshore regulators

✅ Introduces single submerged land licence and regional assessments

✅ Addresses fisheries, navigation, MPAs, and Indigenous consultation

Canada's offshore accords with Nova Scotia and Newfoundland and Labrador are being updated to promote development of offshore wind farms, but it's not clear yet whether any compensation will be paid to fishermen displaced by wind farms.

Amendments introduced Tuesday in Ottawa by the federal government assign regulatory authority for wind power to jointly managed offshore boards — now renamed the Canada-Nova Scotia Offshore Energy Regulator and Canada-Newfoundland and Labrador Offshore Energy Regulator.

Previously the boards regulated only offshore oil and gas projects.

The industry association promoting offshore wind development, Marine Renewables Canada, called the changes a crucial step.

"The tabling of the accord act amendments marks the beginning of, really, a new industry, one that can play a significant role in our clean energy future," said  Lisen Bassett, a spokesperson for Marine Renewables Canada. 

Nova Scotia's lone member of the federal cabinet, Immigration Minister Sean Fraser, also talked up prospects at a news conference in Ottawa.

'We have lots of water'

"The potential that we have, particularly when it comes to offshore wind and hydrogen is extraordinary," said Fraser.

"There are real projects, like Vineyard Wind, with real investors talking about real jobs."

Sharing the stage with assembled Liberal MPs from Nova Scotia and Newfoundland and Labrador was Nova Scotia Environment Minister Tim Halman, representing a Progressive Conservative government in Halifax.

"If you've ever visited us or Newfoundland, you know we have lots of water, you know we have lots of wind, and we're gearing up to take advantage of those natural resources in a clean, sustainable way. We're paving the way for projects such as offshore wind, tidal energy in Nova Scotia, and green hydrogen production," said Halman.

Before a call for bids is issued, authorities will identify areas suitable for development, conservation or fishing.

The legislation does not outline compensation to fishermen excluded from offshore areas because of wind farm approvals.

Regional assessments

Federal officials said potential conflicts can be addressed in regional assessments underway in both provinces.

Minister of Natural Resources of Canada Jonathan Wilkinson said fisheries and navigation issues will have to be dealt with.

"Those are things that will have to be addressed in the context of each potential project. But the idea is obviously to ensure that those impacts are not significant," Wilkinson said.

Speaking after the event, Christine Bonnell-Eisnor, chair of what is still called the Canada Nova Scotia Offshore Petroleum Board, said what compensation — if any — will be paid to fishermen has yet to be determined.

"It is a question that we're asking as well. Governments are setting the policy and what terms and conditions would be associated with a sea bed licence. That is a question governments are working on and what compensation would look like for fishers."

Scott Tessier, who chairs  the Newfoundland Board, added "the experience has been the same next door in Nova Scotia, the petroleum sector and the fishing sector have an excellent history of cooperation and communication and I don't expect it look any different for offshore renewable energy projects."

Nova Scotia in a hurry to get going

The legislation says the offshore regulator would promote compensation schemes developed by industry and fishing groups linked to fishing gear.

Nova Scotia is in a hurry to get going.

The Houston government has set a target of issuing five gigawatts of licences for offshore wind by 2030, with leasing starting in 2025, reflecting momentum in the U.S. offshore wind market as well. It is intended largely for green hydrogen production. That's almost twice the province's peak electricity demand in winter, which is 2.2 gigawatts.

The amendments will streamline seabed approvals by creating a single "submerged land" licence, echoing B.C.'s streamlined process for clean energy projects, instead of the exploration, significant discovery and production licences used for petroleum development.

Federal and provincial ministers will issue calls for bids and approve licences, akin to BOEM lease requests seen in the U.S. market.

The amendments will ensure Marine Protected Area's  (MPAs) standards apply in all offshore areas governed by the regulations.

Marine protected areas

Wilkinson suggested, but declined, three times to explicitly state that offshore wind farms would be excluded from within Marine Protected Areas.

After this story was initially published on Tuesday, Natural Resources Canada sent CBC a statement indicating offshore wind farms may be permitted inside MPAs.

Spokesperson Barre Campbell noted that all MPAs established in Canada after April 25, 2019, will be subject to the Department of Fisheries and Oceans new standards that prohibit key industrial activities, including oil and gas exploration, development and production.

"Offshore renewable energy activities and infrastructure are not key industrial activities," Campbell said in a statement.

"Other activities may be prohibited, however, if they are not consistent with the conservation objectives that are established by the relevant department that has or that will establish a marine protected area."

Federal impact assessment process

The new federal impact assessment process will apply in offshore energy development, and recent legal rulings such as the Cornwall wind farm decision highlight how courts can influence project timelines.

For petroleum projects, future significant discovery licences will be limited to 25 years replacing the current indefinite term.

Existing significant discovery licences have been an ongoing exception and are not subject to the 25-year limit. Both offshore energy regulators will be given the authority to fulfil the Crown's duty to consult with Indigenous peoples

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Germany Renewable Energy Milestone marks renewables supplying 53% of power, with record onshore wind and peak solar; hydrogen-ready gas plants and grid upgrades are planned to balance variability amid Germany's coal phase-out.

Key Points

It marks renewables supplying 53% of Germany's power, driven by wind and solar records in the energy transition.

✅ 53% of generation and 52% of consumption in 2024

✅ Onshore wind hit record; June solar peaked

✅ 24 GW hydrogen-ready gas plants planned for grid balancing

For the first time, renewable energy sources have surpassed half of Germany's electricity production this year, as indicated by data from sustainable energy organizations.

Preliminary figures from the Center for Solar Energy and Hydrogen Research alongside the German Association of Energy and Water Industries (BDEW) show that the contribution of green energy has risen to 53%, echoing how renewable power surpassed fossil fuels in Europe recently, a significant increase from 44% in the previous year.

The year saw a record output from onshore wind energy, as investments in European wind power climbed, and an unprecedented peak in solar energy production in June, as reported by the organizations. Additionally, renewable sources constituted 52% of Germany's total power consumption, marking an increase of approximately five percentage points.

Germany, Europe's leading economy, heavily impacted by Russia's reduced natural gas supplies last year, as Europeans push back from Russian oil and gas across the region, has been leaning on renewable sources to bridge the energy gap. This shift comes even as the country temporarily ramped up coal usage last winter. Having phased out its nuclear power plants earlier this year, Germany aims for an 80% clean energy production by 2030.

In absolute numbers, Germany produced a record level of renewable energy this year, supported by a solar power boost during the energy crisis, approximately 267 billion kilowatt-hours, according to the associations. A decrease of 11% in overall energy production facilitated a reduced reliance on fossil fuels.

However, Europe's transition to more sustainable energy sources, particularly offshore wind, has encountered hurdles such as increased financing and component costs, even as neighbors like Ireland pursue an ambitious green electricity goal within four years. Germany continues to face challenges in expanding its renewable energy capacity, as noted by BDEW’s executive board chairwoman, Kerstin Andreae.

Andreae emphasizes that while energy companies are eager to invest in the transition, they often encounter delays due to protracted approval processes, bureaucratic complexities, and scarcity of land despite legislative improvements.

German government officials are close to finalizing a strategy this week for constructing multiple new gas-fired power plants, despite findings that solar plus battery storage can be cheaper than conventional power in Germany, a plan estimated to cost around 40 billion euros ($44 billion). This initiative is a critical part of Germany's strategy to mitigate potential power shortages that might result from the discontinuation of coal power, particularly given the variability in renewable energy sources.

A crucial meeting involving representatives from the Economy and Finance Ministries, along with the Chancellor's Office, is expected to occur late Tuesday. The purpose is to finalize this agreement, according to sources who requested anonymity due to restrictions on public disclosure.

The Economy Ministry, spearheading this project, confirmed that intensive discussions are ongoing, although no further details were disclosed.

Germany's plan involves utilizing approximately 24 gigawatts (GW) of energy from hydrogen, including emerging offshore green hydrogen options, and gas-fired power plants to compensate for the fluctuations in wind and solar power generation. However, the proposal has faced challenges, particularly regarding the allocation of public funds for these projects, with disagreements arising with the European Union's executive in Brussels.

Environmental groups have also expressed criticism of the strategy. They advocate for an expedited end to fossil fuel usage and remain skeptical about the energy sector's arguments favoring natural gas as a transitional fuel. Despite natural gas emitting less carbon dioxide than coal, environmentalists question its role in Germany's energy future.

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Tesla Q2 2020 earnings highlight resilient electric vehicles as production and deliveries outpace legacy automakers, while Gigafactory Austin advances, solar installations slump, and energy storage, Megapack, and free cash flow expand despite COVID-19 disruptions.

Key Points

Tesla posted a fourth consecutive profit, strong cash, EV resilience, solar slump, and rising energy storage.

✅ Fourth straight profit and $418M free cash flow

✅ EV output and deliveries fell just 5% year over year

✅ Solar hit record low; storage rose 61% to 419 MWh

Tesla survived the throes of the coronavirus pandemic relatively unscathed, chalking up its fourth sequential quarterly profit for the first time on Wednesday.

On the energy front, however, things were much more complicated: Tesla reported its worst-ever quarter for solar installations but huge growth in its battery business, amid expectations for cheaper, more powerful batteries expected in coming years. CEO Elon Musk nevertheless predicted the energy business will one day rival its car division in scale.

But today, Tesla's bottom line is all about electric vehicles, and the temporary halt of activity at Tesla's Fremont factory due to local health orders didn’t put much of a dent in vehicle production and delivery. Both figures declined 5 percent compared to the same quarter in 2019. In contrast, Q2 vehicle sales at legacy carmakers Ford, GM and Fiat Chrysler declined by one-third or more year-over-year, even as the U.S. EV market share dipped in early 2024 for context.

The costs of factory closures and a $101 million CEO award milestone for Elon Musk didn’t stop Tesla from achieving $418 million in free cash flow, a major improvement over the prior quarter. Cash and cash equivalents grew by $535 million to $8.6 billion during the quarter.

Musk praised his employees for “exceptional execution.” 

“There were so many challenges, too numerous to name, but they got it done,” he said on an investor call Wednesday.

Musk also confirmed that Tesla will build a new Gigafactory in Austin, Texas, five minutes from the airport. The 2,000-acre campus will abut the Colorado River and is “basically going to be an ecological paradise,” he said. The new Texas factory will build the Cybertruck, Semi, Model 3 and Model Y for the Eastern half of North America. Fremont, California will produce the S and X, and make Model 3 and Model Y for the West, in a state where EVs exceed 20% of sales according to recent data.

Return of the Tesla solar slump

This was the first entire quarter affected by the coronavirus response, which threw the rooftop solar industry into turmoil by cutting off in-person sales. Other installers scrambled to shift to digital-first sales strategies, but Tesla had already done so months before lockdowns were imposed.

Q2, then, offers a test case on whether Tesla’s pivot to passive online sales made it better able to deal with stay-at-home orders than its peers. The other publicly traded solar installers have not yet reported their Q2 performance, but Tesla delivered its worst-ever quarterly solar figures: Installations totaled just 27 megawatts. That’s a 7 percent decline from Q2 2019, its previous worst quarter ever for solar.

Musk did not address that weak performance in his remarks to investors, opting instead to highlight the company’s late-June decision to offer the cheapest solar pricing in the country. “We’re the company to go to,” he said of rooftop solar. “It’s only going to get better later this year.”

But the sales slump indicates Tesla’s online sales model could not withstand a historically tough season for residential solar.

"Every single residential installer in the country is going to have a bad Q2 because of the initial impacts of COVID on the market," said Austin Perea, senior solar analyst at Wood Mackenzie. "It's hard to disaggregate the impacts of COVID from their own individual strategies."

Tesla's 23 percent decline in quarter-over-quarter solar installations was not as bad as the expected Q2 decline across the rooftop solar industry, Perea added.

On the vehicle side, Tesla’s sales declined less than did those of major automakers. It’s possible that the same pattern will hold for solar; a less severe drop than those seen by Sunrun or Vivint could be claimed as a victory of sorts. But this quarter made clear that Q2 2019 was not the bottom for Tesla’s solar operation, which once led the residential market as SolarCity but significantly diminished since Tesla acquired it in 2016.

Tesla currently stands in third place for residential solar installers. But No. 1 installer Sunrun said this month that it will acquire No. 2 installer Vivint Solar, making Tesla the second-largest installer by default. That major consolidation in the rooftop solar market went unremarked upon in Tesla's investor call.

Solar and energy storage revenue currently equate to just 7 percent of the company's automotive revenue. But Musk reiterated his prediction that this won’t always be the case. “Long term, Tesla Energy will be roughly the same size as Tesla Automotive,” he said on Wednesday's call.

The grid storage business offered more reason for optimism: Capacity deployed grew 61 percent from the first quarter, rising to 419 megawatt-hours. The prepackaged, large-format Megapack product turned its first profit that quarter.

"Difficult to predict" performance in the second half of 2020
Tesla withdrew its financial guidance last quarter in light of the upheaval across the global economy. It refrained from setting new guidance now.

“Although we have successfully ramped vehicle production back to prior levels, it remains difficult to predict whether there will be further operational interruptions or how global consumer sentiment will evolve, given risks to the EV boom noted by analysts, in the second half of 2020,” the earnings report notes.

The company asserted it will still deliver 500,000 vehicles this year regardless of externalities, a goal that aligns with broader EV sales momentum in 2024 trends. It already has sufficient production capacity installed to reach that, Tesla said. But with 179,387 cars delivered so far, Tesla faces an uphill climb to ship more cars in the second half.

Wall Street maintained its buoyant confidence in Tesla's share price, despite rising competition in China noted by rivals. It closed at $1,592 before the earnings announcement, rising to $1,661 in after-hours trading.

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California EV Adoption leads the U.S., with 37% of registered electric vehicles and 27% of charging locations, spanning Level 1, Level 2, and DC Fast stations, aligned with OCPI and boosted by CALeVIP funding.

Key Points

California EV adoption reflects the state's leading EV registrations and growth in private charging infrastructure.

✅ 37% of U.S. EVs, 27% of charging locations in 2022

✅ CALeVIP funding boosts public charging deployment

✅ OCPI-aligned data; EVs per charger rose to 75 in CA

California has consistently been at the forefront of electric vehicle (EV) adoption, with EV sales topping 20% in California underscoring this trend, and the proliferation of EV charging stations in the United States, maintaining this position since 2016. According to recent estimates from our State Energy Data System (SEDS), California accounts for 37% of registered light-duty EVs in the U.S. and 27% of EV charging locations as of the end of 2022.

The vehicle stock data encompass all registered on-road, light-duty vehicles and exclude any previous vehicle sales no longer in operation. The data on EV charging locations include both private and public access stations for Legacy, Level 1, Level 2, and DC Fast charging ports, excluding EV chargers in single-family residences. There is a data series break between 2020 and 2021, when the U.S. Department of Energy updated its data to align with the Open Charge Point Interface (OCPI) international standard, reflecting changes in the U.S. charging infrastructure landscape.

In 2022, the number of registered EVs in the United States, with U.S. EV sales soaring into 2024 nationwide, surged to six times its 2016 figure, growing from 511,600 to 3.1 million, while the number of U.S. charging locations nearly tripled, rising from 19,178 to 55,015. Over the same period, California saw its registered EVs more than quadruple, jumping from 247,400 to 1.1 million, and its charging locations tripled, increasing from 5,486 to 14,822.

California's share of U.S. EV registrations has slightly decreased in recent years as EV adoption has spread across the country, with Arizona EV ownership relatively high as well. In 2016, California accounted for approximately 48% of light-duty EVs in the United States, which was approximately 12 times more than the state with the second-highest number of EVs, Georgia. By 2022, California's share had decreased to around 37%, which was still approximately six times more than the state with the second-most EVs, Florida.

On the other hand, California's share of U.S. EV charging locations has risen slightly in recent years, as charging networks compete amid federal electrification efforts and partly due to the California Electric Vehicle Infrastructure Project (CALeVIP), which provides funding for the installation of publicly available EV charging stations. In 2016, approximately 25% of U.S. EV charging locations were in California, over four times as many as the state with the second-highest number, Texas. In 2022, California maintained its position with over four times as many EV charging locations as the state with the second-most, New York.

The growth in the number of registered EVs has outpaced the growth of EV charging locations in the United States, and in 2021 plug-in vehicles traveled 19 billion electric miles nationwide, underscoring utilization. In 2016, there were approximately 27 EVs per charging location on average in the country. Alaska had the highest ratio, with 67 EVs per charging location, followed by California with 52 vehicles per location.

In 2022, the average ratio was 55 EVs per charging location in the United States, raising questions about whether the grid can power an ongoing American EV boom ahead. New Jersey had the highest ratio, with 100 EVs per charging location, followed by California with 75 EVs per location.

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Electric Car Motors convert electricity to torque via rotor-stator magnetic fields, using AC/DC inverters, permanent magnets or induction designs; they power EV powertrains efficiently and enable regenerative braking for energy recovery and control.

Key Points

Electric car motors turn electrical energy into wheel torque using rotor-stator fields, inverters, and AC or DC control.

✅ AC induction, PMSM, BLDC, and reluctance architectures explained

✅ Inverters manage AC/DC, voltage, and motor speed via frequency

✅ Regenerative braking recovers energy and reduces wear

When was the last time you stopped to think about how electric cars actually work, especially if you're wondering whether to buy an electric car today? We superfans of the car biz have mostly developed a reasonable understanding of how combustion powertrains work. Most of us can visualize fuel and air entering a combustion chamber, exploding, pushing a piston down, and rotating a crankshaft that ultimately turns the wheels. We generally understand the differences between inline, flat, vee-shaped, and maybe even Wankel rotary combustion engines.

Mechanical engineering concepts such as these are comparatively easy to comprehend. But it's probably a fair bet to wager that only a minority of folks reading this can explain on a bar napkin exactly how invisible electrons turn a car's wheels or how a permanent-magnet motor differs from an AC induction one. Electrical engineering can seem like black magic and witchcraft to car nuts, so it's time to demystify this bold new world of electromobility, with the age of electric cars arriving ahead of schedule.

How Electric Cars Work: Motors
It has to do with magnetism and the natural interplay between electric fields and magnetic fields. When an electrical circuit closes allowing electrons to move along a wire, those moving electrons generate an electromagnetic field complete with a north and a south pole. When this happens in the presence of another magnetic field—either from a different batch of speeding electrons or from Wile E. Coyote's giant ACME horseshoe magnet, those opposite poles attract, and like poles repel each other.

Electric motors work by mounting one set of magnets or electromagnets to a shaft and another set to a housing surrounding that shaft. By periodically reversing the polarity (swapping the north and south poles) of one set of electromagnets, the motor leverages these attracting and repelling forces to rotate the shaft, thereby converting electricity into torque and ultimately turning the wheels, in a sector where the electric motor market is growing rapidly worldwide. Conversely—as in the case of regenerative braking—these magnetic/electromagnetic forces can transform motion back into electricity.

How Electric Cars Work: AC Or DC?
The electricity supplied to your home arrives as alternating current (AC), and bidirectional charging means EVs can power homes for days as needed, so-called because the north/south or plus/minus polarity of the power changes (alternates) 60 times per second. (That is, in the United States and other countries operating at 110 volts; countries with a 220-volt standard typically use 50-Hz AC.) Direct current (DC) is what goes into and comes out of the + and - poles of every battery. As noted above, motors require alternating current to spin. Without it, the electromagnetic force would simply lock their north and south poles together. It's the cycle of continually switching north and south that keeps a motor spinning.

Today's electric cars are designed to manage both AC and DC energy on board. The battery stores and dispenses DC current, but again, the motor needs AC. When recharging the battery, and with increasing grid coordination enabling flexibility, the energy comes into the onboard charger as AC current during Level 1 and Level 2 charging and as DC high-voltage current on Level 3 "fast chargers." Sophisticated power electronics (which we will not attempt to explain here) handle the multiple onboard AC/DC conversions while stepping the voltage up and down from 100 to 800 volts of charging power to battery/motor system voltages of 350-800 volts to the many vehicle lighting, infotainment, and chassis functions that require 12-48-volt DC electricity.

How Electric Cars Work: What Types Of Motors?
DC Motor (Brushed): Yes, we just said AC makes the motor go around, and these old-style motors that powered early EVs of the 1900s are no different. DC current from the battery is delivered to the rotor windings via spring-loaded "brushes" of carbon or lead that energize spinning contacts connected to wire windings. Every few degrees of rotation, the brushes energize a new set of contacts; this continually reverses the polarity of the electromagnet on the rotor as the motor shaft turns. (This ring of contacts is known as the commutator).

The housing surrounding the rotor's electromagnetic windings typically features permanent magnets. (A "series DC" or so-called "universal motor" may use an electromagnetic stator.) Advantages are low initial cost, high reliability, and ease of motor control. Varying the voltage regulates the motor's speed, while changing the current controls its torque. Disadvantages include a lower lifespan and the cost of maintaining the brushes and contacts. This motor is seldom used in transportation today, save for some Indian railway locomotives.

Brushless DC Motor (BLDC): The brushes and their maintenance are eliminated by moving the permanent magnets to the rotor, placing the electromagnets on the stator (housing), and using an external motor controller to alternately switch the various field windings from plus to minus, thereby generating the rotating magnetic field.

Advantages are a long lifespan, low maintenance, and high efficiency. Disadvantages are higher initial cost and more complicated motor speed controllers that typically require three Hall-effect sensors to get the stator-winding current phased correctly. That switching of the stator windings can result in "torque ripple"—periodic increases and decreases in the delivered torque. This type of motor is popular for smaller vehicles like electric bikes and scooters, and it's used in some ancillary automotive applications like electric power steering assist.

Permanent-Magnet Synchronous Motor (PMSM): Physically, the BLDC and PMSM motors look nearly identical. Both feature permanent magnets on the rotor and field windings in the stator. The key difference is that instead of using DC current and switching various windings on and off periodically to spin the permanent magnets, the PMSM functions on continuous sinusoidal AC current. This means it suffers no torque ripple and needs only one Hall-effect sensor to determine rotor speed and position, so it's more efficient and quieter.

The word "synchronous" indicates the rotor spins at the same speed as the magnetic field in the windings. Its big advantages are its power density and strong starting torque. A main disadvantage of any motor with spinning permanent magnets is that it creates "back electromotive force" (EMF) when not powered at speed, which causes drag and heat that can demagnetize the motor. This motor type also sees some duty in power steering and brake systems, but it has become the motor design of choice in most of today's battery electric and hybrid vehicles.

Note that most permanent-magnet motors of all kinds orient their north-south axis perpendicular to the output shaft. This generates "radial (magnetic) flux." A new class of "axial flux" motors orients the magnets' N-S axes parallel to the shaft, usually on pairs of discs sandwiching stationary stator windings in between. The compact, high-torque axial flux orientation of these so-called "pancake motors" can be applied to either BLDC or PMSM type motors.

AC Induction: For this motor, we toss out the permanent magnets on the rotor (and their increasingly scarce rare earth materials) and keep the AC current flowing through stator windings as in the PMSM motor above.

Standing in for the magnets is a concept Nikola Tesla patented in 1888: As AC current flows through various windings in the stator, the windings generate a rotating field of magnetic flux. As these magnetic lines pass through perpendicular windings on a rotor, they induce an electric current. This then generates another magnetic force that induces the rotor to turn. Because this force is only induced when the magnetic field lines cross the rotor windings, the rotor will experience no torque or force if it rotates at the same (synchronous) speed as the rotating magnetic field.

This means AC induction motors are inherently asynchronous. Rotor speed is controlled by varying the alternating current's frequency. At light loads, the inverter controlling the motor can reduce voltage to reduce magnetic losses and improve efficiency. Depowering an induction motor during cruising when it isn't needed eliminates the drag created by a permanent-magnet motor, while dual-motor EVs using PMSM motors on both axles must always power all motors. Peak efficiency may be slightly greater for BLDC or PMSM designs, but AC induction motors often achieve higher average efficiency. Another small trade-off is slightly lower starting torque than PMSM. The GM EV1 of the mid-1990s and most Teslas have employed AC Induction motors, despite skepticism about an EV revolution in some quarters.

Reluctance Motor: Think of "reluctance" as magnetic resistance: the degree to which an object opposes magnetic flux. A reluctance motor's stator features multiple electromagnet poles—concentrated windings that form highly localized north or south poles. In a switched reluctance motor (SRM), the rotor is made of soft magnetic material such as laminated silicon steel, with multiple projections designed to interact with the stator's poles. The various electromagnet poles are turned on and off in much the same way the field windings in a BLDC motor are. Using an unequal number of stator and rotor poles ensures some poles are aligned (for minimum reluctance), while others are directly in between opposite poles (maximum reluctance). Switching the stator polarity then pulls the rotor around at an asynchronous speed.

A synchronous reluctance motor (SynRM) doesn't rely on this imbalance in the rotor and stator poles. Rather, SynRM motors feature a more distributed winding fed with a sinusoidal AC current as in a PMSM design, with speed regulated by a variable-frequency drive, and an elaborately shaped rotor with voids shaped like magnetic flux lines to optimize reluctance.

The latest trend is to place small permanent magnets (often simpler ferrite ones) in some of these voids to take advantage of both magnetic and reluctance torque while minimizing cost and the back EMF (or counter-electromotive force) high-speed inefficiencies that permanent-magnet motors suffer.

Advantages include lower cost, simplicity, and high efficiency. Disadvantages can include noise and torque ripple (especially for switched reluctance motors). Toyota introduced an internal permanent-magnet synchronous reluctance motor (IPM SynRM) on the Prius, and Tesla now pairs one such motor with an AC induction motor on its Dual Motor models. Tesla also uses IPM SynRM as the single motor for its rear-drive models.

Electric motors may never sing like a small-block or a flat-plane crank Ferrari. But maybe, a decade or so from now, we'll regard the Tesla Plaid powertrain as fondly as we do those engines, even as industry leaders note that mainstream adoption faces hurdles, and every car lover will be able to describe in intimate detail what kind of motors it uses.
 

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