Share

Exergy analysis of conventional and low exergy systems for heating and cooling of near zero energy buildings.

Author(s) : DOVJAK M., SHUKUYAC M., KRAINER A.

Type of article: Article

Summary

The purpose of the study is to compare two heating and cooling (H/C) systems regarding individual thermal comfort conditions and rational building energy use. Real test room is firstly equipped with low exergy (LowEx) system (i.e. heating-cooling ceiling radiative panels) and secondly with a conventional system (i.e. electric heaters. cooling split system with indoor unit). Additional case presents a thermally non-insulated room equipped with a conventional system. Individual thermal comfort conditions are analyzed through the simulation of human body exergy balance (hbExB, human body exergy consumption (hbExC) rates and predicted mean votes (PMV) index. Measurements of energy use and control of temperature conditions are performed on an integrated control system (ICsIE) based on fuzzy logic. The results confirm that both systems create comfort conditions if the room is thermally well insulated. In case of non-insulated room there appears cool radiant exergy that often leads to discomfort conditions. More acceptable comfortable conditions (PMV closer to 0) do not always result in a lower hbExC rate. Individual characteristics with experimental conditions have a significant influence on separate parts of hbExB. LowEx system connected with ICsIE enables to set air temperature and mean radiant temperature and creates optimal thermal comfort conditions for individual user. The measured energy use for heating was by 11 to 27% lower for LowEx system than for the conventional system. The energy use for cooling was by 41 to 62% lower for LowEx system. The presented approach of reciprocal consideration of individual thermal comfort conditions and building energy use is important for the future design of H/C systems and for their application in near zero energy buildings.

Available documents

Format PDF

Pages: 453-461

Available

  • Public price

    20 €

  • Member price*

    15 €

* Best rate depending on membership category (see the detailed benefits of individual and corporate memberships).

Details

  • Original title: Exergy analysis of conventional and low exergy systems for heating and cooling of near zero energy buildings.
  • Record ID : 30006910
  • Languages: English
  • Subject: Environment
  • Source: Strojniski vestnik - Journal of mechanical Engineering - vol. 58 - n. 7-8
  • Publication date: 2012/07
  • DOI: http://dx.doi.org/10.5545/sv-jme.2011.158

Links


See the source

Indexing