Polygeneration energy systems have drawn great attention because of their superiority over conventional stand-alone plants in energy efficiency and emissions control. Although many approaches have been made to the process design of polygeneration energy systems, most of them use coal gasification as the only gas source and produce only a single type of chemical product. In this paper, we present a dual-gas sourced process design which utilizes, besides synthetic gas (syngas) from coal gasification, coke oven gas as gas sources and co-produces methanol, dimethyl ether, and dimethyl carbonate via an integrated catalytic synthesis procedure. A process simulation based on detailed chemical kinetics is presented to illustrate its feasibility. Results of an exergoeconomic analysis are provided to indicate the exergy loss in each functional block within the process. Based on the analysis, an exergy cost distribution diagram is presented, showing the production cost of a product over each functional block. (C) 2011 Elsevier Ltd. All rights reserved.