The Green IT SI (Swiss Informatics Society) developed an assessment and a catalogue of measures for data centers as well as a general catalogue for the implementation of in-house Green IT measures (Green in IT). The most important recommendations and procedural steps are listed below.
The assessment and the catalogues of measures are currently being used in the “Less electricity, more efficiency in server rooms and computer centres” campaign, which is made possible by the Swiss Telecommunications Association (asut) with the support of SwissEnergy and numerous partners from the private sector.
The Assessment and the catalogues of measures are available in German, French and English.
Knowledge and tips for an energy-efficient data center
- Company data centers can consume half of all energy in the ICT sector, depending on the situation. Large data centers are generally more energy-efficient than medium-sized or small data centers if cooling and waste heat reuse are optimally planned. The operation of a proprietary data centre must therefore be well considered.
- Data center technologies have developed strongly in recent years. Heat dissipation from increasingly compact chips and power consumption are the decisive challenges. Examples of recent advances include immersion cooling and self-powered data centers. The choice of location remains a key aspect of data center planning.
- The design and operation of energy-efficient data centers should follow best practices that can be shared by area experts. Most computer center hardware and infrastructure manufacturers also offer helpful documentation and services.
Survey of hardware manufacturers
Many data center operators fail to address the issue of increasing system room temperatures due to their unwillingness to modify the existing infrastructure couples with their wish to abide by the recommended temperature of 23°C or less reported in the various data sheets of server, storage or network manufacturers.
We have written to the major IT vendors (Dell, Fujitsu, IBM, HDS, EMC, HP, Oracle(SUN), Cisco) and asked them explicitly whether they support an increase in the temperature in the data center in accordance with the ASHRAE standards 2008 and 2011.
The questions
- Can all your equipment tolerate an inlet temperature of 27°C indefinitely?
- Are there exceptions?
- Does your device need more power when the inlet temperature on the device is raised to 27°C?
- How much does the power consumption increase when the inlet temperature in front of the server is raised from 24°C to 27°C?
Questions 3. and 4. serve to determine whether the energy savings from the reduced cooling in the server room are offset by the server fans, which run faster at higher inlet temperatures.
The answers
- The devices of the interviewed manufacturers can operate without restriction with a 27°C inlet temperature. The upper temperature limit is now 35°C and for some 32°C.
- No exceptions were mentioned.
- It was confirmed that certain fans already run faster at 27°C inlet temperature and therefore consume more power. This behavior is increasingly noticed with new servers, which have a highly temperature-optimized fan control.
- Curves show how the power consumption increases, but without a qualitative statement about how much the total power consumption in the server increases.
Most manufacturers offer an analysis to save energy in the existing server environment.
Summary
According to the equipment manufacturer surveyed, an increase in the temperature in the data centre is possible and desirable. Increasing the temperature in the data center from 24°C to 27°C only saves a small amount of power, because the resulting increase in fan speed in the servers consumes part of the energy saved. This is also mentioned in the ASHRAE documentation.
