Diamond Light Source

This case study outlines how ebm-papst, Cinque Energy Solutions and STULZ are working together to provide energy saving solutions to their customers. In this example one of the UK's leading scientific organisations dramatically reduced their cooling energy consumption, by simply upgrading their existing air-conditioning equipment to use ebm-papst EC fans.

Trial & Energy Analysis

In January 2013, the trial installation of one unit was carried out by Cinque Energy Solutions. The aim of the trial was to confirm the bespoke design and prove the potential energy saving and benefits to the customer. Initial results showed a 43% improvement in kVA compared with the original AC fans. For the trial the unit was not physically modified, which allowed the potential to revert back to the original set up if desired. It was agreed that for the complete upgrade that the floor of the CRAC unit would be opened up further to allow the new fans a less restrictive system resistance to increase efficiency further.

The trial unit was set up to match the previous airflow but due to the simplicity of the control of EC fans, a simple manual 0-10v controller was fitted to the CRAC unit to allow each unit to be tuned to the room requirements. Over the course of a few months the maintenance team was able to adjust the fan speed to optimise the solution even further.

Project Implementation

The upgrade of the 29 units was scheduled to be completed during a 'shutdown period' in August 2013. The complete upgrade had to be finished within a 2 week window so 2 teams from Cinque Energy Solutions were deployed to work on units simultaneously. All 54 fans were delivered to site and positioned near the units to cut down on delays during the conversion.

After the complete installation, the original unit which had previously been measured for the trial, was remeasured following the floor pan being opened up to the designed requirements. This in addition to the fine tuning of the fan performance gave the following improved results.

The improvement in kW's even with the skew of improvement in power factor (0.6 to 0.9) also gave an improved result compared to initial estimations.

Additional Benefits

As well as the significant energy saving achieved by converting to EC fans, other benefits also came out of the conversion which proved to be as important for the customer. Due to the sensitivity of the equipment being used in the Synchrotron, improvements in noise and vibration from using EC fans was also an advantage. The other benefits from the upgrade include:

• Extended fan life
• Extended unit life
• Reduced maintenance – no belts
• No belt dust being blown into the equipment rooms
• Controllability of cooling capacity
• Greater flexibility for capacity management

Conclusion

The successful completion of phase 1 of the EC upgrade has led to a 55 % energy saving from the original AC fans, bringing a £ 36k energy saving per annum as well as significantly reducing noise and vibration from the units being transmitted into other parts of the building. Phase 2 of the project, to convert the remaining STULZ cooling units is scheduled for upgrade at the next shutdown period.