Boilers using different fuels like HSD, LDO, coal, PNG and propane were taken into consideration in this study. Different parameters associated with boilers like economic factor, efficiency factor and the environmental impact factor were being calculated by taking measurements and collecting data from different plants in Odisha with variety of fuels. It is found that the most economical fuel is coal with a price index of 4.69 Rs/megacalorie and the most expensive fuel is LDO with a price index of 9.83 Rs/megacalorie. The most efficient boilers are propane‐fired boilers with an efficiency of 95.1% and least efficient boilers are coal‐fired boilers with an efficiency of 88.8%. PNG‐fired boilers had the lowest environmental impact around 1.0 and coal‐fired boilers had the highest around 6.0. A new concept of EEE impact index has been introduced which denotes the combined impact of Economic factor, Efficiency and Environmental factor. PNG was found to be the best fuel, having an EEE impact factor of 0.06 and LDO is the worst, having an EEE impact factor of 0.43. A case study was also carried out to convert a boiler from HSD‐fired to PNG‐fired, which was found to be very encouraging with a payback period of approximately 1 year. The IRR also calculated, it was around 120% making it very appealing to invest for a good financial gain. This can be used as a reference and guiding document for the industries to take decisions for fuel switching and achieve better sustainability by implementing this initiative.