Prior research suggests that set-based design representations can be useful for facilitating collaboration among engineers in a design project. However, existing set-based methods are limited in terms of how the sets are constructed and in their representational capability. The goal of this research is to demonstrate more general set-based design methods that are effective for characterizing and comparing competing technologies in a utility-based decision framework. To demonstrate the methods and compare their relative strengths and weaknesses, different technologies for a power plant condenser will be compared. The capabilities of different condenser technologies will be characterized in terms of sets defined over the space of common condenser attributes. It will be shown that designers can use the resulting sets to explore the space of possible condenser designs quickly and effectively. It is expected that this technique will be a useful tool for system designers to evaluate new technologies and compare them to existing ones. We compare four representational methods by measuring the solution accuracy (compared to another optimization procedures solution), computation time, and scalability (how results change with different data sizes). The results demonstrate that a support vector domain description-based method provides the best combination of these traits for this example.