The concept of using underground bunkers for protection is far from new. Underground facilities have been used as bomb shelters, as fallout shelters and even to store fissionable material. Why not apply the same underground protection to data centers? Building a data center below ground offers a number of advantages, from the obvious savings in cooling costs to protection from natural disasters and outside elements.
Although underground data centers and data shelters are somewhat rare, they do exist. Many are owned by private colocation companies, although there are other examples scattered around the country and operated by companies that want to offer better data security and protection.
Three Underground Examples
1. The largest underground data center in the U.S. is in Butler County, Penn., and is owned by Iron Mountain. The data shelter is 220 feet below ground in a limestone cave that was formerly a mine. The facility is highly secure, with 24-hour security, closed-circuit television, X-ray scanners and magnetometers. The data bunker can handle 7 million gigabytes of data and is primarily used for secure data backup, such as emails, corporate files and electronic medical records. The shelter also has redundant and failover systems as backup for aboveground facilities. And Iron Mountain’s facility has access to an underground lake in order to facilitate cooling, so the facility maintains a constant temperature of 52 degrees.
2. Cavern Technologies maintains a facility under 125 feet of limestone in a former mine near Kansas City. The facility has more than 300,000 square feet of operating space and handles data for healthcare facilities, insurance companies and universities. It’s secured by guards, biometric scanners and smart cards. The data center is air-cooled with centralized climate controls underground.
3. InfoBunker has converted a former military communications base located underground outside Des Moines. The 65,000-square-foot facility is located 50 feet underground and hosts data for telecom companies, insurance companies, hospitals, financial services, e-commerce and others, as well as two backup data centers.
Considerations for Going Underground?
Most underground data centers take advantage of existing underground facilities, which saves the cost of excavation. No matter what type of underground facility you choose to host operations in, there are a number of considerations before going underground:
Choosing the right location – Not all underground locations can be adapted as a data center. Older mines from the 1960s or earlier, for example, may not be suitable. Newer excavations have more space. In limestone facilities, you also have to be sure the limestone itself is preserved at the proper thickness, and the space has to be big enough to handle equipment with 25-foot to 30-foot stone columns. Maintaining structural integrity underground can get in the way of neatly placing cable and equipment.
Cooling – The most obvious advantage is cooling. Chiller operations are the biggest expense for most data centers. Maintaining a consistent humidity and operating temperature requires high-powered air-conditioning systems that use a lot of energy. And when the weather changes or there is a heat wave, the costs increase. With an underground facility, you have natural cooling built in, and caves are not subject to external weather conditions. Of course, once you load a lot of heat-generating computer equipment in an enclosed underground space, proper ventilation is required for the equipment and the comfort of the staff.
Less construction time and cost – One of the advantages of building an underground facility is the shorter time to market. Even a large data center can be deployed quickly if there is sufficient room underground. Construction costs are substantially lower because tehre is no need for a concrete shell, and in areas such as the Midwest or the Atlantic coast, there is no need to disaster-proof the site or ensure it can sustain tornados or hurricane winds, which can cost an additional $100 per square foot.
Connectivity – One of the biggest costs of going underground is laying fiber to the location. Most underground data centers are in remote locations, so you may have to lay a substantial amount of cable for Internet access.
Exterior equipment – You may not be able to install all the hardware underground. Generators, redundant power systems and other mechanical and electrical equipment may need to be installed outside or against an exterior wall. These systems will need adequate protection in order to make sure they don’t become a point of failure because they are more exposed. You also have to be concerned about other issues such as fire safety—what effect would water have on mechanical and electrical systems if sprinklers are activated?
Staff considerations – There won’t be any natural light underground, which is really not different from aboveground data centers. However, you might consider using full-spectrum light bulbs and other tactics in order to make working underground more comfortable. A bigger issue could be facility access. Most mines and underground locations can be difficult to access, and there may be parking limitations.
In addition to the cooling benefits, going underground also cuts out the threat of radio interference, microwaves and even electromagnetic pulse weapons. Physical security becomes less of a concern, because there is typically only one entry point, so it’s easier to control access. An underground data center may not be everyone’s idea of a perfect data facility, but there are a number of advantages, and you don’t have to dig very deep to find them.