Abstract
In a time when computing power is becoming exponentially more integral to everyday business, energy efficient environmental control for data processing has come to the forefront of conversation in the pursuit of energy saving. Whether it is due to regulatory pressure or improving the bottom line, the need is the same; reduce energy use. In a typical data processing center, 31% of the energy use comes from the HVAC equipment. It is becoming common practice to integrate isolated aisles with containment to achieve better energy performance from HVAC equipment. This paper addresses a practical means of measuring the efficiency of the distribution system which correlates directly to energy used by the computer room air handler (CRAH). This study focuses on an 800sf server room located at a Hewlett Packard facility. The goal is to identify whether or not the technique outlined in a white paper titled Data Center Air Management Metrics-Practical Approach, should be used as a tool to evaluate and make recommendation for energy efficient retrofits. To carry out this case study initial temperature data was collected with-in the room prior to any changes being made. Metrics were derived which characterize aspects of the distribution system's performance. The server room was retrofitted with temporary improvements then data was recollected and metrics re-derived. The resulting metrics indicate the retrofits made improvements in the system's performance by reducing the recirculation by 9%, but failed to indicate any measurable difference in energy savings. This method for evaluating the distribution system for the purpose of making improvements showed to have little value for this case. Visual inspection is a quicker means of identifying potential for improving system performance.