Enhanced geothermal systems (EGS) using CO2 as working fluid—A novel approach for generating renewable energy with simultaneous sequestration of carbon

TLDR: In this article, the authors evaluated thermophysical properties and performed numerical simulations to explore the fluid dynamics and heat transfer issues in an engineered geothermal reservoir that would be operated with CO2.

About: This article is published in Geothermics.The article was published on 2006-08-01 and is currently open access. It has received 503 citations till now. The article focuses on the topics: Enhanced geothermal system & Geothermal energy.

Figures

Figure 1. Phase states of CO2.

Figure 3. Specific enthalpy of CO2 (left) and water (right) in units of kJ/kg, as function of temperature and pressure.

Figure 2. Ratio of fluid density to viscosity in units of 106 sm-2 for CO2 (left) and water (right).

Figure 6. Temperature-pressure conditions for isenthalpic flow of CO2 in a 5000 m deep production well, for different downhole temperatures and pressures.

Table 1. Density, compressibility, and expansivity of CO2 and water at selected (T, P)conditions.

Figure 5. Temperature-pressure conditions for isenthalpic flow of CO2 in a 5000 m deep injection well, for different wellhead temperatures and pressures.