What unsustainable behavior needs to change:

Waste from packaging poses a serious environmental problem. The US Environmental Protection Agency reports that there were more than 80 million tons of packaging produced in 2018, with two-thirds of this packaging made of plastic or paper. Once the packaging is no longer in use, some of it is recycled, but much of it ends up in landfills. In 2018 alone, landfilled plastic and paper packaging waste amounted to 10.09 and 6.44 million tons, respectively, accounting for 11% of the total landfilled waste in the United States. 

Despite the potential environmental and financial benefits of reducing excessive packaging, many products remain over-packaged, with layers of superfluous packaging added to the more necessary ones. 

An international research team looked at how consumers respond to such overpackaging, where unnecessary paper is added to plastic. Across eight studies with consumers from the Netherlands, US, and UK, they found that people judge the combination of plastic & paper packaging as MORE eco-friendly than identical plastic packaging without the paper. 

Our brains perceive paper as eco-friendly, while plastic is rather linked to images of polluted oceans. Driven by their biassed environmental friendliness perceptions, consumers are willing to pay more for over-packaged products and are more likely to choose them. 

The Green Nudge:

What unsustainable behavior needs to change:

What do you envision when you think of fast food or food delivery? Perhaps pizza, burgers, tacos, and döner kebab come to mind. While there are increasingly healthier options available, a significant portion of fast food choices still include meat.

A meat-based diet not only harms your health but also damages our planet. It leads to significantly higher CO2 emissions compared to more sustainable dietary choices. Moreover, fast food entails various negative externalities, including excessive fuel consumption for supply and processing, wasteful packaging, food waste, and water contamination. 

But let’s stick to CO2 emissions. A survey conducted by Carbon Trust among 10,000 individuals in 8 European nations revealed that 66% of respondents favoured carbon labelling on products. However, it is unclear whether they are merely professing their support or genuinely acting on their intentions.

The Green Nudge:

The UK-based Mexican restaurant chain, Wahaca, decided to highlight the climate impact by including a carbon label next to each menu item. 

They partnered with Swedish startup Klimato, which calculates and communicates the climate impact of food, to develop a labelling system that uses CO2 equivalents as a base. The calculations include the emissions for growing all the ingredients, as well as those generated when transporting, storing and cooking them.

Wahaca is now using carbon labels in three different dimensions:

• Low carbon (CO2e 0.6kg or lower): i.e. sweet potato burrito (0.46kg)
• Medium carbon (CO2e 0.6kg – 1.6kg): a grilled chicken club quesadilla,
• High carbon (CO2e 1.6kg or higher): such as a chargrilled steak burrito (3.04kg CO2e)

Although we lack concrete evidence in the Wahaca example, showing that highlighting the carbon impact affects food choice, multiple recent studies and trials have indicated that labelling can influence behaviour.

Psychology researchers from the University of Würzburg conducted a study which demonstrated that when individuals were presented with menus containing low-emission options, such as coconut curry with tofu instead of beef, the CO2e emissions decreased by almost one-third. Carbon labelling alone resulted in a 13.5% reduction in CO2e.

Researchers from Johns Hopkins University arrived at similar conclusions. In a randomised clinical trial involving 5,049 adults in the United States, 23% more participants in the high-climate impact label group opted for a sustainable option (i.e., non-red meat), and 10% more participants in the low-climate impact label group chose a sustainable option compared to the control group.

What unsustainable behavior needs to change:

Aotearoa New Zealand sadly isn’t amongst the world champions of recycling. Compared to other countries, recycling rates are much lower. According to Recycling New Zealand, in Auckland alone, the amount of waste sent to landfills is expected to double in the next 10 years!

More numbers? 

• NZ generates 17 million tons of waste each year, while 76% of it goes into landfills 
• 40% of household waste that could be recycled, goes into the wrong bin
• Each year, approximately 2 billion plastic containers aren’t getting recycled

Following the lockdown of the COVID19 pandemic, recycling rates worsened. In Christchurch particularly, rates plummeted, with material from only 48% of garbage collection trucks being recycled in June 2020. The reason: too much contamination resulting from poor sorting by residents. Even the local EcoSort facility had to close temporarily due to  many residents failing to, for example, remove bottle lids or exclude thin plastic films, such as cheese wrappers. 

The question was: How to motivate people to better sort their garbage and keep recycling streams clean? Punishment or reward? Sticks or carrots?

The Green Nudge:

The Christchurch city council introduced a public reward (and shaming) system that builds on the idea of social norms. Anyone who does an excellent job at sorting the right, properly cleaned rubbish items gets a large gold star added to their kerbside recycling bin, visible for the whole neighbourhood to see. The star uses a neat pun, saying: “Thanks for bin great”. 

The result: In 2020, more than 177,000 bins have been checked, with nearly 50,000 gold stars issued (~31%). They not only rewarded successful recyclers – compliance staff also gave out education notices (to ~61%) and removed the bins of those who repeatedly failed to recycle properly (only ~260 in total). The council considers the Green Nudge initiative as a great success: In only a few months, the number of successful recycling trucks headed to the sorters increased from 48% to 80%.

So, what are the underlying reasons that the nudge worked? We’ve seen other social imitation nudges like in the energy supplier or shopping trolley examples. But the gold star stickers are more visible on a public level and have a stronger shaming element.

MIT research scientist Erez Yoeli, who studies how altruism works, would probably explain this as ‘our collective desire to be seen as generous and kind instead of being selfish’. But Kenrick and Griskevicius might argue that “going green to be seen” might indeed be status-driven social signalling and thus be anything but altruistic.

Full article in The Guardian.

What unsustainable behavior needs to change:

Let’s start with two questions:

1. What is the recommended daily amount of veggies you should consume in order to follow a healthy diet?
2. How many people actually meet the daily intake of vegetables

To speak for the Netherlands, only 6% of people aged between 1-79 years consume the recommended daily amount of 250g of veggies. The German nutrition organization even recommends eating 400g veggies and 250g fruit per day. But as only 13% meet the recommendation, the organization started the “5 per day” initiative to promote a healthy plant-based diet. It should be no surprise to find similar data in other countries. 

Why should we care? Besides the comparably higher CO2 emissions that come with meat-based diets and the lack of animal welfare, an inadequate vegetable consumption is a public and individual health concern.

So how can you nudge someone to make more healthy food choices such as veggies?

The Green Nudge:

Supermarkets can have a considerable impact on people’s food choices. In a 2020 quasi-experiment in a Dutch supermarket with 244 participants, researchers tested two Green Nudges that used the idea of social imitation. 

The researchers put inlays in shopping trolleys that 

a) communicated a social norm message about vegetable purchases and
b) showed a designated place to put vegetables

The result: 73.3% of people noticed the green inlay in the shopping trolley. The social imitation intervention led to a statistically significant increase in grams of vegetables purchased. This was especially true for people who bought groceries for less than three days, which could be explained by a more impulse and thus more influenceable behaviour.

Social scientists have demonstrated the influence of peer behavior in a host of areas. We’ve been building bigger houses, driving heavier vehicles, flying to remote destinations or engaging in a host of other energy-intensive activities. A dominant reason we are doing these things is our tendency to behave as our peers do. But experiments like this give reason to believe that peer effects could be similarly beneficial to our climate future and individual health improvements.

Full article in ScienceDirect.

What unsustainable behavior needs to change: Well, I confess it: I used to brush my teeth during a long, hot shower. It just felt comforting and self-indulging. But it started to feel wrong- to waste so much water and energy. But wait, was it a lot? How much water and energy is needed for a shower? Does it make a big difference if I shower for 2, 5 or 10 minutes? I had no clue, because it was too abstract. 

In most households the shower is the 2nd biggest energy consumer (after heating). In Germany, people spend between 8-12 minutes under a running hot shower with 40°C (104°F). That means approximately 20% of the total energy used to heat water and ~16 liters of water per minute. 

In order to saving energy, we could either shower shorter or reduce the temperature of the water. The first problem here: showering is extremely habitual and the shower is also the place where your mind wanders and you forget time easily. The second problem: although reducing the temperature by 2-3°C would make a difference, guessing the temperature is as inaccurate as trying to hear the decibel of a winter car tire. 

What we need is a feedback mechanism that makes the abstract energy and water consumption more concrete, more salient. Something that nudges people into shorter and colder showers.

The Green Nudge: Swiss company Amphiro came up with a digitally enabled behavioural intervention: a smart shower meter that provides real-time feedback of your energy and water consumption during the shower. 

Researchers from the ETH Zürich and the University of Bamberg conducted a natural field experiment with an uninformed sample of guests at 6 Swiss hotels (265 rooms, N = 19,596 observations). 

The rooms were equipped with smart shower meters in their hotel rooms. The devices measured the energy and water consumption of every shower taken, and displayed feedback on each ongoing shower in real time. 

Information that was shown on the display:

• total water consumption in liters, 
• total energy use in kWh, 
• a dynamic rating of the current energy-efficiency class (A–G) and 
• a four-stage animation of a polar bear standing on a gradually melting ice floe 

The result: a large and significant energy-conservation effect of 11.4% or 0.215 kWh per shower (vs control group that was shown only temperature).

While this does not fully translate to household settings, it demonstrates that feedback can be an impactful nudge to preserve resources like energy and water. Especially when you scale this up for a larger group.

Full article in Nature.

What unsustainable behavior needs to change: In 2013 when the Green Party in Germany demanded a veggie/vegan day in company, school or university canteens, the outcry was massive: “Cancel culture.” “Don’t take away our freedom!” “Political paternalism!”. The idea was not only to create awareness for a diet with less meat but to directly reduce emissions.

However we need to recognize that meat consumption is a big driver for CO2 emissions that expedites  global warming. Western Europeans eat 10x more meat than people living in India. Eating meat has societal as well as personal consequences: A fat-heavy diet often leads to obesity and severe health issues like heart attacks.

The problem: most often the negative externalities of meat consumption are hidden. Most people don’t know how much CO2 emission their steak is responsible for how a meat dish compares to a veggie option.

So the question is: how can we become choice architects that just nudges a decision instead of telling people what to do.

The Green Nudge: In a joint effort the Ludwig-Maximilians-Universität München, Humboldt-Universität zu Berlin and the Aalto University wanted to examine if making negative environmental impacts like CO2 emissions more salient, would nudge people to adapt their choices.

In a 10 day field experiment in one of the biggest university canteens in Munich with over 8.000 visitors (during that 10 day time period), the researchers introduced menu displays showing the food option but also the environmental externalities like the CO2 footprint

The interesting bit: their experimental design included testing different options of how to visualize the negative footprint.

Variables were:
➡ the negative cost in €
➡ the amount of an individual’s daily CO2 budget spent
➡ the amount of CO2 emissions

They introduced traffic light colors: green for dishes with low CO2 emissions, yellow for more emissions and red for the “climate-killer-lunch”.

The result: the demand decreased for CO2-intensive choices with meat and fish and thus reduced the footprint of the total lunch menu. The researchers could observe the biggest effect when visitors learned how much environmental cost (in €) their lunch would cause. So making something intangible more salient resulted in almost 10% less CO2 emissions compared to days when they didn’t show any negative environmental impact on the menu displays.

What unsustainable behavior needs to change:

According to the Waste Resources Action Programme (WRAP) we waste a staggering amount of 88 million tons of food every year because of the expiration date. So, we are wasting food only because a print on the product says it has reached its end of shelf life- even if it was still good to consume.

The thing is: it’s often hard to say if food has gone bad or not. Of course there is the good old: “Look, smell, taste” but obviously this proves difficult for packaged food. It is hard to tell if food is safe to eat beyond the expiration date, unless you see some nasty mold on it. The process of decay is extremely abstract and people – when in doubt – prefer to  play it safe and throw it away. This is not only valid for people in front of their fridge. For retailers, it has a significant cost effect. When a product nears it’s expiration date, it often will go on discount or is thrown out. 

So one tool to reduce food waste would be something that makes the abstract more concrete. Some mechanism that extends the product and shelf life. If only the food or packaging could talk and stop this unsustainable behaviour.

The Green Nudge: To address this challenge, salient feedback can be a great nudge to trigger action. Feedback coming from the product. More precisely: from the packaging. 

London-based start-up Mimica came up with a game-changing, bio-inspired packaging innovation. Their Bump products are temperature-sensitive, dynamic expiry labels for food or beverages. The labels – coming a tag or cap – contain a gel filling that goes from smooth to bumpy at the same pace as the food inside deteriorates. This way they provides accurate, real-time feedback of the product’s freshness with a tactile interface. 

Mimica founder Solveiga Pakštaitė was inspired by the banana skin transformation which changes its colour and texture as it ripens. One of nature’s great ways to provide feedback: green = don’t eat, yellow = eat, turning brown = hurry, it will go bad soon.