In response to climate change, governments are developing policies to move toward ultra-low-energy or ‘zero-energy’ buildings (ZEBs). Policies, codes, and governance structures vary among regions, and there is no universally accepted definition of a ZEB. These variables make it difficult, for countries such as China that wish to set similar goals, to determine an optimum approach. This paper reviews ZEBs policies, programmes, and governance approaches in two jurisdictions that are leading ZEBs development: Denmark and the state of California in the United States. Different modes of governance (hierarchy: principal–agent relations, market: self organizing and network: independent actors) are examined specifically in relation to policy instruments (prescriptive, performance or outcome-based). The analysis highlights differences in institutional conditions and examines available data on energy performance resulting from a building policy framework. The purpose is to identify ZEBs governance and implementation deficits in China and analyse alternative governance approaches that could be employed in China, which is currently developing ZEBs targets and policies. Conclusions suggest that the ZEBs governance structure in China could benefit from widened participation by all societal actors involved in achieving ZEBs targets. China's ZEBs policies would benefit from employing a more balanced hybrid governance approach.

As the temperature in the summer period in Norway has been always moderate, little study on the indoor comfort of typical Norwegian residential buildings in summer seasons can be found. Heat waves have attacked Norway in recent years, including in 2018 and 2019. Zero energy buildings, even neighborhoods, have been a hot research topic in Norway. There is overheating risk in typical Norwegian residential buildings without cooling devices installed under these uncommon weather conditions, like the hot summers in 2018 and 2019. Three weather scenarios consisting of present-day weather data, 2050 weather data, and 2080 weather data are investigated in this study. The overheating risk of a typical Norwegian residential building is evaluated under these three weather scenarios. 72 scenarios are simulated in this study, including different orientations, window-to-wall ratios, and infiltration rates. Two different overheating evaluation criteria and guidelines, the Passive House Planning Package (PHPP) and the CIBSE TM 59, are compared in this study.

In this paper, a saving to investment ratio (SIR) method was used to determine the key prescriptive parameters for upgrading the building energy code with different energy reduction ratio requirements, including the U value of walls, roofs and windows; as well as a consideration of the efficiency of boilers and coefficient of performance of water chillers. An economic model for single typical energy saving technologies was established and the relationship between the incremental cost and the payback period of the different technologies was analysed; then the baseline building model was optimized by these measures in descending order according to the SIR methodology. The model method (SIR) was then applied to case studies in four climate regions of China. A large office reference building situated in Harbin, Beijing, Shanghai and Guangzhou in climate zones from north to south of China was analysed as examples to showcase the relationship between the building energy saving ratio and the incremental cost. The key prescriptive parameter requirements of walls, roofs, windows, chillers and boilers with 5% and 10% energy saving ratios were defined separately for these buildings.

Building energy conservation has gained tremendous interest since the 1970s energy crisis. Building energy standards have been established as prescribed guidelines for energy savings in buildings worldwide, among which those from China and the United States of America (USA) are representative of their advanced concept, comprehensive content and prospective guidance. This paper collected and generalized the main building energy standards in China (GB50189, JGJ26, JGJ134 and JGJ75) and the USA (ASHRAE 90.1), in terms of updating history, current status, energy saving potential and future development directions. Furthermore, a qualitative and quantitative comparison of the selected standards was performed. The results show that China has a more intact and comprehensive building energy standard system, better implementation, higher improvement in energy saving rates, and a more perspicacious upgrade towards zero-energy target, which results in effective energy savings in buildings. The ASHRAE standards have more fixed chapter framework, integrity and independence between versions, more detailed classification of building envelope and HVAC systems but less effective energy-saving effect and relatively poor implementation. The actual efficiency of standards in building energy saving is synthetically determined by the standard content, efficient implementation and explicit guidelines for future development, which is achieved through four main procedures. Based on the results, recommendations have been proposed for the future development of building energy standards with the ultimate goal toward zero energy buildings.