Usability of Carbon Footprint Calculators

So as part of World Usability Day’s focus on sustainable design, User Vision had a look at how online Carbon Footprint Calculators might help nudge people into a more sustainable lifestyle. We looked at The Daddy of calculators in the UK, the cross government department Act on CO2 campaign’s calculator.

Act on CO2 Calculator

Through usability testing we got some feedback about user’s attitude before using the calculator. People were pretty neutral about the statement “I do enough already” and slightly disagreed with the suggestion that they would do more if it was easier. But they were clear that their personal emissions did contribute to the problem, and didn’t agree that given their work, family size and lifestyle, that their levels of usage were inevitable.

Finally, most disagreed that there wasn’t an area where they would lower their CO2. Which in all, is a pretty sympathetic audience for being influenced to do more.

Working our way through the calculator did feel like work. Question followed question. A vague progress bar which went largely unnoticed and neither told you how many steps there were nor what the next steps might be. Section followed section with no idea of a end in sight. Users visibly wilted as they dutifully slid sliders and dropped down lists. Their only reward, at the end of each section, was a figure in tonnes of CO2 they consumed.

There was no context to this. No indication of whether it was good or bad. No hint at what was the worst offender in that section. No suggestion as to how they might improve the figure. It was just a bit baffling. They might as well be told they used 3.24 Wibble Wobbles per annum for all the sense it made.

Finally, at the end, users were able to compare their measure to the national average and to the average of people “like me” – which really meant people who lived in the same sort of house. That was good. You could also find out how many hundreds of thousands of cups of tea or party balloons you’re emissions represented. That was silly.

In the end, users were left with a strong sense that the calculator was frustrating to use, with a lot of unnecessary features. It did look attractive. But it missed an opportunity to influence and engage them throughout the process. By the time the calculator produced its results; tired users were not keen to see what practical steps they might take to reduce their emissions. They had emitted too much of their own information, and were reluctant to emit more.

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