Human decision-making of environmentally friendly products is more complicated than you think. Insights from cognitive sciences can help marketers and entrepreneurs to understand green consumer behaviour.
Green behaviour describes how one acts to minimise harm to the environment as much as possible . So, it is expected that individuals adopting green behaviour would buy pro-environment brands.
However, there is a significant gap between intention and actual purchase. A study has reported that in the United States despite 65% of individuals saying they want to have environmentally friendly behaviour, only 26% do so . Many variables (e.g. gender, lifestyle and socio-economic status) affect consumer choice, but both human behaviour and decision-making are at the centre of climate-change and consumer psychology. Therefore, companies that apply behavioural sciences to business strategies can increase green consumer behaviour.
Below are a couple of reasons that influence green consumer behaviour , thus affecting the intention-actual purchase gap. Bear in mind, this is by no means an exhaustive list, but it is a starting point for both marketers and entrepreneurs.
The human brain prioritises experience over analysis.
There is no doubt climate change is a threat, and we should prepare for it. However, scientists rely heavily on statistics and mathematical models to study climate changes (e.g. precipitation patterns, long-term changes in temperature). As a consequence, media channels have no other option but to communicate climate changes using analytical formats, which might seem too abstract and confusing to the general public. This is problematic because, in doing so, media channels assume that viewers are comfortable with analytical reasoning. However, this is not the case.
Cognitive psychology research  has revealed that the human brain relies on two distinct processing systems commonly known as system1 (fast, intuitive and automatic) and system2 (slow, deliberate, effortful). For instance, the brain activates system1 when a person tries to decide between two chocolate brands— a reasonably straightforward problem. In contrast, the brain activates system2 when a person tries to infer how his or her consumer behaviour would affect global climate change for the next 100 years— a complex problem which results in a high cognitive load. However, both systems run in parallel to guide human decision-making with frequent disruptions (also as a consequence of high cognitive load), causing system1 to take over and make complex and abstract decisions that should be made by system2. As a consequence, the lack of reason and logic to complex problems lead human decision-making to biased behaviours (e.g. the repeated purchase of a not eco-friendly product) maintaining the status quo. These findings suggest that to create green consumer behaviour, brands cannot rely solely on statistical arguments and specialists’ advice (e.g. international certificates) as a critical part of their marketing strategy.
Moreover, research shows that emotions affect rational decision-making  and that negative emotions, such as feeling at risk, are the most reliable indicators of climate-change perception . These findings applied to consumer psychology suggest that how a person feels when shopping affects his or her consumer behaviour. Therefore, your risk perception of how climate-change affect your life may draw the line between analytical and experiential consumer decision-making. The brain often prioritises experience over analysis. Thus, translating the risks associated with climate-change into relatable and personal experiences, i.e. tapping into one’s emotions, is an effective strategy to encourage green consumer behaviour.
Humans respond to social norms.
Given the global impact of climate change people’s self-efficacy (i.e. the belief that independent personal actions can make an impact) is quite low . So, at times, consumers feel powerless and continue buying not eco-friendly products instead of adopting green behaviour. Interestingly, humans have evolved as social beings, as living in groups has provided evolutionary advantages . So, it is not a surprise that individuals often seek social confirmation of their opinions and decisions . For example, Instagram users may validate their behaviour and views by the number of ‘likes’ each photo has.
Researchers  reported that following the norm is a common practice in group-living species because it reduces the costs of learning. So, if ‘everyone’ is reducing single-use plastic bottles, then it must be the ‘right’ thing to do. This is a perfect example of how your system1 decides to buy a Boxed Water or an aluminium bottle to carry around without a significant cognitive load. Nevertheless, system2 should make an effort to estimate how many plastic bottles, on average, an individual buys in a lifetime, then infer its impact on the planet, and conclude that aluminium bottle is preferred over single-use plastic bottles. As you might have expected, social norms play an important role in green consumer behaviour.
Moreover, psychologists  have demonstrated that normative messages are potent ways to change [green consumer] behaviour. In the study, when people are informed of their neighbours’ average energy consumption, they tend to adjust their energy consumption to follow the group norm. So, perhaps by rewarding green consumer behaviour at the social level, more people are likely to conform, which would sustain green behaviour, and increase general self-efficacy against climate change.
Green consumer behaviour has the power to make a positive impact on the environment, but the intention-actual purchase gap sustainable products are still massive. The human brain, in most cases, prioritises relatable experiences over abstract analysis, and social norms are effective ways to raise awareness of new green behaviour. Therefore, cognitive psychology research can shed light on how marketers and entrepreneurs should promote sustainable brands.
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