Manitoba has clean energy to help neighboring provinces

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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Britain Wind Generation Record underscores onshore and offshore wind momentum, as National Grid ESO reported 20.91 GW, boosting zero-carbon electricity, renewables share, and grid stability amid milder weather, falling gas prices, and net zero goals.

Key Points

The Britain wind generation record is 20.91 GW, set on 30 Dec, driven by onshore and offshore turbines.

✅ Set on 30 Dec 2022 with peak output of 20.91 GW.

✅ Zero-carbon sources hit 87.2% of grid supply.

✅ Driven by onshore and offshore wind; ESO reported stability.

Britain has set a new record for wind generation as power from onshore and offshore turbines helped boost clean energy supplies late last year.

National Grid’s electricity system operator (ESO), which handles Great Britain’s grid operations, said that a new record for wind generation was set on 30 December, when 20.91 gigawatts (GW) were produced by turbines.

This represented the third time Britain’s fleet of wind turbines set new generation records in 2022. In May, National Grid had to ask some turbines in the west of Scotland to shut down, as the network was unable to store such a large amount of electricity when a then record 19.9GW of power was produced – enough to boil 3.5m kettles.

The ESO said a new record was also set for the share of electricity on the grid coming from zero-carbon sources – renewables and nuclear – which supplied 87.2% of total power. These sources have accounted for about 55% to 59% of power over the past couple of years.

The surge in wind generation represents a remarkable reversal in fortunes as a cold snap that enveloped Britain and Europe quickly turned to milder weather.

Power prices had soared as the freezing weather forced Britons to increase their heating use, pushing up demand for energy despite high bills.

The cold weather came with a period of low wind, reducing the production of Britain’s windfarms to close to zero.

Emergency coal-fired power units at Drax in North Yorkshire were put on standby but ultimately not used, while gas-fired generation accounted for nearly 60% of the UK’s power output at times.

However, milder weather in the UK and Europe in recent days has led to a reduction in demand from consumers and a fall in wholesale gas prices. It has also reduced the risk of power cuts this winter, which National Grid had warned could be a possibility.

Wind generation is increasingly leading the power mix in Britain and is seen as a crucial part of Britain’s move towards net zero. The prime minister, Rishi Sunak, is expected to overturn a moratorium on new onshore wind projects with a consultation on the matter due to run until March.

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Tesla Battery Day Innovations detail larger cylindrical EV cells with higher energy density, greater power, longer range, cobalt-free chemistry, automated manufacturing, battery recycling, and lower cost per kWh to enable an affordable electric car.

Key Points

Tesla Battery Day innovations are new EV cells and methods to cut costs, extend range, and scale production.

✅ Larger cylindrical cells: 5x energy, 6x power, 16% more range

✅ Automation and recycling to cut battery cost per kWh

✅ Near-zero cobalt chemistry, in-house cell factories worldwide

Elon Musk described a new generation of electric vehicle batteries that will be more powerful, longer lasting, and half as expensive as the company’s current cells at Tesla’s “Battery Day”.

Tesla’s new larger cylindrical cells will provide five times more energy, six times more power and 16% greater driving range, Musk said, adding that full production is about three years away.

“We do not have an affordable car. That’s something we will have in the future. But we’ve got to get the cost of batteries down,” Musk said.

To help reduce cost, Musk said Tesla planned to recycle battery cells at its Nevada “gigafactory,” while reducing cobalt – one of the most expensive battery materials – to virtually zero. It also plans to manufacture its own battery cells at several highly automated factories around the world.

The automaker plans to produce the new cells via a highly automated, continuous-motion assembly process, according to Drew Baglino, Tesla senior vice-president of powertrain and energy engineering, a contrast with GM and Ford battery strategies in the broader market today.

Speaking at the event, during which Musk outlined plans to cut costs and reiterated a huge future for Tesla's energy business during the presentation, the CEO acknowledged that Tesla does not have its new battery design and manufacturing process fully complete.

The automaker’s shares slipped as Musk forecast the change could take three years. Tesla has frequently missed production targets.

Tesla expects to eventually be able to build as many as 20m electric vehicles a year, aligning with within-a-decade EV adoption outlooks cited by analysts. This year, the entire auto industry expects to deliver 80m cars globally.

At the opening of the event, which drew over 270,000 online viewers, Musk walked on stage as about 240 shareholders – each sitting in a Tesla Model 3 in the company parking lot – honked their car horns in approval.

As automakers shift from horsepower to kilowatts to comply with stricter environmental regulations amid an age of electric cars that appears ahead of schedule, investors are looking for evidence that Tesla can increase its lead in electrification technology over legacy automakers who generate most of their sales and profits from combustion-engine vehicles.

While average electric vehicle prices have decreased in recent years thanks to changes in battery composition and evidence that they are better for the planet and household budgets, they are still more expensive than conventional cars, with the battery estimated to make up a quarter to a third of an electric vehicle’s cost.

Some researchers estimate that price parity, or the point at which electric vehicles are equal in value to internal combustion cars, is reached when battery packs cost $100 per kilowatt hour (kWh), a potential inflection point for mass adoption.

Tesla’s battery packs cost $156 per kWh in 2019, according to electric vehicle consulting firm Cairn Energy Research Advisors, with some studies noting that EVs save money over time for consumers, which would put the cost of a 90-kWh pack at around $14,000.

Tesla is also building its own cell manufacturing facility at its new factory in Germany in addition to the new plant in Fremont.

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Electric Vehicles Lower Electricity Rates by boosting demand, enabling fixed-cost recovery, and encouraging off-peak charging that balances the grid, reduces peaker plant use, and funds utility upgrades, with V2G poised to expand system benefits.

Key Points

By boosting off-peak demand and utility revenue, EVs spread fixed costs, cut peaker use, and stabilize the grid.

✅ Off-peak charging flattens load, reducing peaker plant reliance

✅ Higher kWh sales spread fixed grid costs across more users

✅ V2G can supply power during peaks and emergencies

Electric vehicles (EVs) are gaining popularity, and it appears they might be offering an unexpected benefit to everyone – including those who don't own an EV.  A new study by the non-profit research group Synapse Energy Economics suggests that the growth of electric cars is actually contributing to lower electricity rates for all ratepayers.

How EVs Contribute to Lower Rates

The study explains several factors driving this surprising trend:

• Increased Electricity Demand: Electric vehicles require additional electricity, boosting rising electricity demand on the grid.
• Optimal Charging Times: Many EV owners take advantage of off-peak charging discounts. Charging cars overnight, when electricity demand is typically low, helps to balance state power grids and reduce the need for expensive "peaker" power plants, which are only used to meet occasional spikes in demand.
• Revenue for Utilities: Electric car charging can generate substantial revenue for utilities, potentially supporting investment in grid improvements, energy storage solutions and renewable energy projects that can bring long-term benefits to all customers.

A Significant Impact

The Synapse Energy Economics study analyzed data from 2011 to 2021 and concluded that EV drivers already contributed over $3 billion more to the grid than their associated costs. That, in turn, reduced monthly electricity bills for all customers.

Benefits May Grow

While the impact on electricity rates has been modest so far, experts anticipate the benefits to grow as EV adoption rates increase. Vehicle-to-grid (V2G) technology, which allows EVs to feed stored power back into the grid during emergencies or high-demand periods, has the potential to further optimize electricity usage patterns and create additional benefits for electric utilities and customers.

National Implications

The findings of this study offer hope to other regions seeking to increase electric vehicle adoption rates and support California's grid stability efforts, which is a key step towards reducing transportation-related greenhouse gas emissions. This news may alleviate concerns about potential electricity rate hikes driven by EV adoption and suggests that the benefits will be broadly shared.

More than Just Environmental Benefits

Electric vehicles bring a clear environmental advantage by reducing reliance on fossil fuels. However, this unexpected economic benefit could further strengthen the case for accelerating the adoption of electric vehicles. This news might encourage policymakers and the public to consider additional incentives or policies, including vehicle-to-building charging approaches, to promote the transition to this cleaner mode of transportation knowing it can yield benefits beyond environmental goals.

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U.S. Offshore Wind Power Strategy leverages UK offshore wind lessons, contract auctions, and supply chains to scale renewable energy, build wind farms, cut emissions, create jobs, and modernize the grid to meet 2030 climate goals.

Key Points

U.S. plan to scale offshore wind via UK-style contracts, turbines, and supply chains to meet 2030 clean energy goals

✅ Contract-for-difference price guarantees de-risk projects

✅ Scale turbines and ports to cut LCOE and boost capacity

✅ Build coastal grids, transmission, and workforce by 2030

As President Joe Biden’s administration puts its muscle behind wind power with plans to develop large-scale wind farms along the entire United States coastline, the administration can look at how the windiest nation in Europe is transforming its energy grid for an example of how to proceed.

In the search for renewable sources of energy, the United Kingdom has embraced wind power. In 2020, the country generated as much as 24 percent of its electricity from wind power across the grid — enough to supply 18.5 million homes, according to government statistics. 

With usually reliable winds, the U.K. currently has the highest number of offshore turbines installed in the world, with China at a close second.

Experts and industry leaders say it offers valuable lessons on creating a viable market for wind power at the ambitious scale the Biden administration hopes to meet in order to confront climate change and help transition the U.S. economy to renewable energy.

“The U.S. is going to benefit hugely from the early investment that European governments have put into offshore wind,” said Oliver Metcalfe, a wind power analyst at BloombergNEF in London, an independent research group.

Big American plans
On Oct. 13, the White House announced ambitious offshore wind plans to lease federal waters off of the East and West Coasts and Gulf of Mexico to develop commercial wind farms.

The move is part of Biden’s goal to have 30,000 megawatts of offshore wind power produced in the United States by 2030, with projects such as New York's record-setting approval highlighting the momentum. The White House says that would generate enough electricity to power more than 10 million homes and in the process create 77,000 jobs. 

But there is a chasm between where the U.S. is now and where it wants to be within the next decade when it comes to offshore wind power.

“We’re the first generation to understand the science and implications of climate change and we’re the last generation to be able to do something about it.”

The U.S. is not new to wind power; onshore wind in states such as Texas, Oklahoma and Iowa supplied 8.2 percent of the country’s total electricity generation in 2020, according to the U.S. Department of Energy. 

But despite its long coastlines, offshore wind has been a largely untapped resource in the U.S. With a population of about 332 million people, the U.S. currently has just two operational offshore wind farms — off Rhode Island and Virginia — with the capacity to produce 42 megawatts of electricity between them, far from the 1 gigawatt on-grid milestone many are watching. 

In contrast, the U.K., with a population of 67 million people, has 2,297 offshore wind turbines with the capacity to produce 10,415 megawatts of electricity.

Power station or a park?
Just outside of central Glasgow, the host city for the U.N. climate change conference known as COP26, the fruits of years of effort to move away from fossil fuels can be seen and heard

International financiers, including the World Bank are helping developing countries scale wind projects to meet climate goals.

Whitelee Windfarm, the U.K.’s largest onshore wind farm, spreads across 30 square miles on the Eaglesham Moor and includes more than 80 miles of trails for walking, cycling and horseback riding.

With its 539 megawatt capacity, it generates enough electricity for 350,000 homes — more than half the population of Glasgow. 

On a recent gusty fall day, Ian and Fiona Gardner, both 71, were walking their dogs among the wind farm’s 360-foot-tall turbines  

“This is a major contribution to Scotland, to become independent from oil by 2035,” Ian Gardner, an accountant, said. 

Thanks to the rapid technological advances in turbine technology, this wind farm that was completed in 2009, is now practically old school. The latest crop of onshore turbines typically generate double the current capacity of Whitelee’s turbines.

“It took us 20 years to build 2 gigawatts of power. And we’re going to double that in five  years,” said McQuade, an economist. “We can do that because machines are big, efficient, cheap and the supply chain is there.” 

The biggest operational offshore wind farm in the world right now, Hornsea Project One, is about 75 miles off England’s Yorkshire coast in the North Sea.

Owned and operated by Orsted, a former Danish oil and gas giant, in partnership with Global Infrastructure Partners, its 174 turbines have the capacity to generate 1.2 gigawatts — enough to power over 1 million homes and roughly equivalent to a nuclear power plant. 

Benj Sykes, Vice President of U.K. Offshore Wind at Orsted, called Hornsea One a “game changer” in a recent phone interview, citing it as an example of how the industry has scaled up its output to compete with traditional power plants.

But massive projects like Hornsea One took decades to get up and running, as well as government help. According to Malte Jansen, a research associate at the Centre of Environmental Policy at Imperial College London, the British government helped facilitate a “paradigm shift” in renewable energy in 2013.

The electricity market reform policy set up a framework to incentivize investment in offshore wind farms by creating an auction system that guarantees electricity prices to developers in 15-year contracts, alongside new contract awards that add 10 GW to the U.K. grid. 

This means there is no upside in terms of market price fluctuation, but there is no downside either. The policy essentially “de-risked the investment,” Jansen said.

The state contracts allowed the industry to innovate and learn how to develop even larger and more efficient turbines with blades that stretch as long as 267 feet, about three-quarters the size of a U.S. football field. 

While this approach helped companies and investors, it will also have an unintended beneficiary — the U.S., Metcalfe from BloombergNEF said. 

Developers are “taking the lessons they’ve learned building projects in Europe, the cost reductions that they’ve achieved building projects in Europe and are now bringing those to the U.S. market,” he said.

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

Key Points

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

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

✅ Complements photovoltaics by harvesting post-sunset infrared flux

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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