P. Hollmuller1*, P. Gallinelli2, B. Lachal2, W. Weber2

1 SESUL / IDL, Universidade de Lisboa, Campo Grande, 1749-016 Lisboa, Portugal
2 Pole en Sciences de l’Environnement, Universite de Geneve, 1227 Carouge / Geneve, Switzerland
* Corresponding Author, pierre. hollmuller@fc. ul. pt

Abstract

Objective of this study is to compare the cooling potential of diverse passive cooling techniques linked to ventilation: controlled thermal phase-shifting (a recently discovered phenomenon), air-soil heat exchangers, evaporative cooling, and direct night cooling. The potential of these techniques is investigated for the case of an administrative building located in a moderate climate, with a specific attention to urban versus rural location, as well as normal versus extreme summer (of type 2003). Simulated building response is analyzed for a variety of constructive and operational configurations (solar protection, thermal mass and insulation, internal gains), in free floating mode as well as with auxiliary cooling backup. Keywords: passive cooling, ventilation, building simulation.

1. Introduction

In most parts of Europe, electricity demand for air-conditioning is in rapid increase. Limitation of this demand requires as well adequate architectural and constructive measures (reduction off the solar and internal gains, access to the thermal mass), as development of passive techniques.

Subject of a recent discovery, controlled thermal phase-shifting of the day/night oscillation carried by an airflow is a promising phenomenon for cooling with very low electric consumption: by delaying the cool night peak by 8-12 hours, almost without dampening, latter becomes available in the middle of the day, when the demand for cold in the building is at its maximum.

In spite of its attractive temporal specificity, latter technique must be compared with other passive cooling techniques, in particular those which also make use the ventilation system (night ventilation, buried pipe systems, evaporative cooling). As for all of these techniques, the effective cooling potential further intrinsically relates to the building design and response.

Objective of this study is to clarify above mentioned points for the case of administrative buildings, located in moderated climates, as investigated here on base of a series of meteorological datasets for the Geneva region.

This paper resumes the findings of a research financed by the Swiss Department of Energy.