Integrated design and control of full sorption chiller systems

Thermally-driven sorption chillers offer a sustainable alternative to compression chillers. However, the expected benefits of sorption chillers are often not realised in practice due to high electricity consumption of auxiliaries, such as pumps and fans. To obtain an overall optimal full sorption chiller system, we propose a method for integrated optimisation of design and control. The proposed method applies dynamic optimisation to identify optimal control for each investigated system design. Thus, each design is evaluated under optimal control regarding a problem-specific objective, such as electrical efficiency or total costs. We illustrate the method for a case study of a solar-thermally-driven adsorption chiller system. The results are compared to an established design method and nominal control: optimising for electricity demand allows to increase the electrical energy efficiency ratio (EER) by one order of magnitude. When optimising for total costs, optimal control increases the energy efficiency by a factor 4 and decreases the total costs by 28% to 0.13 EUR/kWh. Moving to a cost-optimal design further increases the energy efficiency by 50% to 16.2 and reduces the total costs by another 8%. Thus, the proposed method allows for efficient integrated design and control of full sorption chiller systems. •Integrated design and control of full sorption chiller systems.•Dynamic optimisation of control to achieve maximal electrical efficiency.•Increase of electrical efficiency by one order of magnitude.•Cost-efficient system design considering investment and operating costs.