Nuclear District Cooling System: Evaluation and Optimization

Hussein Abdulkareem Sale ABUSHAMAH

Doctoral thesis

Optimisation of Renewable and SMR Energy Mix

Abstract:

The air conditioning sector is one of the major contributors to electricity consumption and carbon emissions in many regions over the world. For example, in hot climate regions such as the Gulf Cooperation Council (GCC), about half of the annual generated electricity is for air-conditioning, leading to significant carbon emissions. The widely adopted scenario is burning the fuel to produce heat, converting the heat to electricity, transporting the electricity through HV/MV/LV grids to supply electric-driven cooling systems. Proceeding in this manner puts pressure on power grids, raises investments for expanding the electrical infrastructure, drives up carbon emissions, and leads to more energy losses due to unwanted energy conversions and transmissions. This study presents a carbon-free thermally driven district cooling system to overcome these issues of the electric-driven cooling scenario. The proposed system here employs a nuclear heat-only reactor called Teplator as a carbon-free primary heat source driving absorption chillers. This idea is techno-economically evaluated from two different perspectives, namely, the energy policy viewpoint and the investor's point of view. First, from an energy policy viewpoint, adopting the proposed system is compared to the electric scenario based on levelized values for cooling demand, costs, and energy consumption without dealing with details of a specific case-based design or operation. From an investor's viewpoint, a detailed method is developed to optimize the proposed system's design and operation, including the heat transmission system and a centralized cooling plant, for supplying an hourly-based demand model. A competition-based optimization process is performed by including several alternative units, such as thermal energy storage, gas boilers, and compression chillers, which simultaneously also checks the electric-driven option. The developed models are coded in MATLAB and simulated. The results confirm the proposed system's superiority in cost, electricity, and carbon emission saving compared with fossil fuel-based electrically driven district cooling systems. However, the performed sensitivity analyses show that this superiority could be limited as the electricity price decreases and heat transmission pipeline length increases.

Abstract:

The air conditioning sector is one of the major contributors to electricity consumption and carbon emissions in many regions over the world. For example, in hot climate regions such as the Gulf Cooperation Council (GCC), about half of the annual generated electricity is for air-conditioning, leading to significant carbon emissions. The widely adopted scenario is burning the fuel to produce heat, converting the heat to electricity, transporting the electricity through HV/MV/LV grids to supply electric-driven cooling systems. Proceeding in this manner puts pressure on power grids, raises investments for expanding the electrical infrastructure, drives up carbon emissions, and leads to more energy losses due to unwanted energy conversions and transmissions. This study presents a carbon-free thermally driven district cooling system to overcome these issues of the electric-driven cooling scenario. The proposed system here employs a nuclear heat-only reactor called Teplator as a carbon-free primary heat source driving absorption chillers. This idea is techno-economically evaluated from two different perspectives, namely, the energy policy viewpoint and the investor's point of view. First, from an energy policy viewpoint, adopting the proposed system is compared to the electric scenario based on levelized values for cooling demand, costs, and energy consumption without dealing with details of a specific case-based design or operation. From an investor's viewpoint, a detailed method is developed to optimize the proposed system's design and operation, including the heat transmission system and a centralized cooling plant, for supplying an hourly-based demand model. A competition-based optimization process is performed by including several alternative units, such as thermal energy storage, gas boilers, and compression chillers, which simultaneously also checks the electric-driven option. The developed models are coded in MATLAB and simulated. The results confirm the proposed system's superiority in cost, electricity, and carbon emission saving compared with fossil fuel-based electrically driven district cooling systems. However, the performed sensitivity analyses show that this superiority could be limited as the electricity price decreases and heat transmission pipeline length increases.

Keywords

District Cooling, Nuclear Heat-Only Small Modular Reactors, Teplator, Electricity and Carbon Emission Saving, Power Grid, Optimization.

Language used: English

Date on which the thesis was submitted / produced: 9. 11. 2023

Accessible from:: 31. 12. 2999

Thesis defence

• Supervisor: Prof. Ing. Radek Škoda, Ph.D.

University of West Bohemia

Faculty of Electrical Engineering

Doctoral programme / field:
Electrical Engineering and Information Technology / Electrical Engineering and Information Technology