Abstract:
The world requires more and more energy every day. While traditional sources of energy
are near exhaustion, renewables like geothermal energy provide immense promise.
Geothermal energy is the heat generated deep within the earth's core and can be extracted
from the crust with abandoned oil and gas wellbores. Water is sent down the wellbore,
where it absorbs heat and travels back to the surface, which is later turned to steam to
produce power. Geothermal energy extraction leaves a lot to be desired. The efficiency of
the current systems isn’t desirable. Of the two available technologies, CLGS (Closed-Loop
Geothermal System) and OLGS (Open-Loop Geothermal System), CLGS provides an
opportunity to retrofit oil and gas wells, which makes them feasible in terms of cost and
accessibility. The studies that have been conducted so far indicate that water is the better
heat transfer fluid overall. To enhance the efficiency of the CLGS, an understanding of the
entire wellbore system must be gained. A simulation approach provides a detailed analysis
of all the sections of the geothermal system.
The results reveal significant heat losses from the hot fluid after reaching the surface.
Installation of insulation improves performance drastically. Changing the materials shows
further performance improvements. But different materials have different drawbacks.
Insulation thickness also plays a significant role in heat retention and changes the flow
properties. Studying all of the parameters will result in an efficient geothermal system that
can be utilized in abandoned wellbores to provide more energy to the world.
