You’d think that this gentle reminder would inspire guests to be more eco-conscious. But Professor Sara Dolnicar from the University of Queensland, a social scientist dedicated to the study of sustainable behavior, has discovered the opposite: “These signs simply don’t work.”

She says guests on vacation have given themselves a “license to sin.”

”They’ve worked hard all year, separated their trash into the correct bins every day and remembered to turn off the lights each time they left the house,” she tells me in a video call.

On vacation, they feel like they deserve a little break. For a short period of time, they are prioritizing their own comfort and indulgence over sustainability.

For the past decade, Professor Dolnicar has studied and field-tested methods to encourage consumers, particularly tourists, to adopt more sustainable behaviors.

While making people save energy at home is relatively straightforward—thanks to the direct impact on their energy bills—doing so in a hotel environment, where guests have no financial incentive, presents an entirely different challenge.

“If I can crack tourism, I can crack anything,” she says. ”Especially luxury tourism, given the high expectations and attitudes of this market segment.”

The First Method: The Power of Peer Pressure

One approach that has shown promise is leveraging social norms—the perceived and mostly unwritten rules of behavior within a group—through peer pressure.

Especially when it comes to food: Studies have found social influences on eating to be powerful and pervasive. Our food intake is different when we are with others compared to when we eat alone.

“That’s why people tend to overfill their plates at a buffet. They think others are watching them and judge them if they go back multiple times to get more food,“ says Dolnicar.

An experiment conducted by researchers placed an elegant sign on each restaurant table with the message: “Welcome back! Again! And again! Visit our buffet many times. That’s better than taking a lot once.” The subtle shift in social expectations eliminated what was previously perceived to be embarrassing (returning multiple times) and led to a 21% reduction in food waste. Without mentioning an environmental benefit or food waste—just a straightforward correction of social norms.

Second Method: Nudging Guest’s Behavior

Another highly effective strategy to affect the way we behave is nudging, a concept popularized by behavioral economists and now embraced by governments worldwide.

Nudging involves subtle changes in how choices are presented, such as making sustainable options the default choice.

In one study, the simple act of reducing the size of plates at a buffet by three centimeters (slightly more than an inch) resulted in a 20% reduction in food waste. “It’s an infrastructure change. You don’t even need to communicate anything to the guests,” says Dolnicar.

Nudging can also significantly reduce room cleaning frequency. In a city-center hotel primarily serving business travelers, Dolnicar’s team changed the default from daily cleaning to no cleaning unless requested.

This change resulted in a remarkable 63% reduction in room cleaning, benefiting both the environment and the hotel's operational costs. Since this service constitutes a significant portion of a hotel's expenses, the reduction translates into substantial financial savings.

The Method With The Most Impact: Enjoyment

However, Dolnicar’s favorite approach—and the one she says holds the most promise—is linking sustainable behaviors to enjoyment: “Tourism is all about pleasure, so why not integrate fun eco-friendly actions into the vacation experience?“

Her team introduced a simple stamp collection game in a European family hotel. Families received a stamp for each meal where they finished all their food, with a prize awarded at checkout.

The result was a 38% reduction in food waste. “Kids went crazy for it,” she says, emphasizing that the focus was on enhancing enjoyment rather than addressing the benefits for the environment.

Dolnicar also has ideas how the enjoyment method can be applied to luxury hotel buffets. “An easy option would be small markers pointing out the healthiest food options.” Guidance, she says, makes consumers less likely to overfill plates.

Housekeeping is another area where the enjoyment method can save money and increase eco-friendly behavior, especially in luxury hotels. Since wealthy guests place “ultra-privacy“ at the top of their priority list, as Internova Travel Group has found, they are more receptive to initiatives like a default change in room cleaning.

In a field experiment Dolnicar and her team placed signs in hotel rooms, stating: “We value and respect your privacy, so we will not clean your room daily, but will happily do so upon your request.“ It’s a subtle communication of hedonic benefits: guests get freedom of choice, flexibility and well-deserved privacy.

Recommendations to Implement The Methods

Despite the clear benefits, Dolnicar says many hotels struggle to implement these strategies effectively. “Hotels often have very silly ideas,” she says, “I’ve seen hotels put table signs in 10-point font and half an essay written on them. Nobody is going to read that.“

Without a background in behavioral science, she says they might miss crucial details or introduce elements that backfire. This is why she emphasizes the importance of following proven solutions or consulting with experts.

“There are so many good solutions that have already been tested,” she says. The key is to understand the guests’ mindset and find interventions that align with their values and desires.

Whether hotels decide to use peer pressure, nudging, or enhancing pleasure, the path to eco-friendly tourism is to make it easy, make it enjoyable, and most importantly, make it feel natural.

Katharina Kotrba

Contributor

Business Journalist covering high-end, unusual luxury travel spots