Climate Briefing
AI DATA CENTRES - THE FACTS
HEADLINES
A1. Energy usage
Data centres are among the most energy-intensive buildings in the UK, consuming more than 3% of the nation’s electricity, equivalent to the amount of energy needed to power Birmingham, and with most of the consumption occurring in the South East and London. Currently, about half of data centre electricity demand in the UK is supplied by fossil fuels and half by low-carbon and renewable sources. However, in Norway, data centres use 100% renewable energy. Global electricity consumption from AI-focused data centres grew by 50% in 2025 and, in the UK, high levels of development in AI and off-site computation are expected to lead to a fourfold growth in data centre electricity demand by 2030. According to a University of Oxford study, a 1-megawatt datacentre, generally considered small to medium, uses enough electricity to power 1,000 houses and can use 25.5 million litres of water annually.
In addition to concerns about high energy demand, energy usage by data centres could also pose a challenge for the national grid. For example, the power usage for a data centre planned for Leeds is expected to be equivalent to 606,728 households per year (averaged over lifetime), doubling the strain on the local grid.
A2. Water usage
Data centres currently use approximately 6.6 million litres of water/day, equivalent to the water used by 20,000 average homes. With the government’s ambition to treble data centre capacity by 2030, this could increase to an average of 19.8 million litres/day, equivalent to 60,000 homes. However, peak demand during a hot summer could increase to 77 million litres/day, equivalent to the average daily usage of more than 235,000 homes. Water companies have received requests for up to 21 million litres of water per day from individual data centre developers, this difference in current observed peak demand and future requested peak demand is likely to be due to the sector planning for higher average and peak summer temperatures. For example, in an extreme dry year, the developer for a data centre planned in North Devon estimates that annual water consumption could reach approximately 2.9 billion litres.
The water companies are expressing disquiet about the water demand of data centres. Anglian Water has objected to plans for a data centre site in North Lincolnshire. Also, 28 new data centres would be serviced by Thames Water who have been talking to the government about water demand.
In some countries, e.g. Norway, hot water from data centres is used to run district heating systems. While The Netherlands are working on floating data centres alongside the canal network where cool water is effectively free.
A3. Land usage
Some data centres occupy large areas of land, sometimes on green belt or high-value agricultural land. For example, a data centre planned for North Lincolnshire will cover up to 435 acres, while a data centre is planned for North Devon which will occupy 850 acres of farm land. A proposed development on farm land in Auchtertool, Fife, will dwarf the village and its 200 or so houses and cover an area larger than 100 football pitches and equivalent to 13 stories high.
A4. Other effects
Data centres cause an increase in temperature, plus light, air, and noise pollution. Emerging research suggests data centres increase temperatures in their immediate vicinity by an average of 2℃, and as much as 9℃.
According to Dark Sky International, one data centre campus can produce more skyglow than an entire small town - and it operates at full intensity every night of the year. This has negative implications for nocturnal animals, such as moths and bats.
Emissions from fossil fuel-powered data centres have implications not only for climate change, but also more immediately for air quality. It’s estimated that data centres with on-site fossil fuel generation at scale result in £42 million to £79 million annual public health costs due to increased exposure to harmful pollutants.
Data centres generate continuous noise due to cooling fans, transformers, and ventilation systems, and intermittent noise caused by backup generator tests, unscheduled use of generators, and site traffic. Continuous noise from cooling fans and transformers reaches 60 to 80 dB at the property line, comparable to a busy street. Generator load tests and low frequency hum can be heard up to a mile away. The defining problem is the continuous nature of the noise, not the peak loudness.
A5. Job creation
According to a study by Verdant, existing UK data centres support roughly 4,400 direct jobs, not the 24,300 claimed by industry. Planned developments are expected to create around 10,400 total direct jobs nationally - about a quarter of the industry's projected 40,200. Data centres create dramatically fewer jobs per unit of electricity demand than steelworks, car plants, hospitals, or schools. For example, a hyperscale data centre in Blyth, north-east England, is expected to support only 400 full time on-site jobs, while developers for the Auchtertool site say it will create 120 jobs. This is in contrast with the 8 million UK jobs which are at risk due to AI.
BACKGROUND
B1. Purpose
Data centres house computers supporting the growing use of the internet and AI. Computers in data centres have a variety of purposes, from storing photos and emails, facilitating video calls and streaming, to training and operating generative AI models like ChatGPT and other chatbots. The data centre requirements of chatbots and generative AI video creation tools vastly outweigh those of non-AI digital activity.
B2. Critical national infrastructure
In 2024, the government designated data centres as critical national infrastructure, putting them on an equal footing with water, energy, and emergency services systems, but with higher priority than houses and hospitals. Further, the government is planning to designate data centres as an essential service, meaning that data centres above certain defined thresholds will be required to have appropriate measures in place to manage risks, with Ofcom serving as a regulator.
More recently, the government has proposed a ‘covenant’, whereby data centre developers promise good behaviour in return for getting priority in connecting to electricity supplies. The aspirations for good behaviour in water use are weak on the question of how they will be achieved or enforced. The Government has given their plans the status of a National Policy Statement - currently only a draft for consultation but when finalised it will count for a lot in terms of planning law.
B3. Expansion
The largest technology companies are contributing to a surge in data centre investment, as their capital expenditure exceeded USD 400 billion in 2025 –and is expected to jump by another 75% in 2026. Capital expenditure of just five technology companies is now larger than global investment in oil and natural gas production. This is having an impact on the cost and availability of finance which has implications for UK Government borrowing costs.
B4. Water
The largest volumes of water used by data centres are for cooling computer chips used for processing information. In open loop cooling, water is passed through a data centre to cool chips and heated water is then evaporated. This method tends to be the least water efficient. In closed loop cooling, water is either used to wet a media through which air passes before it cools chips or liquid cools chips directly with heat subsequently ejected through a secondary cooling system. These systems tend to be much more water efficient.
NOTE TO MPs
We at MP Watch have represented the facts after consultation with scientists. We ask you to consider whether there are any facts that we have presented that you disagree with, any key facts you think we have missed out, or any conclusions or interpretations that you disagree with.
If there are would you let us know which ones and why you disagree or what you think we have missed.
Our intention is to have a constructive two way conversation with you and other MPs so that we can develop a common understanding of the situation based on an acceptance of mutually agreed facts.
We hope that such an understanding might reduce the amount of disinformation and misinformation that is so often present in debates on the floor of the HoC - and also in the media and general public discourse.