Modelling an unconventional closed-loop deep borehole heat exchanger (DBHE): sensitivity analysis on the Newberry volcanic setting

Geothermal Energy

Science – Society – Technology

Table 4 Key geological settings in support of Fig. 2 (left)

Key	Geological name	Altitude range	Thermodynamic properties^a
1.	Newberry–Deschutes (upper)	+ 1600 m to + 1400 m	\(\rho =\) 2700 kg/m\(^{3}\)^b \(c_{\text{P}} = 1000 {\text{ J}/{\text{kg}}}\,^{\circ }\text {C}\)^b \(\varPhi = 0.2\; (20\%\)) \(K = 0.15\times 10^{-11}\text { m}^{2}\) \(\lambda = 1.7 \,{ \text{W}/{\text{mK}}}\)
2.	Newberry–Deschutes	+ 1400 m to + 300 m	\(\varPhi = 0.1\) (10\(\%\)) \(K = 0.1\times 10^{-16}\text { m}^{2}\) \(\lambda = 1.8 \,{ \text{W}/{\text{mK}}}\)
3.	John Day	+ 300 m to − 800 m	\(\varPhi = 0.05\) (5\(\%\)) \(K = 2.6\times 10^{-16}\text { m}^{2}\) \(\lambda = 2.15\; {\text{W}/{\text{mK}}}\)
4.	Intruded John Day	− 800 m to − 1500 m	\(\varPhi = 0.03\) (3\(\%\)) \(K = 0.5\times 10^{-17}\text { m}^{2}\) \(\lambda = 2.15\; {\text{W}/{\text{mK}}}\)

^aAll properties apart from \(\rho\) and \(c_{\text{P}}\) are cited from Sonnenthal et al. (2012)
^bAll rock properties have identical \(\rho\) and \(c_{\text{P}}\) variables, quoted from Sammel et al. (1988)