A method to reduce European chiller hourly load curves to a few points

EECCAC is an EU funded project, where twelve participants (National Energy Agencies, Manufacturers, University laboratories and Electric utilities) from eight countries gathered to identify the most suitable measures to achieve market transformation in the direction of energy efficiency of central air conditioning systems in Europe. Its basement was the Eurovent manufacturers wish to develop a seasonal performance index for chillers in Europe, so as to compare their performances not only on full load, which is not representative of chiller average performances, but also on part load.
To that extent, a method has been developed that enables to reduce the chiller hourly load curve to N triplets (weighting coefficient, outside air or water temperature, load ratio). In order to minimise the number of testing points, as well as to adopt a format compatible with the existing American IPLV standard, 4 points have been kept. The reduction is applied to annual hourly load curves, results of the DOE software simulation of an existing office building for four different air conditioning systems and within three different climates (London, Seville, Milan). Finally, the bias introduced on the seasonal efficiency by the reduction is compared to the uncertainty of measurement of the chiller seasonal performance.