- Consumers are increasingly shifting to more sustainable food options but a lack of clear information on the climate impact of individual products is hindering this transition.
- Carbon labels present a viable option to deliver greater climate transparency. The purpose of this study is to assess the impact they have in influencing consumer decisions.
- At Microsoft’s UK Headquarters, in partnership with BM caterers, we ran a 4-week period where carbon labels were displayed, and compared the sales data of these meals against the previous 4-weeks, when carbon labels on the exact same meals were absent.
- Across a monthly total of ~2200 transactions, we found a total drop in emissions of 6.5% when carbon labels were present, and the average emissions per meal choice decreased by 4.85%. Most notably, sales of the lowest environmental impact meals rose by 50%, and sales of the highest environmental meals dropped by 18.5%.
- These results conclusively show that the presence of carbon labels influences consumers to choose meals with a lower environmental impact. From this investigation, it can be said that carbon labels are a cost-effective and viable tool that can be used to encourage more sustainable food choices and should be implemented permanently and across more locations to scale up their impact.
- Labels should also be used in conjunction with incentivisation tools that add tangible benefits to choosing lower products. The Reewild app uses a gamified model to encourage users to track their overall consumption, building in a system of recommendations and incentives to entice users towards greener options, including monetary incentives. By making sustainability more engaging, consumers can consistently strive to lower their carbon footprint in a more systematic manner.
The food industry produces around a third of global emissions. To mitigate climate change and prevent a catastrophic raise in global average temperature, the sector needs to wholly prioritise the reduction of carbon emissions. It has never been more important to be transparent about the environmental impact of the food we produce and accordingly, this is becoming an area of increased focus for shoppers, businesses, and governments alike.
Increasingly, consumers are shifting their buying choices to focus on the sustainability of goods, but rarely benefit from reliable and universally recognised information to guide those choices. To help consumers, and combat greenwashing, the UK’s Green Claims Code does now require businesses to take accountability for their environmental impact and back up any sustainability claims they wish to make. However, a universally adopted system to identify the climate impact of products has yet to be rolled out in the UK.
Carbon labels present that option - a way for consumers to quickly identify the sustainability of any one product, and a means for companies to become Green Claims Code compliant. The aim of this study is to prove that carbon labels influence consumer choice. We hypothesise that, based on the presence of carbon labels, we will see more consumers change their choice of meal to a product that generates lower emissions. This in turn will reduce the combined overall emissions of all the meal choices.
When carbon labels have been trialled previously, the average emissions of a meal choice dropped by 4.3% when carbon labels were present. This gives us confidence that on average, more consumers would opt for a lower emissions product given the choice.
The majority of Europeans support the introduction of carbon labels (72%). However, in reality, there is still a lack of understanding on how consumers are influenced by the physical display of environmental data. We want to continue to address this gap in information, by carrying out an empirical pilot study with the potential to scale up to prove that carbon labels are an important factor in reducing the emissions of the food industry. By giving consumers the power, we hope it will force faster environmental change within the sector.
- Calculate the carbon emissions of each unique product involved in the study.
- Measure changes in consumer behaviour using carbon labels that display the carbon emissions of each product.
- Measure any changes in emissions as a result of carbon label-influenced consumer behaviour.
At Microsoft UK’s headquarters in Reading, the investigation ran over 8 weeks, with the first 4 weeks set as the control period where carbon labels were absent (Absent Period), and the last 4 weeks set to display carbon labels on the restaurant’s menus (Present Period). A comparison can be made between the two 4-week periods, since the restaurant uses a 4-week repeating rota of the same meals. The study, done in partnership with BM caterers, ran from 5th September 2022 to 28th October 2022. Meals were given a carbon score based on their preparation and composition, considering the weight of each ingredient within each meal. The carbon scores were calculated using the Foodsteps platform. The idea was to keep the investigation as simple as possible, so the only variable was the presence/absence of carbon labels.
Carbon label categorisation and design
Carbon labels were based on the carbon emissions of the overall meal. The meals were assigned to an environmental impact category from A-E based on the value of emissions. Table 1 below outlines the categories and the associated colours and values.
After carbon scoring the menus, 92 meal variations were served in the Absent Period, and these 92 were then repeated in the Present Period. The distribution of these meals across impact categories can be seen in Table 2. The mean carbon score for the meals was 2.62 kg CO2e per serving.
Sales data for each meal was collected over the 8 weeks, to account for consumer choice. We were able to directly compare 92 meals between the two periods.
In the Absent Period, 2260 individual sales of the 92 meals were made. In the Present Period, 2221 individual sales of the 92 meals were made. There was an overall emissions drop of 6.5%, from 7,236kg CO2e to 6,766kg CO2e. This equates to a reduction of 470kg CO2e per month with the presence of carbon labels, when compared to the absence of carbon labels.
The average emissions per meal choice was 3.20kg CO2e during the Absent Period. This dropped by 4.85% to 3.05kg CO2e during the Present Period.
When examining the variation in sales within Impact Categories, there was an increase in sales of A (Very Low impact) and B (Low impact), most notably a 50% increase of A category sales. There was a decrease in sales of C (Medium impact), D (High impact), and E (Very High Impact).
The drop in emissions of the two highest impact categories - D and E - were 3.95% and 19.8% respectively. Table 3 below outlines the change in emissions from each category based on sales made.
These results are fully aligned with the hypothesis, showing that the presence of carbon labels correlates to a reduction in the average emissions per meal choice. The numbers presented in this study are similar to those laid out in the Lohmann et al. (2022) large-scale study of carbon labels in university cafeterias, adding to the evidence that carbon labels do in fact influence consumers to choose meals with a lower environmental impact.
When extrapolated, a reduction of overall emissions of 6.5% would equate to a yearly reduction in emissions of over 5.5 tonnes CO2e in just one canteen. This shows that implementing carbon labels can be part of the larger Net Zero strategy of a business.
The most notable result was the consistency of the pattern across Impact Categories. The increase in purchase of Very Low and Low environmental impact meals, and the decrease in the purchase of Medium, High, and Very High environmental impact meals, shows across the board that consumers were actively choosing meals with lower impacts whilst avoiding the highest impact menu items. This means that the presence of carbon labels was nudging consumers towards more sustainable choices. The largest changes in sales came from the A and E categories. The results show a coherent move from higher impact meals to lower impact meals.
From this investigation, carbon labels are a cost-effective and viable tool that can be used to encourage more sustainable food choices. They can also lower the overall emissions of business practices by utilising the power of consumer choice. If the impact of this study is scaled up to all 221,000 of Microsoft’s employees, the decrease in the average emissions per meal over one month (assuming all employees dined in the restaurant each day) would equate to almost 1,000 tonnes CO2e reduced. If carbon labels were mandated across the UK, the industry’s footprint could be reduced by almost 17,500 tonnes each day (a 4.85% reduction to the average UK diet footprint of 5.17kg CO2e). We conclude that carbon labels should be implemented permanently and across more locations to scale up the impact they can have in reducing carbon emissions whilst leading to a sustainable shift in consumer behaviour.
Building in incentives
Carbon labels provide a strong starting point for greater climate transparency, but there are more tools that can be deployed to incentivise the choice of lower impact products.
In a recent Italian study, the presence of carbon labels showed a similar result to our investigation (a 7% decrease). However, they went one step further, by associating a personal benefit with the carbon labels, such as improved health, cheaper price, or energy savings, which led to a further 22% shift to lower impact meals. This shows that a combination of factors goes a long way in increasing the uptake of more sustainable choices.
The Reewild app is a tool that can empower this extra 22%. By using a gamified model, the platform encourages users to track their overall consumption, building in a system of recommendations and incentives to entice users towards greener options, including monetary incentives in the form of offers and discounts. By making sustainability more engaging, consumers can consistently strive to lower their carbon footprint more systematically. According to a recent study, 83% of workers think that their employer is not doing enough to tackle climate change. Carbon labels and the Reewild app provide an effective and visible approach to change perceptions while having a marked impact on emissions.
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