DOD's Smart Power Infrastructure Demonstration for Energy Reliability and Security (SPIDERS microgrid program) prime integrator Burns & McDonnell has produced an outstanding white paper for anyone wanting to better understand the why's and how's of microgrids.
Overall it's a great paper, but two parts jumped out at me immediately for their value to decision makers. Here you go, the first is from a section on mission drivers:
By allowing multiple generation assets to provide power for a common load, microgrids greatly increase both the reliability of power and its efficiency of generation. Typically, the greatest beneficiaries of microgrids are customers with large, mission critical facilities or large power consumers in areas prone to frequent and/or prolonged outages (e.g. hurricane zones). Although facilities like these have utilized on site generation in the past, they are starting to migrate towards microgrids due to the many examples of single generators failing during prolonged outages thereby leaving the entire mission in jeopardy.