Electrochemical reduction of nitrate to nitrogen is an economical and environmentally friendly technology for sustainable nitrate removal. Herein, a kind of electric kettle equipped with an electrochemical system was proposed for nitrate reduction investigation. A copper-modified titanate cathode (Cal-Ti/Cu) was prepared via electrodeposition-calcination method, and used for the electrochemical nitrate reduction. The results show that the nitrate conversion rate of 65.37 % with a nitrogen selectivity of 60.61 % was obtained when the Cal-Ti/Cu was used as the cathode at 80 °C, with a reaction rate constant Kobs of 0.0187 min−1, which was 37.40- and 20.78-fold enhancements relative to that of the Ti and the Ti/Cu electrodes, respectively. Thermodynamic analysis indicated that temperature increasing can enhance the nitrate conversion rate and nitrogen selectivity. Particularly, the coexisting calcium ion can boost the efficiency of the total nitrogen removal rate, which was increased from 39.62 % to 74.2 % when the calcium ion concentration was up to 450 mg·L−1. When the electrochemical system was applied, only 0.027 % to 0.678 % increase in energy consumption relate to the water heating power of a common kettle, which can be easily accepted by the household. This work may provide a new approach to the quality improvement of household drinking water.