e gas-generated backup power kicks in. Increasing or decreasing the number of people in the data center will further impact cooling needs. In addition, there are different cooling requirements for equipment located at the bottom of racks VS. equipment located at the top. The type and amount of lighting also impacts cooling requirements. Energy consultants offer consulting services aimed at designing cost-effective energy and power systems for data centers. Taking Steps to Ensure Adequate, Lower-Cost Power To save money on electricity, some large enterprises have applied for and received permission from the United States Federal Energy Regulatory Commission (FERC) to become wholesale providers of electricity. By doing so, they can purchase bulk supplies of power at low rates. In addition to saving money on power purchases, this ensures that they have an adequate supply of electricity for their own power needs. Examples of companies that have been approved by FERC to purchase bulk supplies of electricity include Google, Exxon Mobile, Kimberly- Clark Corporation, Alcoa, Tropicana, and The Dow Chemical Company. None of these companies have stated an interest in reselling electricity on a retail basis. While it's not expected that smaller organizations will follow this route, this does point out the efforts that large, multisite firms will take to ensure an adequate supply of electricity at the lowest possible rates. To further ensure a steady supply of power, companies also purchase power from multiple power generating companies over different power feeds. In addition, electric rates and adequate sources of power often factor into decisions of where to locate data centers. For example, Facebook has two data centers located in Sweden, partly to cut down on cooling costs. www.TechnicalPDF.com Resiliency in Data Centers: Continuous Operation A key task in designing data centers is determining which devices or elements represent single points of failure that have the potential to put the entire data center out of service