How global hotel chains can counter light pollution

Light pollution is a serious environmental stressor, affecting biodiversity, ecosystem services and human health. The hotel industry is a major source of it. Unfortunately, so far the “need” to install neon decorations on facades and illuminate swimming pools is winning out over the needs of ecosystems dependent on nocturnal darkness.

A team of Polish researchers representing the Maria Curie-Sklodowska University in Lublin and the Technical University of Lodz has analyzed how the strategies of global hotel chains can help reduce the harmful effects of artificial lighting at night (ALAN) on the environment. The results of the study, published March 8 in the journal Sustainability, suggest that much needs to change in this sector.

The black sheep of the hotel environmental agenda

For years, the hotel industry has been actively implementing many of the demands of sustainability – from reducing its carbon footprint and water consumption to reducing waste. These issues are already part of international certification systems and ESG reporting. However, the sector’s environmental agenda still lacks goals and strategies that address excessive artificial lighting.

Light pollution is a problem directly related to urban development, where most global accommodations are located. Round-the-clock illuminated facades, lobbies and recreational areas are also a hallmark of seaside and mountain resorts, even those surrounded by wildlife. Tourists want to feel safe and luxurious, and hotels cater to their whims at the expense of local ecosystems.

With the lack of legal regulations on ALAN, hotels often operate in a regulatory vacuum, using ubiquitous light to build their brand and prestige. Although Croatia, France, Italy and Slovenia have introduced nationwide standards to limit night lighting, the problem is completely ignored in most countries.

Dark skies as a tourist attraction and financial benefit

Fortunately, the benefits of reducing ALAN are an important decision-making argument for environmentally conscious tourists. There is a growing number of facilities around the world that promise dark night skies overhead – they are often certified by the International Dark Sky Places or Starlight Foundation. Research conducted in 2025 shows that consumers are willing to pay more and travel farther to experience the black night phenomenon.

Dark-sky standards can therefore be part of building an eco-friendly hotel brand image and generate additional profits. At the same time, they fit into the broader trend of nature-friendly tourism and the slow travel movement.

Measures to reduce ALAN are also a way for hotel chains to reduce operating costs. This is especially important in times of energy crisis. Importantly, mitigation measures don’t have to mean turning off the lights altogether, just reducing upward emissions and lowering the color temperature of the lighting.

Leaders or marauders?

Polish researchers analyzed documents from 2024-2025 related to minimizing light pollution at three global hotel chains: Marriott International, Jin Jiang International and Hilton Worldwide. Together, they cover more than 20,000 accommodations in 140 countries around the world. Importantly, as industry leaders, they set environmental standards and policies that later inspire thousands more hotel brands.

Unfortunately, the results are not optimistic. In all three chains, lighting upgrades are seen as a step toward reducing energy consumption and consist mainly of implementing LED technology and automatic control of lights with sensors. Goals such as reducing waste, lowering temperatures and improving the guest experience also appear in corporate strategy documents.

None of the hotel brands surveyed directly address the problem of light pollution or the benefits of protecting dark night skies. The demands for lighting relate only to energy efficiency and minimizing operating costs.

Light pollution a new challenge for the hospitality industry

The contrast between the strategies of hotel chains and the guidelines developed by the Dark Sky International and Starlight Foundation organizations indicates that reducing light pollution is still not yet recognized as part of a corporate sustainability policy. Precise and measurable criteria for outdoor lighting, relating to upward light emission, controlling the temperature of its color and reducing the amount of night lighting, among other things, are already developed, but the hotel industry has so far effectively ignored them.

Barriers to ALAN reduction in the hospitality sector include the huge cost of lighting upgrades, standardization of facilities belonging to global chains, lack of consistent international standards, and uncertainty about return on investment. How can these be overcome?

Polish researchers suggest, among other things, implementing pilot projects in selected destinations to assess the financial and image effects of reducing nighttime lighting, and incorporating light pollution indicators into ESG reporting. Financial barriers, meanwhile, can be reduced by tying dark-sky retrofits to comprehensive energy efficiency improvement programs for lodging facilities.

In the long run, light pollution could be a topic that will spawn great potential. Particularly in the tourism industry, which increasingly appeals to authentic experiences and closeness to nature, turning off the lights could bring a number of benefits. It is worth remembering that ALAN harms birds, insects, turtles and marine mammals, without which many destinations would lose their appeal. Implementing dark-sky principles could prove to be a competitive advantage in the global hotel industry.

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In writing the article, I used:

Iwanicki, G.; Tabaka, P.; Dluzewska, A. The Role of Global Hotel Chains in Mitigating Light Pollution: An Analysis of Corporate Strategies and Regulatory Approaches. Sustainability 2026, 18, 2630. https://doi.org/10.3390/su18052630