AI is leaving its mark on our environment, climate and landscapes

Opposition to data centres is growing

AI is processed in data centres just like all other internet-related activities. As global consumption of AI increases, more new data centres are being built to meet demand. But the data centres' high electricity and water consumption is meeting growing resistance.

According to the British news outlet The Guardian, at the end of 2025, more than 230 environmental organisations in the United States, including Greenpeace, joined forces in calling on the US Congress to halt the construction of new data centres in the country. The centres' resource consumption is too high and is putting pressure on American households with rising electricity prices and challenging regions where water is a scarce resource, according to the protesters' argument.

Indeed, there are indications that the taps will need to be turned on when developing AI. One example is the large language model GPT-3 (the precursor to ChatGPT), which was developed by OpenAI. According to calculations by American researchers, the development consumed millions of litres of fresh water when it was trained in Microsoft's data centres around the world. The water was used, among other things, to cool the data centres.

The same researchers estimate that global demand for AI is expected to increase so much that annual AI water consumption in 2027 will reach 4.2-6.6 billion cubic metres. According to the researchers, this is more than the total annual water consumption in Denmark.

More data centres in Denmark

The challenge of cooling data centres and obtaining sufficient power is prompting several players to seek new solutions. One of the more radical solutions can be found at Google, among others, which is considering establishing data centres in space, where it is quite cold and there is abundant access to solar energy.

Here on Earth, the focus is currently on northern latitudes, where the cooler climate makes establishing data centres an attractive solution. Denmark is also experiencing growing interest from companies that want to build data centres. In December 2025, Microsoft announced that it intends to build three new data centres in Jutland over the next two years. The company is already in the process of building three centres on Zealand, which are scheduled to be operational in the first half of 2026.

Currently, no Danish authority has an overview of the number of data centres on Danish soil, and there is no definition of when an infrastructure can be called a data centre. When asked, the Danish Agency for Digital Government is therefore unable to provide any precise information about the number of data centres in the country.

However, the company Data Center Map has an estimate. The company is a kind of international ‘data centre broker’ that connects data centre providers with customers who need them. Their website stated in the beginning of 2026 that Denmark hosted 81 data centres.

Data centres will consume a third of Danish electricity in 2050

Today, data centres on Danish soil consume 2 terawatt hours (TWh) annually, according to the Ministry of Climate, Energy and Utilities. They predict that electricity consumption will increase significantly in the coming years. In the report “Climate Status and Projections 2025”, the ministry writes that data centres' electricity consumption is expected to reach 8 TWh in 2030, and by 2050, consumption will be as high as 26 TWh. This means that in just under 25 years, data centres in this country will account for one third of Denmark's total electricity consumption, according to the report.

However, not all of this electricity will be used for pure AI nonsense, as the technology has long been an important tool in research environments, among other places, points out Søren Hauberg.

"AI is a technology that can lead to huge gains for our society, and it has enormous utility when we use it correctly. For example, when researchers are looking for specific genes in bacteria to use them for health-promoting purposes, or if you want to develop new materials that can make Power-to-X more efficient, AI can help us find new solutions much faster," says the professor, who elaborates:

“It is an interesting dilemma that we have to use a resource-intensive technology such as AI to achieve a society that uses fewer resources.”

Alarmists versus optimists

This is a dilemma that is also being discussed among international researchers working with internet and communication technologies (ICT), says Professor Leif Katsuo Oxenløwe. He heads the High-Speed Optical Communications research group at DTU Electro, where researchers are working to make ICT more energy efficient so that the technologies become more climate friendly. The professor admits that the increasing use of artificial intelligence is contributing to ICT's climate footprint.

In the autumn of 2025, Leif Katsuo Oxenløwe helped organise a conference on optical communications with 8,000 researchers in Copenhagen, where the climate impact of ICT was discussed.

"Part of the debate is about whether the internet is good or bad for the climate. I myself am in doubt, because you can find studies and calculations that point in both directions, and part of the debate at our conference focused on how we need to acquire more knowledge to get a better overview of ICT's climate footprint," says Leif Katsuo Oxenløwe.

He explains that the debate is characterised by two camps: the alarmists, who believe that ICT is a climate sinner, and the optimists, who point out that internet technologies are replacing processes that would have had a greater impact on the climate and the environment. The professor refers to the organisation Global Enabling Sustainability Initiative (GeSI), which has calculated that the internet compensates for its own weight in CO2 one and a half times over. Although GeSI's work has since been criticised for only including the best cases, the point is as follows:

"Before music services such as Spotify and other online solutions, we bought music on CDs. The production of these and their physical distribution across the globe also had a climate footprint. So today, when you stream music and use the energy and resources that the internet is based on, equivalent to 1 kg of CO2, you have actually saved 1.5 kg of CO2 because we avoid the production and distribution of CDs," says Leif Katsuo Oxenløwe.

Invisible resource consumption

AI services that generate images of banana-eating clowns or help us write party songs are unlikely to replace activities that were previously more harmful to the climate. In many cases, it is simply a matter of increased internet consumption. The problem is that we as consumers are acting completely blindly, according to Professor Søren Hauberg from DTU Compute:

"When we use an AI service, we have no idea how many resources we are actually burning through. It is completely invisible. And because resource consumption is completely hidden, we mistakenly believe that using AI is cost-free. As consumers, we lack information that would make us more aware that we are actually having a significant impact on the climate and the environment when we use AI."

The internet is more than just data traffic

One way to get an idea of resource consumption is to perform life cycle analyses, which are calculations of environmental and climate footprints. Although ICT also encompasses activities other than our consumption of AI, it is a place to start in order to gain more knowledge.

This is precisely what Gudrun Gudmundsdottir is doing as a PhD student at DTU. Until 2027, she will be working on the research project ‘Absolute Environmental Sustainability Assessment of ICT technologies and services’.

In the project, which is a collaboration between DTU’s Centre for Absolute Sustainability and Professor Leif Katsuo Oxenløwe’s aforementioned research group, Gudrun Gudmundsdottir is working, among other things, on obtaining better data on ICT’s greenhouse gas emissions.

“A number of calculations have already been made on ICT emissions, but these mainly concern the energy consumption and CO2 emissions of data traffic. We lack knowledge about the emissions associated with the manufacture of all the devices and infrastructure we use to access the internet,” says Gudrun Gudmundsdottir.

She refers to devices such as phones, computers and television screens, and infrastructure such as fibre optic cables, antennas, data centres and networks that connect us to the internet.

The entire production of these technologies and hardware, and even the burial of fibre optic cables criss-crossing our countries and their deployment on the seabed, also has an environmental and climate footprint. And it doesn't end there, because later, when the equipment is obsolete and needs to be disposed of, this also generates emissions.

Consumers gain greater transparency

Gudrun Gudmundsdottir is working on developing a model that network operators, among others, can use to calculate their companies' climate impact.

"The model can ensure a uniform way for companies to calculate their environmental and climate footprint. It also gives them a tool to monitor their own efforts so they can keep track of developments. At the same time, it enables the rest of us to compare operators. We believe that this is the way to achieve greater transparency, so that both companies and consumers will one day be able to choose the internet providers or streaming services that are most climate- and environmentally friendly," says Gudrun Gudmundsdottir.

The question is whether companies are willing to share information about how much their services impact the environment and climate.

Professor Leif Katsuo Oxenløwe is optimistic. He has encountered nothing but a positive attitude from the companies he talks to, including the 18 companies that he is working with in the major research collaboration GreenCOM.

“All Danish internet and communication technology companies are really interested in the green transition, and they are very keen to become greener themselves. They just need someone to point them in the right direction,” says Leif Katsuo Oxenløwe.