4 European nations to build North Sea wind farms

US Solar Power 2050 Target projects 45% electricity from solar, advancing decarbonization with clean energy, wind, nuclear, hydropower, hydrogen, and scalable energy storage, while modernizing the grid and transmission to cut emissions and create jobs.

Key Points

A goal for solar to supply ~45% of US electricity by 2050, backed by energy storage and other low-carbon generation.

✅ Requires 1,050-1,570 GW solar and matching storage capacity

✅ Utility-scale buildout uses ~10M acres; rooftop 10-20% of capacity

✅ Complemented by wind, nuclear, hydropower, hydrogen, and flexible turbines

President Joe Biden has called for major clean energy investments as a way to curb climate change and generate jobs. On Sept. 8, 2021, the White House released a report produced by the U.S. Department of Energy that found that solar power could generate up to 45% of the U.S. electricity supply by 2050, compared to less than 4% today, with about 3% in 2020 noted by industry observers. The Conversation asked Joshua D. Rhodes, an energy technology and policy researcher at the University of Texas at Austin, what it would take to meet this target.

Why such a heavy focus on solar power? Doesn’t a low-carbon future require many types of clean energy, even though wind and solar could meet about 80% of demand according to some research?
The Energy Department’s Solar Futures Study lays out three future pathways for the U.S. grid: business as usual; decarbonization, meaning a massive shift to low-carbon and carbon-free energy sources; and decarbonization with economy-wide electrification of activities that are powered now by fossil fuels.

It concludes that the latter two scenarios would require approximately 1,050-1,570 gigawatts of solar power, which would meet about 44%-45% of expected electricity demand in 2050, even as renewables approach one-fourth of U.S. generation in the near term. For perspective, one gigawatt of generating capacity is equivalent to about 3.1 million solar panels or 364 large-scale wind turbines.

The rest would come mostly from a mix of other low- or zero-carbon sources, including wind, nuclear, hydropower, biopower, geothermal and combustion turbines run on zero-carbon synthetic fuels such as hydrogen. Energy storage capacity – systems such as large installations of high-capacity batteries – would also expand at roughly the same rate as solar, with record growth in solar and storage anticipated by industry in coming years.

One advantage solar power has over many other low-carbon technologies is that most of the U.S. has lots of sunshine. Wind, hydropower and geothermal resources aren’t so evenly distributed: There are large zones where these resources are poor or nonexistent.

Relying more heavily on region-specific technologies would mean developing them extremely densely where they are most abundant. It also would require building more high-voltage transmission lines to move that energy over long distances, which could increase costs and draw opposition from landowners – a key reason the grid isn't yet 100% renewable according to experts – in many regions.

Is generating 45% of U.S. electricity from solar power by 2050 feasible?
I think it would be technically possible but not easy. It would require an accelerated and sustained deployment far larger than what the U.S. has achieved so far, even as the cost of solar panels has fallen dramatically, and wind, solar and batteries are 82% of the utility-scale pipeline across the country. Some regions have attained this rate of growth, albeit from low starting points and usually not for long periods.

The Solar Futures Study estimates that producing 45% of the nation’s electricity from solar power by 2050 would require deploying about 1,600 gigawatts of solar generation. That’s a 1,450% increase from the 103 gigawatts that are installed in the U.S. today, even as wind and solar trend toward 30% of U.S. electricity in some outlooks. For perspective, there are currently about 1,200 gigawatts of electricity generation capacity of all types on the U.S. power grid.

The report assumes that 10%-20% of this new solar capacity would be deployed on homes and businesses. The rest would be large utility-scale deployments, mostly solar panels, plus some large-scale solar thermal systems that use mirrors to reflect the sun to a central tower.

Assuming that utility-scale solar power requires roughly 8 acres per megawatt, this expansion would require approximately 10.2 million to 11.5 million acres. That’s an area roughly as big as Massachusetts and New Jersey combined, although it’s less than 0.5% of total U.S. land mass.

I think goals like these are worth setting, but are good to reevaluate over time to make sure they represent the most prudent path.

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Canada Electricity Decarbonization Costs indicate challenging greenhouse gas reductions across a fragmented grid, with wind, solar, nuclear, and natural gas tradeoffs, significant GDP impacts, and Net Zero targets constrained by intermittency and limited interties.

Key Points

Costs to cut power CO2 via wind, solar, gas, and nuclear, considering grid limits, intermittency, and GDP impacts.

✅ Alberta model: eliminate coal; add wind, solar, gas; 26-40% CO2 cuts

✅ Nuclear option enables >75% cuts at higher but feasible system costs

✅ National costs 1-2% GDP; reserves, transmission, land, and waste not included

Along with many western developed countries, Canada has pledged to reduce its greenhouse gas emissions by 40–45 percent by 2030 from 2005 emissions levels, and to achieve net-zero emissions by 2050.

This is a huge challenge that, when considered on a global scale, will do little to stop climate change because emissions by developing countries are rising faster than emissions are being reduced in developed countries. Even so, the potential for achieving emissions reduction targets is extremely challenging as there are questions as to how and whether targets can be met and at what cost. Because electricity can be produced from any source of energy, including wind, solar, geothermal, tidal, and any combustible material, climate change policies have focused especially on nations’ electricity grids, and in Canada cleaning up electricity is viewed as critical to meeting climate pledges.

Canada’s electricity grid consists of ten separate provincial grids that are weakly connected by transmission interties to adjacent grids and, in some cases, to electricity systems in the United States. At times, these interties are helpful in addressing small imbalances between electricity supply and demand so as to prevent brownouts or even blackouts, and are a source of export revenue for provinces that have abundant hydroelectricity, such as British Columbia, Manitoba, and Quebec.

Due to generally low intertie capacities between provinces, electricity trade is generally a very small proportion of total generation, though electricity has been a national climate success in recent years. Essentially, provincial grids are stand alone, generating electricity to meet domestic demand (known as load) from the lowest cost local resources.

Because climate change policies have focused on electricity (viz., wind and solar energy, electric vehicles), and Canada will need more electricity to hit net-zero according to the IEA, this study employs information from the Alberta electricity system to provide an estimate of the possible costs of reducing national CO2 emissions related to power generation. The Alberta system serves as an excellent case study for examining the potential for eliminating fossil-fuel generation because of its large coal fleet, favourable solar irradiance, exceptional wind regimes, and potential for utilizing BC’s reservoirs for storage.

Using a model of the Alberta electricity system, we find that it is infeasible to rely solely on renewable sources of energy for 100 percent of power generation—the costs are prohibitive. Under perfect conditions, however, CO2 emissions from the Alberta grid can be reduced by 26 to 40 percent by eliminating coal and replacing it with renewable energy such as wind and solar, and gas, but by more than 75 percent if nuclear power is permitted. The associated costs are estimated to be some $1.4 billion per year to reduce emissions by at most 40 percent, or $1.9 billion annually to reduce emissions by 75 percent or more using nuclear power (an option not considered feasible at this time).

Based on cost estimates from Alberta, and Ontario’s experience with subsidies to renewable energy, and warnings that the switch from fossil fuels to electricity could cost about $1.4 trillion, the costs of relying on changes to electricity generation (essentially eliminating coal and replacing it with renewable energy sources and gas) to reduce national CO2 emissions by about 7.4 percent range from some $16.8 to $33.7 billion annually. This constitutes some 1–2 percent of Canada’s GDP.

The national estimates provided here are conservative, however. They are based on removing coal-fired power from power grids throughout Canada. We could not account for scenarios where the scale of intermittency turned out worse than indicated in our dataset—available wind and solar energy might be lower than indicated by the available data. To take this into account, a reserve market is required, but the costs of operating such a capacity market were not included in the estimates provided in this study. Also ignored are the costs associated with the value of land in other alternative uses, the need for added transmission lines, 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.

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EV Boom Aftershock highlights electric vehicles straining grid capacity as policy accelerates adoption, requiring charging infrastructure, renewable energy storage, and transition models from Tesla, NIO, Toyota, GM, Blink Charging, and Facedrive's Steer subscription.

Key Points

EV Boom Aftershock is the grid and industry strain from rapid EV adoption requiring charging and storage upgrades.

✅ Policy push: fleet electrification, 550k chargers planned

✅ Grid capacity, storage, and charging infrastructure are critical

✅ Bridge models: subscriptions, rideshare, and logistics electrification

2020 ushered in the start of the EV boom, but it could have a frightening aftershock. The world is already seeing some of the incredible triple-digit gains in EV companies like Tesla and Workhorse. And this EV wave is only expected to grow bigger in the days ahead under the Biden administration.  Mentioned in today's commentary includes:  Tesla, Inc., NIO Limited, Toyota Motor Corporation, General Motors Company, Blink Charging Co.

Just a week after inauguration, President Biden reported he plans to replace the entire government fleet with electric vehicles. That's up to 643,000 vehicles turning electric on the government's dime. But Toyota's president, Akio Toyoda, had an ominous prediction for what could lie ahead.

He stated that if EVs are adopted too quickly, we may not have the energy to support them at this point. In fact, he predicted Japan would run out of electricity by summer if they banned all gas-powered vehicles now. He even went as far as to say that if we rush the process of transitioning to EVs all at once, "the current business model of the auto industry is going to collapse."

While the buzz for electric vehicles has only grown over the last year, many often miss this key piece in making such a drastic shift in such a short period. And although it's expected to create plenty of demand for solar, wind, nuclear, and geothermal energy sources…

At this point in the game, they are still too expensive and lack the storage capacity we'd need for those to be the final solution. That's why companies bridging the gap to the EV world are thriving.

Facedrive, a company known for its "people and planet first" approach, has seen incredible success over the last year, for example. They recently acquired EV subscription company, Steer, from the largest clean energy producer in the United States. Steer's subscription model for EV cars is putting a major twist on the traditional car ownership model. So instead of everyone going out and buying their own EV, they can borrow one as-needed instead.

With Facedrive's acquisition of Steer, customers pay a simple monthly fee like with Netflix, and they get access to a fleet of EVs at their disposal.

Over the last year, big moves like this have helped Facedrive sign a number of important partnerships and deals including government agencies, A-list celebrities, and major multinational corporations. And they've even managed to grow their business throughout the United States and Canada during a time when ridesharing as an industry suffered during global lockdowns.

Smartest in the World Making Bold Predictions

While Toyota's president made a dark prediction about where we could be headed, he's not alone in being concerned. Elon Musk expressed his own concerns about the issue recently as well.

In an interview in December, he said that the world's electricity consumption would likely double once EVs become the norm. And that's only accounting for this mass adoption in electric vehicles.

The situation could become even more pressing as the rest of our lives grow increasingly digital too, sucking up more electricity in the process. With the "internet of things" creating smart cities and smart homes, the demand for electricity will only go up as everything from Peloton bikes to Nest thermostats are now connected by the internet.

With thousands of cars on the roads during morning and evening commutes, it's not hard to imagine times where we simply wouldn't have enough grid capacity to charge all EVs that need it at once.

But in the meantime, Facedrive's moves are putting them squarely in position to smooth out the transition. And in addition to the monthly membership model used with Steer, they're helping keep the number of cars on the road down through their signature ridesharing service.

Their model is simple. When customers hail a ride, they have the choice to ride in an electric vehicle or a standard gas-powered car. After they get to their destination, the Facedrive algorithm sets aside a portion of the fare to plant trees, offsetting the carbon footprint from the ride. In other words, customers ride, they plant a tree.

Through next-gen technology and partnerships, they're giving their customers the option to make a more eco-friendly choice if they choose. Plus, Facedrive has added a booming food delivery service, which has expanded at a record pace while folks were stuck at home during global lockdowns.

They're now delivering over 4,100 orders per day on average. And after growing to 19 major cities, they plan to expand to more cities throughout the U.S. and Canada soon. It's this kind of innovative thinking that has many so optimistic about the opportunities that lie ahead.

Who Will Win In The EV Boom?

Elon Musk warned that, like with the boom in smartphones, we're not likely to see the EV revolution all happen at once, and industry leaders still see mainstream hurdles ahead for broad adoption. Because just like with smartphones, you can't replace them all at once. But it's undeniable that the movement is growing at a remarkable pace, with many arguing it has reached an inflection point already in several segments today.

Even under an administration that was not supportive of climate change and green initiatives, the EV markets have soared throughout 2020, and U.S. EV sales are surging into 2024 as well across segments.

Tesla was one of the biggest market stories of the year, locking in over 700% gains on its way to becoming one of the largest companies on the S&P 500. And experts are expecting to see massive spending on the infrastructure needed for EVs under the Biden administration too.

In addition to his vow to spend more on clean energy research, President Biden also reported plans to build out 550,000 EV charging stations across the country. With the growth we've seen in this area already, it's also caused shares for companies like Plug Power to soar over 1,000% in 2020. And Facedrive has been sharing in this success too, with incredible gains of 834% over the last year.

Facedrive hasn't been the only company riding the EV wave, however.  Tesla (TSLA) was among the biggest market stories of 2020 with incredible gains of over 700%. This helped them become one of the highest-valued stocks in the United States with other Big Tech giants. It is now the most valuable car maker "of all time". It is now worth almost $800 billion.

After a much-touted Battery Day event and expectations of Musk developing a "Million Mile Battery" in the near future, Tesla recently joined the S&P 500.

Billionaire Elon Musk had his eye on this trend far before the hype started building. He released the first Tesla Roadster back in 2008, making electric vehicles cool when people were still snubbing their noses at the first-generation EVs. Since then, Tesla's stock has skyrocketed by over 14,000%. But while Tesla's EV threat to the industry is clear, the competition is heating up in China's EV market right now as rivals scale.

Nio (NIO) is Tesla's biggest competitor, dominating the Chinese EV markets. After going public in 2018, it's been on a tear, producing vehicles with record-breaking range. They recently unveiled their first electric sedan with a longer range battery, which sent shares surging in early January.

Nio's current performance is a far cry from just one year ago In fact, many shareholders were ready to write off their losses and give up on the company. But China's answer to Tesla's dominance powered on, eclipsed estimates, and most importantly, kept its balance sheet in line. And it's paid off. In a big way. The company has seen its share price soar from $3.24 at the start of 2020 to a high of $61 this month, representing a massive 1600% returns for investors who held strong. 

By NIO's fourth quarter report in October, the company announced that its sales had more-than doubled, projecting even greater sales in 2021. The EV up-and-comer has shocked investors and pulled itself back after its rumored potential bankruptcy in 2019, and if this year shows investors anything, it's that its CEO William Li is as skilled and ambitious as anyone in the business.

Toyota Motors (TM) is a massive international car producer who hasn't ignored the transition to greener transportation. In fact, the Toyota Prius was one of the first hybrids to hit the road in a big way. While the legacy hybrid vehicle has been the butt of many jokes throughout the years, the car has been a major success, and more importantly, it helped spur the adoption of greener vehicles for years to come.

And just because its Prius hasn't exactly aged as well as some green competitors, Toyota hasn't left the green power race yet. Just a few days ago, actually, the giant automaker announced that three new electric vehicles will be coming to United States markets soon.

Toyota has a major hold over U.S. markets at the moment. In fact, it maintains a 75% share of total fuel cell vehicles and a 64% share in hybrid and plug-in vehicles. And now it's looking to capture a greater share of electric vehicles, as well.

General Motors (GM) is one of the legacy automakers benefiting from a shift from gas-powered to EV technology. Even with the downfall of Detroit, GM has persisted, and that's due in large part to its ability to adapt. In fact, GM's dive into alternative fuels began way back in 1966 when it produced the world's first ever hydrogen-powered van for testing. And it has not stopped innovating, either.

With the news of GM's new business unit, BrightDrop, they plan to sell electric vans and services to commercial delivery companies, disrupting the market for delivery logistics. This is a huge move as delivery sales have absolutely exploded during the COVID-19 pandemic, and are projected to grow even further over the coming years.

And in January 2021, the giant automaker announced that it will discontinue production of all gas-powered vehicles, including hybrids, by 2035. This is a key factor in its commitment to become carbon-net zero by 2040.  The move will likely sit well with shareholders which are increasingly pushing for companies to clean up their act.

Blink Charging (BLNK) is building an EV charging network that may be small right now, but it's got explosive growth potential that is as big as the EV market itself. This stock is on a major tear and all that cash flowing into it right now gives Blink the superpower to acquire and expand. 

A wave of new deals, including a collaboration with EnerSys and another with Envoy Technologies to deploy electric vehicles and charging stations adds further support to the bullish case for Blink.

Michael D. Farkas, Founder, CEO and Executive Chairman of Blink noted, "This is an exciting collaboration with EnerSys because it combines the industry-leading technologies of our two companies to provide user-friendly, high powered, next-generation charging alternatives. We are continuously innovating our product offerings to provide more efficient and convenient charging options to the growing community of EV drivers."

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Electrified Trucking Grid Integration explores vehicle-to-grid (V2G) strategies where rolling batteries backfeed power during peak demand, optimizing charging infrastructure, time-of-use pricing, and IESO market operations for Ontario shippers like Nature Fresh Farms.

Key Points

An approach using V2G-enabled electric trucks to support the grid, cut peak costs, and add revenue streams.

✅ Models charging sites, timing, and local grid impacts.

✅ Evaluates V2G backfeed economics and IESO pricing.

✅ Uses Nature Fresh Farms data for logistics and energy.

A University of Windsor project will study whether an electrified trucking industry might not only deliver the goods, but help keep the lights on with the timely off-loading of excess electrons from their powerful batteries via vehicle-to-grid approaches now emerging.

The two-year study is being overseen by Environmental Energy Institute director Rupp Carriveau and associate professor Hanna Moah of the Cross-Border Institute in conjunction with the Leamington-based greenhouse grower Nature Fresh Farms.

“The study will look at what happens if we electrified the transport truck fleet in Ontario to different degrees, considering the power demand for truck fleets that would result,” Carriveau said.

“Where trucks would be charging and how that will affect the electricity grid grid coordination in those locations at specific times. We’ll be able to identify peak times on the demand side.

“On the other side, we have to recognize these are rolling batteries. They may be able to backfeed the grid, sell electricity back to prop the grid up in locations it wasn’t able to in the past.”

The national research organization Mathematics of International Technology and Complex Systems (Mitacs) is funding the $160,000 study, and the Independent Electricity Systems Operator, a Crown corporation responsible for operating Ontario’s electricity market, amid an electricity supply crunch that is boosting storage efforts, is also offering support for the project.

Because of the varying electricity prices in the province based on usage, peak demand and even time of year, Carriveau said there could be times where draining off excess truck battery power will be cheaper than the grid, and vehicle-to-building charging models show how those savings can be realized.

“It could offer the truck owner another revenue stream from his asset, and businesses a cheaper electricity alternative in certain circumstances,” he said.

The local greenhouse industry was a natural fit for the study, said Carriveau, based on the amount of work the university does with the sector along with the fact it is both a large consumer and producer of electricity.

The study will be based on assumptions for electric truck capacity and performance because the low number of such vehicles currently on the road, though large electric bus fleets offer operational insights.

How will an electrified trucking industry affect Ontario’s electricity grid? University of Windsor engineering professor Rupp Carriveau is part of a new study on trucks being used to help deliver electricity as well as their products around Ontario. He is shown on campus on Tuesday, July 6, 2021.

How will an electrified trucking industry affect Ontario’s electricity grid? University of Windsor engineering professor Rupp Carriveau is part of a new study on trucks being used to help deliver electricity as well as their products around Ontario. He is shown on campus on Tuesday, July 6, 2021.

Nature Fresh Farms will supply all its data on power use, logistics, utility costs and shipping schedules to determine if switching to an electrified fleet makes sense for the company.

“As an innovative company, we are always thinking, ‘What is next?’, whether its developments in product varieties, technology or sustainability,” said company CEO Peter Quiring. “Green transportation is the next big focus.

“We were given the opportunity to work closely on this project and offer our operations as a case study to see how we can find feasible alternatives, not only for Nature Fresh Farms or even for companies in agriculture, but for every industry that relies on the transportation of their goods.”

Currently, Nature Fresh Farms doesn’t have any electrified trucks. Carriveau said the second phase of the study might actually involve an electric truck in a pilot project.

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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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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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