At Least London’s Snooping Bins Save Carbon Emissions

Recycling bin maker Renew has been told to stop a trial in which its bins tracked passing mobile phones, because the City of London is concerned about privacy. But besides the issue of snooping, are the bins even green?

The bins are fitted with a digital screen and an Internet connection which both use electrical power. This causes significant greenhouse gas emissions, which must reduce the environmental benefit of the bins – whose main purpose, after all, is to reduce waste. Happily for Renew, however, the figures appear to show the bins do actually save more emissions than they produce.

Burning as much as it saves?

Renew has 200 recycling bins or “Renew Pods” in the City of London, which collect 12 tonnes of newspapers every month, according to the firm’s site.  Over the course of a year, each bin collects “1.5 tonnes of recyclables, primarily paper”.

That sounds like a lot of paper. Where does it all come from?  “The City has had a major green issue for years due to the high volume of free news-sheet that get distributed in central London,” Renew’s CEO  Kaveh Memari told TechWeekEurope. A newspaper weighs around 200g, so each bin is collecting the equivalent of 7500 newspapers a year. That’s an average of 20 a day (or actually nearer 30, since the free sheets don’t come out at the weekend)

Figures from DEFRA say that recycling a kilo of paper saves 1.5kg of greenhouse gas. This  means that over a year, each bin saves 2.25 tonnes of CO2.

That’s good, but each bin’s electronics use power. Renew is using as little as possible, says Memari: “We set a challenge for our product teams.  Each screen had to use less than 100 Watts of power, and less where possible.” If the bins use 100W 24 hours a day, that would be 2.4kWh of energy per day.  In the UK, with its heavy use of coal and gas fired power plants, each kWh generates 600g of CO2, so a bin could be causing 1.44kg of CO2 per day.

In fact, the figure should be less.  “Each screen independently controls its backlights based on orientation, time of day, season, building shadows etc,” says Memari. Because London goes from 16 hours of daylight in summer to less than eight in the winter, the screens save about 35 percent of the energy they might use over a year, he claims.

That would work out at 341kg of CO2 over the year.

I reckon the figure would be higher, especially  for the smart bins that are scanning for Wi-Fi signals. I don’t think the power needs of the Renew Orb scanner have been included. But even so, there’s a big margin there.

Of course, you could argue that if Renew didn’t recycle the paper, someone else would, without the energy-wasting display screens. But Memari says the cost and difficulty would prevent this, because the paper has to be collected in receptacles where terrorists can’t easily plant a bomb. “The cost of running such a scheme would be incredibly high on the tax payer,” he says, “and so we found a solution using media to finance both the requirements to the public purse.”

So although the screens do detract from the environmental benefits, overall they are a positive thing, because they enable the recycling bins to happen at all.

All the same, I still feel there is some conflict of aims here. The “green” thing to do, as well as recycling, would be to reduce consumption. And the underlying aim of all the commercial ads on these bins is the opposite.  They are all about making people buy and consume more.

What happens if the ads are so successful that they generate a boom at Starbucks and the bins disappear under a mound of cardboard cups?

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