The art of persuasion: Steering toward sustainable solutions

An estimated 55% of emissions reduction in the IEA’s Net Zero Emissions scenario requires the active involvement of citizens and consumers, e.g., choosing to install a solar water heater, or buying an electric vehicle. An additional 8% of emissions reductions are expected to stem from behavioral changes and materials efficiency gains that reduce energy demand.¹ To achieve Net Zero, people need to be brought on board—this is why persuasion is so important. We highlight 10 techniques based on psychological and social theories that have been used to encourage more sustainable behavior.²

1. Reduce barriers: Make sustainable behavior less time consuming, less effortful, or cheaper.
   Example: “Blue Jeans Go Green” was launched in 2006 to recycle old denim and turn it into insulating material for buildings, pet bed inserts, and food or pharmaceutical packaging. The company partners with different retailers who offered their customers a discount for donating old jeans to their store. Since its launch, the program has recycled 5,200,000 pieces of denim and diverted 2,630 tons of denim from landfills.³
2. Gamify: Add elements of game design to make reaching sustainability goals feel like winning in a competition.
   Example: In 2018, researchers in Australia and the U.S. tested a gamified app with three mini games titled “Temperature Defender,” “Power Raid,” and “Fully Loaded,” to encourage thoughtful and sustainable consumption of household energy.^4,5 At the end of the testing period, researchers found that this led to a decrease in household energy consumption and a significant difference in pre- and post-game energy bills. The 326 participants averaged quarterly savings of USD 55.44 in their energy bills.⁶
3. Educate: Provide information about the impact of people’s behaviors to encourage them to make more sustainable decisions.
   Example: Researchers in Germany found that carbon footprint tracking apps that educate users on their carbon emissions and provide feedback on the environmental impact of their choices regarding mobility, food, heating, and household activities helped to decrease users’ carbon emissions by an average of 23%.⁷
4. Change mental models: Change the way people view and understand the world to alter their responses.
   Example: The Climate Clock is an 80 feet long screen positioned four stories above New York’s Union Square, displaying the countdown until the worst effects of climate change become irreversible. The clock aims to frame climate change as a concrete event marching toward us, rather than an abstract scenario that we may one day reach. Other Climate Clocks have since been installed in Berlin, Rome, Seoul, and Glasgow.⁸
5. Personalize: Bring issues closer to home and encourage accountability through personal examples.
   Example: In a 2015 study in Spain, researchers found that, compared to traditional informational materials, portable air quality sensors that provided information about the participants’ most frequented streets led to greater awareness of urban air pollution and information-seeking behavior in users.⁹
6. Link cause and effect: Connect people’s behavior and its consequences to improve the psychological rewards of sustainable behavior.
   Example: “To Good To Go,” an app launched in 2015, is designed to tackle food waste, and displays the electricity use and carbon emissions that the user has avoided.¹⁰ The app connects restaurants who provide cut-price “mystery bags” of leftover food at the end of the day with potential customers on the app who can browse participating restaurants.¹¹ With each purchase, the app updates the user’s profile to display the CO₂e they avoided in easily understood terms, such as electricity, full smart phone charges, cups of hot coffee, and time showering.¹² The app now operates in 17 countries across Europe and the U.S. and has 90 million registered users plus 155,000 active partner businesses across the globe. Since its launch, over 300 million meals have been saved, which translates to taking about 135,000 cars off the road for a year.¹³
7. Provide experiences: Give people first-hand experiences to encourage behavioral change because it is less abstract than information gained through other sources.
   Example: Researchers in Switzerland found that a virtual reality (VR) experience demonstrating a model of the Aletsch glacier melting over the course of 220 years led to higher environmental awareness among participants. This increase in awareness was significant only for the VR group and not for the control group, who watched a video or read some text about the melting glacier.¹⁴
8. Establish social norms: Make sustainable behavior the norm to encourage people to modify their actions.
   Example: Google’s Project Sunroof, launched in 2015, aims to amplify and utilize the social pressure effect by showing its users which and how many of their neighbors have installed solar panels.¹⁵ By using information gathered by a machine learning algorithm that is trained to recognize solar panels from satellite images, it places a red dot over buildings with solar power on a satellite map of the user’s neighborhood. Project Sunroof also informs users how much sunlight hits their rooftop, how much they could save by installing solar panels, and provides information on local panel providers to do the installation.^16,17,18 Research has shown that families who viewed their neighbors’ solar panels more often, whether through longer commutes or by having more family members in their home, were more affected by peer influence.¹⁹
9. Apply social pressure: Apply social rules to convince people to act sustainably.
   Example: In 2008, when U.S. researchers altered the wording on hotel signage to state “most guests in the hotel reuse their towels,” there was a 26% increase in reuse. When they specifically referenced the guests who had previously stayed in the very same room, the rate of reuse went up by 33%.²⁰
10. Utilize peer pressure: Establish that people’s peers are acting sustainably, because people are more likely to behave similarly if they think their acceptance by their friends depends on it.
    Example: Researchers in the U.K. developed “Wattsup,” a version of an energy monitor that shared its user’s personal energy consumption on Facebook. Half of the participants were exposed to their friends’ energy use as well as their own, while the other half saw only their own energy use. At the trial’s midpoint, the two groups switched, so that both experienced exposure and non-exposure to peer information. The researchers found the seeing peers’ energy consumption levels was linked to a 17% fall in participants’ consumption.²¹

Achieving Net Zero by 2050 will require the full complement of tools to change behavior and the wider economy, from blunt instruments like regulations, tariffs, and taxes, to softer methods of persuasion like the ones outlined above. These techniques are not about manipulation or coercion, but rather about engaging people and providing information in a compelling way. As the above-mentioned examples show, deploying these techniques can judiciously effect meaningful changes in behavior and nudge people into more sustainable habits, while respecting their autonomy.

^1.International Energy Agency, 2023, Net Zero Emissions by 2050: A Roadmap for the Global Energy Sector.
^2.Fogg, B.J., Danielson, D., and Cuellar, G., 2007, Motivating, Influencing, and Persuading Users
^3.https://bluejeansgogreen.org/about-us
^4.Mulcahy, R., Russell-Bennett, R., and Iacobucci, D., 2020, Designing Gamified Apps for Sustainable Consumption: A Field Study.
^5.The three mini games focused on fan temperature settings, turning off lights and appliances, and washing full loads of laundry, respectively, awarding points for sustainable behavior. Each game also provided additional sustainability tips that users could enact in their home to nudge users beyond the behaviors encouraged in the mini games.
^6.Mulcahy, R., Russell-Bennett, R., and Iacobucci, D., 2020, Designing Gamified Apps for Sustainable Consumption: A Field Study.
^7.Hoffmann, S., Lasarov, W., Reimers, H., and Trabandt, M., 2023, Carbon Footprint Tracking Apps. Does Feedback Help Reduce Carbon Emissions? Journal of Cleaner Production.
^8.https://climateclock.world/story
^9.Oltra, C. et al., 2017, Public Engagement on Urban Air Pollution: An Exploratory Study of Two Interventions. Environ Monit Assess
^10.Wells, C., 2023, Want to Fight Climate Change and Food Waste? One App Can Do Both. NPR.
^11.“Too Good To Go” is an app launched in 2015 in Copenhagen to combat food waste by restaurants. According to the app’s 2023 Impact Report, worldwide, up to 40% of food produced is wasted, accounting for 10% of all human-caused greenhouse gas emissions.
^12.Wells, C., 2023, Want to Fight Climate Change and Food Waste? One App Can Do Both. NPR.
^13.Too Good To Go., 2023. Impact Report.
^14.Thoma, S. P., et al., 2023, Increasing Awareness of Climate Change with Immersive Virtual Reality. Frontiers in Virtual Reality
^15.Potenza, A., 2017, Google’s Project Sunroof Will Peer Pressure You to Get Solar Panels. The Verge.
^16.Potenza, A., 2017, Google’s Project Sunroof Will Peer Pressure You to Get Solar Panels. The Verge.
^17.In 2012, researchers assembled a dataset of residential solar panel installations between 2001 and 2011 in three investor-owned utility regions in California. To test for the effect of peer influence, researchers accounted for other factors such as a feedback loop or homophily and concluded that each new installation of solar panels in California raised the daily probability of another installation in the same zip code by 0.78 percentage points.
^18.In 2014, a study found similar peer effects when looking at Connecticut. Graziano, M., and Gillingham, K., 2014, Spatial Patterns of Solar Photovoltaic System Adoption: The Influence of Neighbors and the Built Environment. Journal of Economic Geography.
^19.Bollinger, B., and Gillingham, K., 2012, Peer Effects in the Diffusion of Solar Photovoltaic Panels. Marketing Science.
^20.Goldstein, N. J., Cialdini, R. B., and Griskeviciu, V., 2008, A Room with a Viewpoint: Using Social Norms to Motivate Environmental Conservation in Hotels. Journal of Consumer Research.
^21.Foster, D., Blythe, M., and Lawson, S., 2010, Competitive Carbon Counting: Can Social Networking Sites Make Saving Energy More Enjoyable? Conference: Proceedings of the 28th International Conference on Human Factors in Computing Systems.

The author thanks the following people for their valuable input: Richard Mylles, Jackie Bauer.