This report discusses about an innovative way of generating additional power from any combustible fuel. The plant proposed for additional power generation is titled PHE plant, where PHE stands for "Power from Hidden Energy". It is so named as the plant can tap out additional energy from the transitional phase that exists during the transfer of heat energy from gaseous combustion product to any system in contact. From a given mass of gaseous combustion product at high temperature but at atmospheric pressure, we generally tap out only the heat energy stored But the said gaseous mass is having the potential for one another source of energy also, which is not properly availed in conventional plants. The proposed system is an answer to this. While tapping out heat energy from given mass of gas enclosed in a closed vessel that is at high temperature and at atmospheric pressure, there will be a pressure drop inside the vessel as per Gay lusac law. This pressure drop with respect to the surrounding will be a source for power in addition to the heat energy that is tapped out in conventional plants.