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Energy efficiency measures - Commercial - Pumps - Variable speed / Germany

Case study assignment

Several pools at a large spa are fed by a 16 kW pump with throttle control. Energy audits show that throttle control may be wasting energy.

Base case
  • 16 kW energy efficient variable flow pump feeds a swimming pool
  • Load factor is 80%, operation 60 h/w
  • Pump operates at near full capacity with an overall efficiency of 65%
  • Pump discharge is adjusted by throttling
  • Electricity rate €0.097/kWh
Proposed case
  • Replace throttle flow control by a frequency controller to regulate the power output of the pump
  • Cost of variable speed control €3,500
Prepare a RETScreen study, documenting any assumptions that you are required to make, and report on the significant conclusions from this analysis.

Solution

The worked-out solution is the data file selected from within the RETScreen Project Database. The user automatically downloads the Project Database file while downloading the RETScreen software.

Similar project

Facilities with an all-year need for heat and electricity like public baths are a perfect application for cogeneration and energy efficiency. The Leuze Spa, in Germany, replaced its old steam-based district heating system with a combined heat and power plant. In the process, instead of using throttle control to reduce the flow from the pump feeding the pools, a frequency controller was used to regulate the power of the pump, saving considerable energy.

Real project (254 KB)