Ranked as one of the world’s leading modern higher education institutions, the University of Plymouth’s primary data centre is central to its IT estate. With the pre-existing cooling system nearing the end of its optimal service life and the School of Applied Mathematics requiring a capacity upgrade to accommodate its high-performance computing (HPC) hardware, the university employed the design and installation services of industry expert 2bm.
Assisted by Transtherm’s team of experts, 2bm overcame a number of site and budgetary restrictions to deliver a compressor-less cooling solution that surpassed performance expectations. The system achieved an 85% reduction in energy consumption and a PUE of 1.12 and below, even during one of the hottest UK summers on record.
Matthew Evans, technical manager for design and build at 2bm, explains his vision for the project: “The University of Plymouth’s existing data centre cooling system comprised process chillers, pumps and sequencing panels feeding internal in-row units. Despite the traditional internal cooling hardware, we were keen to push the boundaries of design and specification in order to deliver tangible results and a stable environment.”
Adiabatic technology
Rob Sewell, director for design and build at 2bm, adds: “It’s easy to habitually specify the same cooling systems project after project but working closely with skilled manufacturing partners to explore new possibilities allows us deliver energy efficiency and plant performance advances. It was this ethos that led us to use Transtherm’s adiabatic technology to retrofit a highly efficient compressor-less solution to a site using more conventional internal cooling hardware – something which many data centre architects would shy away from.
“For us, compressor-less data centre cooling is best practice and is a logistically viable solution for every data centre in Europe, even on tight budgets. We believe it should be the future for all data centre cooling solutions.”
Transtherm director Tim Bound continues: “Now that server technology can withstand marginally higher temperatures, there is a steep upward trend for bypassing refrigerant or compressor technology in favour of using ambient cooling systems to directly cool the data centre, rather than dissipating heat from the primary cooling plant.
“This not only delivers improved energy efficiency ratios but also offers shorter payback periods and quicker lead times. The project at the University of Plymouth showcases what can be achieved with this particular innovation, even with legacy data centre infrastructure.”
In fact, the use of variable speed fans for this project delivered an EER of more than 100 for 80% of the year; an impressive figure given the narrow cooling window between the air temperature and the required water temperature on site.
Like many data centre environments, it was imperative that the university site was kept live throughout the capacity upgrade and installation of a new cooling system. Space in the plant area was limited and the building required a number of important modifications to ensure health and safety compliance before the new HPC hardware could be installed.
Coastal protection
Sitting so close to the Plymouth coastline, componentry manufactured from corrosive-resistant materials were also a prerequisite of the project specification. In addition to these key project considerations, the base requirement for the cooling technology overhaul and capacity upgrade was an N+1 resilient solution, capable of delivering 100kW of cooling capacity to the existing data centre, as well as the new HPC cluster [with up to 20kW per rack possible].
The project required two 100kW, four fan adiabatic V-coolers capable of cooling water down to 24.5°C in the peak of summer and to 18°C throughout cooler parts of the year.
Constructed using aluminium-magnesium fins, stainless steel flanges and a painted galvanised steel finish, Transtherm’s coastal protection package of material upgrades proved ideal for the location of this project.
Bound comments: “It is often tempting for clients to cut corners when it comes to specifying the right grade of materials for coastal, or chemically harsh environments, but in order to deliver the longest service life possible in corrosive applications, these upgrades are vital.
“For this project in particular we went one step further,
using aluminium-magnesium alloy fins, which offer better heat transfer than the traditional epoxy-coated fins often used for semi-coastal locations. This option also eradicates the concerns associated with the fin cutting process exposing bare aluminium on coated components.”
