In view of the shortage of fossil energy and the environmental pollution, the clean, low-carbon and renewable liquid biofuel offers as an important alternative of the fossil fuel. For the huge population and the limited cultivated land resources, it is necessary to develop non-grain energy crops on a marginal land to produce the liquid biofuel in China. The marginal land resources for three representative raw crops including the sweet sorghum, the cassava and the rape are estimated in this paper. The multi-factor analysis method and the dynamic threshold method are adopted to evaluate the marginal land resources. An optimized non-grain planting mode is to be adopted in order to provide an important support for planning the cultivation of the non-grain energy plants and the liquid biofuel industry. It is shown that the area of the marginal land resources suitable for the sweet sorghum, the cassava planting and the winter fallow fields suitable for the rape planting in China are about 34.69, 21.66, 19.95 million ha, respectively. The total area of the marginal land suitable for the development of the liquid biofuel is about 59.98 million ha.

In order to cope with the global climate change and the resource and environmental crisis, the energy structure in China should be adjusted and optimized, to gradually increase the proportion of the renewable energy development and utilization, and to solve the bottleneck problem of the renewable energy storage. In China, there are a large number of abandoned mines, which provide a large underground space to construct underground pumped storage power stations for the renewable energy storage. Based on two examples in Germany, this paper reviews related issues from the viewpoints of the rock mechanics, the mining planning, the mechanical settings, the energy system planning, the legal, environmental impacts, the economic applicability, the evaluation principles and other technical key points. The basic directions and the main contents of the related researches are discussed.

The calculation of the Greenhouse Gas (GHG) emissions is an important component in the sustainability certification of the energy product, but so far without an adequate methodology consistent with the certification requirements of the bioenergy sustainability in China. This paper presents the key elements involved in the GHG emission calculation for the bioenergy sustainable certification. Firstly, the general method of the GHG calculation is briefly presented. Then, based on the review of the methodologies of the bioenergy sustainability standards developed by the institutions in the world, the key elements of the calculation methodology are identified and analyzed. Finally, the paper analyzes different understandings in the current LCA analysis in China and makes preliminary suggestions on developing the GHG calculation methodology of the bioenergy for the sustainability certification in China.

Developing renewable energy is an important way to alleviate the energy crisis and the damage caused by climate change. However, the existing planning for renewable energy mostly focuses on a certain type of energy, without taking complementary advantages of multiple energy sources into consideration. The right thing to do is a coordinating and optimizing multiple energy planing. The Inner Mongolia Autonomous Region is rich in renewable energy and plays an important role in China's future renewable energy development map. This paper combines the spatial analysis technology and the multi-criteria analysis and evaluation methods to evaluate the potential resources of the bio-liquid fuel, the wind power and the solar power on the unused land of Inner Mongolia. And suggestions for the spatial layout of the coordinated development of three types of energies are made. It is shown that Alxa League has the potential for the development of three types resources at the same time due to its large area of unused land. For sweet sorghum fuel ethanol, in addition to Alxa League, Ordos also has a great development potential. For the wind power development, Bayannaoer and Wuhai cities can be given priority. For the development of the photovoltaic power generation, the focus should be put on Alxa League and Xilin Gol League.

The key of the sustainable development of human society is to realize the coordinated development among the energy system, the economic system and the environmental system. A quantitative analysis of their coordination is one of the core concerns in this field. With the rapid economic development, Ningbo becomes a new member of China's "trillion club". Taking Ningbo as an example, this paper establishes an index system of the energy-economy-environment (3E) system, analyzes the development level of the energy system, the economic system and the environment system in Ningbo and its counties, then calculates the coupling and coordination degree among the three systems with the algorithm for the coupling coordination degree. It is shown that the degree of the coupling and coordination of the three systems is increasing in the process of the economic development of Ningbo City, which is in a good and sustainable development state.

Food, energy and water (FEW) are the three essential pillars for human-being and society. Agricultural land is the largest ecosystem to provide food for human by consuming a large amount of energy and water. As population increases, there is an increasing pressure to address issues of the resource allocation and other conflicting objectives. Systematic thinking based on food-energy-water nexus (FEW-N) is necessary for the modeling and the optimization of the systems. However, challenges arise in making decisions among conflicting objectives, such as the profit, the food demand, the friendly environment, and the efficient use of water and energy. Despite the global studies of data, models and multi-objective optimization techniques, the holistic studies navigating the land use problems, exploring the trade-offs of land and the FEW resources are still few and far between, as well as the general and quantitative metrics for different solutions of the land use systems. Taking an experimental station in Shandong province as a FEW-N land use system, series of composite FEW-N metrics are developed to help solve the multiobjective optimization problem with systematic assessments. Computational results indicate that the trade-offs among diverse stakeholders can be achieved most effectively and consistently based on the composite FEW-N metrics. All objective-related solutions can be quantitatively evaluated by the proposed metrics, and the geometric metric GA can provide a visualization tool for comparisons of different solutions, to help the policy-makers to adjust policies across different stakeholders, production sectors, and technologies.

This paper studies the problems of the high energy consumption and the carbon emissions in the energy development, focusing on the coastal urban belt of Shandong Province, putting the factor of the carbon dioxide emission into the optimization of the energy consumption structure, and building a multi-objective optimization model of the energy consumption structure of the coastal urban belt of Shandong Province by using the method of the multi-objective planning, with the objective function as to minimize the cost of the carbon emission and the cost of the pollutant treatment from the energy consumption and with the constraint functions based on the economic development planning, the total energy consumption, the energy consumption structure and the carbon emissions. The results of the multi-objective optimization of the energy development in 2035 are as follows:the coal consumption accounts for 36% of the total energy consumption; the oil consumption accounts for 17% of the total energy consumption; the natural gas consumption accounts for 25% of the total energy consumption; and the clean energy accounts for 22% of the total energy consumption. All indicators are in line with the multiple objectives and the constraints of the energy consumption of Shandong Province. Finally, suggestions are made for the future development of the coastal cities and towns within the low carbon scenario:speeding up the structural reform of the energy supply side and the energy consumption side, and implementing effective measures such as clean energy and electricity substitution, in order to accelerate the transformation of the high-energy-consuming production mode, promoting the optimization and the upgrading of the economic structure, to achieve a sustainable development of the energy saving, the emission reduction and the low-carbon environmental protection.

With its large amount of the fossil energy consumption and the high carbon emission, the steel industry is an important partner in the construction of the carbon trading market. This paper analyzes the verification of the CO2 emission of the iron and steel plants in Liaoning province, and it is found that the main product of the crude steel is 54.6549~58.7637 Mt from 2013 to 2017; the total carbon emissions of the iron and steel plants in Liaoning province, included in the Carbon Emission Trading System (ETS), are 106.021~124.6814 Mt. The CO2 emissions intensity is in a decreasing tendency. From the perspective of the different sectors, the fossil fuel combustion CO2 emissions accounts for more than 80% of the total emission, followed by the emissions of net purchases of electricity and heat equivalent CO2, accounting for about 13%. From the perspective of the different processes, the iron making produces the most carbon emissions, with the average proportion of 40.82%, in a significant decrease trend. The carbon emissions of the other auxiliary parts increase significantly. The Pearson correlation analysis shows that the total CO2 emission, and the total energy consumption have a close linear correlation with the main products. Based on the carbon emissions of the iron and steel industry in 2017, it is found that the total quota of 15 iron and steel plants in Liaoning province will be 107.0051 Mt CO2, and the overall performance is quota surplus.

It is of great importance to study the carbon metabolism of the production-living-ecological space (PLES) for the integration of various elements and the structural adjustment in PLES. Taking Tangshan city as an example, this paper tracks and evaluates the carbon flow in the PLES from 2010 to 2015. It is indicated that the net carbon flow of the PLES in Tangshan is negative from 2010 to 2015, and the evolution of the PLES increases the carbon emission. The negative carbon flow is caused by the transformation from the Ecological Space to the Production Space while the positive carbon flow is due to the reverse transformation between the Ecological Space and the Production Space. In addition, the ecological relation of the carbon metabolism in Tangshan is mainly to limit the predatory relation, with the urban and the unutilized lands as the main part.

The active response to the climate change is one of the goals of sustainable development. This paper presents a temperature prediction model based on the graph attention mechanism. The attention mechanism on the topology of the temperature sites is used to selectively aggregate the temperature feature of the surrounding area. Then the neural network is used to fit the complex temperature change pattern and forecast the future temperatures. In the experiments, the temperature data of Beijing-Tianjin-Hebei region from 2000 to 2010 are used. A large number of experiments show that with this method more accurate predictions can be made with a small amount of historical temperature data. The model can provide the decision support for the climate prediction and the climate disaster prevention, with an important scientific and practical significance.

Drilling engineering plays an indispensable role in the modern energy exploration and development. The wellbore stability directly determines the success or the failure of the drilling operation. The traditional wellbore stability model does not allow any degree of wellbore damage, but in the actual drilling operation, the stable wellbore generally allows a limited width of caving area. The design based on the traditional wellbore stability model will lead to a high density of drilling fluid, which not only will increase the drilling cost but also will reduce the drilling efficiency, more likely will cause the loss of drilling fluid or even the formation fracture. According to the characteristics of the brittle shale formation, a wellbore stability model is established. Based on the logging data and the test data, a geomechanical model is established. The quantitative risk analysis method based on the limited collapse width is used to reasonably evaluate the wellbore stability probability and optimize the drilling fluid density. Based on the case study of a certain oilfield in Qinghai Province, this paper uses this method to optimize the density window of drilling fluid in the stable and unstable sections of the wellbore, to some extent, to improve the ROP and reduce the drilling cost. The probability of the wellbore stability can reach 91-98% according to calculation and evaluation. The calculation results are basically consistent with the actual situation, which shows that this method is effective and the results are reliable and practical.