Improved Ramping and Reserve Modeling of Combined Heat and Power in Integrated Energy Systems for Better Renewable Integration

With the largest installed capacity of wind power and solar PV in world, China is experiencing an approximately 10% curtailment major northern provinces. The combined heat (CHP) units account for over 50% local thermal generation capacity, hardly making contributions to ancillary services due complex coupling constraints, thus are barriers renewable energy integration. This paper explores opportunities increasing flexibility CHP by improving modeling ramping reserve constraints. Reformulated constraints proposed via analyzing internal mechanical structure introducing regulation exchange rate controlled heating butterfly valve. A reformulated available model put forward based on compensation mechanism between storages. models examined a 6-bus test system results show that constraint improves notably capability units, especially operating parallel with storages, facilitating integration during morning hours; whereas release hidden storages supply reserves, enabling additional energy.