3.4 Electrical and Mechanical Management

What is it?

Being in control over the electrical and mechanical systems in the data center is crucial to have the right capacity at the right time. Therefore it is required to collect performance and capacity measurements and use them to make your short and long term plans.

You have to collect certain metrics to understand the installed capacity and how that is actually used. From an energy efficiency point of view you should collect these metrics:

  • Power draw and energy consumption of the transformer, humidifier, cooling heat pump and fans, UPS, PDU, etc...

Power and energy metrics of at least the topics on the left are needed to understand where the energy goes. What does the power train look like, where are energy losses, what are the major consumers, who uses the energy, etc. When you have this data up to the real consumers of the energy you have the picture of energy capacity utilization. Compare it to the maximum available capacity and watch the trend over time to be prepared for capacity shortage and for over-capacity.

  • Air temperatures leaving and entering the CRAC units and entering and leaving the IT racks

Most of the energy consumed by the facility equipment is for cooling air. When you monitor the temperatures you can easily increase the temperature and see the impact. Adjust air flows and see what happens. How does the new blade system or that high-density rack impact the temperatures? And when it does, see if other measures can be taken than just lowering the temperature and consuming much more energy. An average of 3% can be saved on cooling cost per degree Celsius.

  • Humidity

Humidifiers can use a lot of energy. Is it really needed to have one? Have you had a look at all factors that influence the humidity in your data center? Aren't your CRAC units drying the air and therefore keep the humidifier working and waisting energy? Have a look around, take measurements, look at the cooling plates inside the CRAC units and investigate what kind of air is brought into the data center via doors and decide if the energy consumed by the humidifier is well spent.


Why should you care?

A data center’s cooling systems and electrical systems are designed and build with certain scope and future plan in mind, while trying to build in flexibility and predict hardware trends on IT side. A good example is the introduction of blade systems. That can be an excellent choice for IT but a nightmare for a 7 year old data center to run this power hungry and hot spot creating piece of IT equipment.

In any optimization scenario, where IT and facility optimize KPIs in this model, you must have measurements of the “old times” and the new and improved configuration. Otherwise you will not be able to evaluate the effect of the change nor plan additional changes to IT and the facility.


How does it relate to the other items in the model?

Which KPI’s are directly related to this KPI?

  • KPI’s DCiE, Bypass and Recirculation require this KPI to improve. In combination with the capacity management process the capacity and settings of facility equipment can improve.
  • KPI Change and Configuration Management is supported by this KPI to record and store capacity data of the devices.
  • KPI Product Lifecycle Management requires this KPI to understand the actual utilization of the devices. It is input to determine the operational value and to learn what to do when the device needs replacement.
  • KPI Capacity Management is the process that uses this KPI as its input to understand the past, the current utilization and the future utilization considering stable development.
  • KPI Service Level Management matches this KPI to the expectations that are agreed in the service levels.