Table 1 Parameters for Case Study of Downhole Thermoelectric Power Generation.

Tubing(steel) outer diameter

0.089

m

Tubing(steel) inner diameter

0.076

m

Casing(steel) outer diameter

0.244

m

Casing(steel) inner diameter

0.224

m

Injection pipe(vacuum insulated steel pipe) outer diameter

0.041

m

Injection pipe(vacuum insulated steel pipe) inner diameter

0.035

m

Wellbore depth

3500

m

Packer depth

3000

m

Coaxial heat exchanger length

500

m

Geothermal gradient

0.035

°C/m

Surface temperature

21

°C

Reservoir temperature

126

°C

Cold fluid injection temperature

20

°C

Cold fluid injection rate

500

m³/d

Fluid diversion ratio

1

/

Water specific heat capacity

4.18

kJ/(kg K)

Thermal conductivity of formation

2.42

W/(m K)

Thermal conductivity of insulation material (nano-SiO₂ aerogel)

0.06

W/(m K)

Thermal conductivity of casing (steel)

43.25

W/(m K)