Explanation:
Electrolysis is the process of conversion of electrical energy into chemical energy. In electrolysis, electrical energy is used to break stable chemical bonds. So energy is required to overcome the chemical forces and hence electrolysis is endothermic. Endothermic here implies that energy is required for the process to be carried out and the form of energy is electrical and not thermal.
-----
Answer: it requires electricity to sustain the reaction.
