Dr. Ran Li

Talk Title:

Thermodynamic analysis of organic Rankine cycle off- design load performance under different user load demand patterns

Talk Abstract:

With the growth of global energy demand, renewable energy will be the main energy form in the future in order to achieve sustainable development. Currently, various renewable energy power generation technologies, including solar energy, geothermal energy and biomass energy, have become increasingly mature, while the establishment of renewable energy power generation network is not yet perfect. A complete power generation system mainly includes three parts: heat source supply, power cycle system and user load demand. Improving the flexibility of renewable energy power generation system and achieving the balance between supply and demand are important problems in the process of establishing renewable energy power generation network in the future. Additionally, the mutual influence among three parts will be the important reference factor to for macro-control of user’s electricity consumption mode and realization of energy conservation and emission reduction. For the heat source supply, geothermal and biomass energy can be used as stable input heat sources in the widely used renewable energy, as for solar energy, in recent years, with the development of energy storage technology, it can also be a stable heat source input into power cycle system. Therefore, when the heat source supply is stable, the flexibility of the whole power generation system is mainly reflected in the matching of the power cycle system and user load demand. So this paper mainly explores the influence law between user load demand and power cycle system. In the study, in order to distinguish different user load demand patterns, the daily load curves of user demand are classified according to different land types in the literature, and the user load demand patterns are mainly divided into three categories: industrial, commercial and residential areas by mathematical clustering analysis. For power cycle system, Organic Rankine Cycle(ORC), which has significant advantages in the utilization of medium and low temperature heat sources is chosen as the main power generation unit, and the heat source is geothermal water as a stable heat input. The overall power generation system is constructed in commercial software Aspen plus ® . Meanwhile, the performance of power cycle system is calculated by utilizing the optimization function of the software. According to the calculation, the performance characteristic of power cycle system under different user demand patterns is obtained, which provides reference for the setting of rated load of power plant. At the same time, it can be used to guide the macro-control of power grid to achieve higher energy utilization efficiency.

Keywords:

ORC, Off-design, Load pattern