Results 1 to 3 of 3
  1. #1
    Join Date
    Sep 2003
    Location
    ISRAEL
    Age
    72
    Posts
    4,266
    Rep Power
    46

    Helpful information



    Converting kW/ton to COP or EER
    How to convert between kW/ton, COP and EER
    The efficiency of chillers depends on the energy consumed. Absorption chillers are rated in fuel consumption per ton cooling. Electric motor driven chillers are rated in kilowatts per ton cooling.

    KW/ton = 12 / EER
    KW/ton = 12 / (COP x 3.412)
    COP = EER / 3.412
    COP = 12 / (KW/ton) / 3.412
    EER = 12 / KW/ton
    EER = COP x 3.412


    If a chillers efficiency is rated at 1 KW/ton, the COP=3.5 and the EER=12

    Cooling Load in - kW/ton
    The term kW/ton is common used for large commercial and industrial air-conditioning, heat pump and refrigeration systems.

    The term is defined as the ratio of the rate of energy consumption in kW to the rate of heat removal in tons at the rated condition. The lower the kW/ton the more efficient the system.

    kW/ton = Pc / Er (1)

    where

    Pc = energy consumption (kW)

    Er = heat removed (ton)

    Coefficient of Performance - COP
    The Coefficient of Performance - COP - is the basic unit less parameter used to report the efficiency of refrigerant based systems.

    The Coefficient of Performance - COP - is the ratio between useful energy acquired and energy applied and can be expressed as:

    COP = Eu / Ea (1)

    where

    COP = coefficient of performance

    Eu = useful energy acquired

    Ea = energy applied

    COP can be used to define both cooling efficiency or heating efficiency as for a heat pump.

    For cooling, COP is defined as the ratio of the rate of heat removal to the rate of energy input to the compressor.

    For heating, COP is defined as the ratio of rate of heat delivered to the rate of energy input to the compressor.

    COP can be used to define the efficiency at a single standard or non-standard rated condition or a weighted average seasonal condition. The term may or may not include the energy consumption of auxiliary systems such as indoor or outdoor fans, chilled water pumps, or cooling tower systems. For purposes of comparison, the higher the COP the more efficient the system.

    COP can be treated as an efficiency where COP of 2.00 = 200% efficient For unitary heat pumps, ratings at two standard outdoor temperatures of 47°F and 17°F (8.3°C and -8.3°C) are typically used.

    Energy Efficiency Ratio - EER
    The Energy Efficiency Ratio - EER - is a term generally used to define the cooling efficiency of unitary air-conditioning and heat pump systems.

    The efficiency is determined at a single rated condition specified by the appropriate equipment standard and is defined as the ratio of net cooling capacity - or heat removed in Btu/h - to the total input rate of electric energy applied - in watt hour. The units of EER are Btu/w.h.

    EER = Ec / Pa (1)

    where

    EER = energy efficient ratio (Btu/w.h)

    Ec = net cooling capacity (Btu/h)

    Pa = applied energy (w.h)

    This efficiency term typically includes the energy requirement of auxiliary systems such as the indoor and outdoor fans and the higher the EER the more efficient is the system.

    Chemi



  2. #2
    Join Date
    Dec 2004
    Location
    Weihai,China
    Posts
    807
    Rep Power
    20

    Smile Re: Helpful information

    thanks for your information.
    The COP of chiller is around 3.5 (kw/kw).Have you used high COP ones(may reach 4.6 or above? )
    I've heard about the so called ones ,but i've no seeing of them.
    any clues?

  3. #3
    subhash chandra's Avatar
    subhash chandra Guest

    Re: Helpful information

    Thanks
    It's great and very helpful.

Similar Threads

  1. information reqired
    By daba in forum Technical Speculations
    Replies: 2
    Last Post: 14-05-2006, 08:34 PM
  2. information on an old Air temp A/C
    By Bahaaeldeen in forum Refrigeration Books
    Replies: 3
    Last Post: 09-05-2006, 12:49 PM
  3. auxiliary components information
    By mohamed khamis in forum Tools and Calculators
    Replies: 2
    Last Post: 27-04-2006, 01:20 PM
  4. Information on Hussmann enviropacks
    By tonydeith in forum Supermarket Refrigeration
    Replies: 0
    Last Post: 25-04-2006, 01:22 PM
  5. Information on frost top prep table
    By kengineering in forum Commercial
    Replies: 15
    Last Post: 08-02-2006, 10:58 AM

Posting Permissions

  • You may not post new threads
  • You may not post replies
  • You may not post attachments
  • You may not edit your posts
  •