Water Cooled Chiller Efficiency Calculation

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.

Water cooled chiller efficiency calculation.

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. 2 500kw 460kw 5 4 so the cop is 5 4. A cooling tower ton is defined as. 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. The average temperature is 48 2 f so we need to calculate the water properties at. This equivalent ton is defined as the heat rejection in cooling. 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.

This means that for every 1kw of electricity you put into the machine you will produce 5 4kw of cooling. 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. Cooling tower efficiency. Cooling tower efficiency is limited by the ambient wet bulb temperature.

The performance of this standard unit is based on ashrae standard 90 1. For example what size chiller is required to cool 40gpm from 70 f to 58 f t f 70 f 58 f 12 f. Calculation of iplv and nplv. Now lets look at how to calculate the cooling capacity of a chiller in imperial units.

In fact in most cases i doubt we can make peak efficiency at full load operation let alone at part loads. Default values the values pre loaded into the calculator represent average operating conditions in the federal sector. 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. So for evaluating chiller efficiency at different part load condition iplv or nplv is calculated.

Calculate tons of cooling capacity tons btu hr. The calculation of cooling tower efficiency involves the range and approach of the cooling tower. I am interested in the statement made at the end of the article. 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.

In practice the cooling tower efficiency will be in between 65 to 70. How to calculate the efficiency of a chiller imperial and metric. For water chilling packages covered by this standard the iplv or nplv shall be calculated as. 40gpm x 60 x 8 33 x 12 f 239 904 btu hr.

Oversize the chiller by 20 ideal size in tons tons x 1 2. Water cooling system difference between. In summer season the ambient air wet bulb temperature raises when compared to winter season so cooling tower efficiency limiting in summer season. Cooling tower efficiency.

In the ideal case the cold water temperature will be equal to the wet bulb temperature.