Major energy savings achieved

Eton Associates Limited, the Docklands based building services control specialists have been awarded an order by Canary Wharf Management to upgrade 36 Mammoth packaged air handling units in two buildings occupied by Barclays Capital.

Each floor of the building has three of the Mammoth air handling units which are used to deliver air to the floor at 11°C. Each Mammoth has a fan with variable speed drive and two reciprocating refrigeration compressors.

The aim of the project was to improve the stability of the supply air temperature and upgrade the reciprocating compressors and replace the CFC R22 refrigerant with the more environmentally friendly R417A.

Kevin Bright, Eton’s refrigeration specialist selected screw type compressors and developed a replacement strategy which would ensure that the building operation would not be affected in any way.

A floor was selected as a test and following a period of pre fabrication the compressors were installed and commissioned over a weekend without affecting the supply of air to the floor at any time.

Measurements were taken before and after the upgrade and proved there was a saving in electricity consumption of 30.7% which equates to 14kWatts at each Mammoth.

When the project is completed the estimated saving alone will be 3300mW hours each year saving approximately a staggering £185,000, and a further £90,000 in the annual cost of keeping 72, 15 year old compressors operational.