Billy Durie, Global Sector Head for Data Centres at Aggreko, explains why adopting battery energy storage systems (BESS) as part of a wider, end-to-end solution is key to keeping data centre builds on track.
The rapidly growing demand for more data centres around the world is quickly exceeding levels of supply. Savills predicts that in Europe alone, data centre power capacity will total 9,000 MW by 2025 and the number of data centres will need to increase by almost 2.5 times. This equates to more than 3,000 data centres being built in the next year to meet demand.
Spurred on by many factors, including the transition to working from home post-pandemic and the rise of AI, access to data is rapidly becoming an integral part of everyday life. In Southern Europe alone, the number of internet users is expected to grow to 208 million by 2027 from roughly 195 million in 2023.
Attempting to meet this extra demand is putting great tension on data centre construction. While there are multiple factors that may delay data centre builds, project managers are too familiar with some of the most common pinch points. Wait time for a grid connection is the main concern, with emissions standards and clean air zones a secondary factor which further complicates the issue.
Two common hurdles data centre construction must overcome are local emissions standards and waiting time for a grid connection. These can both be managed by implementing battery energy storage systems (BESS) onto site which work alongside generators to ensure data centre builds always achieve a steady power supply, specifically during periods of peak demand.
The great grid queue
Anyone operating in the data centre construction industry will know the huge amount of power required during an average build. A growing need for more data centres across Europe means this demand will only increase. Now, multiple builds are stagnant, in seemingly endless queues waiting for a connection, like the more than £200 billion worth of renewable projects sitting in line to connect to the UK’s National Grid. This waiting game is especially arduous in the FLAP-D markets (Frankfurt, London, Amsterdam, Paris and Dublin), with some placing moratoriums on new builds or only considering applications on a case-by-case basis. A reliable connection is difficult to find which causes delays to project schedules, even in cases where data centre builds are successfully and promptly connected to the grid.
BESS, as part of a hybrid power package, can be incorporated to reduce reliance on the grid once the load profile of a site has been identified. Rather than waiting for a grid connection, these hybrid solutions give power control back to site managers who can use the setup to avoid connection bottlenecks and keep construction running smoothly.
Environmental considerations
Numerous data centre construction sites must adhere to local environmental and noise regulations which influence the selection of appropriate equipment and operating hours. A combination of a Stage-V generator and a BESS system, known as a hybrid system, can be beneficial in these situations. By utilising a hybrid system, it is possible to provide zero-emissions power during periods of low demand, such as at night, when the battery is the sole power source. These generators can also operate on hydrotreated vegetable oil (HVO) or be combined with renewable energy sources to further reduce emissions. For instance, utilising stored energy in BESS as a backup power source during intermittent power supply can assist sites with unreliable connections or fluctuating power needs.
This is of increasing benefit for colocation DCs in urban areas where noise or clean air zone restrictions often impact a build. Widely regarded as the top DC market in Europe, London data centre construction has had to grapple with a widening Clean Air Zone (CAZ), highlighting the merit of hybrid solutions that can follow current and future environmental legislation.
Understandably, many businesses, especially those involved in data centre construction, are worried about the initial cost required to integrate renewable energy sources. But many greener solutions, such as BESS, provide a low-risk, high-reward option to achieving more sustainable construction.
To illustrate, when powering temporary office cabins during the build phase, a hybrid solution comprising 3 x 320 kVA generators and a 300 kW battery can provide significant reductions in fuel usage, costs and emissions. In this scenario, an estimated 20,000 litres of fuel and 53,000 kg of CO2 emissions can be saved over a two-month period.
Rebalancing power control
In addition to complying with environmental regulations, BESS can be integrated with Stage V generators to help site managers effectively manage power loads and ensure that emission levels remain within safe limits. Remote monitoring capabilities also enable site managers to analyse and optimise their load requirements for maximum carbon savings.
Again, construction on many collocation projects can benefit from downtime without concerns about power supply interruptions, thanks to BESS. This feature also enables data centres in urban environments to adhere to emission limits and remain competitive, overcoming potential hurdles that may have previously caused delays in project completion.
Making faraway connections
Data centres constructed in urban environments are not the only projects that can benefit from incorporating BESS on-site. Projects a long way from the grid in remote areas can also realise the environmental benefits of these bridging solutions to enable construction in energy insecure locations.
In some cases, data centres are deliberately built in some of the most remote locations in the world, like the Nordics, due to the free cooling potential. But this also presents grid issues, as the power framework required to build a project of such scale is not always available in such remote areas. Also, a portion of these hyperscale builds can have thousands of construction workers on site, a costly factor in the case of outages without a backup power source. This backup solutions can be provided in the form of BESS for those builds finding it difficult to achieve a stable grid connection while keeping projects in line with tight environmental legislations.
BESS capacity is increasing across Europe, with the UK adding more large-scale capacity in 2022 than any other nation, and projected to quintuple its energy storage capacity by 2030. These large-scale investments solidify the case for BESS construction in countries with or without stable connection to a grid. If construction is to keep up with astronomical demand for data in some of the world’s most urban and remote locations, bridging solutions will inevitably be part of the wider solution conversation.
