Installing IMO Jaguar CUB inverter drives saved 40% of a pool’s pumping costs; significantly reduced pump-room noise levels; improved flow rates;  increased filter life, and improved water quality.

The application was the re-circulating pumps for the main pool and spa pool in the Brands Hatch Thistle Hotel.  Both motors were running at full speed and flow rates were controlled by valves. The proposal was to install IMO Jaguar CUB variable speed drives to slow the pump speeds during daytime and night time running when the pumps are not required to operate at full capacity.

By adjusting the motor/pump speed to match demand efficiency is improved by up to 50%; wear and tear on the equipment is reduced; filters last longer, and water quality improves because water is not being forced through the filters unnecessarily.

Cube Law

Due to the cube law it is relatively simple to estimate the energy savings available by reducing a motor’s speed.  Fitting inverter drives to ac motors controlling fans and pumps can save considerable amounts of money. This is because the load follows what is termed the cube law, which simply means any reduction in motor speed reduces the power by the same factor, cubed, i.e. the reduction in power absorbed for just a 5% reduction in motor speed is shown by (1-(0.95×0.95×0.95)*100) = 14.3% saving: 10% by more a 27% saving and 20% by almost half..

To ensure the swimming and spa pool operator understood the proposal, IMO engineers visited the site and conducted a full energy reduction survey and suggested the installation of a Jaguar CUB inverter drive to both the swimming pool and spa pool pump motors.

Energy savings

The typical 24 hour power consumption of the pool pump at fixed speed was 73kWh and an estimated running current of 5.4 Amps.   After the Jaguar CUB was installed there was a 38% fall to 47kWh (based on a 40Hz running speed during daytime and 30Hz during the evening). Over the same 24Hr period the current used during normal operation was 2.7 Amps in variable speed operation which is a 50% reduction in the current absorbed.

Similarly, the spa pump in fixed speed operation showed that the estimated power consumption over a 24Hr period was 44kWh with an average current during the same period of 2.6Amps.  After the Jaguar CUB was installed, estimated power consumption over a 24Hr period was 26KwH, approximately 41% reduction in the power used (based upon a 40Hz running speed during daytime and 30Hz during the evening). Over the same 24Hr period the current fell to 1.5 Amps, again a 41% reduction in the power absorbed.

In addition to IMO being a well recognised supplier, they also offer a 5 year guarantee of the product.  Working with IMO Jaguar, 999 Inverters offers an inverter loan service to demonstrate energy savings and payback periods.

If you would like more information, send us a comment or contact us at:

Tel:  0116 2999 222
Fax: 0116 2999 223
Email: enquiries@999inverters.com
By Post: 999 Automation
Ross Walk
Leicester
LE4 5HA