The popularity of modular data centers is growing because the approach promises to help almost any enterprise, regardless of size or industry sector, add IT space in less time and at a lower cost than building or expanding a conventional operations center. And unlike a traditional data center, a modular facility can be located almost anywhere -- next to an office building, on a spare piece of land, on a company parking lot or inside a warehouse -- as long as there's access to energy, water and network resources. "The two big things that people consider are reducing the cost and cutting the time to deployment," Lee says.
Another advantage of modular data centers is that they allow users to start out small and expand as needed. "It starts to become more affordable for midsize companies that want more of a true data center room rather than just a small server room," Bailey says. "It's very different from having to build a traditional brick-and-mortar data center, where you're trying to figure out how much capacity you'll need for the next 20 years."
Modular offerings come in three basic styles. There's the original concept of a reconfigured shipping container (usually referred to as a "pod") that the vendor typically packs with IT gear and drops off at the customer's selected location.
Alternatively, some vendors have begun offering prefab structures that are designed to provide more flexibility in both interior space and layout configuration. "It gets either partially or completely built in a factory and shipped to your site; then the building is completed on site," Bailey explains.
The third approach is a hybrid model that combines both modular and traditional features. Here, vendors lease quickly configurable and expandable modular spaces, located inside large office buildings or plant-style facilities.
Many modular vendors, particularly pod makers, market their offerings as all-in-one packages that include servers and related infrastructure equipment, as well as power, cooling and other resources. "It can be a convenience or a trap, depending on how you look at it," Lee says, noting that customers may find themselves gaining speed and convenience in the short term but losing IT flexibility in the future.
Purdue's Compelling Case
Campbell began exploring his modular options for Purdue after it became apparent that the university's high-performance data center was in dire need of additional power. The facility's seemingly unquenchable thirst for electricity -- driven in part by three large server clusters built within the past three years -- was threatening to drain its co-tenants' power resources. "It's a 10-story building; we are in the basement of that building, and we consume 85% of the power," Campbell says.
An electrical upgrade was vital, but Campbell couldn't wait for the required bureaucratic approvals. "Getting an electrical upgrade... is a two-to-three-year process," he says. "We just didn't have time for the process to work its way through."
Campbell realized that he needed to do something fast or the university's research projects would soon begin suffering. He and his staff examined and rejected several potential options. "We looked at other places on campus that might have space and power available, but we couldn't find any," he explains. Colocation was also considered and eventually rejected due to logistical and cost concerns.
Running out of choices, Campbell and his team turned their attention to modular offerings and saw several benefits. Pod-based structures, which could be deployed quickly on land near the main data center, could reduce the pressure on existing resources and accommodate future growth.
Most important, the modular structures wouldn't have to undergo the same approval process as a new building. "They are considered a piece of equipment, rather than a building or construction expense," Campbell says. "So we could take this off the shelf and, in two or four months, have it up and going."