The ever increasing demand for energy has necessitated exploring innovative techniques for low and medium temperature energy extraction. Among them, Kalina cycle is considered efficient for extracting energy from low grade renewable sources like solar, geothermal and for waste heat recovery. In this work, we propose a Kalina cycle with turbine staging and heating between the stages. A case study is presented to illustrate the cycle. The cycle is analysed for varying pressure in the second separator and mass fraction of vapour from the first separator. The dependency of variables on separator temperature, vapour fraction at the turbine exit, net work output of the cycle, net heat input of the cycle and efficiency are analysed. Optimisation of efficiency with second separator pressure and mass fraction of vapour at the first separator as variables has been carried out using Genetic Algorithm. The optimised efficiency for the illustrative example shows an improvement of 4% compared to a simple Kalina cycle with same input parameters.