Energy saving All electric motors in KUBE®start arefrequency controlled; a fact that reduces the energy consumption by 30 – 50 %. In addition, unnecessary load and mechanical wear at start-up is avoided as the PLC provides an opportunity for soft-start of the machines. In addition, there is
considerable energy saving by using the integrated heat pump which, during normal operation, only needs 4-5 kW to maintain the water temperature at a determined level. If one assume an annual energy consumption of approximately 240 operative days and an average temperature increase of 7 °C from raw water, the energy consumption of KUBE®start 25 will be 50-55 % lower compared to a flow-through system with a heating pump. The investment costs including installation costs will be in the same order as for KUBEstart®25 and aflow-through system fitted with a modern heat pump.
Illustration 1. Comparison of the operational costs for KUBE®start 25 and a flowthrough system with a modern heat pump in a situation where the facility has 240 operative days a year with a water consumption of 4200 litres/min and an average temperature increase of 7 °C.
The main reason of the low energy consumption in KUBE®start 25 is the low
addition of new water that needs heating. Moreover,the energy used pumping water for circulation is converted into heat. Overall the energy in KUBE®start 25 is very well utilized. The low energy consumption in KUBE®start 25 will result in considerable lower operating costs compared to a facility with flow through system and heating pump (graph 1). Over a period of 5-6 years this difference will sum up to approximately 1 million NOK assuming power costs of 1.25 NOK/kWh.