Does economic growth stimulate energy consumption?New evidence from national and regional levels in China

A detailed investigation of the nexus between economic growth and energy use is imperative for formulating sustainable development policies.In this study,we examine panel cointegration and causality relations among economic growth,energy use,capital stock,and labor in 30 Chinese provinces between 2000-2019.We conduct a comprehensive empirical analysis based on panel modeling and a neoclassical production function.The findings of the second-generation panel unit root and co-integration tests reveal that these variables have long term co-integration linkages.We then perform a panel cointegration estimation using the fully modified ordinary least squares technique and find that total energy consumption,electricity consumption,capital stock,and labor significantly influence economic growth at the national and regional levels in China.Moreover,the outcomes of the Dumitrescu-Hurlin causality test indicate the existence of a two-way causal nexus between economic output and total energy consumption at the national level,but only a causal link from GDP to total energy use in the eastern and central regions.Conversely,a causality from total energy use to economic output is identified in the western region.Finally,we provide policy implications for the sustainable development of both energy and the economy at the national and regional levels.

Modeling and configuration optimization of the rooftop photovoltaic with electric-hydrogen-thermal hybrid storage system for zero-energy buildings:Consider a cumulative seasonal effect

Rooftop photovoltaic(PV)systems are represented as projected technology to achieve net-zero energy building(NEZB).In this research,a novel energy structure based on rooftop PV with electric-hydrogen-thermal hybrid energy storage is analyzed and optimized to provide electricity and heating load of residential buildings.First,the mathematical model,constraints,objective function,and evaluation indicators are given.Then,the simulation is conducted under the stand-alone condition.The annual return on investment and the levelized cost of energy of the system are 36.37%and 0.1016$/kWh,respectively.Residential building with the proposed system decreases annual carbon emission by 25.5 t.In the third part,simulation analysis under different grid-connected modes shows that building system will obtain better economics when connected to the grid,but the low-carbon performance will be reduced.Finally,the cumulative seasonal impact of the countywide rooftop PV buildings is discussed.The result indicates that the energy structure proposed in this paper can effectively reduce the grid-connected impact on the local grid.This model and optimization method developed in this paper is applicable to different climate zones and can provide management support to the investors of NZEB before the field test.

Economic analysis of hydrogen production from China’s province-level power grid considering carbon emissions

Hydrogen energy contributes to China’s carbon peaking and carbon neutralization by serving as an important energy carrier.However,the calculation of the cost of hydrogen production by the power grid ignores the current cost of carbon emissions.To measure the cost of hydrogen-production projects in various provinces more comprehensively and accurately,this study incorporates the carbon-emission cost into the traditional levelized cost of hydrogen model.An analysis of the energy structure of the power supply is conducted in each province of China to calculate carbon-emission costs,which are then subjected to a sensitivity test.Based on the results,the carbon-emission costs for hydrogen in each province are between 0.198 and 1.307 CNY/kg,and the levelized cost of hydrogen based on carbon-emission costs varies from 24.813 to 48.020 CNY/kg;in addition,carbon-emission costs range from 0.61%to 3.4%of the total costs.The results also show that the levelized cost of hydrogen considering carbon-emission costs in the Shanghai municipality specifically is most sensitive to the carbon-emission price,changing by 0.131 CNY/kg for every 10%fluctuation in the carbon-emission price.

Expanded models of the project portfolio selection problem with learning effect

This research develops two new models for project portfolio selection, in which the candidate projects are composed of multiple repetitive units. To reflect some real situations, the learning effect is considered in the project portfolio selection problem for the first time. The mathematical representations of the relationship between learning experience and investment cost are provided. One numerical example under different scenarios is demonstrated and the impact of considering learning effect is then discussed.