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The particular “rich coal, meager oil, and deficient gas” energy structure of China determines its high degree of dependence on coal resources. After over 100 years of high-intensity mining activities in Northeast China, East Region, and the Southern Region, coal mining in these areas is facing a series of serious problems, which force China’s energy exploitation map to be rewritten. New energy bases will move to the western and northern regions in the next few years. However, overlapping phenomena of multiple resources are frequently encountered. Previous exploitation mainly focused on coal mining, which destroys many mutualistic and accompanying resources, such as uranium, gas, and oil. Aiming at solving this unscientific development mode, this research presents a case study in the Ordos Basin, where uranium, coal, and gas/oil show a three-dimensional overlapping phenomenon along the vertical downward direction. The upper uranium and lower coal situation in this basin is remarkable; specifically, coal mining disturbs the overlaying aquifer, thus requiring the uranium to be leached first. The technical approach must be sufficiently reliable to avoid the leakage of radioactive elements in subsequent coal mining procedures. Hence, the unbalanced injection and extraction of uranium mining is used to completely eradicate the discharged emissions to the environment. The gas and oil are typically not extracted because of their deep occurrence strata and their overlapping phenomenon with coal seams. Use of the integrated coal and gas production method is recommended, and relevant fracturing methods to increase the gas migrating degree in the strata are also introduced. The results and recommendations in this study are applicable in some other areas with similarities.

A positive energy system that produces more renewable energy than its demand while ensuring appropriate comfort levels is an excellent path towards increasing the portion of renewable energy, reducing carbon emission, and increasing the energy system’s overall performance. In particular, it has been believed as step forward towards zero energy systems. Recent progress in positive energy building and community levels is gaining interest among different stakeholders. However, an inadequate understanding of the positive energy system is widely noticed in many projects, and a shortage of standard details on the positive energy system still prevails in the research community. Therefore, a state-of-the-art review of positive energy building and community is conducted in this paper. Firstly, this paper begins with the definitions and concepts of positive energy buildings and communities. Secondly, it comprehensively describes the energy supplies, demands, indicators, storage, energy management, roles of stakeholders, and bottlenecks of positive energy systems. Thirdly, the main differences between positive energy buildings and communities are summarized. Fourthly, the impact of smart energy grids and new energy vehicles on the positive energy buildings and communities is derived. As a conclusion, this paper shows that even though all the energy-efficient buildings such as passive buildings, nearly zero energy buildings, zero energy buildings, positive energy buildings look like an up-trending scale of renewable penetration, considerable differences are visible among all, and the same thing applies to the community level. Furthermore, considerable differences exist when comparing between positive buildings and communities regarding both the technical and economic perspectives.

In the ten years since committing to clean energy transition, China has formulated a large number of policies and programs to achieve some very ambitious targets. This paper argues that the dearth of empirical studies concerning the implementation of these new policies and programs has created a knowledge gap between official policy documents, which are vague and lacking in specifics, and official policy outcomes, which are unreliable. In particular, the merits and limitations of flexible implementation with regard to desirable outcomes need to be debated and clarified. This paper calls for more empirical investigation in four areas as a starting point: (1) the nature and extent of flexibility in the implementation; (2) implementation strategies and their impacts; (3) factors that shape the behavior of local officials responsible for implementation; and (4) the relationship between the central-local relation and policy implementation.

Accurate modeling and forecasting monthly electricity consumption are the keys to optimizing energy management and planning. This paper examines the seasonal characteristics of electricity consumption in Hong Kong—a subtropical city with 7 million people. Using the data from January 1970 to December 2014, two novel nonlinear seasonal models for electricity consumption in the residential and commercial sectors were obtained. The models show that the city’s monthly residential and commercial electricity consumption patterns have different seasonal variations. Specifically, monthly residential electricity consumption (mainly for appliances and cooling in summer) has a quadratic relationship with monthly mean air temperature, while monthly commercial electricity consumption has a linear relationship with monthly mean air temperature. The nonlinear seasonal models were used to predict residential and commercial electricity consumption for the period January 2015–December 2016. The correlations between the predicted and actual values were 0.976 for residential electricity consumption and 0.962 for commercial electricity consumption, respectively. The root mean square percentage errors for the predicted monthly residential and commercial electricity consumption were 7.0% and 6.5%, respectively. The new nonlinear seasonal models can be applied to other subtropical urban areas, and recommendations on the reduction of commercial electricity consumption are given.

Behavior-driven energy conservation has been a promising strategy for reducing building energy consumption as well as carbon emissions. With the intention of revealing the impacts of an individual’s personality basis on energy conservation behavioral attitudes and intentions in households and offices, the present study proposes and conducts an experiment in Xi’an, China with two groups for the investigation of such attitudes towards household energy-saving behavior (HESB) and office energy-saving behavior (OESB), respectively. The research adopts structural equation modeling for experiment data analysis. The analysis results suggest that the two personality traits, Agreeableness and Neuroticism, are significantly related to both HESB and OESB attitudes. Especially, agreeable people tend to present stronger energy-saving attitudes, while individuals with higher Neuroticism are less likely to do so. The results indicate that the impacts of these two traits on energy-saving attitude are found to be less influenced by different environment settings. Further, the results find that Extraversion positively influences energy-saving attitude in the office environment, while Openness only significantly works in the household environment. It is hoped that the findings of the present study can provide informative references to energy-saving intervention design as well as further studies on the spillover of pro-environmental behaviors.

Haze is a major environmental concern in many cities because it adversely affects people’s physiological and psychological well-being. This paper examines the extent of haze in Macao during the period 1986–2016. It identifies the relationships between haze, energy use, and meteorological conditions directly. The haze in Macao changed over the period 1986–2016 with air pollution getting worse and then improving after 2007. Specifically, the number of haze hours increased from 3 in 1986 to 766 in 2007, and then dropped to 57 in 2016, while the total energy use increased from 12,246 TJ in 1986 to 37,144 TJ in 2007, and then to 42,405 TJ in 2016. As per primary energy, Macao used 12,096 TJ in 1986, 21,388 TJ in 2007, and 16,647 TJ in 2016 excluding aviation kerosene. Bivariate correlations show that haze was most positively and significantly associated with annual primary energy use. Multiple regression analysis indicates that the number of hours with haze was significantly, positively related to the consumption of gas oil/diesel, fuel oil, and natural gas in Macao and aviation kerosene. Nevertheless, the improvement in Macao could come at a cost to areas in downwind of Zhuhai’s coal power stations supplying Macao’s electricity energy.

The economic structure of a city evolves as the city develops, resulting in a change in energy consumption. This paper presents a historical review of Hong Kong’s economic development and energy consumption from 1970 to 2015. Based on the official data from the Hong Kong government, it was found that Hong Kong’s gross domestic product increased from HKD 208 billion in 1970 to HKD 2398 billion in 2015 in which the contribution from the manufacturing sector peaked in 1985. Energy consumption increased by 9.3 times from 140.2 PJ in 1970 (mostly oil products) to 1298.2 PJ (including oil products, natural gas, coal, and imported electricity) in 2015. The greenhouse gas (GHG) emissions due to energy consumption were determined based on emission factors for different fuels. Results show that GHG emissions increased from 10.7 million tons (Mt) of CO2-equivalent in 1970 to 99.1 Mt of CO2-equivalent in 2015.