In this paper we present an application of the Energy and Climate Policy Interactions (ECPI) decision support tool for the qualitative ex-ante assessment of ten (10) combinations of energy and climate policy instruments addressing energy end users. This tool consists of four (4) methodological steps, where policymakers set preferences that determine the outcome of policy instruments interactions. Initially, interacting policy instruments are broken down in into their design characteristics, referring to parameters that describe functions of each instrument. Policymakers can express in a merit order the significance they attribute to these characteristics when designing a policy instrument. Evaluation criteria for assessing these instruments individually are used and policymakers can assign weights on them expressing their preferences. An overall assessment of combined policy instruments based on these steps have illustrated policy interactions added value per criterion and overall. The user of the tool takes useful insights as regards the most preferable combinations of policy instruments, the less preferable ones and those who are conflicting. (c) 2010 Elsevier Ltd. All rights reserved.