Julie de Vaan
How can we increase the effect of the deposit on small plastic bottles?
Updated: May 12
One year after the introduction of a deposit on plastic bottles in the Netherlands, 80% of all plastic bottles sold are returned for a deposit (NOS, 2022). The organization 'Statiegeld Nederland' indicates that it is not dissatisfied with the results. Nevertheless, the target of 90% in 2022 has not yet been achieved and there are some critiques. For example, is (the behaviour of) the consumer taken into account?
If we look at behaviour, the introduction of deposits pushes a few important buttons that can determine whether or not we dispose of our bottles correctly. However, the deposit is not always the decisive factor. There are also many other factors that sometimes have more influence on the choices people make. So, what else do we need to do to increase the effect of the introduction of deposits and to ensure that the target of 90% is achieved by 2022?
Why do or don't we hand in our plastic bottles correctly
First, let's take a look at how behaviour comes about. There are roughly 5 reasons why we hand in our small plastic bottles the right way:
Attitude: because we think it's important to return the bottles the right way.
Motivation: because we are motivated to return the bottles the right way.
Perceived efficacy: because we feel like it is effective and useful that we do it.
Convenience: because it's easy.
Social Influence: Because we feel like it is normal and it is expected from us.
The way in which the choice of whether or not to return deposit bottles is made depends on the situation. Depending on the target group, for example: is it very positive about waste collection and separation or does it find it less important? Or depending on the location: is it possible to return plastic bottles there, or do we have to return the bottles elsewhere?
Do you want to encourage as many people as possible to return their bottles correctly as often as possible? Then try to push all the buttons: attitude, motivation, perceived usefulness, convenience and social influence. Do you want to change behaviour in a specific situation (for example with a specific target group or in a specific location)? Then try to push the buttons that are the most important in that situation.

The effects of the introduction of a deposit
On the one hand, the introduction of a deposit has a positive influence on attitude, motivation and perceived efficacy. People are getting the feeling that plastic is a valuable renewable resource and that it is therefore important to return it in the right way. In addition, the direct, personal and short-term effects of handing in become clearer. People therefore get the feeling that handing in empty plastic bottles in this way is effective and yields something. This increases motivation and perceived efficacy.
On the other hand, the introduction of a deposit can also have a negative influence on attitude and perceived efficacy. Emphasizing a (small) financial incentive can ensure that people who are not sensitive to this do not see the usefulness of collecting and returning their plastic bottles. "I don't need that 15 cents anyway." In addition, the correct return of plastic bottles will become less easy due to the introduction of a deposit. It is not always clear which bottles contain a deposit and which do not, and having to collect and return bottles at the supermarket takes more effort than throwing them in the plastic waste bin or bag.

How do we increase the effect of the introduction of deposits?
To ensure that even more people hand in their plastic bottles even more often, we can push the important buttons even better. How?
By also discussing the consequences for the environment. As a result, in addition to the financial incentive, the importance for the environment also becomes relevant. People who (want to show that they) are not led by a (small) financial reward then have at least another reason to hand in the bottles correctly. This reason stems more from intrinsic motivation and its effect is often longer lasting than the introduction of a reward. In addition, by emphasizing environmental reasons to return bottles, you can also count on more understanding for the introduction of a deposit. For example, it is good that some attention is already being paid to this in the new part of the campaign around deposit bottles: “Hand them in! Better for the environment and you get your deposit back”.
By making it easier to return plastic bottles. For example, by making it possible to hand them in in more different places. And if it is not possible to physically increase the convenience, then increase the feeling that the behaviour is easy and achievable. For example, by creating clarity about which bottles should be returned for deposit and which not. Or by giving people the feeling that only a very small action is expected of them, and by showing what a big result this yields.
By cleverly responding to social influence. With the slogan “We don't throw away small plastic deposit bottles”, the campaign around deposit bottles is already setting a social norm. This is even more effective if we ensure that this message comes from multiple sources. Sources that appeal more to the target group, for example because they connect to the target group or are physically close/present (for example the local football club that addresses the fans in or around their own stadium).
So, in short:
The introduction of a deposit on small plastic bottles ensures that:
We become more aware of the value of plastic,
We are more motivated to actually hand them in in the right way,
And that we see more use of this.
In order to increase the positive effect of the introduction of a deposit, we must also ensure that:
The positive consequences for the environment are emphasized,
Returning bottles becomes easier,
And a clear social norm is set by parties that are relevant to the target group.
This way, we can ensure that even more plastic bottles are returned correctly and that the sustainability goals are achieved.
Sources:
NOS. (2022). After one year of deposits on small bottles: 80 percent returned, target not yet achieved.