Optimization of integrated microturbine and absorption chiller systems in CHP for buildings applications.

摘要

This research investigates integrated microturbine and absorption chiller systems for commercial building applications with a focus on optimization of the selection and operation of such systems. Cooling, Heating and Power (CHP) systems have the potential for energy efficiency that can double that of traditional coal-burning power plants through the utilization of waste heat generated during the power production process. However, energy savings do not necessarily translate into cost savings because of various economic factors affecting the total cost of CHP use including capital costs, fuel costs, and utility tariffs. A method to accurately determine the potential savings that CHP systems can provide is developed as part of this research.; A fully integrated CHP system was designed, built and integrated into an existing fully-occupied commercial office building. Computational models were then developed and validated with experimental data to predict the performance of the CHP systems and to facilitate the optimization work. Traditional economic evaluations such as simple payback and life-cycle cost analysis techniques are useful to determine a general sense of feasibility, but they have limitations in terms of accuracy with respect to many economic and site-specific factors. Therefore, a comprehensive net cost function is developed to fully describe all economic parameters affecting the true cost of installation and operation of a CEP system in a commercial office building.; The optimization is performed on a system selection level, to establish the best suited system for a specific application, as well as an operational level, to establish an operational method that is based on input conditions at the facility. The optimization is evaluated based on economic considerations and uses data collected from the commercial office building as input parameters. The optimization uses two different techniques. A traditional optimization routine is developed where one CEP system is evaluated and systematically compared against other configurations until the system with the minimum net annual cost is found. Finally, a genetic algorithm is utilized which addresses the discontinuous nature of available CEP equipment capacities by employing evolutionary techniques to minimize the net cost function. The major innovative contribution of this research is the development of a tool that provides insights and guidelines that help system engineers, designers, and integrators to effectively choose, design and operate integrated systems for specific small-scale commercial applications.