British band Coldplay is trying to turn its fans into climate rock stars with an app that rewards them for bringing low-carbon transport to concerts during the group’s current world tour.

There were 80,000 downloads of the smartphone app during the first leg of the 2022 tour, according to Coldplay, and the band says estimated emissions from fan tours fell nearly 50 percent compared to their 2016 shows. -2017. However, a review of those numbers indicates the limits of using motivational apps to calculate and offset carbon emissions.

Coldplay says their goal is to make their “Music of the Spheres” tour as sustainable as possible. To that end, the band is doing everything from installing solar panels in concert halls to traveling on biofuel-powered jets and electric vehicles.

Much of the carbon footprint of a world tour; however, is generated by the tens of thousands of fans who travel to see the band. The SAP SE-powered app shows fans their estimated carbon emissions for a round trip to a show if they travel by car, train, plane, bicycle, or other forms of transportation. Concertgoers are encouraged to choose a climate-friendly mode of travel and those who do will receive a code for 10 percent off Coldplay merchandise.

Transportation data collected by the app is used to calculate the carbon footprint of the audience. “We are committed to reducing all of these emissions through nature-based solutions such as rebuilding and conservation,” the band says on their concert website, stating that they will also plant and maintain at least one tree for every ticket sold.

“In general, these kinds of small incentives tend to have a small effect,” said Seth Wynes, a postdoctoral fellow at Concordia University in Montreal who researches consumer behavior and climate change. “Transportation tends to be habit-driven. I would expect some people to change their minds about how they travel to a show, but not a lot of them.”

He also pointed out that nothing would prevent fans from committing to travel by train, for example, so they could collect a discount on Coldplay merchandise and then, on the day of the concert, drive an SUV to the venue, which would skew the carbon calculations of the band.

SAP Senior Vice President Ferose VR said “that’s always a possibility” but noted that “our goal was to create awareness by providing very gentle nudges.”

“If you can change a person’s mindset, that’s a good starting point,” he added. “Sometimes we don’t realize that when a band like Coldplay does it and multiplies hundreds of thousands of fans, it can have a significant effect.”

The app’s fan carbon footprint calculation is based on UK “conversion factors” that convert emissions from various types of transport into estimates of pounds of CO₂ emitted per person. But such conversion factors differ for shipping in other parts of the world where Coldplay is on tours, such as the United States and Latin America.

“We did an approach, but I think it’s a reasonably good approach,” VR said. “We have to project the data for the entire number of fans that come to a stadium. So we don’t get very accurate data for everyone.”

The 2022 releases are based on data collected by the app, which did not exist for the 2016-2017 tour. The broadcasts for those shows are estimates based on “post-event surveys, ticket information, venues and promoters in each area the previous tour visited,” according to a statement provided by the band’s management to Bloomberg Green. “The total distance traveled by fans in each common vehicle type was then assessed and internationally recognized carbon emission conversion factors were used… to estimate the resulting carbon footprint.”

At concerts, Coldplay has been playing their hit song “The Scientist,” with Chris Martin singing, “I was just guessing numbers and figures. ” The band’s estimate that fan emissions on the first leg of the current tour nearly halved between 2016 and 2017 is not an assumption. But it is misleading, as different data and methodologies were used to calculate the carbon footprint of each journey.

Still, Wynes applauded Coldplay’s efforts to reduce the climate impact of their shows and increase concertgoers’ awareness of their transportation options. “It could help send a broader signal that members of a band that potentially a lot of people idolize do care about this, and tell their fans that maybe it’s something they should care about, too,” he said.