Energy storage devices are the lifeline of today’s society, and hence, researchers are trying to achieve 3Es (economical, environment friendly, and easy to prepare) along with other required technical data. Here, a new wheat starch + NaI system is synthesized which not only have good technical data such as high ionic conductivity (_˜3.61 × 10⁻² S/cm), very low dielectric relaxation time (_˜13.2 μs), and wide electrochemical stability window (_˜2.6 V) but it also satisfies 3Es conditions because it uses starch which is very cheap and abundant biopolymer available in large variety. The approximate cost of preparing 1 cm² of the sample is approximately INR 15. The prepared material is flexible, free standing film which can be easily stretched to 1.9 times to its length, and can be easily twisted up to 90°. The phase angle value approaches to −73° and maintains its value from 10 Hz to 9 kHz frequency range. The ESR value (of sample having thickness 0.48 mm and area 1.21 cm²) is very low (1.10 Ω). Parallel capacitance (C_p) to series capacitance (C_s) ratio is >0.9, and the value is maintained up to a wide frequency range (10 Hz to 10 kHz). Self-resonance frequency (the frequency limit below which energy can be stored efficiently) is also quite high (_˜0.1 MHz) for the present system. Hence, the studied system is a potential candidate for future electrochemical applications.