This paper presents a modular, dynamic and spatially distributed model of thermoelectric elements for marine applications intended to assess the low-grade waste heat recovery potential of thermoelectric devices on-board seagoing vessels. The model describes the dynamic behaviour of marine thermoelectric components and captures the detailed thermodynamic and thermoelectric process phenomena. Validation against experimental data from the literature indicates good model predictive ability. Two marine applications are examined using the model: (a) a scavenge air cooler, and (b) an auxiliary engine exhaust gas duct section integrated with thermoelectric generators. For each case, a parametric analysis is conducted to identify the designs that yield maximum thermoelectric efficiency and power output. The study concludes that thermoelectrics can recover low-grade waste heat on-board ships. Systems engineering modelling and simulation techniques can successfully determine the best system design, to achieve maximum energy harvesting, satisfying the weight, space and operational constraints on-board. (C) 2015 Elsevier Ltd. All rights reserved.