Energieffektivitet i datahallar
The number of data centers and their capacity is increasing throughout the world. Theenergy used in these data centers and the emissions from the use are increasing at thesame rate. The total use of energy will double from 2008 to 2011 based on the trends indata centers use. Research in this area says that the emissions from data centers willhave surpassed the level of airline traffic in 2020. The index used today to compare howefficient a data center is, called PUE, is lacking some information. It is not able tocompare different kinds of cooling solutions and it does not take in account the largeamount of heat produced in a data center. This development and the limitations of theexisting index calls for an improved way of measuring energy efficiency in data centers.This thesis suggests a changed index, which can compare different cooling solutionssuch as district cooling compared to chillers. The suggested index also gives a betternumber to facilities that re-use the heat energy produced by the servers and the chillers.During this work the new index has been called NPUE, Net Power Usage Effectiveness.This name might be changed before an introduction to users and the market.The major changes from PUE to NPUE can be summed up as:?NPUE measures the net energy flow to and from the data center, where PUEmeasures the electric energy or power delivered to the data center.?NPUE measures the energy used over a period of 12 months.The net energy to and from the data center incorporates energy in other forms thanelectric energy, such as cooling in the form of district cooling to the data center and heatenergy delivered from the data center.NPUE is supplemented by a few more data about the facility. These are data ofemissions, in the form of CO2, NOxand SOx, from the energy used in the data center. Itincludes a comparison of the security of the infrastructure in the data center based onTier-levels. Finally a comparison of how efficient the data center is using the servers