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For some organizations, thinking about a new data center occurs in tandem with planning for what will happen to the old data center. What happens when a data center has reached the end of its life? It depends on what's going to happen with the building after the data center is decommissioned.
One option is to re-purpose the building for another use. Many data centers are part of a larger building that also includes office space. Depending on the age and condition of generators, chillers, and other MEP/fire protection systems, there is an after-market for used equipment. There is also a huge after-market to salvage electrical equipment and power cabling due to the high cost of copper.
If the data center has underground fuel tanks, they need to be removed and decommissioned in accordance with EPA requirements. Batteries in UPS systems need to be removed and recycled.
If you are moving out of your data center because you have outgrown the available power and space, one option is to re-sell the property to another user. There is a robust market in the United States for customers looking for existing data center space.
In some cases, the land may be more valuable for an alternate use, which would require decommissioning and demolition on the entire facility. Again, it's worthwhile to consider reselling heavy equipment and salvaging other valuable assets to maximize the value that can be obtained from the old data center.
It should be obvious that no one size fits all. Each type of data center is unique in its mission and life cycle. The up-front planning and total cost of ownership analysis of options are critical steps to a successful project.