## 5 Conclusions and Future Works  
This paper proposes a model for the optimal operation of the multi-energy microgrid for buildings integrated with PV considering an integrated demand response and heterogeneous energy storage. In the developed optimization framework, PV power was considered uncertain and the p-efficient point method based on historical data was applied to handle the stochastic PV within the MEMG system. Integrated demand response was presented and formulated as a linear model based on the quantized flexibility interval of the system load demand. In addition, the effect of HES on the operational problem was taken into account. The main goal of the proposed model is to minimize the cost associated with energy consumption and IDR implementation through deploying the full potential of the cooperation of IDR, energy converters and HES, considering operational constraints. Extensive case studies are presented to validate the effectiveness of the proposed model and illustrate the benefits of the cooperation of IDR with respect to PV power accommodation, raising energy efficiency and reducing the energy consumption cost of the system. According to the obtained results, the proposed operation strategy can help the system operator to reduce the total energy costs by 5.44% on a typical summer day and 3.5% on a typical winter day through implementing IDR as well as utilizing energy conversion facilities and HES systems. It can also be seen that the proposed method is an effective way towards achieving 100% accommodation of uncertain PV power in MEMGs.  
Noting that the proposed optimization model is established based on a steady-state analysis of the MEMG system, although it is valid and feasible for the daily scheduling and hourly operation of the MEMG system, the model is too rough to analyze the operation of MEMGs on a short-term time scale (minutes or tens of minutes), especially the model considering demand response. It is necessary to investigate the difference of response characteristics and dynamic change processes of different energies in response to short-term scheduling requirements at different time scales.  
As for future works, there are several directions that can be further extended: (i) multi-time scale optimization strategy for MEMGs considering the difference of response characteristics and dynamic change processes of heterogeneous energy will be explored; (ii) the participation degree model for energy consumers to participate in integrated demand response will be investigated, and in this stage, the impact of electricity and natural gas prices will be taken into account; and (iii) the detailed models for user-oriented and comfort-constrained IDR will be developed and incorporated in the optimal operation of multi-energy microgrids.  
[PERSON]: conceptualization, methodology, software, data analysis and writing of the original draft; [PERSON]-[PERSON]: conceptualization and checking of the overall logic of this work; [PERSON] and [PERSON] thoroughly revised the paper. All authors have read and agreed to the published version of the manuscript.  
This research was funded by the National Natural Science Foundation of China (NSFC), grant number 51777116.  
Not applicable.  
Data Availability Statement:Data sharing is not applicable to this article.  
The authors declare no conflict of interest.