Effect of anthropogenic heat sources in the shallow subsurface at city-scale

Monika J Kreitmair,Ruchi Choudhary,Ricky L Terrington,Gareth J Farr,Asal Bidarmaghz,Nikolas Makasis,Johanna M Scheidegger,J.S Mccartney,I Tomac

doi:10.1051/e3sconf/202020507002

Monika J Kreitmair, Ruchi Choudhary + Show 7 more

Open Access

https://doi.org/10.1051/e3sconf/202020507002

Copy DOI

Abstract

Rapid rates of urbanisation are placing growing demands on cities for accommodation and transportation, with increasing numbers of basements and tunnel networks being built to meet these rising demands. Such subsurface structures constitute continuous heat sources and sinks, particularly if maintained at comfortable temperatures. At the city-scale, there is limited understanding of the effect of heat exchange of underground infrastructures with their environments, in part due to limited availability of long-term underground temperature data. The effects of underground temperature changes due anthropogenic heat fluxes can be significant, impacting ventilation and cooling costs of underground spaces, efficiency of geo-energy systems, quality and quantity of groundwater flow, and the health and maintenance of underground structures. In this paper we explore the impact of anthropogenic subsurface structures on the thermal climate of the shallow subsurface by developing a heat transfer model of the city of Cardiff, UK, utilising a recently developed semi-3D modelling approach.

Highlights

Growing population sizes and the resulting requirements on infrastructures within cities are creating an increased demand on the shallow subsurface for competing uses i.e. for energy applications, living spaces, and commercial structures
It was selected due to a considerable number of temperature measurements being available within this area over the course of several years, courtesy of the British Geological Survey (BGS)
Measurements were taken in boreholes throughout the city, measuring at various depths in the shallow subsurface

Summary

Introduction

Growing population sizes and the resulting requirements on infrastructures within cities are creating an increased demand on the shallow subsurface for competing uses i.e. for energy applications, living spaces, and commercial structures. These uses inevitably generate and consume heat from the surrounding ground. Less understanding exists of the effects of heat exchange between underground infrastructures and their environment at the city-scale, in part due to limited availability of long-term temperature data. Rivera et al [3] showed that raised urban ground temperatures in central Europe could reduce the length required for a given heating power supply by 4 m.

Methods

Results

Conclusion