•A novel application of electric spring (ES) presented – maintaining constant power through an impedance-varying load.•Two methods proposed – a linear approximation-based open-loop control and a PI-based closed loop control to test the constant power performance of ES.•The proposed approaches validated through simulation studies and experimental setup, close correlation observed.•Proposed techniques compared, advantages and disadvantages of both methods highlighted. Electric spring has recently been proposed as a special type of reactive power compensator to improve various attributes of the smart grid. Its extended functionality and applications are yet to be explored. This paper presents a new application of electric spring to ensure constant power across the loading elements under impedance variations. Two control methodologies are proposed to carry out this task: a linear approximation configuration and a closed-loop configuration. Design and mathematical analysis are provided, and the results of both control configurations are analyzed for a simulation model as well as a hardware setup. It has been found that experimental results are congruent with those obtained from the simulation model, hence ensuring the efficacy of theoretical framework.