BACKGROUND
The London based data centre operator engaged with Future-tech to design and plan the logistics and sequencing associated with the refurbishment and upgrade of its primary data centre solution. All power and cooling equipment from the transformers, generators and UPS through to the air handling units and BMS have to be refurbished or replaced whilst maintaining live services to existing clients.
Much of the data centre’s critical infrastructure has reached the end of its serviceable life. Together with this, cabinet power densities have increased significantly since the late 90’s and early 2000’s and the data centre’s capacity now needs to be 9MW+ if it is going to provide market acceptable power densities.
THE BRIEF
- Complete a full audit of data centre’s critical infrastructure assets.
- Develop a roadmap and sequencing strategy that allows the removal, replacement and/or refurbishment of critical infrastructure without impacting live services or overall delivered capacity.
- Produce an M&E data centre design that doubles the technical power density provided to client white space within the same overall plant space footprint.
- Provide detailed budget costs and spending projections for removals of plant and services, plant equipment supply and data centre installation.
CHALLENGES AND CONSTRAINTS
Maintaining 100% delivered capacity whilst removing, replacing and refurbishing critical infrastructure presents a number of sequencing, co-ordination and space related challenges.
Squeezing 9MW+ capacity in to a facility that’s plant spaces and services routes were only designed to accommodate 4.5MW capacity presented significant space related challenges.
Both the Operator and Future-tech data centre Design Engineers were keen to use “standard” manufacturers’ equipment to ensure capital and operational costs were kept as competitive as possible. This strategy also simplifies servicing and greatly reduces the risk of vendor “lock-in”. Due to the space constraints on site this philosophy did make the data centre design process more challenging.
Where possible performance specifications for equipment were produced that enabled at least three manufacturers to meet specification and therefore ensure a competitive tendering process could be followed. In some areas this staunchly vendor neutral approach did increase the difficulty of the data centre design process, in particular space planning.
THE FUTURE-TECH SOLUTION
On engagement Future-tech first reviewed the Operator’s business plan and marketing strategy. This provided information on the potential clients and the type of co-location offering the Operator wanted to bring to market. This information immediately provided a high level picture of what the data centre solution needed to deliver in terms of technical solution and capacity.
This information also gave Future-tech an understanding of the funding structure and how capital would be released. This was used to provide a high level understanding of programme, overall delivery and any financial constraints.
With this strategic understanding of the Operator’s commercial objectives, drivers and constraints a detailed audit of the site was completed. The audit gave Future-tech a detailed understanding of the data centre infrastructure, its age, condition and opportunity for reuse. It also highlighted areas of potential issue such as congested services routes, risers and plant equipment areas.
Because the site was designed using a 2N, and a broadly concurrently maintainable topography, the replacement of critical infrastructure was possible whilst maintaining 100% live contracted load by using correct sequencing. The site is operating at around 25% live load so A and B systems could be split in to A, B, C and D systems. Load could then be shared across A and B whilst C and D infrastructure was replaced and/or refurbished. Once complete the live load could be moved across to C and D systems whilst A and B infrastructure was upgraded.
Resilience would only be compromised during works such as the transformer and generator upgrades when redundancy on those elements would be reduced to N. Ensuring 2N was maintained on the generators whilst the transformers were upgraded and vice versa was essential to minimise risk of downtime.
Due to the size of the data centre halls, incorporating the additional air handling units required to meet the new higher power density was relatively straightforward. The difficulty arose externally where space for heat rejection plant was significantly constrained.
To overcome this, an innovative framework data centre design was proposed by Future-tech which significantly increased the surface area of the plant space without increasing the overall footprint. Functional space was further increase by stacking heat rejection equipment such that free cooling coils are located beneath mechanically cooled coils. The mechanical coils are sized to ensure correct operation at the maximum free cooling coil air off temperature. This effectively doubled the external space available for heat rejection plant and resulted in the creation of a very energy and space efficient data centre solution.
The legacy cooling infrastructure uses direct expansion for heat rejection. This made the replacement of units relatively simple as units could be replaced and brought on line one at a time.
The new BMS and security systems design will be installed and tested whilst the site continues to operate using the legacy infrastructure. Once complete the new system will be brought on line and the legacy systems decommissioned.
Despite the complexity and potential risks associated with the refurbishment of this data centre Future-tech’s measured and methodical approach coupled with its knowledge of vendor solutions and working in live data centres resulted in a practical and pragmatic design and delivery programme.