Exploring policy space: Interactions between policy instruments on household energy efficiency. The case of domestic cold appliances in Germany

Household energy efficiency policy in Germany gets more and more differentiated since an increasing number of policy instruments targeting various fields of application are imple-mented and proposed by policymakers. Therefore, overlaps between such policy instruments become more likely. On the one hand, positive overlaps may allow realising synergies like an increased effectiveness or reduced costs stemming from a combination of policy instruments. However, the probability of negative overlaps and, thus, unintended outcomes like a lower effectiveness or additional costs related to a combination of policy instruments may grow on the other hand. This thesis considers selected policy instruments on domestic cold appliance energy efficiency that have been implemented in Germany. In a first step, the functioning of individual policy instruments is investigated. Based on that, interactions within combinations of the selected policy instruments are explored. This is done by reviewing relevant literature and policy evaluation studies, conducting expert interviews as well as applying a framework for forming views on interactions as suggested by Boonekamp (2005). The findings show that the EU energy label sets the framework for domestic cold appliance energy efficiency in Germany. Moreover, rebate programmes, information campaigns and minimum energy efficiency standards respective voluntary commitments are also found to be effective. Less successful policy instruments in improving domestic cold appliance energy effi-ciency are found to be cooperative procurement as a stand-alone instrument and a green tax. Furthermore, it is argued that most combinations of the investigated policy instruments have a reinforcing relationship. Based on the findings it is concluded that interactions between policy instruments on house-hold energy efficiency are still relatively unexplored. Further research in this area would facili-tate considering the issue of interactions between policy instruments in evaluation studies.