Investigating the usability of the Government's carbon calculator

Is it possible to change people's behaviour if they don't know what they're doing in the first place? We are frequently encouraged to reduce our "Carbon Footprint" but that is hard to achieve when there is a lack of understanding about what our carbon footprint actually is. This is especially difficult if "not knowing what it is" can mean both how large it is and what causes it in the first place.

As part of World Usability Days's focus on sustainable design, User Vision investigated whether Carbon Footprint Calculators can be used to nudge people into a more environmentally friendly lifestyle. We evaluated the UK Government's Act on CO2 campaign carbon calculator: http://carboncalculator.direct.gov.uk.

Before challenging users to try to use the calculator, we asked a few general questions about their carbon footprint. Many were neutral about the statement "I do enough already" and slightly disagreed with the suggestion that they would do more if it was easier. However, they were clear that their personal emissions contribute to the problem, and didn't agree that their levels of usage were inevitable given their job, family size and lifestyle. Finally, most agreed that there are areas where they could lower their CO2.

Working our way through the calculator was a slow process. There seemed to be endless questions and the vague progress bar, which went largely unnoticed, told you neither how many steps there were, nor what the next steps might be. Users visibly wilted as they dutifully slid sliders and dropped down lists. At the end of each section, the only reward was a figure of how many tonnes of CO2 they had emitted. This figure was meaningless as there was no indication of whether it was good or bad, above or below average. There were also no suggestions of how to improve the figure or which areas could be most easily reduced.

After completing all of the sections, users were able to compare their total carbon footprint to the national average and to the average of "people like me" - which meant people who live in a similar house. If you so desired, you could also find out how many hundreds of thousands of cups of tea or party balloons your emissions represented.

Overall, users were left feeling frustrated by the calculator and its unnecessary features. Although it looked attractive, it missed the opportunity to influence and engage them during the process. By the time the calculator finally produced its results, tired users were not keen to spend more time finding out about the practical steps they could take to reduce their emissions.

Chris Rourke is Managing Director and founder of usability consultants User Vision.

For more information, please visit the User Vision website