Assaf Biderman thinks he has just the thing for you.

Biderman is the CEO of a Cambridge, Mass.-based startup called Superpedestrian, which includes among its backers Tony Fadell, sometime ‘godfather of the iPod and founder of the Google’s Nest thermostat. This week sees the hard launch in Europe of his Copenhagen Wheel, a device that promises to transform your cycling experience and—in due course—help solve the problem of moving billions of people to and from work every day without putting impossible stress on the environment.

The wheel consists of a rechargeable electric motor in a red hub, and can be retrofitted onto the rear wheel of any conventional bike, effectively turning it, on demand, into an e-bike that can take you up to 30 miles at speeds of 12-13 mph on one battery charge.

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“We developed new sensors, controllers, and alloys to enable an e-bike that performs exactly like a traditional bike, but makes you 10-20 times stronger,” says Biderman. That combination of technology, controlled from a smartphone app, allows force to be generated completely synchronized with the pedal stroke, he says. Pedal, and the energy is amplified automatically; brake, and the kinetic energy is stored in the battery. The result, Biderman claims, is something that is “sexy, affordable and fun to use.”

The middle part of that might have to be taken with a grain of salt for the near future, given that e-bike prices start around the $2,000 level in Europe (the Copenhagen Wheel is priced at $1,600 plus shipping plus sales tax). But e-bikes are, undeniably, increasingly big business.

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According to industry data, sales in Europe have gone from 98,000 in 2006 to 1.67 million last year, a 15-fold increase. Last year alone, they grew 22%. In Belgium, they now account for as much as 50% of all new bikes sold. All that explains why Superpedestrian is focusing its marketing efforts for the product in Europe. (The product owes its name to its origins as the joint brainchild of MIT’s Senseable City Lab and the Mayor of Denmark’s capital city, who wanted to get more commuters out of their cars and on to bikes).

But the trend goes well beyond the Old Continent. Navigant Research estimates that the global market for e-bikes will be worth over $24 billion a year by 2025, from $15.7 billion last year. That’s a glittering prize for a company that has so far only needed $28.5 million in startup capital to date (it will be looking for more in due course, Biderman says).

As Biderman sees it, one of the strongest arguments for innovations such as his is that cars, as they are designed today, can’t solve the problems of urbanization, even if ride-sharing as a model takes off as many expect it to (the same logic is behind the rash of investments in flying taxi projects this year by the likes of Uber, Germany’s Daimler and China’s Tencent).

The proportion of humans living in cities is set to rise from 54% today to 66% by 2050, according to the UN, and even if one allows for a big increase in urban mass transit networks, it’s hard to see how today’s city grids will be able to cope even in the U.S., let alone in places like London or Rome. Ultimately, Biderman reckons, the e-bike has more to offer in terms of users’ control over their personal space, and their ability to defeat congestion.

“You have to optimize the vehicle,” he says. “You’re not going to fill a five-seater all the time.”