•A comprehensive classification of work-heat integration problems is presented.•A superstructure is proposed to eliminate trivial and combinatorial solutions.•A novel simulation-based metaheuristic optimization approach is proposed for WHENS.•The methodology is more accurate and simpler than the previous approaches. Integrating work synergistically within heat exchange networks can offer considerable energy savings. Several publications have attempted to optimize this integration using a mathematical programming approach. However, the equation-based approach necessitates simplifications, and requires analytical correlations that often fail to reflect thermophysical properties accurately. In this article, the first simulation-based methodology is presented for work-integrated heat exchange network synthesis, which needs no correlations or simplifying assumptions. For this, a generalized superstructure is proposed, which not only accommodates the liquid and vapour-liquid phases, but also reduces the feasible search region for network synthesis. Particle swarm optimization has been used as the more suitable method for the proposed non-convex multi-modal simulation-based optimization problem. The methodology is illustrated using several scenarios of a literature case study on a liquid energy chain.