How a rubbish idea could save the planet

In the first of his new columns, Roger Highfield gives readers the chance to take part in a 'truly rubbish experiment'.

Published: 7:00AM BST 29 Sep 2009
THE Massachusetts Institute of Technology is one of my favourite places on the planet. Its sprawling campus runs at a thousand ideas an hour, and it's there that I recently found out an absolute humdinger of an invention. It aims to show that when it comes to throwing stuff away, there's no such thing as "away" .
The project emerged from the SENSEable City Laboratory, run by Carlo Ratti, which harnesses sensors and hand-held electronics to help describe cities in a new way. As urban environments become ever more complicated and interconnected, they present us with new opportunities to study how they work – and to make them better places to live in.
On my visit to the lab, I stared at a computer screen as a map of Rome exploded with movement and flickering colour, showing the ebb and flow of Italian football fans as they surged into squares and bars after their team won the World Cup. The secret was to use mobile calls made by the fans to monitor their antics: when the game heated up, so did the call rate.
Now the professor wants to use the same simple mobile-phone technology to reveal the journeys taken by familiar everyday objects after we throw them out. The hope is that it will help to deal with one of the most pressing urban problems, both in practical and aesthetic terms: rubbish.
We are all used to the idea of separating different kinds of rubbish: a bin for this, a skip for that, a box for the other. But how do you know that all your diligent efforts paid off in the end?
This is where Ratti's Trash Track project comes in. His team have developed tags consisting of a battery-powered Sim card and motion sensor, encased in resin, which updates them about the location of a piece of rubbish every 15 minutes for up to eight weeks.
Lewis Girod, who designed the tags, says they can use the mobile phone network to pinpoint an object to within 100 metres or so in the city, and around half a mile in the country.
Ratti likens the use of these tags to injecting a radioactive substance into a patient in order to find blockages that might be causing health problems.
In this case, the blockages are problems with a city's waste-disposal system: by tracking the final resting place of pieces of waste, from coffee cups to fluorescent bulbs, they can discover whether stuff that can be recycled ends up in a landfill. That applies not just to glass and plastics, but valuable (or toxic) substances such as gold, aluminium, nickel, copper, zinc, lead, cadmium and mercury, too.
As soon as he had spelt out the potential, I asked Carlo if I could get hold of some tags for a pilot project. A few months later, I was able to sit in London and watch a similar screen, tracking 60 pieces of rubbish in Seattle. Each one had a story to tell.
On July 12, Musstanser Tinauli, an MIT project leader, threw a digital camera into a roadside rubbish bin in south Seattle. Two days later, it turned up in a residential area to the south, presumably adopted by a new owner. A clapped-out Dell laptop belonging to Ewen Callaway was donated to the Computer Recycling Service store in the suburb of Green Lakes, north of the city. Within a few days it, too, seemed to have found a new home.
Detective work by a colleague of mine, Catherine Brahic, revealed how 11 pieces, including a Spiderman shoe, a keyboard and a laptop battery, ended up near two recycling facilities. Three items ended up in shipping yards. A toy tossed into a recycling bin in western Seattle turned up five days later on a hill south of the city, near Maple Valley.
Overall, only two pieces of garbage found their way to Seattle's main landfill in Oregon: the city's waste-sorting appeared to be working.
"Trash Track has the potential to encourage people to make more sustainable decisions," says Assaf Biderman, director of the lab. He believes it will help us move closer to a garbage utopia where we recycle or reuse everything we can, with the help of far tinier, and far cheaper, versions of the tags.
Next month, the project will go large-scale, as 3,000 more pieces of garbage are tagged in New York and Seattle. But we are also offering 10 British residents the chance to tag their own property for an experiment over here. Nominations close tomorrow, so visit newscientist.com/projects/forms/trash to submit your ideas for what I reckon is the best rubbish experiment ever.
* Roger Highfield is the editor of 'New Scientist', and will be writing a regular column for 'The Daily Telegraph'