The data center industry has experienced numerous changes and advancements over the past few years. From new critical infrastructure to innovative liquid cooling solutions, data center designs and constructions have shown a greater focus on efficiency, effectiveness, and environmental responsibility.
One of the most progressive and positive developments in data center design and building is in locating these important sites underground. While this approach may appear daunting at first, even raising some questions as to why one would take this tactic, upon further assessment it makes great sense for a company’s specific workloads and their use cases. Plus, in some geographies, placing all critical infrastructure and data safely underground is a sound approach for environmental and cost purposes.
There are two main benefits to locating a data center underground, each with increasing importance to end customers: security and cooling efficiency.
Naturally, having an underground data center provides extra security in a number of ways. Firstly, it provides an additional barrier to protect against potential intruders and those who wish to physically damage the data center and its critical infrastructure… and in turn the data center provider’s external or internal customers. Underground means not having an exposed perimeter wall to the sensitive white floor space where an end user’s IT would otherwise be more vulnerable.
Secondly, security extends to the roof of the structure which now has a much higher probability of withstanding physical attacks in the forms of rockets or other large artillery. While this may not be as important to customers in fully stable countries, it is a notable benefit for those that are in more sensitive political and defense zones.
For example, in Israel there are numerous data centers that are built underground by a series of providers. As one may understand, such locations provide greater protection from external missile attacks and terror-related activities for the hosted customers’ IT needs. In fact, whether it is UTI certifications or government-standard ballistic ratings, external parties recognize and assure that such prioritize security statuses are met by the leading data center operators.
In addition to security benefits, underground data centers provide ongoing operational expenditure savings for many companies by providing greater natural cooling. As anyone who has even been in a underground cavern can tell you, temperatures typically are many degrees cooler than on the surface. For a data center, these degrees can make a big difference in keeping servers cool which in turn assists the data center provider to keep the overall facility cooler by such natural rather than a higher amount of artificial means, such as CRAH-provided air cooling.
Power remains an extremely significant portion of any data center’s running costs, and that cost generally is passed on directly to an end customer if it is a hosting or colocation site. By reducing the amount of power needed for cooling given a greater natural source, the end customer receives an earthly discount in its own opex associated with renting space.
Of course, such power savings translate into environmental benefits, too. Less power consumption equals more sustainability and, when liquid cooling measures are utilized, less water is consumed. Let’s be honest: by definition older, above ground data centers will never really be environmentally friendly per se – at best they can be minimally impacting in certain conditions and layouts. And carbon neutral/zero footprint is only possible in newer data centers in very specific geographies such as upper Scandinavia.
With an underground data center providing a more sustainable and efficient solution to power consumption, the data center operator is more capable of achieving its own goals as well as those of those customers who have such criteria in their site selection policies and interests.
Going back to Israel for an example on energy efficiency, it has been calculated that underground data centers consume less power than their above ground counterparts. While local conditions and thus resulting savings may vary in other countries, let’s not think that Israel is so incredibly different than many other geographies. Its data centers primarily are located along its Mediterranean-climate coastal plain, or in the temperate hinterland that is adjacent to but not within the semi-arid region of the country. Yes, Israel is hot. But in those temperate locations the night air and seasonal conditions actually provide free cooling for much of the year. Even with such settings, the underground data center locations are expected to achieve a great proportion of the full economic savings that would occur in more year-round hot climates. Of course, the seeming costs of building an underground data centers are something that many people logically are interested in. So how much more expensive is it really to dig and rig below? Many key expense items actually remain the same no matter if one is going above or below ground including concrete, equipment, electrical and network connections themselves. The main cost differences appear in two main line items: excavation and internal works. Excavation costs for building an underground data center do run approximately 20% more than above ground. However, these costs frequently are recouped once the site is up and running via the lower power costs in the operational expenses ledger. Therefore, the true total cost of ownership can be lower despite what appears to be a more expensive way to build and run a data center. Internal works to build and prepare the underground data center are notably different than an above ground one. Yes, it can cost a touch more money to access the locations during construction and there may be more connection works to be done given that energy centers may be underground, too. But these additional costs are relatively modest compared to the ongoing savings and, in particular, the lower power consumption expenses.Importantly, having a lower power utilization up front lowers the risk of regulatory-driven energy reduction initiatives that create a potential need for data center layout changes, which would be rather expensive to implement. One can expect that political and environmental influences will continue to turn their foci to the data center industry. The better the energy consumption reality, the lower the risk of the data center having to be reset to align with new standards or statutes that would drive costs way up as well as creating negative publicity.As we can see from the above, having an underground data center has security, economic, environmental, and even political benefits. We expect that such designs and constructions will continue to be increasingly attractive, particularly in certain geographies where defense and warming risks may be greater. For those companies looking to build new data centers, or to collocate in one, the attractions of locating in an underground data center should be of strong interest.