Renewables became the second-most prevalent U.S. electricity source in 2020

Canada Solar Capacity Outlook 2022-2050 projects 500 MW new PV in 2022 and 35 GW by 2050, driven by renewables policy, grid parity, NREL analysis, IEA-PVPS data, and competitive utility-scale photovoltaic costs.

Key Points

An evidence-based forecast of Canadian PV additions to 35 GW by 2050, reflecting policy, costs, and grid parity trends.

✅ 500 MW PV expected in 2022; cumulative capacity near 5 GW

✅ NREL outlook sees 35 GW by 2050 on cost competitiveness

✅ Policy shifts, ITCs, coal retirements accelerate solar uptake

Canada is set to install 500 MW of new solar in 2022, bringing its total capacity to about 5 GW, according to data from Canmet Energy, even as the Netherlands outpaces Canada in solar power generation. The country is expected to hit 35 GW of total solar capacity by 2050.

Canada’s cumulative solar capacity is set to hit 5 GW by the end of this year, according to figures from the federal government’s Canmet Energy lab. The country is expected to add around 500 MW of new solar capacity, from 944 MW last year, according to the International Energy Agency Photovoltaic Power Systems Programme (IEA-PVPS), which recently published a report on PV applications in Canada, even as solar demand lags in Canada.

“If we look at the recent averages, Canada has installed around 500 MW annually. I expect in 2022 it will be at least 500 MW,” said Yves Poissant, research manager at Canmet Energy. “Last year it was 944 MW, mainly because of a 465 MW centralized PV power plant installed in Alberta, where the Prairie Provinces are expected to lead national renewable growth.”

The US National Renewable Energy Laboratory (NREL) studied renewables integration and concluded that Canada’s cumulative solar capacity will increase sevenfold to 35 GW by 2050, driven by cost competitiveness and that zero-emissions by 2035 is achievable according to complementary studies.

Canada now produces 80% of its electricity from power sources other than oil. Hydroelectricity leads the mix at 60%, followed by nuclear at 15%, wind at 7%, gas and coal at 7%, and PV at just 1%. While the government aims to increase the share of green electricity to 90% by 2030 and 100% by 2050, zero-emission electricity by 2035 is considered practical and profitable, yet it has not set any specific goals for PV. Each Canadian province and territory is left to determine its own targets.

“Without comprehensive pan-Canadian policy framework with annual capacity targets, PV installation in the coming years will likely continue to be highly variable across the provinces and territories, especially after Ontario scrapped a clean energy program, which scaled back growth projections. Further policies mechanisms are needed to allow PV to reach its full potential,” the IEA-PVPS said.

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Canada recently introduced investment tax credits for renewables to compete with the United States, but it is still far from being a solar powerhouse, with some experts calling it a solar laggard today. That said, the landscape has started to change in the past five years.

“Some laws have been put in place to retire coal plants by 2025. That led to new opportunities to install capacity,” said Poissant. “We expect the newly installed capacity will consist mostly of wind, but also solar.”

The cost of solar has become more competitive and the residential sector is now close to grid parity, according to Poissant. For utility-scale projects, old hydroelectric dams are still considerably cheaper than solar, but newly built installations are now more expensive than solar.

“Starting 2030, solar PV will be cost competitive compared to wind,” Poissant said.

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Condo EV charging retrofits face strata approval thresholds, installation costs, and limited electrical capacity, but government rebates, subsidies, and smart billing systems can improve ROI, property value, and feasibility amid electrician shortages and infrastructure constraints.

Key Points

Condo EV charging retrofits equip multiunit parking with EV chargers, balancing costs, bylaws, capacity, and rebates.

✅ Requires owner approval (e.g., 75% in B.C.) and clear bylaws

✅ Leverage rebates, subsidies, and load management to cut costs

✅ Plan billing, capacity, and phased installation to increase ROI

Retrofitting an existing multiunit residential building with electric vehicle charging stations is a complex and costly exercise, as high-rise EV charging challenges in MURBs demonstrate, even after subsidies, but the biggest hurdle to adoption may be getting enough condo owners on board.

British Columbia, for example, offers a range of provincial government subsidies to help condo corporations (referred to in B.C. as stratas) with everything from the initial research to installing the chargers. But according to provincial strata law, three-quarters of owners must support the plan before it is implemented, though new strata EV legislation could make approvals easier in some jurisdictions.

“The largest challenge is getting that 75-per-cent majority approval to go ahead,” says EV charging specialist Patrick Breuer with ChargeFwd Ltd., a Vancouver-based sustainable transport consultancy.

Chris Brunner, a strata president in Vancouver, recently upgraded all the building’s parking stalls for EV charging. His biggest challenge was getting the strata’s investment owners, who don’t live in the building and were not interested in spending money, to support the project.

“We had to sell it in two ways,” Mr. Brunner says. “First, that there’s going to be a return on investment, including vehicle-to-building benefits that support savings and grid stability, and second, that there will come a time when this will be required. And if we do it now, taking advantage of the generous rebates and avoiding price increases for expertise and materials, we’ll be ahead of the curve.”

Once the owners have voted in favour, the condo board can begin the planning process and start looking for rebates. The B.C. government will provide a rebate of up to 75 per cent for the consulting phase, with additional provincial rebates available through current programs. It’s referred to as an “EV Ready” plan, which is a professionally prepared document that describes how to implement EV charging fairly, and estimates its cost.

Once a condo has completed the EV Ready plan, it becomes eligible for other rebates, such as the EV Ready Infrastructure subsidy, which will bring power to each individual parking stall through an energized outlet. This is rebated at 50 per cent of expenses, up to $600 a stall.

There are further rebates of up to 75 per cent for installing the charging stations themselves, and B.C. charging rebates extend to home and workplace programs, too. The program is administered by BC Hydro, a Crown corporation that receives funding in annual increments. “Right now, it’s funded until March 31, 2023,” Mr. Breuer says.

“Realtors are valuing [individual charging stations] from $2,000 to $10,000,” he said. The demand for installing EV chargers in buildings has grown to such an extent that it’s hard to find qualified electricians, Mr. Breuer says.

However, even with subsidies, there are some buildings where it doesn’t make financial sense to retrofit them. “If you have to core through thin floors or there’s a big parkade with a large voltage drop, it isn’t financially viable,” Mr. Breuer says. “We do a lot of EV Ready plans, but not all the projects can go ahead.”

For many people, it’s resistance to the unknown that is preventing them from voting for the retrofit, according to Carter Li of Toronto-based Swtch Energy Inc., which provides charging in high-density urban settings. It has done retrofits on 200 multiunit residential buildings in the Toronto area, and Calgary condo charging efforts show similar momentum in other cities, too. “They’re worried about paying for someone else’s electricity,” he says. Selling owners on the idea requires educating them about how the billing will work, maximizing electrical capacity to keep costs down, using government subsidies and the anticipated boost in property value.

Ontario currently does not provide any subsidies for retrofitting condos for EV charging. However, there is a stipulation under the Condominium Act that if owners request EV charging be installed and provide a condo board with sufficient documentation, an assessment will be conducted.

When Jeremy Benning was on the board of his Toronto condo in 2018, a few residents inquired about installing EV charging. A committee of owners did the legwork, and found a company that could do the infrastructure installation as well as set up accounts for individual billing purposes. Residents were surveyed a number of times before going ahead with the installation.

Mr. Benning estimates it cost about $40,000 to install two electrical subpanels to accommodate EV chargers in 20 parking spaces. Although the condo corporation paid the money up front out of its operating budget, everyone who ordered a charger will pay back their share over time. Many who do not even own an EV have opted to add a valuable frill to their unit.

The board considered applying for a subsidy from Natural Resources Canada, but it would require a public charger in the visitor parking lot. “The rebate wasn’t enough to pay for the cost of putting in that charging station,” Mr. Benning says. “Also, you have to maintain it, and what if it gets vandalized? It wasn’t worth it.”

Quebec’s Roulez Vert (Ride Green) program offers extensive provincial rebates and incentives for retrofitting condo buildings. If a single condo owner wants to install an EV charger, the government will refund up to 50 per cent of the installation cost or up to $5,000, whichever is less.

Otherwise, a property manager can qualify for a maximum of $25,000 a year to retrofit a building and can sometimes complete the work in stages. “They may do the first installation in one year, and then continue the next year,” says Léo Viger-Bernard of Recharge Véhicule Électrique (RVE). Recently, the Quebec government confirmed this program will run until 2027.

RVE consults with condo corporations, operates an online platform (murby.com) with resources for building owners, and sells a demand charge controller (DCC), which is an electric vehicle energy management system. The DCC allows an electrician to plug the EV charger directly into the electrical infrastructure of a single condo or apartment unit. Not only does this reduce extra wiring, but it also monitors the electrical consumption in each unit, only powering the charging station when there’s available electricity. Billing is assigned to the actual unit’s electricity bill.

Currently there are about 12,000 DCC units installed in retrofitted buildings across Canada, some that are 40 or 50 years old. “It’s not a question of age; it’s more the location of the electric meters,” Mr. Viger-Bernard says. The DCC can be installed either on the roof or on different floors.

According to Michael Wilk, president of Montreal-based Wilkar Property Management Inc., the biggest barrier is getting condo owners to understand the necessity of doing a retrofit now, as opposed to waiting. He uses price increases to try to convince them.

“Right now, the cost of doing a retrofit is 35 per cent more than it was two years ago,” he says. “If you wait another two years, we can only anticipate it’s going to be 35 per cent higher because of the rising cost of labour, parts and equipment.”

In Nova Scotia, Marc MacDonald of Spark Power Corp. installed an EV charger with a DCC unit at a condo near Halifax about a year ago. “They only had space in their electrical room to add a device for up to 10 EV chargers,” he says. The condo board was hesitant, demanding a great deal of information. “They were concerned about everyone wanting an EV charger.”

Now that Nova Scotia has introduced a program for rebates and incentives to install EV chargers in condos, on-street sites and more, Mr. MacDonald anticipates demand will increase, though Atlantic EV adoption still lags the national average. “But they’ll have to settle with reality. Not everyone can have an EV charger if the building can’t accommodate it.”

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Inflation Reduction Act Clean Energy drives EV adoption and renewable power, but grid interconnection, permitting, and supply chain bottlenecks slow wind, solar, and offshore projects, risking emissions targets despite domestic manufacturing growth and tax incentives.

Key Points

An IRA push to scale EVs and renewables, meeting EV goals but lagging wind and solar amid grid and permitting delays.

✅ EV sales up 50%, 9.2% of 2023 new cars; growth may moderate.

✅ 32.3 GW added, below 46-79 GW/year needed for climate targets.

✅ Grid, permitting, and supply chain delays bottleneck wind and solar.

A year and a half following President Biden's enactment of an ambitious climate change bill, the landscape of the United States' clean energy transition, shaped by 2021 electricity lessons, presents a mix of successes and challenges. A recent study by a consortium of research organizations highlights that while electric vehicle (EV) sales have surged, aligning with the law's projections, the expansion of renewable energy sources like wind and solar has encountered significant hurdles.

The legislation, known as the Inflation Reduction Act, aimed for a dual thrust in America's climate strategy: boosting EV adoption, alongside EPA emission limits, and significantly increasing the generation of electricity from renewable resources. The Act, passed in 2022, was anticipated to propel the United States toward reducing its greenhouse gas emissions by approximately 40 percent from 2005 levels by the end of this decade, backed by extensive financial incentives for clean energy advancements.

Electric vehicle sales have indeed seen a remarkable uptick, with a more than 50 percent increase over the past year, as EV sales surge into 2024 across the market, culminating in EVs comprising 9.2 percent of all new car sales in the United States in 2023. This growth trajectory met the upper range of analysts' predictions post-law enactment, signaling a strong start toward achieving the Act's emission reduction targets.

However, the EV market faces uncertainties regarding the sustainability of this rapid growth. The initial surge in sales was largely driven by early adopters, and the market now confronts challenges such as high prices and limited charging infrastructure, while EVs still trail gas cars in overall market share. Despite these concerns, projections suggest that even a slowdown to 30-40 percent growth in EV sales for 2024 would align with the law's emission goals.

The renewable energy sector's progress is less straightforward. Despite achieving a record addition of 32.3 gigawatts of clean electricity capacity in the past year, the pace falls short of the projected 46 to 79 gigawatts needed annually to meet the United States' climate objectives. While there is potential for about 60 gigawatts of projects in the pipeline for this year, not all are expected to materialize on schedule, indicating a lag in the deployment of new renewable energy sources.

Logistical challenges are a significant barrier to scaling up renewable energy, especially as EV-driven electricity demand rises in the coming years. Lengthy grid connection processes, permitting delays, and local opposition hinder wind and solar project developments. Moreover, ambitious plans for offshore wind farms are hampered by supply chain issues and regulatory constraints.

To achieve the Inflation Reduction Act's ambitious targets, the United States needs to add 70 to 126 gigawatts of renewable capacity annually from 2025 to 2030—a formidable task given the current logistical and regulatory bottlenecks. The analysis underscores the urgency of addressing these non-cost barriers to unlock the full potential of the law's clean energy and emissions reduction ambitions.

In addition to promoting clean energy generation and EV adoption, the Inflation Reduction Act has spurred domestic manufacturing of clean energy technologies. With $44 billion invested in U.S. clean-energy manufacturing last year, this aspect of the law has seen considerable success, and permanent clean energy tax credits are being debated to sustain momentum, demonstrating the Act's capacity to drive economic and industrial transformation.

The law's impact extends to emerging clean energy technologies, offering tax incentives for advanced nuclear reactors, renewable hydrogen production, and carbon capture and storage projects. While these initiatives hold promise for further emissions reductions, their development and deployment are still in the early stages, with tangible outcomes expected in the longer term.

While the Inflation Reduction Act has catalyzed significant strides in certain areas of the United States' clean energy transition, including an EV inflection point in adoption trends, it faces substantial hurdles in fully realizing its objectives. Overcoming logistical, regulatory, and market challenges will be crucial for the nation to stay on course toward its ambitious climate goals, underscoring the need for continued innovation, investment, and policy refinement in the journey toward a sustainable energy future.

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UK Petrol Shortages Drive EV Adoption as fuel crisis spurs electric vehicles, plug-in car demand, home charging, lower running costs, zero-emission mobility, ULEZ compliance, accelerating the shift from diesel to battery EVs.

Key Points

Fuel shortages push drivers to EVs, boosting inquiries and sales while highlighting the convenience of home charging.

✅ Surge in EV dealer inquiries and test drives

✅ Home charging avoids queues and fuel shortages

✅ Policy signals: ULEZ expansion, 2030 ICE ban

Sellers of plug-in vehicles say petrol shortages are driving people to adopt the new technology as the age of electric cars accelerates worldwide.

As petrol stations in parts of the UK started running out of fuel on Friday, business at Martin Miller’s electric car dealership in Guildford, Surrey, started soaring.

After what ended up being his company EV Experts busiest day ever, interest does not appear to be dying down. This week the diary is booked up with test drives and the business is low on stock amid supply constraints.

“People buy electric cars for environmental reasons, for cost-saving reasons and because the technology’s great, even though higher upfront prices remain a concern,” he said. “But Friday was one of those moments where people said, ‘Do you know what, this is a sign that we need to go electric’.”

While scenes of chaos play out at petrol stations across the country amid shortages, for many electric vehicle (EV) dealers the fuel crisis has led to an unexpected surge in inquiries and sales, even as some question an electric-car revolution narrative today.

EVA England, a non-profit representing new and prospective EV drivers, reports a rise in electric car inquiries and in interest at EV dealers, particularly in the last week.

“Saturday was bonkers but Friday even surpassed that, it was very strange,” said Miller, who founded his company four years ago. “I’ve now got trade-in cars with no petrol to move them.”

Along with existing factors such as the expansion of London’s ultra-low emission zone, the fuel crisis has proved to be another trigger point, he said. “People were using it as ‘this is the moment where I’m not going to put this off any longer’.”

The EV market is no longer the preserve of innovators and early adopters, he said, with the most popular models the Nissan Leaf, Volkswagen ID 3 and Jaguar I-Pace.

Ben Strzalko, the owner of Electric Cars UK in Leyland, Lancashire, said that as a small business it would take a few months to feel the knock-on effect of the fuel crisis on sales.

But every time there are problems with petrol or diesel, he said they acted as “one more tick for people making that transition to electric cars”.

He said “a lot of electric car owners will be chuffed to bits this last week” being able to plug in their cars at home. And as an EV driver himself, he admitted feeling a little smug as he drove past queues of 20 cars outside petrol stations over the weekend in his Tesla.

Matt Cleevely, the owner of Cleevely Electric Vehicles in Cheltenham, Gloucestershire, which specialises in used EVs, had a surge of inquiries over the weekend and on Monday morning from customers citing the fuel crisis as a reason for switching to electric.

He expects enthusiasm to continue rising, with petrol shortages adding “fuel to the fire”.

Although he feels sorry for non-EV drivers who have been unable to get fuel, he said as an electric car owner it was “very nice” not to have to worry about where to get petrol at the weekend.

“It’s very convenient that we’ve been able to just fuel up on our driveway. It’s one of the biggest pros of having an electric vehicle.”

The National Franchised Dealers Association also said multiple dealers have reported a spike in EV enquiries since the start of the crisis.

The Society of Motor Manufacturers and Traders reported “bumper growth” in the sale of plug-in cars in July, reflecting broader global market growth in recent years, with battery electric vehicles comprising 9% of sales. Plug-in hybrids accounted for 8% of sales and hybrid electric vehicles nearly 12%. Also in July, more electric vehicles were registered than diesel for the second consecutive month.

The UK has pledged to ban the sale of new petrol and diesel cars by 2030 and of new hybrids by 2035, a timeline that aligns with expectations that within a decade most driving could be electric.

Warren Philips, the volunteer communities director at EVA England, said the tipping point for EVs had already been reached but the fuel crisis “underlines how electric cars could work for the majority of people”.

He added: “The interest is already there, this just adds to it. And going forward with things like Cop26, with the climate crisis, with the cost of fuel probably going to rise … people will start looking at electric cars where you just skip that entire step.”

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Global Renewable Capacity Additions 2023 surge on policy momentum, high fossil prices, and energy security, with solar PV and wind leading growth as grids expand and manufacturing scales across China, Europe, India, and the US.

Key Points

Record solar PV and wind growth from policy and energy security, adding 440+ GW toward 4,500 GW total capacity in 2024.

✅ Solar PV to supply two-thirds of additions; rooftop demand rising.

✅ Wind rebounds ~70% as delayed projects complete in China, EU, US.

✅ Grid upgrades and better permitting, auctions key for 2024 growth.

Global additions of renewable power capacity are expected to jump by a third this year as growing policy momentum, higher fossil fuel prices and energy security concerns drive strong deployment of solar PV and wind power, building on a record year for renewables in 2016, according to the latest update from the International Energy Agency.

The growth is set to continue next year with the world’s total renewable electricity capacity rising to 4 500 gigawatts (GW), equal to the total power output of China and the United States combined, and in the United States wind power has surged in the electricity mix, says the IEA’s new Renewable Energy Market Update, which was published today.

Global renewable capacity additions are set to soar by 107 gigawatts (GW), the largest absolute increase ever, to more than 440 GW in 2023. The dynamic expansion is taking place across the world’s major markets. Renewables are at the forefront of Europe’s response to the energy crisis, accelerating their growth there. New policy measures are also helping drive significant increases in the United States, where solar and wind growth remains strong, and India over the next two years. China, meanwhile, is consolidating its leading position and is set to account for almost 55% of global additions of renewable power capacity in both 2023 and 2024.

“Solar and wind are leading the rapid expansion of the new global energy economy. This year, the world is set to add a record-breaking amount of renewables to electricity systems – more than the total power capacity of Germany and Spain combined,” said IEA Executive Director Fatih Birol. “The global energy crisis has shown renewables are critical for making energy supplies not just cleaner but also more secure and affordable – and governments are responding with efforts to deploy them faster. But achieving stronger growth means addressing some key challenges. Policies need to adapt to changing market conditions, and we need to upgrade and expand power grids to ensure we can take full advantage of solar and wind’s huge potential.”

Solar PV additions will account for two-thirds of this year’s increase in renewable power capacity and are expected to keep growing in 2024, according to the new report. The expansion of large-scale solar PV plants is being accompanied by the growth of smaller systems. Higher electricity prices are stimulating faster growth of rooftop solar PV, which is empowering consumers to slash their energy bills, and in the United States renewables' share is projected to approach one-fourth of electricity generation.

At the same time, manufacturing capacity for all solar PV production segments is expected to more than double to 1 000 GW by 2024, led by China's solar PV growth and increasing supply diversification in the United States, where wind, solar and battery projects dominate the 2023 pipeline, India and Europe. Based on those trends, the world will have enough solar PV manufacturing capacity in 2030 to comfortably meet the level of annual demand envisaged in the IEA’s Net Zero Emissions by 2050 Scenario.

Wind power additions are forecast to rebound sharply in 2023 growing by almost 70% year-on-year after a difficult couple of years in which growth was slugging, even as wind power still grew despite Covid-19 challenges. The faster growth is mainly due to the completion of projects that had been delayed by Covid-19 restrictions in China and by supply chain issues in Europe and the United States. However, further growth in 2024 will depend on whether governments can provide greater policy support to address challenges in terms of permitting and auction design. In contrast to solar PV, wind turbine supply chains are not growing fast enough to match accelerating demand over the medium-term. This is mainly due to rising commodity prices and supply chain challenges, which are reducing the profitability of manufacturers.

The forecast for renewable capacity additions in Europe has been revised upwards by 40% from before Russia’s invasion of Ukraine, which led many countries to boost solar and wind uptake to reduce their reliance on Russian natural gas. The growth is driven by high electricity prices that have made small-scale rooftop solar PV systems more financially attractive and by increased policy support in key European markets, especially in Germany, Italy and the Netherlands.

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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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