Why early acoustic input matters for UK data centres

The UK government will release its Autumn budget at the end of November. Given the government's previous statements on priorities, data centres being designated as a national infrastructure, and AI continuing to be each nation's key economic growth strategy, we can expect increased funding in this sector alongside the recently changed planning reforms. London is Europe's largest data centre market, hosting over 514 data centres. It is predicted that data centre power consumption in the UK will increase sixfold within the next ten years. 

Achieving these aims will require significantly expanding existing facilities and new gigawatt data centre campuses nationwide. However, with this comes an increasing potential for noise pollution. Data centres house servers, which generate heat as they operate. To prevent overheating and maintain efficiency, cooling systems such as fans, chillers, and backup power generators must be utilised. However, these can produce large amounts of noise from the fans and motors. 

As more data centres are being built in already noisy urban areas, noise-induced health impacts on the local community are likely to increase. Because of this, careful planning and effective noise-management strategies must be integrated into the full design to reduce these impacts.  

Setting appropriate design noise limits

Setting appropriate noise limits depends on the location of the data centre. In the UK, assessment methodologies are based on an extensive baseline noise survey. This determines the noise levels at receptor locations and is affected by factors like nearby roads, railways, aircrafts, or industrial noise, and noise limits are then set relative to pre-existing conditions. However, other regions may use fixed limits which refer to pre-defined decibel levels and cannot be exceeded regardless the context.

Early site selection tools do not consider this, which means that a data centre design could comply with noise limits in one neighbourhood, but it is not guaranteed to comply with those in others.  

Optimising site layouts

To minimise the impact of noise on neighbouring properties and reduce the need for costly noise control measures later on, the site layout needs to be carefully considered. The main strategy is to utilise buildings for acoustic screening and strategically place plant zones, as these are key locations for noisy equipment.  

For example, we recently assessed the feasibility of a 40MW data centre, reviewing different system approaches and plant configurations in close collaboration between the mechanical, electrical, and client teams. The proposed solutions addressed potential site concerns raised by the local planning authority regarding noise impacts on adjoining properties, while providing efficient solutions that deliver the required levels of resilience.  

Assessing noise holistically

In our experience, assessing the cumulative noise impact of all sound sources within a campus requires a holistic approach. For example, while a single data centre may be designed to marginally comply with noise-limiting criteria, any expansion of a campus must be significantly quieter to avoid exceeding the limits. However, this can invariably mean that envisaged capacity increases cannot be realised.  

We recently led a multi-disciplinary engineering design programme for a data centre campus in central London. We assessed various site configurations using acoustic modelling and computational fluid dynamics to optimise the design for noise limits and balance acoustic performance with heat rejection. The findings led to the development of a canopy lid and reduced fan speed to prevent waste heat from recirculating back into the data centre once it had been expelled. This approach reduced cooling energy requirements and ensured compliance with noise regulations, supporting sustainable operations and reducing the ecological footprint while maintaining optimal acoustic performance.  

Starting early sounds good

Involving acoustic consultants early in a project is imperative. To support the UK's ambition to become an AI superpower, more data centres will need to be built, making meeting planning requirements vital. Acoustic engineers can bring their expertise to the full design to optimise site layouts and reduce the environmental and social impact of the noise. By working collaboratively with a multi-disciplinary team, the viability of a project can be understood without compromising on mission-critical infrastructure.