measures the efficiency of air-conditioners under a variety of conditions: several partial operational load ratios and coolant water temperatures similar to those in actual usage, to reflect seasonal changes in operational conditions.
345 kW per ton at the IPLV
level, in comparison to traditional chillers that operate at an average of 0.
In 1998, ARI Standard 550-1992 and ARI Standard 590-1992 (ARI 1992a and 1992b) were revised and joint into ARI Standard 550/590-1998 (ARI 1998), and the IPLV
formula was developed in a new way.
TABLE 1 Full load, part-load and IPLV
performance for chilled-water system vs.
Features include: highly efficient compressor design and efficient loading of compressor through unique logic for better energy efficiency; high IPLV
up to 7.
The advantages of the CSVH range are infinitely adjustable capacity control; improved ESEER, IPLV
and SCOP seasonal energy efficiency figures; integrated controller with complete monitoring of application limits; and Modbus interface for external communication.
AEDG = Advanced Energy Design Guide AEDG-SMO = Advanced Energy Design Guide for Small to Medium Office Buildings (see References) AP = Annual Payment COP = Coefficient of Performance (energy removed divided by work energy in consistent units i = Interest Rate per time period (i and n must be expressed in consistent time periods) IPLV
= Integrated Part-Load Value as defined by AHRI Standard 550/590.
Considerations for Chiller Life Cycle Evaluations Including Comparisons to ARI 550/590 IPLV
Integrated part load value per AHRI 550/590, kW/ton NPLV Non-standard part load value per AHRI 550/590, kW/ton RANGE Design tower entering minus leaving water temperature, [degrees]F PLR Plant part load ratio, current load divided by total plant design capacity TOPP Theoretical optimum plant performance WB Design wet-bulb temperature, ASHRAE 1%, [degrees]F WBDD55 Wet-bulb cooling degree-days base 55[degrees]F
In December 2009, the ASHRAE Journal [Geister & Thompson 2009] published a peer-reviewed feature-length article which, in part, took the position that a single-number IPLV
(Integrated Part-Load Value) or NPLV (Non-standard Part-Load Value) is an inadequate basis for sound purchasing decisions, especially in chiller plants with more than one chiller.
Measures implemented include high efficiency 500 ton (1760 kW) chillers with an IPLV
metric is intended to approximate typical seasonal performance as the load on the chiller varies.