Tens of millions of passenger cars end up in scrap heaps annually worldwide, researchers estimate. While many are recycled for their metal, the rest appear to be lost causes – except to Francisco Cassis and his colleagues in Madrid, who regard these old hulks as something awfully intriguing: bicycles in waiting.

Products “upcycled” from the scrap heap typically conjure up images of sloppy welds and suspect dexterity – until, that is, you see how craftsmen can build precise, one-of-a-kind bicycles from old car parts. That’s the raison d’être behind the Bicycled initiative, an informal partnership between Lola Madrid, the advertising agency where Cassis works, and a local Madrid bikemaker. The results are downright sensible, if not visionary.

“To be honest, it is a little odd,” Cassis admits as he explains why an ad agency is attempting – in a sort of water-into-wine moment – to upcycle car carcasses into single-speed velocipedes. “But sometimes our talented people come up with amazing ideas that aren’t related to advertising, so we created a department to actually try and make stuff like this happen.”

With maker-centric online marketplaces such as Etsy.com flourishing, there is nothing new about upcycling. For years, clever people have converted wine bottles into candleholders and Mason jars into light fixtures, not to mention the ubiquitous toilets and tubs turned into flower planters. But as a global trend, upcycling – loosely defined as the process by which discarded materials are reimagined into something more valuable – is charting novel, more ambitious paths.

Take Akala sandals, fashioned from discarded vehicle tires in Kenya. In Mumbai, entrepreneur Anu Tandon Vieira, founder of The Retyrement Plan, transforms old tires and other recycled materials into weatherproof outdoor furniture. In Rwanda, Angaza Limited turns discarded vinyl banners into fashion-forward purses and handbags. And in the UK, French product designer Gaspard Tiné-Berès has created Short Circuit, which gives new life to old kitchen appliances.

What could be more symbolically resonant than taking a rusty old gas-guzzler and turning it into an emissions-free machine for the urban masses?

Unlike these efforts, however, a delicious irony lies at the center of Bicycled. What could be more symbolically resonant than taking a rusty old gas-guzzler and turning it into an emissions-free machine for the urban masses?

“A bike made from junked cars is a bike with an opinion,” says Cassis, Lola Madrid’s creative director. “And there’s the novelty of a bike that’s special.”

Part of the appeal lies in the fact that, like snowflakes, no two Bicycled bikes are alike. Singularity is the happy byproduct of melted-down sheet metal shaped into tubes for the bike’s welded frame; a belt-drive “chain” fashioned from a transmission belt; saddle covers from leather seating surfaces; reflectors from a turn-signal lamp; and a seat-post clamp from a door handle. It’s modern-day alchemy with an eco-conscious twist.

Compelling? Many people think so, as evidenced by the consumer response at the March 2013 SXSW (South by Southwest) music and media festival in Austin, Texas, where the concept was showcased.

“People loved it,” Cassis says. “We received 7,000 inquiries and advance orders, even though we said it would be an expensive bike [about 500 euros, or nearly $800]. The general reaction was, ‘Congratulations on an amazing idea. I want one.’”

Those enthusiasts likely will wait a while. Like many an Etsy artisan has discovered, it can be difficult to keep pace with demand. Melting down the sheet metal, then welding together a tubular frame and building the rest of one bike currently takes three months, Cassis says. And with at least 7,000 initial inquiries, that’s some daunting math.

“If you want to sell, say 500 or 1,000 bikes, and it takes three months apiece to make them, that’s crazy,” Cassis notes. “So we’ve currently taken a pause in building the bikes. In the long term, we’ll figure out how to make the frames faster, then resume production.”

Might demand diminish in the interim cooling period? Count Cassis among the sceptics , insisting that consumers are always drawn to products with a story to tell because that, in turn, is a story they can tell to others.

Closed for debate is this: With the European Environment Agency estimating that some 17m cars will be scrapped across the continent during 2015, there is little danger that Cassis and company would run out of source material.

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