Nudging Governments into Buying Sustainably
What unsustainable behaviour needs to change:
In government and corporate procurement, conventional or “brown” products are often the default choice and lack eco-certifications. This is partly due to “salience bias“—where buyers tend to choose products that are more prominently displayed—and the “default effect,” where buyers stick with the first option provided. Because government purchases occur on a massive scale, sticking with non-sustainable defaults has a significant environmental impact.
By shifting these defaults to eco-labelled products in procurement processes (tenders), governments could encourage widespread sustainable choices and reduce emissions.
The Green Nudge:
The “Green Aisle” approach uses two behavioural nudges to promote sustainable choices in public and corporate procurement:
- Increasing Salience of Green Choices: By positioning eco-labelled items like FSC-certified paper or Energy Star electronics prominently in tender lists, the Green Aisle makes these sustainable products more visible. This concept builds on research by Thaler and Sunstein (2008), which found that placing healthy or sustainable options at eye level can encourage people to select them.
- Defaulting to Eco-Labels: Setting sustainable products as the default choice leverages the default effect, nudging buyers to stick with eco-friendly options. Pichert and Katsikopoulos (2008) demonstrated that when renewable energy was set as the default, 94% of participants chose it. Applying this principle to government procurement could significantly shift institutional purchasing toward greener choices.
The Result: Research indicates that when eco-labelled products are made more salient and the default option in tenders, buyers are far more likely to choose them. Making “green” the easy choice in government and corporate procurement has the potential to drive substantial reductions in emissions.
Small changes in procurement defaults can lead to big sustainability gains.
Do you know of any other nudges that promote sustainable procurement? Feel free to get in touch: hello@green-nudges.com
From Désirée Klingler, professor for public and climate law at the University of St. Gallen. She specialises in applying behavioural economics and law to guide governments and corporations towards socially and environmentally sustainable choices.
Bathroom basketball: Making recycling a fun habit
What unsustainable behaviour needs to change:
Recycling, despite its societal importance and widespread recognition as a positive norm, is inconsistently practiced, especially in the United States. This inconsistency stems from several challenges: unclear rules about what can be recycled, non-standardised sorting requirements, and the variable availability of recycling facilities.
Moreover, recycling often feels like an unrewarding task, leading many to prioritise convenience over responsibility. These hurdles, coupled with an absence of immediate gratification or visible impact, hinder the formation of lasting recycling habits. For recycling to become second nature, we need innovative solutions that are both clear and motivating.
The Green Nudge:
Enter Bathroom Basketball—a playful recycling intervention spotted at organic body care company Badger Balm in New Hampshire, USA. This innovative nudge combines gamification with behavioural insights to encourage sustainable actions. A small basketball hoop is mounted above a recycling bin, accompanied by a clear sign indicating which materials (e.g., toilet paper rolls) are recyclable. This setup transforms an otherwise mundane task into a rewarding game.
Why does this work so well? Four key principles are at play:
- Enticement: The setup is hard to resist. Holding an item in hand, the basketball hoop invites you to test your aim, creating a moment of engagement.
- Ease: Positioned near the source of recyclable materials, the hoop removes barriers to action, making recycling effortless.
- Clarity: The prominent hoop and sign ensure no ambiguity. The purpose is unmistakable—toss recyclable items here.
- Satisfaction: Whether you make the shot or not, the act of trying feels rewarding. This positive emotional response reinforces the behaviour, increasing the likelihood of repetition.
This gamified approach highlights how joy and achievement can make eco-friendly habits stick.
Do you know of any other nudges that gamify sustainability? Feel free to get in touch: hello@green-nudges.com
From Sara Conklin, Experience and Behaviour Designer at Acceladopt Green. Sara’s work focuses on accelerating climate solutions through experience design, empathy research, and behavioural science–breaking down barriers to sustainable action.
Wednesday Challenge: Inspiring Greener School Travel Choices
What unsustainable behaviour needs to change:
In New Zealand, as in many countries, car-dominated school drop-offs contribute to local CO2 emissions, traffic congestion, and safety issues around school gates. This over-reliance on single-household vehicles, driven by convenience and habit, reduces opportunities for children to engage in physical activity and build independence.
Transforming this behaviour is vital for fostering more sustainable and community-focused travel habits.
The Green Nudge:
Originating in Tauranga, New Zealand, the “Wednesday Challenge” encourages schools to embrace sustainable travel by gamifying the experience. Students log their travel choices every Wednesday—such as walking, biking, scooting, carpooling, or taking public transport—to earn points. Classes and schools compete for rewards ranging from pizza parties to cash prizes. The initiative has expanded to other cities like Auckland, Tairāwhiti and Christchurch, fostering a nationwide shift in mindset.
Excitement peaks during celebratory school gate activations. These events, featuring music, costumes, and spot prizes, turn school mornings into festive, community-building moments. Innovations like “Park & Stride” make the challenge accessible for families living farther away. Schools also receive visualised data on their progress, motivating participants to achieve even greater results.
The result: In Auckland schools, single-household car use dropped from 52% to 37% by the final Wednesday, highlighting the power of making sustainable behaviour fun. This Kiwi initiative shows how dedicating just one day a week to greener travel can drive meaningful change: reducing emissions, easing congestion, improving road safety, and instilling lifelong eco-friendly habits in students and families.
Do you know of any other nudges that encourage greener school travel? Feel free to get in touch: hello@green-nudges.com
From Anna Mosley, School Programme Coordinator for the Wednesday Challenge in New Zealand. Anna leads sustainability-focused travel behaviour change within schools, inspiring students and families to adopt greener habits. By designing strategic marketing, activations, and communication campaigns, she boosts engagement and helps schools embrace long-term environmental impact.
Turn your Fridge “Smart” to Reduce Household Food Waste
What unsustainable behaviour needs to change:
Despite growing awareness of food waste, Canadians are discarding food at alarming rates. The National Zero Waste Council reports that the average household throws away 88 kilograms of food annually, costing families over $1,300 and contributing significantly to environmental harm.
This waste accounts for 500 litres of water weekly, the equivalent of 142 unnecessary showers. In terms of carbon emissions, eliminating the food waste of even ten households would be the same as removing one car from the road. Clearly, more action is needed to curb this pervasive issue.
The Green Nudge:
Most of us don’t buy food intending to waste it, yet forgotten ingredients often spoil in the fridge. Waguta, a Vancouver-based startup, offers a simple yet transformative solution: a smart fridge system combining an app-based inventory with a fridge camera. The camera tracks what’s added or removed, automatically updating the app. The app alerts users when food nears its expiry date and suggests recipes to use it up, making meal planning easier and reducing waste.
The result: During a pilot study, Waguta provided ten families with groceries, use-by-date alerts, and recipe suggestions via an app. Participants reported enjoying more varied meals, less stress in meal planning, and a noticeable reduction in food waste. Waguta is now beta-testing its app and plans to roll out its full product, including the fridge camera, in January 2025.
Would you like to join Waguta’s early testing group or receive updates about the launch? Visit waguta.com to sign up.
Are you aware of any other nudges that prevent food waste? Feel free to comment or get in touch: hello@green-nudges.com
From Charlotte Gilmour, Managing Director of Environmental Impact at Yulu Impact Communications. With 18 years of expertise in communications, Charlotte is passionate about amplifying climate solutions and fostering collective action across sectors to combat the climate emergency. She introduces an inspiring initiative from Vancouver-based startup Waguta, designed to tackle food waste with innovative technology.
Japan’s Green Carb0n Club Rewards Eco-Friendly Living
What unsustainable behaviour needs to change:
In Japan, daily habits like the use of single-use plastics, including disposable water bottles, significantly contribute to environmental issues. Despite growing awareness, the convenience of these items often outweighs sustainable choices. This behaviour is influenced by ingrained habits and the immediate ease of disposable products.
Encouraging a shift towards reusable alternatives and eco-friendly consumption is essential to reduce waste and promote environmental responsibility.
The Green Nudge:
The Green Carb0n Club, is an initiative by the cities of Fujitsu and Kawasaki, designed as a smartphone app to promote eco-friendly lifestyles in Japan. Users earn points by engaging in activities such as attending environmental events, participating in app-based surveys, and sharing eco-friendly actions on social media. Accumulated points can be exchanged for coupons offering discounts on eco-friendly products and services. The app also features a city-building game, „Green Carb0n Farm,“ developed in collaboration with SEGA XD, which aims to enhance user engagement through gamification.
The result: Field trials from December 2023 to March 2024 revealed that the app successfully encouraged 1,190 eco-actions, resulting in an estimated CO2 reduction of 106.4 tonnes. Gamified features, such as personalized virtual spaces and unique experiences offered through partnerships, played a significant role in sustaining user participation and fostering a sense of community.
By integrating gamification with tangible rewards, the app not only incentivizes sustainable behaviour but also leverages Japan’s familiarity with point-based systems. While this approach effectively motivates individuals, it’s essential to balance these efforts with broader systemic solutions to ensure long-term impact.
Do you know of any other nudges that gamify sustainability? Feel free to get in touch: hello@green-nudges.com
From Riani Kenyon. With a degree in Anthropology, Riani began her career as a behaviour analyst in the consulting world, collaborating with companies such as Google, Volvo, Re/Max, and Change.org to develop strategies that effectively engage and influence diverse human behaviors.
How Framing New Year’s Resolutions Encourages Sustainability
What unsustainable behaviour needs to change:
Each year, millions of people commit to resolutions for a fresh start, yet most fail to sustain these goals beyond a few weeks. Resolutions framed negatively, such as “stop taking the car so much,” can feel restrictive and demotivating. This Avoidance-oriented approach tends to fall short compared to positive resolutions, which focus on adopting new behaviours.
Framing sustainable resolutions in actionable, positive terms—like committing to use public transport or cycle twice a week—can help individuals shift behaviours towards greener choices. By rethinking how resolutions are set, people are more likely to form habits that reduce emissions and contribute to broader environmental goals.
The Green Nudge:
Oscarsson et al. (2020) studied 1,066 participants and divided them into groups with varying levels of goal-setting support: an “active control” group, a “some support” group, and an “extended support” group. Support groups were coached to formulate approach-oriented goals, focusing on adopting positive behaviours instead of avoiding negative ones.
For example:
- Avoidance goal: “Drive less to reduce emissions.”
- Approach goal: “Walk or bike for two short trips per week.”
The result: The study demonstrated that participants with Approach-oriented resolutions had higher success rates throughout the year, with a majority successfully maintaining their resolutions well beyond a few weeks. Framing resolutions positively aligns with behavioural science principles, increasing motivation and adherence to sustainable behaviours. Clear, Action-focused goals not only nudge people towards adopting greener habits but also create a sense of achievement, making these habits easier to sustain over time.
Do you know of other nudges that help shift unsustainable habits? Feel free to comment or get in touch: hello@green-nudges.com
Sustainable Fashion Messaging: Positive or Negative—Which Works Best?
What unsustainable behaviour needs to change:
The fast fashion trend has created a cycle of overproduction and overconsumption. Manufacturers benefit from lowered costs via mass production, while consumers enjoy cheap, ever-changing wardrobes. However, this convenience comes at a significant environmental cost: increased greenhouse gas emissions and solid waste generation.
Ronda (2024) highlights two key psychological barriers to sustainable fashion adoption:
- Lack of awareness: Many consumers are unaware of the environmental harm caused by fast fashion and therefore don’t feel a need to change.
- Scepticism: Doubts about the efficacy and ethics of sustainability claims often dampen consumers’ motivation to purchase sustainable clothing.
The Green Nudge:
Research led by Professor Silvia Grappi from the University of Modena and Reggio Emilia explored how message framing affects younger adults’ willingness to use a second-hand clothing app. The study simulated Instagram stories with the following approaches:
- Positive-framed message: Featured a green, bright background emphasizing benefits like “help protect the environment” in the call-to-action.
- Negative-framed message: Featured a dark background highlighting consequences like “help stop the collapse of the environment.”
- Neutral message: Served as a control with no emotional framing.
The result: The study revealed that positive messaging was significantly more effective in promoting sustainable practices, regardless of consumers‘ scepticism about the efficacy and ethics of sustainability claims. Researchers suggest that the key driver is the heightened emotional response evoked by positive framing, which resonates with the desire for enjoyable experiences often associated with fashion purchases.
Do you know of any other nudges that encourage sustainable fashion? Feel free to comment or get in touch: hello@green-nudges.com
From Wyman Ko, a Lancaster University graduate with a MSc in the Psychology of Advertising. His interest lies in strategic communication design, including message framing, product naming, and behavioural interventions for consumer and shopper research.
Harnessing Pride to Drive Sustainable Behaviour
What unsustainable behaviour needs to change:
Policymakers, advocacy organisations, and many other groups often attempt to encourage sustainable behaviour by invoking negative emotions such as guilt. Their goal is to promote pro-environmental actions by highlighting the consequences of unsustainable choices and the responsibility for inaction regarding climate change.
However, these appeals often have limited impact.
The Green Nudge:
In an experiment, Schneider et al. explored the role of anticipated positive and negative emotional states – pride and guilt – in relation to pro-environmental behaviour.
They induced these emotions in three different ways:
- By displaying a sentence at the top of the screen while participants answered a survey;
- By asking participants to write a brief essay reflecting on the feelings associated with a real future decision;
- By imagining the emotions (pride vs. guilt) they would experience if they chose a green vs. non-green option, such as buying a car, dishwasher, cleaning product, or backpack.
After eliciting feelings of pride or guilt, participants were asked to choose between sustainable and non-environmentally friendly options.
The result: The researchers found that all forms of induced pride significantly increased pro-environmental behaviour compared to guilt. Participants were more likely to choose green options, select more eco-friendly features for their homes, express intentions to buy a green product in the next month, and engage in various green actions – all driven by positive emotions rather than negative ones.
Interestingly, both pride and guilt were equally influential only when it came to financial donations to an environmental advocacy organisation.
Are you aware of any other nudges that help to drive the adoption of sustainable products? Feel free to get in touch: hello@green-nudges.com
From Bianca Richter, a German studies scholar and psychology student specialising in environmental psychology. As part of her internship at Green Nudges Consulting, she explores opportunities where behavioural change can benefit the environment.
Responsible Travel Program: Practical Sustainability for Polish Tourism
What unsustainable behaviour needs to change:
“Save the planet” has become a well-intentioned yet vague “call-to-action” in sustainable tourism—often leaving Polish entrepreneurs in the tourism industry without clear, behaviorally targeted guidance for measurable change. Small accommodation owners eager to adopt eco-friendly practices face key behavioural barriers:
- Limited Resources: Many existing sustainability tools are overly technical, creating cognitive overload and leaving small businesses confused rather than empowered.
- Economic Constraints: Available tools or certifications are costly, reducing motivation for small operators who are unsure of their return on investment.
- Exclusivity: Many resources require insider membership, reinforcing the “outgroup bias” (the tendency to dislike members of groups that we don’t identify with) and creating barriers for independent operators.
- Greenwashing Concerns: Entrepreneurs committed to sustainable actions are wary of superficial certifications, which in turn undermine social trust.
- Neglect of Small Businesses: Most certifications in Poland target large hotels, leaving smaller accommodations without a clear pathway toward sustainability.
The Green Nudge:
To tackle these barriers, Slowhop.com launched the Responsible Travel Program—a free, step-by-step self-certification program specifically for small accommodations in Poland. The program simplifies complex environmental actions into accessible language and clear guidance.
The Responsible Travel Program addresses each key barrier:
- Cost-Free Access: It’s free, from assessment to certification, removing financial hurdles
- Inclusivity: Open to all types of small accommodations, creating a welcoming and equitable pathway to sustainability.
- Plain Language: Jargon-free resources and clear explanations make it easy to understand for non-experts.
- Anti-Greenwashing: With 250 specific questions probing actual actions (e.g., water conservation), it requires verifiable proof and avoids superficial claims.
- Focus on Small Accommodations: Tailored to small businesses, filling a gap left by larger, mainstream certification efforts.
The program supports lasting behavioural change by encouraging providers to set their own sustainability goals and track progress yearly.
The result: Since its launch, over 60 Polish accommodations have completed the Responsible Travel Program, with many preparing for recertification. As more businesses join, the program aims to transform Polish tourism with measurable data and impactful eco-actions.
Are you aware of any other nudges that help to promote sustainable tourism? Feel free to get in touch: hello@green-nudges.com
From Katarzyna Barwicka, Ecotourism Expert at Slowhop.com and the platform’s go-to authority on responsible travel. Since 2017, Katarzyna has immersed herself in ecotourism, exploring sustainable practices worldwide, from study trips in Armenia to environmental projects in Zanzibar.
Digital Nudges for Greener Transport Choices in the US
What unsustainable behaviour needs to change:
Transport behaviours are notoriously difficult to shift, largely because they are ingrained habits. During the COVID-19 pandemic, reduced commuting and increased remote work led to significantly decreased traffic levels in the US. However, by early 2022, traffic volumes were back above pre-2019 levels. This rebound highlights a key sustainability issue: private car use remains the default commuting option for many Americans, contributing to transport being responsible for 28% of US greenhouse gas emissions.
Addressing this challenge, a collaboration between The Behaviouralist, travel app Metropia, and the San Francisco Bay Area’s Metropolitan Transportation Commission (MTC) aimed to understand and influence commuter choices. A survey identified perceived barriers: cars were seen as convenient and without obstacles, while alternatives like carpooling and public transport were viewed as unreliable or unsafe. This insight led the team to test whether digital nudges could help shift these entrenched preferences.
The Green Nudge:
The Metropia GoEzy travel app provided a platform for testing two types of nudges with 216 participants recruited through social media.
- Experiment 1: Information Nudges – Participants received in-app messages about the societal costs of driving and reminders linked to green identity, while a control group received no messages. This experiment focused on non-habitual trips.
- Experiment 2: Incentive Nudges – Participants were offered small monetary incentives, redeemable for gift cards, if they reduced car use or opted for sustainable transport modes. This experiment aimed at influencing habitual commuting behaviour.
The result: The outcomes were insightful. In Experiment 1, messages highlighting the high societal cost of driving prompted slight behaviour changes, but green identity reminders showed no measurable effect. In Experiment 2, modest financial rewards ($3-$5) successfully nudged users toward intermodal travel but did not significantly reduce car use. Notably, individuals identified as “flexible travellers”—those already using multiple modes of transport—responded best to these nudges. This suggests that focusing on this adaptable group could yield greater success in future sustainable transport interventions.
Are you aware of any other nudges that help to promote green mobility? Feel free to comment or get in touch: hello@green-nudges.com
From Natalia Le Gal, founder of Behava, a consultancy dedicated to fostering change in transport behaviours. Since her first drive in an electric vehicle in 2013, Natalia has been committed to transforming how our transportation systems operate and how people use them.