Results

Many policy instruments evaluated in this study can achieve high savings at low or even negative costs for society. Economic instruments such as energy performance contracting and white certificates achieve diverging results as some of them are still rather new for the buildings sector, but have a high potential. Under the category of fiscal instruments, subsidies, grants and tax exemptions can lead to high saving, but subsidies are less cost-effective to society. Financial incentives can be helpful to kick-start the market for new energy efficient products as well as for developing countries where funding is often not. The effectiveness of voluntary instruments such as voluntary labelling and agreements depends on the context as well as on accompanying policy measures. Information instruments such as awareness raising programs are moderately effective depending on the design, but can successfully reinforce other instruments. Regulatory and control instruments such as building codes were revealed as the most effective and cost-effective category of instruments in this study if enforcement can be secured. A number of regulatory instruments achieved savings in the triple negative digit range of costs.

The highest GHG emission reductions in the sample were achieved by appliance standards, building codes, DSM programs, tax exemptions and labelling. Among the most cost-effective instruments were appliance standards, energy efficiency obligations, DSM programs, public benefit charges and labelling. Most of these are regulatory and control instruments. Appliance standards are projected to be especially cost-effective with net societal benefits of -65$/tCO2 in 2020 in the United States and -194$/tCO2 in 2020 in the EU.

These results can be explained by the special characteristics of the buildings sector which is very fragmented and characterized by many barriers to energy efficiency. Regulatory instruments proved to be the most effective as they can overcome some of the most important barriers, for example reduce the transaction costs since they eliminate the need to search for information or perform complicated calculations.

Since all instruments have advantages and disadvantages, appropriate combination with other policy instruments can maximize the overall effectiveness. The following policy instruments, for example, can be effectively combined:
-    standards, labelling and financial incentives
-    regulatory instruments and information programs
-  public leadership programs and energy performance contracting (EPC), i.e. EPC in the public sector
-    financial incentives and labelling.

However, these results, especially the conclusions for cost-effectiveness require further research as the amount of quantitative data was still limited in 2007, especially for developing countries, and partly difficult to compare due to missing information on baselines and methodologies of calculation. Evaluations are especially rare for developing countries. In addition, many policy measures are implemented as part of policy packages which makes assessment of single policy measures difficult.