In this study, the economic and environmental benefits of stand-alone and grid integration are thoroughly analyzed with different system configurations of a PV/Wind/Diesel/Battery based hybrid energy system (HES) for five different climatic regions using hybrid optimization model for electric renewables (HOMER). A detailed techno-economic study of optimized hybrid systems is further examined by integrating the grid-connected option. The environmental benefits of HESs are discussed. The sensitivity of various sell-back price to the national grid is also investigated. Additionally, the barriers and opportunities of installing such projects in the off-grid regions are discussed. Results indicate that the cost of energy (COE, $/kWh) and the net present cost (NPC, $)ofthestand-alonehybridPV/Diesel/BatteryfortheRajshahiregionareslightlylowercomparedtootherareas,consideringthecostandenvironmentalemissions.ThesamesysteminChattogramshowsgreatpotentialbothfinanciallyandenvironmentally,overtheotherclimaticzones.Thegrid-connectedHESwiththesell-backoptionofferssignificantcost-benefits(0.07$/kWh), even over the grid tariff (0.10$/kWh). Similar revenues can be attained with the grid-connected PV/Battery-based system as substantial amount of excess energy could be supplied to the grid facilities. In the grid integrated HES, around 45,582 kg-CO2/yr could be saved compared to grid only system, whereas this amount is 32,905 kg-CO2/yr over the stand-alone hybrid PV/Diesel/Battery one.