Improve the flexibility provided by combined heat and power plants (CHPs) – a review of potential technologies

Abstract

The rapid growth of intermittent renewable energy for electricity production brings a huge challenge to keep the balance between supply and demand in power systems, which further raises the need of flexibility. It has been well recognized that combined heat and power plants (CHPs) can play an important role in the provision of flexibility, due to their ability to switch the production between electricity and heat. However, there still lacks a comprehensive review about the flexibility provided by individual technologies involved in CHPs, which hinders the exploration of the capability of CHPs. In addition, new technologies and technology couplings have been proposed and adopted to further improve the flexibility in CHPs. This review aims to characterize the flexibility features of technologies that have been adopted or can be adopted by CHPs. Ramp rate, operation range, and power capacity are selected as key performance indicators for assessing technologies for providing flexibility services. Based on the collected result, suggestions are provided regarding the selection of technologies to enhance the flexibility provided by CHPs.