This study is based on understanding the applications and design of microgrids in different electricity markets. The main objective of this study is to identify and quantify the effect of critical decision variables on the system design aspect of microgrids. Various deployment models are examined in three different electricity markets - telecoms, single buildings and communities. The models for each market are developed based on the grid availability and quality of service, thus divided in three categories – off grid, grid intermittent and grid secure. Deployment models are varied utilizing centralized power generation, distributed power generation and storage technologies. The models developed are sub divided into different scenarios based on the extent of renewable energy penetration included in the system design. The study provides a comparison among these deployment scenarios and models providing critical reasoning for their validity. The models are developed using real time technical data and manufacturer data sheets for different technology types. The microgrid models and scenarios are developed using HOMER (Hybrid Optimization of Multiple Energy Resources), claimed as the world’s leading microgrid modeling software [1]. The technical and economic results generated from HOMER for the developed models are analyzed and discussed. As the models are developed for specific locations and specific load profiles, a sensitivity analysis is carried out for all the models to understand the system design variations for locations with different resource availability and different electricity prices. The results for this analysis are discussed in detail to understand the critical decision variables in system design for each market.