# Understanding Microgrid Sustainability: A Systemic and Comprehensive Review
## 8 Conclusions  
Microgrids are a promising technology for energy access, but their recurrent failures are still not fully understood by the scientific community. Energy microgrids and community microgrids have too often been studied separately, but for the understanding of these failures, the study of the system as a whole seems more relevant to detecting the problems. This article addresses this issue by proposing a new systemic overview of microgrids which unifies the representation of energy, information, financial, and social fields. Every field was described by elements, architectures, and issues. This novel unified field structure allows the study of the sustainability of microgrids through cross-comparison of issues.  
For the energy field, the main issue is its appropriate sizing with suitable quality components and appropriate system protection. This field has been extensively studied and appears to be relatively mature in its implementation within microgrids. Likely, advances in this area will mainly improve the technologies' overall efficiency or help reduce their economic and environmental costs.  
For the information field, the issues are driven by data, control, and communication considerations. This field poses many challenges for the future sustainability of microgrids. Energy management algorithms must be able to adapt to ever more complex microgrid architectures and ever higher efficiency demands. Furthermore, the issue of microgrid interoperability remains central, even if significant steps foreward have been made to find generalized and effective solutions for connecting several grids.  
The financial field has the issue of appropriate technico-economic design, financial management, and long-term planning for expansion and investment. This field should not be limited to a balanced cost/revenue balance; the financial field within microgrids is in charge of the connection between users and managers. For the long-term sustainability of the local electricity market, the business model must involve both the consumers and the energy market and find the balance between governance and overnership. Many new business models are emerging that consider the current local situation to provide the most appropriate solution from the most gathered to the most networked.  
The social field issues focus on acceptance, which is based on knowledge of the technology, understanding its usage rules, and building a positive perception of its usage. This area must remain central to the study of microgrids as it is the center of production, the end goal being to produce a quantity of energy that provides some work to a user. Acceptance of a microgrid is therefore major for its sustainability, allowing for ease of operation, utility support, and market participation. Real long-term studies should be encouraged to measure and better understand the impacts of this acceptance and to provide solutions that best improve the quality of life of users.  
Few articles in the literature attempt to link these different fields simultaneously. While this work presents an isolated, albeit unified, description of the fields, their causal links, events, and dependencies have yet to be precisely determined. These links should lead to systemic modeling of the microgrid along with its short, medium, and long-term dynamics. Based on this systemic vision, other future work should study microgrid sustainability, viability, scalability, and expansion.  
Conceptualization, A.B.; methodology, A.B.; validation, A.B., L.F.L.V. and C.F.; writing--original draft preparation, A.B.; writing--review and editing, A.B., L.F.L.V. and C.F.; visualization, A.B.; supervision, L.F.L.V. and C.F.; project administration, A.B., L.F.L.V. and C.F. All authors have read and agreed to the published version of the manuscript.  
This research received no external funding.  
Not applicable.  
The authors declare no conflict of interest.