Data Centers are hungry for energy. As of 2006, the electricity usage attributable to servers and data centers in the United States was estimated at about 61 billion kilowatt-hours (kWh) according to a ‘Report to Congress on Server and Data Center Energy Efficiency’. It is similar to the amount of electricity used by the entire U.S. transportation manufacturing industry (which includes the manufacture of automobiles, aircraft, trucks, and ships). The total energy draw of data centers have grown. Using these amount of energy leaves a huge carbon footprint. According to KPMG, the total global ICT industry is responsible for approximately two percent of worldwide carbon emissions, equivalent to the emissions from the airline industry. These developments are pushing the boundaries of current power and cooling infrastructure designs and forcing a rethink on fundamental energy issues. There is an increasing attention in calculating the energy usage of a data center. But calculating a PUE gives only a number. For a better understanding a more thorough analysis should be made to improve energy efficiency. This also means that we should be aware about the question: What do we mean exactly with efficiency and optimal?
Lets look at the following point of view:
- Energy efficiency; emphasize on becoming increasingly efficient in the usage of energy whilst economic growth can cause continuing use of more energy.
- Energy productivity; emphasize on sustainable development because of the scarcity of energy resources and the interest and concern of the climate change and the carbon dioxide emissions.
It looks like that Green IT is more about sustainability and thus energy productivity then energy efficiency. Although Green IT and energy efficiency are more commonly used and excepted as goal, that is how to reduce energy use without loss of economic performance. Considering the Climate change issue the goal of economic performance instead of economic sustainability looks rather short-sighted.
This approach of measuring and analyzing energy consumption incorporated with life cycle energy analysis, also known as Energy Accounting, can improve energy and environmental decision-making for the data center. Analyzing the data center energy usage is also talking about Energetics, the study of energy flows and storages under transformation. Howard Thomas Odum was an American ecologist who put a lot of effort in the development of energetics and developed an Energy Systems Language for the thermodynamics of open systems. This combination of ecology and thermodynamics is a very interesting perspective for the data center energy analysis.
For the subject of energetics much can be found at Emergystems.org