Al-Shirqat – Iraq Reducing Energy Demand in Iraq Buildings Using Shallow Geothermal
DOI:
https://doi.org/10.71285/icpt.v3i2.26Keywords:
Shallow geothermal energy, Building heating, Economic feasibility, Life cycle cost, Operating cost, Carbon emissionsAbstract
This study presents an economic and environmental assessment of a proposed shallow geothermal heating system for building applications under local climatic conditions in Iraq. The analysis was carried out for a room with a total heating load of 905 W, with the performance of the geothermal system compared with two conventional alternatives, namely: a fossil-fuel-based heating system and a direct electric heating system. The total electrical input power of the geothermal system included both the heat pump power and the auxiliary fan power, in order to reach a more realistic economic evaluation. The assessment relied on economic and environmental indicators including annual energy consumption, annual operating cost, life cycle cost, annualized cost, unit thermal energy cost, annual savings, and direct carbon dioxide emissions. The results showed that the geothermal system required a total electrical power of 340.67 W, and an annual electrical energy consumption of 2486.87 kWh/year. By adopting an electricity price of 0.18 USD/kWh, the annual electricity cost reached 447.64 USD/year, while the total annual operating cost reached 496.54 USD/year. As for the conventional fuel-based system, its annual operating cost reached 645.79 USD/year, which led to achieving annual savings of 149.25 USD/year in favor of the geothermal system, with a reduction in operating cost of 23.11%. The annual energy cost difference between the geothermal system and the direct electric heating system also reached 741.53 USD/year. From the environmental point of view, the amount of direct emissions from the conventional system reached approximately 1.41 ton CO₂/year, whereas the geothermal system produced no direct combustion emissions at the point of use. The results confirm that the proposed geothermal system represents an economically and environmentally applicable alternative in building heating applications under local conditions.
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