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

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

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

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

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:

1. Positive-framed message: Featured a green, bright background emphasizing benefits like “help protect the environment” in the call-to-action.
2. Negative-framed message: Featured a dark background highlighting consequences like “help stop the collapse of the environment.”
3. 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

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: 

1. By displaying a sentence at the top of the screen while participants answered a survey; 
2. By asking participants to write a brief essay reflecting on the feelings associated with a real future decision; 
3. 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

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

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

What unsustainable behaviour needs to change:

Gum litter remains a persistent issue—sticking to pavements, clinging to shoes, and proving notoriously difficult to clean. Its non-biodegradable composition, usually a blend of synthetic rubber and plastic-like polymers, takes 20–25 years to break down, leaving microplastics that pollute soil and waterways. Additionally, cleaning gum off streets requires intensive methods that consume water, energy, and often involve chemicals. This litter also negatively impacts wildlife, as animals may ingest gum or get it stuck on their paws or fur, leading to health issues and harm to urban and natural ecosystems.

In collaboration with Mars Wrigley and the gum industry, targeted interventions were developed to encourage proper disposal and reduce environmental impacts.

The Green Nudge:

Many people believe gum littering is caused by a small group of antisocial individuals. However, ethnographic research by Behaviour Change showed that context, rather than character, often determines littering. Most people don’t drop gum habitually, but certain situations increase the likelihood of littering. Researchers identified six of these high-risk circumstances and designed behavioural interventions accordingly.

In one workshop, participants expressed concern about animals getting stuck in gum, leading to the development of the “cute kitten” intervention. Using the ‘affect heuristic,’ the design featured a kitten on signs and stickers placed strategically on bins and lampposts to leverage emotions and humour, effectively reminding people to dispose of gum properly.

The result: A 9-week evaluation measured gum littering rates before and after the intervention, using highly accurate gum counts adjusted for footfall using mobile phone data. The “kitten” signage reduced gum litter by up to 61%. When paired with a preliminary gum cleanse, the combination achieved an 80% reduction in gum littering.

Do you know of any other nudges that prevent gum littering? Feel free to get in touch: hello@green-nudges.com 

What unsustainable behaviour needs to change:

In both the U.S. and Europe, residential electricity remains largely fossil-fuel dependent, with 60-65% coming from natural gas, coal, and oil. While Europe has reached around 35% in renewable electricity, the U.S. trails at less than 20%. Solar adoption in single-family homes is limited to only 4.4% in the U.S., while European countries like Germany and Sweden see a higher uptake due to renewable-friendly policies.

This dependence on fossil fuels persists partly due to a key barrier: the benefits of solar power often feel intangible. Many homeowners struggle to commit to renewables without clear, concrete insights into potential cost savings and environmental impact.

The Green Nudge:

Google Maps‘ Solar Potential API, launched in August 2023, tackles this barrier directly. Using aerial imagery and advanced data analysis, it estimates the sunlight each rooftop receives and calculates personalised energy savings and carbon reduction potential. As a trusted platform, Google Maps transforms solar energy’s abstract advantages into clear, actionable information.

This API provides detailed insights into the solar potential of rooftops for over 320 million buildings across 40 countries, factoring in sunlight exposure, roof shape, shading from surrounding structures, and local weather patterns. This personalised data empowers homeowners to consider solar power as a feasible, impactful option, with both financial and environmental rewards.

The result: Though its widespread impact is still unfolding, initial indicators show increasing interest in solar power among homeowners. Over time, this tool could significantly reduce household reliance on fossil fuels, especially in regions with robust renewable policies, thereby lowering emissions and accelerating the adoption of clean energy solutions.

Are you aware of any other nudges that help drive the sustainable energy transition? Feel free to get in touch: hello@green-nudges.com