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Building materials have played a more and more important role in saving building energy since the central government of China set higher standards and requirements for new-constructed and retrofit buildings after 2005. Glazing units, especially energy-saving units including LOW-E coated glazing units and PVB laminated glass, are utilized nation-wide. This paper employs energy simulation to analyze the energy-saving effects of different glazing units in residential buildings in the city of Guangzhou, as an example of hot-humid climate in China. It appeals that the PVB laminated glass can refuse 44 % solar radiation to enter rooms and reduce 40 % of the shading coefficient comparing to clear glass. Meanwhile, in the aspects of operation and design of the HVAC system, 28 % of cooling load, 21 % of installed capacity and 8.6 % of full-load operation time can be saved.

With the development of SoC technology in recent years, the ultra-low power WiFi System on SoC Chip has emerged. As a result, WiFi-based Wireless Sensor Networks come into use, especially used in Automatic Meter Reading. While because the nodes of Wireless Sensor Networks have limited energy supply, smaller storage capability and slower calculation ability, the current WiFi technology cannot be directly applied to WiFi-based Wireless Sensor Networks. The protocols should be upgraded and the security algorithms should be improved to meet the new requests. Firstly, this article describes the network architecture of WiFi-based WSN for AMR system and discusses the reason for using this analogous Mesh architecture. Secondly, the new Hardware architecture of WiFi-based WSN node is designed to realize the AMR system and verify the research work. The node can collect the data of power meter by WiFi and can be powered by a Lithium Battery. Thirdly, on the basis of study work of WiFi original routing protocol HWMP, a new method on improving the energy saving ability of HWMP to adapt the new features of WiFi-based WSN is proposed. And the simulation work on the new routing protocol E-HWMP has been done with NS2 and the simulation results show that the life cycle of the network has been extended to some degree.

With the introduction of distributed generators (DG), the traditional distribution system characterized by radical network becomes a multi-source one. Therefore the accuracy of the equivalent model of distributed generators directly affects the precision of fault location. To solve this problem, this paper proposed a fault location method based on complex correlation Thevenin equivalent and strong tracking filter (STF) in distribution network with DG. Strong tracking filter (STF) can be used for real-time extraction of fundamental wave phase and amplitude of single phase voltage and current, and fast track the power parameters mutation. The method of complex correlation Thevenin equivalent takes into account the randomness of measurement data, DG impedance and load to overcome measurement error caused by the uncertainty of the data, so that the construction of the DG impedance model is more accurate. Simulation results show that the method of fault location proposed in this paper has advantages of high accuracy and strong robustness.

Stopping and accelerating at traffic lights is one of the main contributing factors to vehicular emissions in urban environments. The work in this paper demonstrates a generic guideline for minimizing CO2 emissions at traffic lights. This was done using an adaptive control, which uses a cost function for optimization, rather than network-specific control parameters. A new version of the emission model PHEMlight was used, which added of a fuel cut-off mode during coasting and other improvements compared to the previous version. Using this model, it could be determined that the emission optimal ratio between delay time and stops for the cost function of an adaptive control should be 1:4.8. Using this ratio a reduction of 7.6 % of CO2 emissions was achieved compared to a vehicle actuated control.

Most design optimisation studies for district heating systems have focused on the optimal sizing of network assets and on the location of production units. However, the strategic value of the flexibility in phasing of the inherently modular heat networks, which is an important aspect in many feasibility studies for district heating schemes in the UK, is almost always neglected in the scientific literature. This paper considers the sequential problem faced by a decision-maker in the phasing of long-term investments into district heating networks and their expansions. The problem is formulated as a multi-stage stochastic programme to determine the annual capital expenditure that maximises the expected net present value of the project. The optimisation approach is illustrated by applying it to the hypothetical case of the UK’s Marston Vale eco town. It was found that the approach is capable of simulating the optimal growth of a network, from both a single heat source or separate islands of growth, as well as the optimal marginal expansion of an existing district heating network. The proposed approach can be used by decision makers as a framework to determine both the optimal phasing and extension of district heating networks and can be adapted simply to various, more complex real-life situations by introducing additional constraints and parameters. The versatility of the base formulation also makes it a powerful approach regardless of the size of the network and also potentially applicable to cooling networks. International Journal of Sustainable Energy Planning and Management, Vol 9 (2016)

Note: This is a preprint of paper #2005 presented at the 14th European Wave & Tidal Energy Conference (EWTEC) 2021 in Plymouth, UK. The final version of paper with the same title can be found in the EWTEC 2021 proceedings. Abstract: In order to accurately reflect the cost estimates of lift-force Wave Energy Converters (WECs), a parametric cost model is developed. The definition, establishment and description of the parametric cost model is the purpose of the present article. The parameters of the cost model include the costs of developing and consenting, of the wave energy converter, of the balance of plant, of the installation and commissioning, and of decommissioning. To carry out the initial techno-economic analysis, the widely used parameters Capital Expenditures (CAPEX) and Operational Expenditures (OPEX) will be utilised and an economic modelling framework is suggested to carry out the assessment. For this purpose, the parametric cost model will be incorporated in the Danish COE Calculation Tool, which is a transparent and simple Excel-based software, free-to-download, that since 2014 has assisted many users in estimating the cost of energy of a wave energy device when operating at different locations. A description of the added capabilities and updates of the Tool will also be described in the article. Lastly, an example of the application of the Tool to three different configurations of the LiftWEC concept, where the parametric cost model is used, is presented. This work was produced as part of the LiftWEC Project. This project has received funding from the European Union's Horizon 2020 research and innovation programme under grant agreement No 851885. This output reflects the views only of the author(s), and the European Union cannot be held responsible for any use which may be made of the information contained therein.

China has promised to reduce nation’s carbon dioxide emissions in 2020 by at least 40% of its 2005 levels. This paper proposes that interregional industrial shifts might enable China to meet this goal. A Dorfman-Samuelson-Solow model is presented by using an environmental multiregional input-output table of China in a linear programming format and at given national carbon targets, with aim of maximizing national GDP, under constrains for both demand-supply balance and energy-use change within practical limits. In each province, excluding the energy preserved in the secondary energy, final consumption of 39 manufacturing commodities accounted by bottom-up and top-down methods, final consumption of other sectors, energy transition and loss are calculated by converting 20 energy types into carbon emissions. The model suggests that moving the energy and heavy industries out of China’s North Coast would help considerably, GDP losses could be counteracted by raising the output of high-tech industries in the South Coast and of selected services across most of China’s regions. Moreover, adjusting the energy mix toward cleaner resources would alleviate some pressure to reduce carbon emissions of heavy industry throughout China and of the energy industry in Central China. Superseded by a newer version.

Purpose Following the boom of shale gas production in the USA and the decrease in the US gas prices, increasing interest in shale gas is developing in many countries holding shale reserves and exploration is already taking place in some EU countries, including the UK. Any commercial development of shale gas in Europe requires a broad environmental assessment, recognizing the different European conditions and legislations. Methods This study focuses on the UK situation and estimates the environmental impacts of shale gas using lifecycle assessment (LCA); the burdens of shale gas production in the UK are compared with the burdens of the current UK natural gas mix. The main focus is on the analysis of water impacts, but a broad range of other impact categories are also considered. A sensitivity analysis is performed on the most environmentally criticized operations in shale gas production, including flowback disposal and emission control, by considering a range of possible process options. Results and discussion Improper waste water management and direct disposal or spills of waste water to river can lead to high water and human ecotoxicity. Mining of the sand and withdrawal of the water used in fracking fluids determine the main impacts on water use and degradation. However, the water degradation of the conventional natural gas supply to the UK is shown to be even higher than that of shale gas. For the global warming potential (GWP), the handling methods of the emissions associated with the hydraulic fracturing influence the results only when emissions are vented. Finally, the estimated ultimate recovery of the well has the greatest impact on the results as well as the flowback ratio and flowback disposal method. Conclusions This paper provides insights to better understand the future development of shale gas in the UK. Adequate waste water management and emission handling significantly reduce the environmental impacts of shale gas production. Policy makers should consider that shale gas at the same time increases the water consumption and decreases the water degradation when compared with the gas mix supply. Furthermore, the environmental impacts of shale gas should be considered according to the low productivity that force the drilling and exploitation of a high number of wells.