Various metrics have been developed over time for optimizing the supporting facilities of a data center such as the power and cooling infrastructure. Metrics such as PUE, WUE etc. have made inroads in the data center industry for many years and, although often abused, they have helped the industry to create awareness and improvements.

However, it is EPI’s stand that the best savings can be made at the computer room level. The reason is simple because of PUE, for every kW on the computer room floor, there will be a multiple of it at the facility entry.

Another issue in the industry is that there tends to be a habit of overdesigning and underutilization, causing excessive wastage of valuable resources as well as creating negative impact on expected investment returns.

Furthermore, MTDCs (Multi Tenanted Data Centers) could end up being penalized due to oversubscribed, and underutilized, computer room utilization which will have an impact on the overall PUE, WUE and other energy efficiency factors that the MTDC might be required, sometimes by law, to achieve.

EPI has developed a new metric, CRUR^® (Computer Room Utilization Ratio), to address this issue. Data center owners, operators and end-users can use CRUR^® to optimize the computer room utilization right now. They can also use it for trend analysis which could positively impact the design criteria for data centers to be built in future, resulting in better efficiency, utilization and return on investment.

CRUR^® is the first ever metric designed to measure and optimize the core of many data center efficiency issues which is the computer room itself. It is clear that CRUR^®, together with metrics such as PUE, will create a positive impact on the environmental impact.

The scope of the CRUR^® metric is the computer room, and its direct supporting infrastructure which includes electrical (power), mechanical (cooling) and ICT.

The CRUR^® metric can be applied to IT, or facilities, or both. The three scopes are indicated respectively as:

CRUR_IT : Computer Room Utilization Ratio for IT components only

CRUR_F : Computer Room Utilization Ratio for Facilities components only

CRUR_ITF : Computer Room Utilization Ratio for IT & Facilities components

The organization can choose any one of the metrics depending on the business requirements and scope of control. For example, an Enterprise Data Center might prefer to implement CRUR_ITF as it has full control over both the data center facilities as well as the ICT infrastructure, whereas a commercial data center operator might prefer to only implement CRUR_F as they (might) have very little or no control over the ICT equipment deployed by their customers. Cloud providers might consider using the CRUR_ITF as they often have full control over both the facilities and ICT equipment.

There are several key advantages for data center operator/owners when applying CRUR^®:

1. Scope
   The organization can prioritize which scope is potentially having the biggest business or environmental sustainability impact.
2. Easy to implement
   CRUR^® metric is clearly defined in a free downloadable document. EPI provides fast response to any potential questions around specific cases for implementation via support@epi-ap.com.
3. Quick and easy to understand
   Like PUE, the CRUR^® metric provides a quick and easy to understand metric for the computer room and direct supporting facilities. It provides a quick insight on the presence of potential inefficiencies/waste, and in which areas.
4. Immediate optimization
   With the CRUR^® metric, the organization can very quickly determine where the biggest savings can be made and create a plan for optimization.
5. Capacity planning and optimization
   CRUR will assist with the capacity planning which is one of the most difficult tasks for data center staff. CRUR^® will provide clarity on which areas of the data center are running close to its maximum capacity.
6. Future planning
   Based on lessons learned from applying CRUR^®, organizations can plan for better capacity rollout out models avoiding costly oversizing for future data center projects.

Organizations can self-assess the CRUR^® metric. However, the organization must declare the scope (CRURIT/CRURF/CRURIT) and must state that the declared value is based on a self-assessment.

EPI and its authorized audit organizations are able to provide an official audit and certification for CRUR^®. Please contact sales@epi-certification.com for more information.

The CRUR workshops will allow you to understand the CRUR, why it is important and what benefits you can gain. The workshops are on-demand and they are free. Click here.