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Abstract The central role of occupants for achieving energy savings in residential buildings is increasingly recognised. Simulation programmes able to take into account occupant behaviour are considered to be powerful tools for bridging the gap between the predicted and the actual energy consumption for new buildings. Nevertheless, the majority of residential buildings that will constitute the housing stock in 2050 have already been built today, therefore occupant behaviour and building simulation tools need to be fully exploited for supporting the renovation of existing housing stock. The aim of this paper is to explore the role of occupant behaviour modelling in supporting decision-makers dealing with the design of renovation strategies for residential buildings. An Italian multi-family public housing building is assumed as case study to estimate the influence of three dimensions linked with occupant behaviour – management of the thermostat, management of the heating system, variation of building characteristics – on energy heating consumption. The results show that, while the occupant behaviour influences the heating loads up to 1/3 in case of high level of building retrofit, the less the building is renovated, the higher is the behavioural impact in absolute terms of energy reduction. Therefore, in order to be effective, renovation strategies are required to design appropriate informative instruments at an early stage to support behaviour changes towards responsible energy consumption.

Abstract The central role of occupants for achieving energy savings in residential buildings is increasingly recognised. Simulation programmes able to take into account occupant behaviour are considered to be powerful tools for bridging the gap between the predicted and the actual energy consumption for new buildings. Nevertheless, the majority of residential buildings that will constitute the housing stock in 2050 have already been built today, therefore occupant behaviour and building simulation tools need to be fully exploited for supporting the renovation of existing housing stock. The aim of this paper is to explore the role of occupant behaviour modelling in supporting decision-makers dealing with the design of renovation strategies for residential buildings. An Italian multi-family public housing building is assumed as case study to estimate the influence of three dimensions linked with occupant behaviour – management of the thermostat, management of the heating system, variation of building characteristics – on energy heating consumption. The results show that, while the occupant behaviour influences the heating loads up to 1/3 in case of high level of building retrofit, the less the building is renovated, the higher is the behavioural impact in absolute terms of energy reduction. Therefore, in order to be effective, renovation strategies are required to design appropriate informative instruments at an early stage to support behaviour changes towards responsible energy consumption.

Abstract Natural gas vehicles offer the benefits of reducing oil use, CO2 emissions and air pollutants. Promoting the use of natural gas vehicles is considered as one of the most important strategies towards sustainable transportation. China made remarkable progress in promoting natural gas vehicles over recent years, and its 4.6 million natural gas vehicles in 2014 represented the world׳s largest natural gas vehicle fleet. In this paper, the development of natural gas vehicles in China is reviewed based on a triple-perspective (Fuel-Vehicle-Infrastructure) technical–economical framework. The review indicates that (a) pricing of vehicle-use Compressed Natural Gas (CNG) and Liquefied Natural Gas (LNG) is essential in determining natural gas vehicle development. A pricing principle similar to the fixed CNG/gasoline price ratio (0.75:1) should be applied to LNG/diesel price ratio; (b) for CNG passenger vehicles, the modified CNG vehicles, with ¥3000–5000 additional cost, is more attractive to consumers than originally manufactured CNG vehicles, with about ¥10,000 additional cost. Vehicle retrofit should be permitted by the government with the precondition that retrofit standards are strictly enforced; (c) for CNG/LNG transit buses, the deployment is strongly affected by local government׳s preference. In regions with sufficient natural gas supply, the government should prioritize the deployment of CNG/LNG transit buses rather than other technologies; (d) for LNG commercial vehicles, with ¥60,000–80,000 higher cost than their counterpart diesel vehicles, financial incentive is critical for their development. China׳s current vehicle subsidy scheme should be extended to cover LNG commercial vehicles; (e) regarding refueling infrastructures, interference with urban land-use planning and long-time administrative approval are the major barriers. Local governments should launch dedicated plans and strategies to support the further deployment of CNG/LNG refueling infrastructures.

Abstract Natural gas vehicles offer the benefits of reducing oil use, CO2 emissions and air pollutants. Promoting the use of natural gas vehicles is considered as one of the most important strategies towards sustainable transportation. China made remarkable progress in promoting natural gas vehicles over recent years, and its 4.6 million natural gas vehicles in 2014 represented the world׳s largest natural gas vehicle fleet. In this paper, the development of natural gas vehicles in China is reviewed based on a triple-perspective (Fuel-Vehicle-Infrastructure) technical–economical framework. The review indicates that (a) pricing of vehicle-use Compressed Natural Gas (CNG) and Liquefied Natural Gas (LNG) is essential in determining natural gas vehicle development. A pricing principle similar to the fixed CNG/gasoline price ratio (0.75:1) should be applied to LNG/diesel price ratio; (b) for CNG passenger vehicles, the modified CNG vehicles, with ¥3000–5000 additional cost, is more attractive to consumers than originally manufactured CNG vehicles, with about ¥10,000 additional cost. Vehicle retrofit should be permitted by the government with the precondition that retrofit standards are strictly enforced; (c) for CNG/LNG transit buses, the deployment is strongly affected by local government׳s preference. In regions with sufficient natural gas supply, the government should prioritize the deployment of CNG/LNG transit buses rather than other technologies; (d) for LNG commercial vehicles, with ¥60,000–80,000 higher cost than their counterpart diesel vehicles, financial incentive is critical for their development. China׳s current vehicle subsidy scheme should be extended to cover LNG commercial vehicles; (e) regarding refueling infrastructures, interference with urban land-use planning and long-time administrative approval are the major barriers. Local governments should launch dedicated plans and strategies to support the further deployment of CNG/LNG refueling infrastructures.

Abstract Rapid economic growth and accelerating urbanization in the past three decades have accelerated the exhaustion of China’s mineral resources. China is the world’s largest consumer and importer of nickel resources; therefore, a growing domestic demand will increase China’s import dependence and in turn make it potentially vulnerable to supply shortages. One hundred years from 1950 to 2050 were examined for China’s nickel utilization. Identified domestic nickel resources can only sustain China’s industries until 2017, but nickel will reach peak utilization around the year of 2020–2022. Given the 5% annual increase in applications and the growing importation of minerals in China, the carrying duration of nickel resources until 2020 will require a nickel-recycling rate of more than 90%. To sustain China’s nickel utilization, future strategies should foster three solutions: maintaining a high level of imports, adjusting the landscape of nickel applications, and shifting from virgin mining of geological minerals to urban mining of anthropogenic resources.

Abstract Rapid economic growth and accelerating urbanization in the past three decades have accelerated the exhaustion of China’s mineral resources. China is the world’s largest consumer and importer of nickel resources; therefore, a growing domestic demand will increase China’s import dependence and in turn make it potentially vulnerable to supply shortages. One hundred years from 1950 to 2050 were examined for China’s nickel utilization. Identified domestic nickel resources can only sustain China’s industries until 2017, but nickel will reach peak utilization around the year of 2020–2022. Given the 5% annual increase in applications and the growing importation of minerals in China, the carrying duration of nickel resources until 2020 will require a nickel-recycling rate of more than 90%. To sustain China’s nickel utilization, future strategies should foster three solutions: maintaining a high level of imports, adjusting the landscape of nickel applications, and shifting from virgin mining of geological minerals to urban mining of anthropogenic resources.

This is the companion paper of part I of DeST overview. DeST was developed as a building simulation tool with the aim of benefiting both design of and research on building energy efficiency. During its development, DeST has been applied to many projects, development of building regulations, and research. This paper gives examples of several areas in which DeST has been applied, including building design consultation, building commissioning, building energy conservation assessment, a building energy labeling system, and scientific research. Examples from a demonstration building are presented to demonstrate the entire process of aiding design with DeST. Additional projects and regulations are also mentioned to introduce other applications of DeST.

This is the companion paper of part I of DeST overview. DeST was developed as a building simulation tool with the aim of benefiting both design of and research on building energy efficiency. During its development, DeST has been applied to many projects, development of building regulations, and research. This paper gives examples of several areas in which DeST has been applied, including building design consultation, building commissioning, building energy conservation assessment, a building energy labeling system, and scientific research. Examples from a demonstration building are presented to demonstrate the entire process of aiding design with DeST. Additional projects and regulations are also mentioned to introduce other applications of DeST.

Building occupancy is an important basic factor in building energy simulation but it is hard to represent due to its temporal and spatial stochastic nature. This paper presents a novel approach for building occupancy simulation based on the Markov chain. In this study, occupancy is handled as the straightforward result of occupant movement processes which occur among the spaces inside and outside a building. By using the Markov chain method to simulate this stochastic movement process, the model can generate the location for each occupant and the zone-level occupancy for the whole building. There is no explicit or implicit constraint to the number of occupants and the number of zones in the model while maintaining a simple and clear set of input parameters. From the case study of an office building, it can be seen that the model can produce realistic occupancy variations in the office building for a typical workday with key statistical properties of occupancy such as the time of morning arrival and night departure, lunch time, periods of intermediate walking-around, etc. Due to simplicity, accuracy and unrestraint, this model is sufficient and practical to simulate occupancy for building energy simulations and stochastic analysis of building heating, ventilation, and air conditioning (HVAC) systems.