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How turbochargers are going to save the planet, while burning more rubber

When making power, there’s an old adage that says “there’s no replacement for displacement.”

However, carmakers are finding that they need to make engines smaller to meet stricter fuel-efficiency standards, while still providing the performance buyers are accustomed to.

Volvo proved those two things don’t have to be mutually exclusive this week, by unveiling a triple-turbocharged four-cylinder engine that makes 450 horsepower from just 2.0 liters of displacement.

It’s an impressive figure that shows the potential for small engines to produce big power, especially since the prototype is based on one of the Drive-E four-cylinders currently available in production Volvo cars.

Downsized engines appear capable of providing the power today’s car buyers expect, which is good news for  both car enthusiasts and hyper-milers. The next challenge, however, will be reproducing the characteristics of the larger engines these fuel-sippers will replace.

Turbo power

The Volvo Drive-E engine uses turbocharging to punch above its weight, and it’s not the only one. We’re in the midst of a turbo renaissance, with everything from midsize family sedans to luxury performance cars using the devices keep power levels high in a regulation-constrained world.

This is nothing new. When the first round of fuel-economy standards and gas-price spikes hit in the 1970s and 1980s, engineers found that turbochargers – that use exhaust gases to spin a fan and drive more air into an engine – were a handy addition.

What followed was an era of turbo-craziness, producing memorable machines like the first Porsche 911 Turbo, the Saab 99 Turbo, and the Buick GNX. On the track, turbos proliferated in Formula One, the World Rally Championship, and IMSA sports-car racing.

Related: 2015 Volvo V60 T5 Drive-E review

However, the power produced by these early turbos came at a price. Turbochargers have to spool up to produce boost, causing “turbo lag.” This meant that, sometimes, an aggressive jab of gas pedal was followed by … nothing.

This unruliness caused carmakers to explore other ways to improve efficiency, leaving turbocharging primarily to performance cars and a handful of more mainstream models until tightening global emissions standards made them relevant again.

Modern turbos are remarkably free of lag, allowing carmakers to shrink the engines they’re attached to. That’s why the new 2015 Ford F-150 will only be offered with one V8 engine, even though previous models were offered almost exclusively with eight cylinders, and why the Blue Oval thinks it’s time to offer a four-cylinder engine in the Mustang again.

2015 Volvo XC90 side by side

Electric slide

Smaller, turbocharged engines are conquering many realms of automobiledom, but there are still limits to how much power they can produce, and how smoothly they can deliver that power.

That’s why the Volvo Drive-E prototype has a secret weapon. Two of its three turbos are spun by exhaust gases, but the third is powered by electricity.

An electric motor doesn’t need to wait for gases to build up. Like the motors used to power so many other devices in the average car (or, sometimes, the car itself), this one can respond instantaneously.

That means plenty of power, with no waiting. With an electric turbo spooling up at low revs, an output figure that looks impressive on paper would also mean more in the real world, since that power would be more accessible. Imagine a four-cylinder engine that’s as powerful and responsive as a naturally-aspirated V8.

The prestige factor

Many customers want more than horsepower, after all. Buyers of luxury cars are used to the smooth power delivery of big, naturally-aspirated engines. A smaller engine might be able to move a leather-lined luxury sedan, but some drivers still may not approve if said engine feels like it was pulled from a hot hatchback.

That’s why electric turbochargers are mostly getting attention from upscale carmakers. Before Volvo unveiled its 450-hp Drive-E engine, Audi demonstrated an electric turbo on the RS5 TDI concept, a diesel version of one of the German automaker’s sportiest cars.

Audi will also be the first to put an electric turbocharger into production. While Volvo hasn’t discussed any production plans, Audi confirmed recently that it will use one on the SQ7, a performance version of the next-generation Q7 SUV.

Ferrari is also reportedly looking at an electric turbo to help increase responsiveness in an upcoming supercharged engine. If it’s good enough for that storied Italian brand, surely it’s good enough for everyone else.

2014 Audi RS5 TDI ConceptConclusion

Downsized engines have already improved the efficiency of many new cars, and the electric turbocharger could help them do the same with

Officially, the triple-turbo Volvo Drive-E engine is just for show, but it’s easy to imagine one powering a large SUV like the recently-unveiled 2015 XC90, a big sedan, or a very hot performance car.

This might take some getting used to, of course. Giving up the roar of an uncorked V8 won’t be easy, and drivers will still have to remember that driving like The Stig will still result in poor fuel economy, even with fewer cylinders.

Still, new technology will likely help car enthusiasts have their cake and eat it to, providing the power they want, and the fuel economy they need.

Stephen Edelstein
Stephen is a freelance automotive journalist covering all things cars. He likes anything with four wheels, from classic cars…
The week in EV tech: From sky-high dreams to ground-level drama
tesla robotaxi feud alef in transition flight

Welcome to Digital Trends’ weekly recap of the revolutionary technology powering, connecting, and now driving next-gen electric vehicles. 
Buckle up, folks — this week we’re taking off with a look at the futuristic dream of flying electric cars possibly gliding above U.S. roads sooner than you think. But before we get carried away, let’s bring it back down to the bumpy road of present-day realities.
Even if you’re mostly interested about the tech powering the electric vehicle (EV) revolution, it’s become increasingly hard to avoid the politics around it: You guessed it, we’re talking about this week’s public feud between Tesla CEO Elon Musk and U.S. President Donald Trump.
What does this have to do with EV tech? Well, quite a lot actually. For starters, the technology behind Tesla’s Autopilot and Full-Self Driving (FSD) modes may return in the crosshairs of regulators: Despite the names, these are still driver-assist features that require active driver supervision, and until Trump’s election, they had been under heavy scrutiny by safety regulators for several years.
Last year, the National Highway Traffic Safety Administration  (NHTSA) launched an investigation into 2.4 million Tesla vehicles equipped with FSD. Big questions remain about the driver-assist system's performance under adverse, yet naturally-occurring conditions such as fog, sun glare, rain, and snow.
When Musk, who spent about $275 million to help elect Trump, was appointed to head a newly-created Department of Government Efficiency (DOGE), it raised more than a few eyebrows about his power and influence over the regulators who are supposed to oversee traffic safety, and therefore Tesla.
It didn’t help that the Trump administration followed Musk’s recommendations and relaxed crash-reporting requirements put in place since 2021, while also relaxing rules to accelerate the deployment of fully-automated robotaxis.
The Trump/Musk clash takes place just as Tesla is due to launch its robotaxi pilot progam in Texas later this month. While Trump is now threatening to pull billions of dollars in government subsidies and contracts from Musk’s companies, it’s unclear whether he might pressure the Department of Transportation to again tighten the regulatory screws on Tesla. What is clear is that Trump has never been a fan of electric vehicles and is already trying to end federal subsidies on EV purchases and leases. And while he had made a big deal about buying a bright red Tesla Model S back in March, Trump now says he wants to sell it.
Back to the tech
Meanwhile, Tesla is still required to respond to information and data requests from NHTSA regarding the safety of its robotaxis by July 1. And ultimately, it should come down to the performance of the technology.
For Autopilot and FSD, Tesla has opted for less expensive navigational tech relying on multiple onboard cameras that feed AI machine-learning models. But especially for so-called adverse driving conditions, it’s the more expensive technology relying on a blend of pre-mapped roads, sensors, cameras, radar, and lidar (a laser-light radar) which has received the nod of regulators.
Waymo, the sole robotaxi service currently operating in the U.S., and Zoox, Amazon’s upcoming robotaxi service, both use that blend of navigational tech.
For its robotaxis, Tesla is said to have upped its game in terms of autonomous driving with its Hardware 4 (HW4) technology, which does include radar sensors and promises enhanced environmental perception.
Will that be enough for Tesla to convince regulators, catch up with Waymo, or compete effectively with Zoox?
We’ll have to wait and see.
Flying cars
In a recent edition, we noted that while consumer confidence about robotaxi technology is on the rise, most people also want more data before they hop into a self-driving vehicle.
What about flying taxis? According to a recent survey by Honeywell, nearly all U.S. airline fliers, or 98%, said they would consider using a so-called electric vertical take-off and landing vehicle, or eVTOL, as part of their travel journey.
But while the buzz around flying electric vehicles has mostly focused on air taxis— like Archer Aviation’s Midnight, expected to fly athletes around the 2028 LA Olympics, or Joby’s slick air taxi, backed by Toyota — one California startup is shooting for something a little more... driveable.
Meet Alef Aeronautics, a Bay Area company that wants to put the “car” back in “flying car.” This week, Alef announced it has received over 3,400 pre-orders for its electric flying vehicle, the Model A — and get this: it’s not a futuristic prototype gathering dust in a lab. Alef says production could begin by the end of 2025, or early next year.
On the ground, the Model A operates like a low-speed electric car, complete with hub motors in the wheels and—wait for it—a real steering wheel. You can legally drive it at up to 25 mph on public roads, parking it in a normal garage like any other EV. It’s refreshingly manual in an increasingly hands-free world.
But when it's time for lift off, the steering wheel takes a backseat. For vertical takeoff and flight, the Model A transforms into a drone-like aircraft. Its cabin rotates sideways to create lift, and eight electric rotors—controlled by a flight system and joysticks—take over. No pedals, no yoke, just a bit of joystick magic (or autopilot, if you prefer).
The Model A has already received the nod from regulators for test flights.
While the $300,000 price tag won’t fit everyone’s budget, the company is clearly betting on a future where you don’t have to choose between a car and a flying machine—you can have both.

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8 key things you need to know from Apple’s WWDC 2025 event
From a fresh look and updated names, to new features, more intelligence and live translation
iOS 26, iPadOS 26 and macOS 26 shown on devices.

The WWDC 2025 keynote ran for just over an hour and a half. For those of you who don't fancy sitting through the whole presentation, we've pulled out the key things you need to know from the latest Apple event.

1. Welcome to the 26 club

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Tesla’s robotaxi service is almost here, but it’s not the car you want to see
Silver Tesla Model Y Juniper side

Tesla chief Elon Musk has said that the automaker is aiming to launch its robotaxi service on June 22, in Austin, Texas.

“Tentatively, June 22,” Musk said in a post on X on Tuesday, adding: “We are being super paranoid about safety, so the date could shift.”

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