The Problem

A leader in the manufacture of High Density Polyethylene (HDPE) bottles for the food and drink industry wanted to reduce its Carbon footprint and save costs.
Having many Process Pumps – typical rating of 11-30KW,circulating water from the Chiller Units around the factory cooling manufacturing machines then back to the Chiller. If one pump cannot cope and the water is returning too hot, it is therefore necessary to bring in another pump and potentially wasting energy.
Following a successful trial it was discovered that there were major savings available using ABB inverter control on the Chiller pumps on site. This manufacturer proceeded with confidence to save over 60% following optimisation on over 20 Chiller pumps at a number of their sites.

Sentridge’s Solution

The existing Process and chiller pumps on site are currently controlled by Direct On Line starters, fixed speed with flow regulated by valve. This method of control uses more energy than necessary to achieve the required flow and is an ideal application for innovation and energy saving.
Potential savings are very good with quick payback times possible.

The Full Story

An energy appraisal was undertaken on the Process and chiller pumps which showed potential saving and prompt payback time. We installed a trial unit so that the local site manager could witness the savings for himself.

The Process and chiller pump’s energy consumption was monitored before and after. The ABB ACH550 used has many energy saving features, speed control and up to 25% lower harmonics with its integral Swinging choke. This ensures a low harmonic foot print as the choke is automatically tuned to the load conditions and that only the power needed for the process is delivered to the motor, running the pumps cooler and quieter.

The savings recorded was 49% energy saving when compared with traditional DOL starting method. This was improved on final installations and the average savings made was 60% with average paybacks of 9-10months.

Following analysis of the data and presentation of the results, 20 ABB ACH550 HVAC inverter drives (VSDs) with ActivFlow control were installed and valve control removed from the process. As a result, flow rates were matched automatically to the factory process requirements at any given time. By using this control method, the system will respond to any changes within the manufacturing process and keep the system at a constant temperature ensuring consistent product quality.