The Heating Operation Analysis Of A Cogeneration System Integrated Energy Storage System

Cogeneration is the ballast stone of China’s strategy to achieve "Peak Carbon Dioxide Emissions" and "Carbon Neutrality".With the full-scale coverage of centralized heating in China,the peak-to-valley mismatch between the heat supply of the CHPs（the Combined Heat and Power）and the residential heat load is increasingly prominent.The new heating technology of coupling energy storage system and cogeneration system can realize the "peak-valley shifting" of centralized heating and improve the adaptability of centralized heating and residential heat load without increasing the energy consumption of heat source.In the process of cogeneration coupled energy storage system,the problems that the auxiliary heat storage（AHS）system needs to absorb heat from the heat supply network in the redundant phase and release heat to the heat supply network in the undersupply phase,and the resulting changes in the operating conditions of the unit and the evaluation of the thermal economy of the new system will be generated.Therefore,it is important to determine the application conditions and application effects of the heat storage heating mode（HSHM）for the energy-saving operation of the new integrated system.An integrated heating system（IHS）that integrates a 600 W coal-fired CHP plant with its heating network of a sensible heat storage system based on Therminol VP-1 heat transfer oil by Ebsilon Professional was established in this paper.The accuracy and generalizability of IHS was checked,using the heat supply operation data of actual unit and the collected the heat load data and meteorological data in local.The peaking phenomenon between heat supply of IHS and residential heat load was found in the results of simulation operation.Therefore,the HSHM is proposed using the AHS for heating,while the original heating mode（OHM）without modifications and the additional coal-fired heating mode（ACHM）are also proposed and used to compare with the HS-HM on thermodynamic principles,and finally thermodynamic performance of the three modes is analyzed.The results show that the ACHM compared to HSHM and OHM,coal consumption rose by 12g/k Wh and 59.9t/h of new extracting steam was used to improve overall heating,while the average net heat output of HSHM decreased by only 2.5MW compared to OHM and the exergy efficiency of the heating process improved by 2.22%It shows that the HSHM is better than the conventional ACHM in terms of energy saving and effective energy utilization.New CHP thermal economy indexes based on nonlinear heat load weighting factors,"heat saturation" and "heating deviation",was proposed to improve the problem that traditional thermal economy indexes cannot accurately evaluate the thermal economy of HS-HM.The new indexes were used to evaluate the thermal economy of the above IHS.The results show that the heat saturation of both ACHM and HSHM reaches 100%,which improves the heat saturation of 88% in OHM,and ACHM improves the heating deviation by 1.05% compared with OHM,while HSHM reduces the heating deviation by 0.98% compared with OHM,which is in line with the simulation results.The new indexes were also used to evaluate the heat supply and load data involved in another literature,and the results show that the new indexes could also accurately improve the peaking phenomenon in the literature.It is shown that the results of the HSHM to improve the adaptability of centralized heating and residential heat load can be accurately quantified by the heat saturation and heating deviation.The above HSHM of IHS based on improved genetic algorithm optimization for heat supply in CHP was proposed to further improve the adaptability of centralized heating and residential heat load.Using heat saturation and heating deviation as the quantification basis of the fitness function in the improved genetic algorithm,the algorithm was used to search for the optimal solution of heat supply in HSHM.The results show that the reduction rates of heating deviation in HSHM are maintained above88% under several outdoor temperature operating conditions,and the heating deviation are below 0.6 after optimization,and the minimum indoor temperature are maintained in a stable range.It shows that the method can further improve the heating operation of HSHM.In summary,cogeneration after adopting the HSHM can effectively improve the comfort of residential heat users,reduce coal consumption,increase energy utilization efficiency,which achieves the purpose of energy saving and consumption reduction,providing a theoretical basis for the application of energy storage in CHPs.