Co-optimization of configuration and operation for distributed multi-energy system considering different optimization objectives and operation strategies

•A sustainable DMES energy supply system for cities in cold regions is constructed.•A multi-objective co-optimization framework for design and operation is proposed.•An improved NSGA-II by MRM is Proposed.•Renewable energy capacity is equal for various strategies or optimization objectives.•Without WTGS, EXE and AC decreased 29.77% and 17.49%, PE increased 34.92%.