Evaluation of closed-loop U-Tube deep borehole heat exchanger in the Basal Cambrian Sandstone formation, Alberta, Canada

Geothermal Energy

Science – Society – Technology

Table 2 Wellbore material properties (Gallup 2003; Engineering Toolbox 2003, 2005, 2008, 2018; Kaya and Hoşhan 2005; Thorbjornsson 2017)

Object	Dimensions and other properties	Material	Thermal conductivity, W/m K
Tubing	Inner diameter 0.163 m	Carbon steel	44.96
	Outer diameter 0.168 m
	Roughness 0.0001
Insulation	Outer diameter 0.173 m	Calcium silicate	0.03
Casing	Outer diameter 0.23 m	Carbon steel	44.96
Annulus	Outer diameter 0.245 m	Water	0.66
Cement	Outer diameter 0.3 m	Cement	0.35