A high performance computing data centre in the UK has reduced its carbon emissions by 75% after adopting a new approach to sourcing renewable electricity. The project offers an example of how energy intensive digital infrastructure can expand while easing pressure on the electricity system.

Stellium Datacenters, which operates one of the UK’s largest purpose built data centre campuses near Newcastle, has moved to an hourly matched renewable electricity supply. This method aligns its energy consumption with renewable generation on an hour by hour basis, rather than relying on annual accounting.

The change comes as data centres face increasing scrutiny over their environmental impact. The rapid growth of AI and cloud computing has raised concerns about electricity demand, grid capacity and rising energy costs. These concerns have reached policymakers, with MPs launching an Environmental Audit Committee inquiry into the sector’s use of power and water, as well as its impact on local infrastructure.

Stellium’s new energy model has been developed in partnership with renewable supplier Good Energy. The system connects the site’s electricity use directly to power generated by more than 3,300 independent renewable generators across the UK.

This approach enables the company to track when its demand is met by renewable sources. Stellium reports an hourly matching score of 95.4%, compared to a market average of around 43%. Planned additions, including large scale battery storage, are expected to increase this to between 97% and 98%.

The model also provides visibility over the specific renewable assets supplying electricity at any given time. This level of traceability is becoming more relevant for large technology firms with strict emissions reporting requirements.

Traditional renewable electricity procurement often relies on certificates that confirm clean power was generated somewhere on the grid over a year. This system does not guarantee that renewable energy was used at the same time electricity was consumed. As a result, fossil fuel generation can still be used during peak demand periods, even under “100% renewable” tariffs.

Hourly matching addresses this gap by aligning consumption with real time renewable generation. It provides a clearer representation of emissions and grid impact, particularly during periods of high demand when fossil fuels are more likely to be used.

Stellium states that the shift has changed its engagement with customers, regulators and auditors. The company can now demonstrate when and where renewable electricity is being used, offering detailed evidence to support emissions reporting.

Paul Mellon, Operations Director at Stellium, said: “Data centres often get bad press for their high, inflexible energy use. But this shows that AI and high-performance computing don’t have to come at the expense of the grid or the climate. By switching to hourly-matched renewable power, we’ve been able to cut emissions dramatically while giving customers the transparency they increasingly demand.”

Good Energy has positioned hourly matching as a way to improve transparency and reduce reliance on fossil fuels during peak periods. The supplier works with a network of independent UK renewable generators, enabling direct links between generation and consumption.

Nigel Pocklington, CEO of Good Energy, said: “By matching electricity use with renewable generation hour-by-hour, Stellium can show when clean power is actually being use. That kind of transparency cuts carbon emissions, reduces reliance on fossil fuels at peak times and proves that digital growth and a resilient energy system can go hand-in-hand.”

The development comes at a time when the UK is preparing for a significant increase in data centre capacity. Expansion is being driven by demand for AI processing, cloud services and data storage across multiple sectors.

This growth is placing new attention on how large energy users connect to the grid. Local communities and planners are increasingly focused on the infrastructure required to support new developments, including electricity supply and water resources.

In this context, Stellium’s approach points to an alternative to offset based or annualised renewable accounting. By sourcing electricity in line with real time renewable generation, the model aims to reduce strain on the grid while improving the accuracy of emissions reporting.

Battery storage is expected to play a role in further improving matching rates. By storing excess renewable generation and releasing it during periods of lower supply, storage systems can help balance demand and maintain alignment with clean energy sources.

The case also reflects wider changes in how corporate energy use is assessed. As reporting standards evolve, there is increasing focus on when electricity is consumed, not just how much is sourced from renewables over time.

For data centres, which operate continuously and require stable power, this presents both a challenge and an opportunity. Aligning demand with renewable supply requires coordination, but it can also support grid stability by reducing reliance on fossil fuel generation during peak periods.

Stellium’s experience suggests that operational changes, combined with new procurement models, can reduce emissions while supporting system resilience. As scrutiny of the sector continues, similar approaches may become more common among operators seeking to meet regulatory and customer expectations.

With demand for digital infrastructure continuing to rise, the way data centres source and report their energy use is likely to remain under close examination. The adoption of hourly matched renewable electricity provides one route for balancing growth with the constraints of the energy system.