Construction of Modular Datacentres
What are the key architectural issues to consider for modular datacentre?
As the needs for computer data storage are constantly increasing, the concept of modular datacentres is attracting more and more interest. What are the key architectural challenges and distinctive features of modular datacentres that must be taken into account? How do you to treat the specific issue of cooling?
External perspective of a modular datacentre project in Reims
Issues to consider in datacentres
Datacentres are very large computer server rooms and, as such, must meet the same challenges as all server rooms, notably the cooling of the space, the power supply and also security. However, the problems that arise on each of these specific issues are more complex in a datacentre. Their service and efficiency are continually evaluated and communicated in such a way to make sure their performance is always of the highest level. Their redundancy level, which ensures backup of the system in the event of component failure, is noted by a third party (e.g. the Uptime Institute). The energy efficiency is measured by its PUE (Power Usage Efficiency). The use of these indicators is important to assess the level of the services provided by the datacentre.
Building a modular datacentre
In choosing to build a modular datacentre, the investors are opting for a datacentre that can be built in several phases. Each increase in data storage space corresponds to an additional increase to the power supply, the cooling system and demand on the technical areas. In order to optimise the construction costs of building a modular datacentre, the architect must design a comprehensive project anticipating the integration over time of more modules. One of the architect’s tasks is to determine the ideal size of a modular datacentre: the minimum and the maximum size. The minimum size is defined by the smallest, most cost effective module unit, which can be repeated until it reaches the maximum size. The maximum size is the size above which it would be more efficient and cost effective to build a larger datacentre based on the specific architectural requirements of the project. Experience shows that the ideal size for a modular datacentre is between 1000m² and 4000m².
Solutions for the cooling systems in server rooms
Within a datacentre, whether modular or not, the server processors generate a significant amount of heat. The objective is therefore to remove this heat and cool down the equipment by developing suitable cooling systems. At the very least, this can be simply installing a ventilator that evacuates the hot air produced by the processors. However in most cases an air-conditioning system is required to cool the server rooms. The flow of cold air is directed more accurately within the server room, often by installing an air-conditioning system in the false ceilings or raised floors and placing the evacuation/extractor unit above or below the server racks. The cool air is then circulated through floor slabs or a perforated ceiling.
Systems of specifically targeted cooling
Some companies choose to focus the cooling into specific areas. Recently, a company decided to replace all its open refrigerated bays with closed glazed door units. This solution is particularly interesting as it allows for the cooling to be focused on when and where it is required: a real gain in terms of energy efficiency.
There are also solutions which allow the air to be cooled closer to the processors by passing the coolant through a system installed around the processor. However the disadvantage of this solution is that it requires specific types of servers and that there is always the possible risk of a leak into the circuit.
Reid Brewin Architects is one of the leading architectural practices in France recognised for its experience in the design and construction of data centres, including modular data centres. The firm has worked on many projects throughout Europe and the Middle East, notably in France for Global Switch, Equinix, Digital Realty, Telecity, Sodearif and Bouygues Energy Services.