Abstract

The pressure head generated by the upper reservoir of a pumped hydro energy storage system located at 500-700m elevation can also be sufficient for creating the pressure gradient required for a reverse osmosis desalination plant. Combined with the fact that many drought-stricken coastal areas have nearby mountains at the necessary elevation for these upper reservoirs, a symbiotic relationship can be ascertained through the co-location of a pumped storage hydropower (PSH) system with a reverse osmosis (RO) desalination system. Merging PSH and RO into one Integrated Pumped Hydro Reverse Osmosis (IPHRO) system [1] instead of implementing each individually could result in a number of benefits, including reduced capital investment, lower maintenance costs, and a natural mechanism for diluting the highly saline brine discharge generated from the RO process. This paper extends the work of Slocum et al. in 2016 [1], who first introduced IPHRO systems, by optimizing the amount of seawater diverted from the upper reservoir for energy recapture and fresh water production, respectively. For this multi-objective optimization, a new reverse osmosis model is created that utilizes a blend of empirical and fundamental equations based on the solution-diffusion model of membrane transport and boundary layer effects that naturally occur along reverse osmosis membranes. Doing so presents an attempt to increase the fidelity of the IPHRO system simulation model to better represent real-life scenarios, which will eventually aid in the IPHRO system’s large-scale adoption into energy and freshwater infrastructures.

[1] Slocum, A. H., Haji, M. N., Trimble, A. Z., Ferrara, M., & Ghaemsaidi, S. J. (2016). Integrated Pumped Hydro Reverse Osmosis Systems. Sustainable Energy Technologies and Assessments, 18, 80–99. https://doi.org/10.1016/j.seta.2016.09.003

Abstract

Many businesses have begun their digitalization journey. 4G/5G and internet of things (IoT) have made their entrance into the industries, universities, society, culture and clothing businesses with new tools and applications that supports for example virtual reality (VR), augmented reality (AR), and mixed reality (MR). AR is a technology that for example allows the ability to support and guide customers, supported by smart glasses and other devices, around the world when service technicians cannot travel to the customer. Despite a pandemic that, as one might think, should have made the introduction of AR go smoothly and quickly, this technology seems to be introduced with a slow pace. In this paper a smart framework for AR utilizing artificial intelligence (AI) will be explored. This literature study investigates a concept and suggest a framework for creating smart AR that learn from all errors handled over AR calls and thus builds up a database of errors and solutions. When services can be provided via smart AR, the opportunity is given to reduce travels, which in turn has a positive environmental impact and additionally contributes to an increased productivity when service can be given instantly when the error occur.

Abstract

Blinds systems, daylighting, natural convection, and shielding thermostat from heating appliances are known to reduce electricity consumption, reduce energy wastage, reduce energy bills, reduce spurious errors in thermostatic controls, reduces over-heating of compressors, reduces the incidence of burnt motors, and fire hazards. Predictive modeling using the multivariate logistic stepwise statistical procedure selects from a set of independent variables of electricity load management survey data gathered from Windhoek City, Namibia to develop the best and optimal model in the study. The results indicate that keeping heat-producing appliances away from the thermostat so that it can give accurate readings is highly interconnected to using blinds systems to reduce inlet heat in summer and heat loss in cold months. Also, small changes in data values can lead to large coefficient estimates and there is a perfect (100.0%) correlation between the dependent and independent variables. In addition, the proportion of the variance explained in the developed model was 97.0%. However, there were also no multicollinearity problems in the data and the developed model was optimal and fairly accurate.

Abstract

In order to integrate products of subordinate units and extend the use of new energy, a group company has built a micro-grid system composed of wind power, photovoltaic power and energy storage units, which loads at a certain place in Beijing. The system has completed the 240 hours(240h for short) trial operation of micro-grid and achieved good operation data. This paper introduces the architecture of the micro-grid, analyzes the 240h trial operation data, and discovers key points of designing the micro-grid.

Abstract

Phase change materials (PCMs) own huge latent heat to regulate the thermal energy storage of building envelope and maintain comfortable indoor temperature range. While there were various kinds of PCMs, of which thermophysical properties were different, making it difficult to prepare and select the most suitable PCM. In this study, three fatty acids and four polyols were used to prepare the binary composite PCM, and four composite materials were preliminarily selected based on the indoor temperature required by ASHRAE Standard. The weight of melting temperature, latent heat, thermal conductivity, density and specific heat capacity were quantified with the analytic hierarchy process (AHP). The expected ranking of PCMs was given through subjective weight distribution and consistency test, and the optimal PCM for active indoor thermal environment construction in winter was identified.

Abstract

This paper proposes a hierarchical predictive energy management strategy (EMS) for hybrid electric bus (HEB) with an intelligent state of charge (SOC) reference planning method. In the cloud layer, future driving cycle is acquired through the intelligent transportation system (ITS) and well-trained neutral networks of deep deterministic policy gradient (DDPG) are extracted to plan the SOC reference trajectory quickly. In the vehicle layer, back propagation neutral network (BP-NN) is used to predict the velocity in a short term and an optimal controller is designed to distribute power flows optimally. Simulation results show that the fuel economy is improved by 2.12% compared with DDPG and reaches 97.43% of dynamic programming (DP).

Abstract

With increasing concern related to carbon dioxide emission, concept of Zero Energy Building (ZEB) appears. Electric Vehicles are also considered environment friendly automobiles to reduce greenhouse gas emission. With global trends above, Building energy system should consider ZEB concept and electricity demand for EVs charging. Therefore, this thesis suggests reasonable problem-solving method to find the best optimal energy system design to meet ZEB condition. EVs charging demand is predicted from the fittest Machine Learning regression model. This result combined with Hourly Building Energy demand from EnergyPlus simulator. Last Genetic Algorithm and PROBID method will be applied to meet two objective functions : Annual Total Cost and Self-Energy Sufficiency ratio.

Abstract

Hydrogen energy is an indispensable technology to achieve carbon neutrality in China. Currently, closed-loop hydrogen-related technology still faces great challenge in hydrogen storage. Metal hydride hydrogen storage (MHHS) is one of the promising forms in increasing hydrogen storage density and technical security. Whereas, MHHS technology involves complex physical-chemical issues in heat-mass transfer and absorption reaction. Based on a multi-field coupling model, the present work focuses on enhancing the running performance of MHHS by pressure regulation. It is found that with suitable pressure, the thermal load on reactor bed has been weakened effectively at the cost of an acceptable reduction of reaction rate. The Tmax of RB was reduced from 98°C to 75°C at the variable pressure operation mode. The present research provides a guidance with pressure regulating operation for MHHS technology.

Abstract

To achieve the climate goal set by the Paris Agreement, negative emission technologies (NETs) will play an important role. Bioenergy with carbon capture and storage (BECCS) is one of the most promising of NETs. This work aims to find a suitable technology for capturing CO2 from fast pyrolysis, which include Monoethanolamine based chemical absorption (MEA-CC), temperature swing absorption (TSA) and calcium looping (CCL) are considered. By using validated models, the CO2 capture rate, CO2 purity and energy penalty are employed as key performance indicators to compare the performance of those technologies. It has been found that CCL has the highest CO2 purity, MEA-CC, TSA and CCL have similar CO2 capture rates and TSA has the lowest energy penalty. Results provide insights and suggestions about the selection of CO2 capture technology for pyrolysis.

Abstract

Green infrastructure (GI) is one of the important measures to deal with climate change. Under the call of carbon emission reduction, it is inevitable to find a combination scheme of green infrastructure with low cost, low carbon emission, and high efficiency. This study analyzes the carbon emission activities of three kinds of green infrastructure: biological retention pond(BR), green roof(GR), and permeable pavement(PP) in the whole life cycle. A three-objective optimization model is constructed by coupling Storm Water Management Model (SWMM) and Non-dominated Sorting Genetic Algorithm III (NSGA III), which is applied to a newly-build campus in China. According to different demands scenarios, the weight coefficient method is adopted to determine the optimal scheme. The optimal scheme takes carbon emission reduction as the most important objective consisting of 59.1%BR, 33.9% GR and 7% PP. The result shows that the suggested scheme has a larger GR area than PP. This study provides a method and framework for the optimal design of GIs from the perspective of reducing carbon emissions in the newly-build areas, which contribute to the general construction of Sponge City.