Heating energy performance and part load ratio characteristics of boiler staging in an office building

Abstract

Commercial buildings account for significant portions of the total building energy in South Korea and thus a variety of research on the boiler operation related to heating energy in office buildings has been carried out thus far. However, most of the researches have been conducted on the boiler itself, i.e., the part load ratio characteristics and the corresponding gas energy consumption patterns are not analyzed in the existing studies. In this study, the part load ratio and the operating characteristics of gas boiler have been analyzed within an office building equipped with the conventional variable air volume system. In addition, the gas consumption among different boiler staging schemes has been comparatively analyzed. As a result, significant portions of total operating hours, heating load and energy consumption has been found to be in a part load ratio range of 0 through 40% and thus energy consumption is significantly affected by boiler efficiency at low part load conditions. This suggests that boiler operation at the part load is an important factor in commercial buildings. In addition, utilizing sequential boiler staging scheme can save a gas usage of about 7%. For annual heating energy saving, applying the sequential control boiler with a 3:7 proportion staging is considered to be the optimal control algorithm for maximum efficiency of boilers.

Key words： EnergyPlus; boiler; part load ratio; gas consumption; office building; boiler staging

Acknowledgments

This work was supported by the Korea Institute of Energy Technology Evaluation and Planning (KETEP) and the Ministry of Trade, Industry & Energy (MOTIE) of the Republic of Korea (No. 20163030111350), and the Human Resources Development of the Korea Institute of Energy Technology Evaluation and Planning (KETEP) grant funded by the Korea government Ministry of Trade, Industry & Energy (No. 20184030201900).

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