An increasing demand for sustainable gaseous fuels, such as biomethane and hydrogen, stimulated intensive efforts for developing new technologies and novel materials for gas separation and storage. Herein, a feasible strategy is developed for fabricating metalorganic frameworks (MOFs) nanofiber via combining electrospinning and in-situ growth method for high performance of biogas upgrading and storage. This approach rends the highly porous MOF materials highly distributed on the surface of the PAN nanfiber, which affords the resultant hierarchical porous structures without sacrificing their extraordinary properties such as ultra high surface area, thus contributing to the excellent gas storage capacities. The approach thus providing an promising strategy for structuring MOFs for gas storage applications.
This study established a heat-transfer model for pipeline networks, taking into account the attenuation and delay for district energy systems. The model can transform the hourly load of each building into the hourly output of the energy station to level the load. Furthermore, the hourly output of the energy station was calculated based on three scenarios that represented the locations of energy stations. The results indicated that there was a great difference between the superposition value of all the users and the output of the energy station.
This paper presents a social, economic and environmental study on a novel solar-powered zero-bill rural house space heating system compared to the conventional coal-powered and gas-powered systems. The system can significantly reduce the fossil fuel consumption, and reach to zero-bill operation, thus decreasing the operation charge and air pollution. By using the established model, the research analyses the energy performance of the novel zero-bill solar-powered system under a typical northern China weather condition (Taiyuan city). Then, it compares the economic and environmental performances between three space heating systems. It is found that, for a 100m2 typical rural house, the total heat demand is 8081kWh during the heating season. According to the local feed-in tariff, 0.75RMB/kWh , the PV model can earn 1297.2RMB per year, which is higher than the annual system electricity bill, 732.48RMB, and thus the novel system can reach to zero-bill and zero energy consumption. When it comes to economic analysis, due to the zero-bill and zero energy consumption characteristics, the system has a cost payback period of 14.8 years and a life-cycle net cost saving of 17573RMB compared with the coalpowered system. In contrast with the gas-powered system, the system has a cost payback period of around 5.9 years and a life-cycle net cost saving of 52723RMB. Furthermore, under the view of environment, one set system can annually save 1320kg standard coal or 1022.39m3 natural gas. Besides, it also annually reduces the 897.6kg harmful dust, 3220.8kg CO2, 99kg SO2 and 49.5kg NOx compared to the most environmentally contaminated coal-powered system. The widely use of the novel solar-powered system can enormously help to improve the living standard of the residents staying in a wide range of rural areas in northern China, and thus the system can harvest greater social, environmental and economic benefits subsequently.
This study researched an efficient-utilization planning method for community buildings, which considers supply- and demand-side factors comprehensively. The method consists of three key aspects. The first is the goal orientation of renewable energy utilization planning boundary condition optimization. The second is community building function optimization based on load leveling, and the third is building morphology optimization based on the energy control. The method is an important reference for community energy planning in China.
This study presents an experimental rig of singlestage heat transformer (SSHT), to compare its performances in case of producing high-temperature water (HTW) or low-pressure steam (LPS). SSHT was built with four vertical falling film heat exchangers using a LiBr-water binary working fluid and is driven by lowgrade hot water. Bilateral falling film vertical absorber is adopted for production of HTW or LPS. Following the principle of single variable, the effects of temperature and flowrate of heating water on the useful output heat, coefficient of performance (COP) and gross temperature lift (GTL) of the vertical SSHT were tested, respectively. The results show that bilateral falling film made it easier for the absorber to generate HTW and LPS directly. In case of producing water or steam, temperature at inlet and flowrate of heating water have similar effect on the useful output heat and COP. To some extent, we can improve the performance of SSHT by increasing the temperature.
The paper presents the gas permeability of marine sediments in the Shenhu Area of South China Sea. The sediments were obtained at the depth of 1600m below sea level. The solid density and volume weighted mean diameter of the sediments were 2.421 g/cm3 and 6.491 μm, respectively. The gas permeability of the marine sediments was measured by steady state method with confining pressures of 2MPa, 5MPa, 8MPa, 10MPa, 15MPa, 20MPa, 23MPa. The effective gas permeability of the sediments decreased from 2.638 × 10-16 m2 to 0.872 × 10-16 m2 as the confining pressure increased from 2 MPa to 23 MPa. The porosity of the sediments decreased from 41.82 % to 29.54 % as the confining pressure increased from 0 to 23 MPa. The gas permeability of the sediments was determined to be 1.535 × 10-16 m2 with confining pressure of 15 MPa and the porosity of 32.00 %. The longitudinal deformation of the sample was very sensitive to the confining pressure, and the compressibility of the sample in the radial direction was not obvious. The particle size term in the classical Kozeny-Carman equation was revised by a correction factor (N), and the experimental results fitted well with the curves when N value was 2.40. The reference group experiments indicated that the measurement results were reproducible.
Analysis of electricity consumption is important because it concerns the resilience of a country. Data mining techniques are needed that can handle fluctuations in these data, one of which uses SVR. The best parameter search for SVR is the most important for forming the model. In this paper, we will discuss in detail the combination of SARIMA-SVR and Firefly algorithms. The firefly algorithm is one of the metaheuristic techniques that provides accuracy which proven by the value of MAPE and RMSE.
Participation in demand response (DR) has been explored for many large energy using assets based on day-ahead markets. However, little is known about the use of multiple energy markets or DR for open canal systems. In this article, we propose the use of multiple flexible energy markets to enable DR for open canal systems in the Netherlands, where many large pumping stations are used for flood mitigation. We observed that the Dutch market is not yet rewarding DR, with relatively low-priced fixed-price contracts. However, when applied to the German market scenario, a cost saving of 13% was found. In conclusion, the method of combining two flexible energy markets seems successful. However, more simulations and research are needed to explore the full potential.
commitments vary considerably among countries. This study explores the cross-country difference in climate change policy stringency and its association with respective cultural differences. Particularly, we hypothesize that more religious countries incline to have lesser stringent climate change policies. Our empirical evidence using ordinary least square estimates provide support for this supposition. Estimates using instrumental variables and further evidence from individual-level analysis with a panel data of up-to 220758 observations over the past three decades confirm our main findings. The results hold up to a bunch of robustness checks. Our findings may be of relevance to policymakers looking to design climate change policy reforms.
The free-piston engine linear generator (FPELG) has the high thermal efficiency and simply structure. Thus, it is investigated by many researcher groups. However, many researchers main focused on the FPELG characteristics from the simulation results. Therefore, in the paper, the piston dynamics and the combustion characteristics of the gasoline FPELG from the experimental results were investigated. The experimental results demonstrated that the piston TDC is 32.2mm, the peak velocity is 5.3m/s and the frequency is 32.8Hz. And it is found that the optimal ignition timing of the free-piston engine is between 27.5 mm and 28 mm.