Achieving Cooler Soil as an Effective Heat Sink for Earth-to-Air Heat Exchanger (EAHE) Cooling Technology in Malaysia Tropical Climate

Aliyah Nur Zafirah Sanusi,Aidil Azlan Ahmad Zamri

doi:10.4236/nr.2014.513069

Abstract

This research is intended to explore the capacity of Malaysia soil in becoming a more effective heat sink for the application of Earth-to-Air Heat Exchanger (EAHE) Cooling Technology in Malaysia. EAHE Cooling Technology consists of buried pipes underground where the ambient air is channeled through from the pipe inlet and produces cooler air at its outlet. Within the buried pipes, heat exchange process occurs between the air and the soil that surrounding the pipe. This building cooling technology has been applied in many countries, mostly in temperate or hot and arid climate where the diurnal temperature is large. However, minimal resources were found on the study of EAHE application to buildings in Malaysia, hence there is room to develop. A parametric study on EAHE cooling application in Malaysia was done through field experiment and concluded that among many parameters affecting the technology performance, the soil temperature which surrounded the pipe was the most influential factor. The study recommended to further reduce the soil temperature to achieve a cooler outlet temperature. In response to that, this research conducted a parametric study of soil temperature under three different soil surface conditions: bare, shaded with timber pallettes and insulated with used tyres at 1.0 m and 1.5 m underground. The data was logged for a month and the result has shown significant reduction in the soil temperature underground below the shaded and insulated soil surface as compared to below bare soil surface condition. The insulated soil surface produced the best result where the soil temperature was reduced up to 26.9°C. The main contribution of this paper is to highlight that the soil surface treatment can be used to reduce solar heat gain within the soil underground and thus improving the performance of EAHE Cooling Technology particularly for the application in Malaysia tropical climate.

Highlights

Urban Heat Island (UHI) issue with maximum temperature rising up to 40 ̊C that leads to human thermal comfort is affecting Malaysia energy consumption [1]
This research is intended to find possible solutions in applying a better alternative building cooling system that would lead to mitigating the Urban Heat Island (UHI) issue and reduce energy consumptions in the future and Earth-to-Air Heat Exchanger (EAHE) cooling technology is further explored in becoming the better alternative building cooling in Malaysia
EAHE Cooling Technology consists of buried pipes with two ends: pipe inlet and outlet, which act as a vehicle to channel ambient air into its inlet through to its outlet

Summary

Introduction

Urban Heat Island (UHI) issue with maximum temperature rising up to 40 ̊C that leads to human thermal comfort is affecting Malaysia energy consumption [1]. This research is intended to find possible solutions in applying a better alternative building cooling system that would lead to mitigating the Urban Heat Island (UHI) issue and reduce energy consumptions in the future and Earth-to-Air Heat Exchanger (EAHE) cooling technology is further explored in becoming the better alternative building cooling in Malaysia. Many researchers have agreed to similar conclusion that the EAHE pipe outlet temperature could be reduced for building cooling through the increasing pipe length, decreasing pipe diameter, decreasing air flow rate within the pipe and increasing pipe burial depths until the maximum of 4 m underground [3] and [4]. The EAHE Cooling Technology is rarely applied in Malaysia and yet to be explored further

Objectives

Methods

Results

Conclusion