During Part I, we identified the program stage of the total cost of ownership (TCO), which included developing the team, program interviews, program contents, and report generation. With thiscolumn, the goal is to describe the site survey process as well as key components of power, fiber, and threat (PFT) in site selection. The survey results and PFT play a critical role in the final selection of any new data center.


Site surveys and power, fiber, and threat

Table 1. A list of some common risk factors when evaluating the potential of threat.

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As we create the need to cost-justify building a new data center, senior management is likely to ask “Why can’t we expand our existing data center?” Therefore, within every study it is always necessary to look at the existing conditions of the currently operating data center. When creating a TCO, it is important to identify risks associated with current operations infrastructure. Identifying risks begins with as-built document review and field surveys by the engineering team. The basic risk assessment includes the following components:

  • Narrative descriptions of the intent of design on a per-discipline basis (often appearing in the original basis of design documents created for the data center)
  • Electrical systems description and single point of failure analysis
  • Mechanical systems description and single point of failure analysis
  • Security systems definition and physical systems audit
  • Age of existing systems and life expectancy
  • Business impact analysis (BIA) identifying cost of downtime
  • Scope of work statement to upgrade the existing site to the new program recently identified (last month’s issue)
  • Construction estimates to remedy risks uncovered within the survey

It is often the case that the cost and risks to upgrading an operating data center outweigh those of building a new facility. This, coupled with the cost of downtime identified within the BIA, creates a business justification statement that drives the need for a new data center.


While there are many variables concerning site selection, the “go or no go” decisions are often driven by the access/cost of power, fiber, and potential of threat (PFT). If the sites being evaluated fail within any of these categories, it is unlikely to be viable for the new data center.

Typically, a company will identify multiple regions within the U.S. that it would consider for a new data center. The regions are primarily identified with the assistance of a real estate broker and are based upon economics, demographics, workforce, and taxes. This, combined with the PFT, creates a holistic view of suitability to build the new data center within a given area. Upon identifying potential regions, a real estate broker can look for land for new construction as well as existing buildings that would be appropriate to renovate into the new data center.

Power. While most utilities can bring the required power to just about any site, the issue becomes the new utility power’s installation cost and schedule. The cost is often identified by the requested capacity of the line and the distance for the utility company to install it from their desired substation. Therefore, every request for power is different, and the cost varies according to utility provider.

The other power factor affecting operating cost is the cost per kWh. This varies from provider to provider, depending on capacity and how the power is generated. With hydro-power (generated by dams and other natural sources), for example, the cost can be as low as 2 to 3/kWh  If the power is generated by a coal plant or a nuclear plant, it often ranges from 7 to12/kWh. This becomes a real financial issue when operating 1 megawatt (MW) data centers and above.

Over the last couple of years, the awareness for data centers to migrate to a renewable energy source has become increasingly more important. The need to reduce the carbon footprint is becoming a reality, and companies prefer to take advantage of the green benefits associated with renewable energy. Therefore, when doing the PFT, consideration should be given to renewable energy projects.

Fiber. Fiber is perhaps the most difficult of the three when it comes to finding reliable data concerning carriers and capacity. While some fiber carriers such as Zayo publish their routes, the majority of carriers do not publish infrastructure data. When evaluating fiber connectivity within the region, metropolitan fiber (local), long haul fiber (national), and fiber under construction must all be taken into account.

The cost of fiber will depend on the distance of the lines the carrier must install to reach the data center site. In some cases, a tenant within the data center will request service, and it would be up to the tenant and carrier to identify the cost. In other cases, a carrier might rent space within the data center for its equipment and bring in the fiber at its own expense.

Threat. Disaster prevention criteria over the last 20 years has not changed much within the industry. Terrorist threats have been added to the list, but otherwise the basic elements have remained consistent. Also, when evaluating risk, it’s important to indicate the probability and severity of the risks.

To date, we have discussed the first two steps of TCO which include programming and site survey/PFT. Within the next column, we will address planning which includes site adaptation, estimating, scheduling, and equipment selection.