Energy efficiency policy is expected to play a key role for meeting the European Union's energy targets (particularly for reduced energy demand and reduced CO₂ emissions) using a range of policy instrument combinations. However, most analyses undertaken so far have focused on single-policy measures rather than developing a more generic framework for assessing to what extent a particular policy mix is effective and under which specific conditions. This paper both contributes to the theoretical literature on policy mixes and undertakes an empirical analysis of the current policy mixes in buildings efficiency policy in 14 European Union countries. Building on the existing literature, and using expert knowledge, an assessment of the interaction of 55 pairs of policies is presented. This identifies policy mixes likely to deliver more, less or the same energy savings in combination than singly. The theoretical assessment is compared with actual policy mixes present within the European Union, highlighting that combinations of multiple financial incentives may need further investigation. By bringing these forms of knowledge together, the paper suggests how buildings policy mixes could be made more effective, shows gaps in current knowledge and highlights key research needs.

EU member states have been encouraged to introduce energy efficiency obligation schemes (EEOS) to help meet energy saving objectives. As a result, there are now 15 EU EEOS in existence, compared with just six prior to the introduction of the 2012 Energy Efficiency Directive. At the same time, the long-standing EEOS in Denmark and the UK have faced challenges because of concerns over increasing costs. This paper considers the role of EEOS in current and future EU and national policy. Firstly, this paper sets out in more detail the place of EEOS in EU energy policy. Then, the future of longer-established EEOS is explored, using Denmark and the UK as case studies. Recent and planned redesigns in these two countries are detailed, with analysis of the factors which led to changes in policy ambition. For new EEOS, key risks to delivery of savings are an over-ambitious delivery target and time line in the absence of policy learning opportunities. The policy risk for nine EEOS is assessed, with savings being most at risk in Croatia, Latvia and Spain. The paper concludes with an analysis of EEOS within the future policy mix. The discussion considers the place of EEOS in evolving EU policy, future savings from EEOS, their relationship with energy companies and the possible influence of different framings of energy efficiency. The continuing need for EEOS is explored, with concluding ideas about how to secure a strong and effective future for this policy tool.

This is an Author's Original Manuscript of an article whose final and definitive form, the Version of Record, has been published in Climate Policy 2010 copyright Taylor & Francis, available online at: http://www.tandfonline.com/10.3763/cpol.2010.064

Low carbon housing retrofit is often understood as a one-off, whole-house activity. However, an alternative model of low carbon retrofit is presented whereby improvements happen step by step over several years. This staged approach is described and contrasted with the one-off approach, and empirical evidence on both models is presented. Three key questions are considered: whether an over-time low carbon retrofit could be attractive for owner-occupiers; whether it could deliver sufficient carbon and energy savings; and what policy support would be needed. The benefits of over-time low carbon retrofit are explored through householder survey and qualitative data, as well as the time scales that apply to housing, renovation and homeowners. Technical issues around energy savings are explored, and the risks of ‘lock out’ investigated. Policy support measures specifically for over-time low carbon retrofit are suggested, with reference to existing policy approaches in the United Kingdom and European Union. Over-time low carbon retrofit could be attractive to (some) householders – at least 60% carbon savings could be achieved – and policy could be designed to recognize and support this form of low carbon retrofit. This approach provides an additional route to the uptake of energy-efficiency and renewable-energy measures. La rénovation des logements à faibles émissions de carbone est souvent comprise comme une activité s'opérant en une seule fois sur l'ensemble d'une maison. Il est cependant présenté un modèle alternatif de rénovation bas carbone selon lequel les améliorations interviennent étape par étape sur plusieurs années. Cette approche par étapes est décrite et mise en opposition avec l'approche en une seule fois, et des données probantes empiriques sur ces deux modèles sont présentées. Trois questions clés sont envisagées: une rénovation bas carbone étalée dans le temps peut-elle apparaître intéressante pour les propriétaires occupants? Cette approche permet-elle d'assurer suffisamment d'économies d'énergie et de carbone? Et quel soutien devrait être apporté par les politiques publiques? Les avantages d'une rénovation bas carbone étalée dans le temps sont examinés au moyen d'une enquête réalisée auprès des occupants et de données qualitatives, ainsi que des échelles de temps qui s'appliquent aux logements, à la remise à neuf et aux propriétaires. Les questions techniques relatives aux économies d'énergie sont étudiées, et les risques de «verrouillage technologique» sont examinés. Des mesures politiques de soutien spécifiquement destinées à une rénovation bas carbone étalée dans le temps sont suggérées, en faisant référence aux approches politiques existant au Royaume-Uni et dans l'Union européenne. Au fil du temps, une rénovation bas carbone pourrait être intéressante pour (certains) occupants – il pourrait être réalisé au moins 60 % d'économies de carbone – et les mesures politiques pourraient viser à reconnaître et soutenir cette forme de rénovation bas carbone. Cette approche fournit une voie supplémentaire pour l'adoption de mesures en faveur de l'efficacité énergétique et des énergies renouvelables. Mots clés: énergie, logement, bas carbone, politique publique, réhabilitation, remise à neuf, rénovation, temps