Nine myths about prefabricated data centres debunked

Felipe Reséndiz busts common myths and misconceptions surrounding prefabricated data centres

There are many misconceptions in our industry when it comes to the pros and cons of prefabricated data centres.  The biggest single reason for this is that when people hear “prefabricated” they often immediately imagine a “containerised” solution.  These long, narrow and relatively inflexible ISO container-based units are only one form of prefabricated facility though.  Prefabricated data centres can come in many more flexible shapes and sizes and once built will often be indistinguishable from a traditionally constructed brick and mortar facility.

1) Design flexibility

Myth:  Prefabricated data centres have fixed designs with space restrictions that limit the number of racks, prevent the use of an elevated floor and restrict the types of cooling that can be employed because they use ISO containers retrofitted as data centres.

Reality:  Prefabricated data centres can be divided into two fundamental categories – those constructed with ISO containers and those that use larger modules.  Containerised facilities do indeed have many of the restrictions mentioned above.  However, module-based solutions are far more flexible and can be combined without internal walls to deliver infinitely configurable open white space.  This flexibility allows prefabricated module-based data centres to be designed with the same degree of freedom as a traditional brick and mortar facility, but with significantly lower overall project risk and far greater utility than their containerized cousins.  They can, therefore, be designed and built specifically for each individual customer’s precise needs.

2) Lifetime concerns

Myth:  Prefabricated solutions have limited lifespans as their steel construction will rust, just as containers do that are commonly seen on trucks, ships or trains.  So, they should only be used as temporary installations.

Reality:  Any building, regardless of what it is built of, will be affected over time by structural issues if it is not appropriately constructed right from the start.  It’s therefore critical to understand and prepare in advance for the environmental conditions that the data centre will be exposed to.  For example, a C3 coating on a steel structure will protect it against medium corrosion risk in industrial and coastal areas, while a C5 coating will provide protection at sea or locations with extremely high levels of humidity and salinity.  So, with appropriate protection in place, there is no reason why a prefabricated data centre cannot enjoy a lifetime of 40 years or more.

3) Thermal considerations

Myth:  When prefabricated steel-based data centres are exposed to the sun, they can heat up inside and require an increase in cooling capacity, thus increasing PUE and the operational costs of the HVAC units.

Reality:  Internal heat gain is a potential issue for all kinds of buildings and insulation is of course key.  Flexenclosure’s prefabricated modular eCentre data centres are equipped with insulated walls that deliver a very high thermal protection, with a U-Value of 0.6 W/m2K that minimises heat gains inside the installation.  The typical U-Value for a brick wall is 2.0 W/m²K and for a glass window it is around 2.8 W/m²K, so prefabricated data centres clearly be significantly more thermally efficient than a traditionally built facility.

5) Cost implications

Myth:  Prefabricated modular data centres are more expensive to build than brick and mortar facilities due to the shipping costs, import duties, installation challenges and specialised workforce required on site.

Reality:  In fact, the overall CAPEX investment required for a prefabricated data centre project can be 10 to 20 percent less than an equivalent brick and mortar construction.  This saving can be achieved because prefabrication in an offsite clean-room factory environment allows for a far more efficient use of people and materials than can typically be achieved at an onsite build.  Further, the higher quality control possible in an offsite manufacturing facility and the ability to fully test most installed systems before they leave the factory, significantly reduces overall project risk versus traditional construction methods and gives much greater control of overall project duration, which in turn positively impacts overall project cost.

6) Return on investment

Myth:  Prefabricated facilities do not deliver acceptable returns on investment.

Reality:  With the data services markets evolving at unprecedented speeds, data centre operators are having to evolve too.  Traditional new build projects taking two, three or more years to plan and execute are no longer acceptable and new data centre facilities now typically need to be up and running in less than 12 months.  They also need to deliver return on investment (ROI) in less than 18 months with an internal rate of return (IRR) of 30 percent or more.  Delivering on these targets with traditional construction projects is pretty much impossible, but not so with prefabricated facilities where increased project speed and control can deliver operational facilities extremely fast while meeting all financial targets.

7) Project duration

Myth:  Prefabricated data centres require a lot of installation and commissioning work to be done on site, delaying time to operations.

Reality:  On the contrary, prefabricated data centres have the advantage of having all their systems fully installed and tested prior to the modules leaving the factory.  This not only reduces the time required on site for final system commissioning, it also completely avoids the significant risks involved with transporting sensitive data centre equipment to a dusty and busy building site for local installation (as is required in traditional construction projects).  This pre-installation of systems in a prefabricated facility typically delivers a saving of up to four times the time required for equivalent onsite systems installation and commissioning of a data centre.

8) Scalability advantages

Myth:  There is no benefit to building a prefabricated data centre versus a traditionally built one when it comes to the facility’s future scalability.

Reality:  Ideally, new data centres will be built according to current capacity needs while allowing for expansion as and when the business grows.  However, expanding a live brick and mortar data centre will typically expose the facility to extreme operational risk, so traditionally built facilities tend to be specified and built according to projected future capacity requirements and this, of course, is completely inefficient.  Prefabricated data centres do not have this problem as the site works required – whether building a new data centre or expanding an existing one – are relatively limited.  Prefabricated facilities can therefore be scaled up in size as and when necessary with no risk to ongoing data centre operations, and in this way, resources can be efficiently utilised with CAPEX investment staged over time.

9) Facility certification

Myth:  Prefabricated data centres cannot get an independent design or construction certification because they are considered to be temporary installations that do not meet acceptable availability, redundancy or security requirements.

Reality:  Prefabricated modular data centres can be designed to meet any availability level required by the operator.  Further, prefabrication as a construction methodology has not only been fully accepted by all independent data centre bodies, it is acknowledged by many as the way most data centres will be built in the future.  Flexenclosure has pioneered the deployment of Uptime Institute tier certified prefabricated modular data centres in multiple countries around the world – with both design and construction accreditation – delivering total peace of mind to their operators.

A prefabricated future

It’s clear that prefabricated modular data centres can deliver everything that data centre operators are looking for today.  The latest prefabrication techniques are allowing data centres to be built in a far more cost-efficient way than ever before, for fully flexible and bespoke facilities of all sizes, whether hyperscale, core, edge or micro.

It’s a process that has been tried and tested.  And it works.  In fact, the main challenge faced by prefabricated data centres is not the construction methodology itself but its historical perception as a narrow and inflexible ISO containerised product.  Those times are over though.