Water Cooled Chiller Efficiency Calculation

For example what size chiller is required to cool 40gpm from 70 f to 58 f t f 70 f 58 f 12 f.

Water cooled chiller efficiency calculation.

The average temperature is 48 2 f so we need to calculate the water properties at. In fact in most cases i doubt we can make peak efficiency at full load operation let alone at part loads. The performance of this standard unit is based on ashrae standard 90 1. In practice the cooling tower efficiency will be in between 65 to 70.

Calculations assume that efficiency ratings entered by the user are based. Base model values represent a 100 ton air cooled electric chiller operated for 2 000 full load hours per year with an eer of 9. The equivalent ton on the cooling tower side actually rejects about 15000 btu h due to the heat equivalent of the energy needed to drive the chiller s compressor. A cooling tower ton is defined as.

In summer season the ambient air wet bulb temperature raises when compared to winter season so cooling tower efficiency limiting in summer season. With this information you can calculate chiller efficiency in terms of the energy efficiency ratio or eer and the coefficient of performance or cop for chillers. Water cooling system difference between. 2 500kw 460kw 5 4 so the cop is 5 4.

1 cooling tower ton 1 tons evap 1 tons cond x 1 25 15000 btu h 3782 k calories h 15826 kj h 4 396 kw. In the ideal case the cold water temperature will be equal to the wet bulb temperature. This equivalent ton is defined as the heat rejection in cooling. Performance of chiller is measured at different loading condition say 100 75 50 25 and iplv or nplv is calculated.

The flow rate of chilled water into the evaporator is measured as 12 649ft3 h and the chilled water inlet temperature is 53 6 f the outlet temperature is 42 8 f. It s important to remember that the cop of a chiller varies with the cooling load on a chiller and that each chiller has a. Cooling tower efficiency. How to calculate the efficiency of a chiller imperial and metric.

40gpm x 60 x 8 33 x 12 f 239 904 btu hr. The chiller system is recirculating 40 gallons per minute of water that is chilled by 24 degrees f and using 24 8 kw hr of electricity to produce the refrigeration. For water chilling packages covered by this standard the iplv or nplv shall be calculated as. Calculation of iplv and nplv.

I just read the article real efficiencies of central plants may 2007 and completely agree that few chiller plants attain the efficiency kilowatts per ton that we would like to see. You have the ideal size for your needs. Oversize the chiller by 20 ideal size in tons tons x 1 2. Calculate tons of cooling capacity tons btu hr.

Default values the values pre loaded into the calculator represent average operating conditions in the federal sector. I am interested in the statement made at the end of the article. This means that for every 1kw of electricity you put into the machine you will produce 5 4kw of cooling. So for evaluating chiller efficiency at different part load condition iplv or nplv is calculated.

The calculation of cooling tower efficiency involves the range and approach of the cooling tower.