Abstract

This article aims to present the results of a case study of the use of Massive Open Online Courses as a digital learning strategy to promote education for sustainable development. The research focuses on the results of four Massive Open Online Courses offered to more than 17,000 participants, a case study research method was carried out to identify the didactic activities recommended to integrate on the Massive Open Online Courses of education for sustainable development. Among the results, it was found that challenge-based learning didactic activities develop participants’ skills that can be transferred to real-world scenarios and allow learning to become more profound and durable. The results also show that a better understanding of the network dynamics to explore how to develop a robust peer-learning environment is necessary. Future works are recommended to explore the potentials of big data to anticipate the needs of the participants’ digital skills.

Abstract

The widespread use of fossil fuels and their limitation leads to find other sources of energy. Solar thermal energy is a possible solution. There are many projects that use renewable energy. Solar thermal energy can be easily used for heating. However, there are problems in the efficiency of solar collectors, the loss of heat, the consistency of heat supply, temperature and weather conditions, the biggest problem being the heat storage. In this paper is provided an overview of the methodologies for thermal integration of solar heating systems implemented in various projects and research. Solar heating systems have different designs and can generate heat in different temperature ranges. The main emphasis in this comprehensive overview is the systematisation of the various methodologies used in the integration of solar heat in production. In principle, solar heating systems are directly connected to the production systems. Furthermore, a few methodologies like Pinch technology, mathematical modelling and cogeneration
are included.

Abstract

The themes of energy conversion with low environmental impact and energy recovery, will have, in the near future, a high potential for development for naval applications. The containment of pollutant emissions can be achieved by an innovative mini gas-steam combined cycle with thermal energy cogeneration to feed the ship thermal utilities, in place of or alongside the electric diesel engines currently used. The present work is focused on the definition of the architecture of the system, by selecting optimal thermodynamic cycle parameters and power repartition, as well as on the choice and sizing of the individual components to obtain a compact and high efficiency system. The proposed basic mini-cycle consists of a gas turbine of about 1.5 MW and a steam turbine of about 0.5 MW. For an overall electrical efficiency of about 28%, a total return (thermal + electricity) of 75% can been achieved. An example of plant providing larger power, in a partially modular arrangement is also proposed.

Abstract

In this paper, i am developing a unique optimization based real time inland load management algorithm that takes into account load ambiguity in order to minimize the energy payment for each residential user, as well as reduce the peak to average ratio to overcome the drawbacks in the stability of electrical grid. By categorizing the all residential load in different classes, i.e. must run, interruptible and uninterruptible appliances, i used the real time pricing scheme for load management. However, real time pricing creates the peak profiles when the energy demand is too high, that’s why i used the combination of real time pricing and inclining blocks rates model to improve the grid stability by reducing the peak to average ratio. A simulation results show that the proposed algorithm efficiently and effectively reduced the overall residential energy cost as well as peak to average ratio of our model for data provided.

Abstract

Apricot kernel shells are naturally available source of biomass with potential for conversion to clean energy through a thermo-chemical process such as pyrolysis. To facilitate further process development, an advanced mathematical model which represents the process kinetics is developed and validated on the thermal decomposition studies using simultaneous thermal analysis, over a temperature range of 30-900 °C, at four heating rates of 5, 10, 15 and 20 °C min⁻¹, under argon atmosphere. Model-free analysis and numerically developed methods were utilized for determination of effective activation energies, pre-exponential factors and the fractional contribution. A novel approach is introduced in order to determine actual pseudo-components of studied biomass that are included in its composition. The comparative study of the obtained kinetic results was also presented. The results obtained strongly indicated that the pseudo-component reaction modelling method could be employed to predict the experimental devolatilization rate and biomass composition with a high likelihood of success.

Abstract

Abstract

The Journal of Sustainable Development of Energy, Water and Environment Systems (JSDEWES) is an international journal dedicated to the improvement and dissemination of knowledge on methods, policies and technologies for increasing the sustainability of development by de-coupling growth from natural resources and replacing them with knowledge based economy, taking into account its economic, environmental and social pillars, as well as methods for assessing and measuring sustainability of development, regarding energy, transport, water, environment and food production systems and their many combinations.

In total 48 manuscripts were published in Volume VII, all of them reviewed by at least two reviewers. The Journal of Sustainable Development of Energy, Water and Environment Systems would like to thank reviewers for their contribution to the quality of the published manuscripts.

Abstract

Conserving water has always been very important for California especially during drought seasons, due to the fact that California geographically consists most of the hot and dry deserts. The goal of this project is to create an automatic recommendation irrigation system for the purpose of minimizing water use but keeping lawn grass still green. In this project, a mathematical model has been developed and big data analytic techniques have been applied to achieve the goal using the lawns of Harvey Mudd College as an example. The major results of this project include a smart irrigation algorithm by taking weather conditions and human’s induced irrigation patterns and an application to notify the user the irrigation rate calculated automatically by the newly developed algorithm. The method here is scalable to different lawns whether owned by an individual or by an organization as long as there is historical irrigation data available. In conclusion, this method saves money, minimizes water pollution, and preserves water resources especially for drought regions in the world.

Abstract

Active modes of transportation are essential for the promotion of sustainable mobility. Increasing cycling and walking participation has the potential to improve various aspects of traffic congestion and contribute to human health. The goal of this study was to analyse the factors that influence the choice of active modes of transport on a university campus at Joinville in southern Brazil. An online cross sectional survey of students from two nearby universities was also conducted. Based on quota sampling, participants were surveyed regarding their mode of transport to and from campus, as well as their place of residence, socioeconomic data and trip information. A total of 284 responses were received, where only 22.5% of trips were made using active modes of transport. A binomial logistic model was used to identify the factors that influence modal choices. The results of this study indicate that modal choices are influenced by travel time, university, income, and marital status.

Abstract

This study produces a technical and economic analysis of a farm- fed biogas plant that utilizes cow manure to produce electricity and heat via combined heat and power unit. The electricity generated is directly injected into the grid while heat is used within the biogas plant. The biogas system design was done depending on number of cows in the farm, which denotes the amount of manure available as feedstock. The economic performance of the proposed biogas plant was evaluated using various economic indicators. The levelized cost of electricity and the avoided greenhouse gas emissions were calculated too. The preliminary design and economic feasibility results proved the profitability of the manure-based biogas systems on wide range of farm sizes. The net present values of a 100-cow, 500-cow, 1,000-cow, 1,500-cow and 2,000-cow farms were all positive. The internal rate of return values were 11%, 12%, 13%, 16% and 17%, respectively, and the levelized cost of electricity values were 0.071, 0.069, 0.064, 0.055 and 0.055 JOD/kWh, respectively. The study also produced a design for a centralized anaerobic digestion plant depending on Jordan resources. The government role in promoting biogas-based electricity was discussed too.

Abstract

Waste heat utilization is shown to have the potential to decrease greenhouse gas emissions globally. The purpose of this case study is to illustrate how the utilization of waste heat to decrease municipal boundary greenhouse gas emissions may increase such emissions within wider boundaries. The case study assesses the utilization of waste heat generated by a data center. In this paper, we analyze the implications within Scopes 1-3 of the Greenhouse Gas Protocol together with attributional and consequential life cycle assessment principals. Only Scope 1 showed negative greenhouse gas emission implications. In order to achieve negative Scope 2 emissions, approximately half of the waste heat would need to be utilized, which is the purpose of further site development.
In order for negative Scope 3 emission implications, electricity production changes are needed or local municipal replaceable greenhouse gas emissions would need to be much higher.

Abstract

Due to its low share of energy-related emissions, energy systems models have overlooked the implications of technological transition in the agricultural sector and its interaction in the wider energy system. This paper explores the role of agriculture intensification by using a novel agricultural-based energy systems model. The aim is to explore the future role of Brazil’s agriculture and its dynamics with other energy sectors under two carbon constraint scenarios. The main focus has been to study resource competition between sugarcane and natural gas at a country level. Results show that in order to meet the future food and bioenergy demand, the agricultural sector would start intensifying by 2030, improving productivity at the expense of higher energy demand, however, land-related emissions would be minimised due to freed-up pasture land and reduction in deforestation rates. Additionally, the development of balanced bioenergy and natural gas markets may help limit the sugarcane expansion rates, preserving up to 12.6 million hectares of forest land, with significant emissions benefits.

Abstract

Total Site Centralised Water Integration is an innovative system of reusing water among industries at an industrial site through the use of a Centralised Water Reuse Header. This allows industries along the Centralised Water Reuse Header to exchange water while the systems are managed and operated by a third-party. However, the suitable number of Centralised Water Reuse Header and the optimum range concentration are key factors yet to be considered. This paper presents a methodology to determine the optimum number as well as the optimum range of Centralised Water Reuse Header concentration. The approach is illustrated using a case study to demonstrate how different numbers of Centralised Water Reuse Header affects both the total savings enjoyed by consumers and the payback period for the operator’s investment for the system. Results of the study show that two units of Centralised Water Reuse Header offer operator of the system a payback period of 3.5 years with consumer benefitting a 50.9% of total cost savings on freshwater (76.8% reduction) and wastewater (89.6% reduction).

Abstract

The aim of this work is to analyse the thermal comfort and energy performance of a thermal heating chair for open plan office using field experiments, thermal comfort survey and energy simulations. A comprehensive review on the development of thermal chairs was carried out to highlight the present research gaps. The study developed a thermal chair prototype with controllable heating pads, incorporated into the back of the seat and back rest fabric. The field test was carried out in an office building in the UK during the winter. The study showed that the users set the thermal chair temperature between 29-45 °C. The field survey results of the thermal satisfaction survey showed that 19 out of 44 participants felt satisfied before using the device. While after using the thermal chair, the number of satisfied respondents increased to 34. The work also utilised Building Energy Simulation to further assess the thermal comfort and energy performance of the thermal chair. Three cases were simulated: non heated office chair with the zone thermostat maintained at 22 °C, non heated office chair with the zone thermostat at 16-20 °C and thermal chair with the zone thermostat at 16-20 °C.

Abstract

With the increasing cost associated with energy consumption, climate change and the greater awareness of the population to issues related to energy and environmental efficiency, energy conservation in buildings has been encouraged, along with the development of several solutions based on a more sustainable construction. Building cooling is the most challenging issue in the Mediterranean climate. The roof is one of the main elements of the building’s opaque envelope, where the choice of materials and the implementation of appropriate passive technologies determine the thermal performance of a building. The present work aims to assess the impact of natural ventilation of a roof cavity on the thermal environment of a dwelling house under Mediterranean summer conditions. An experimental study was developed in a small-scale prototype of a typical dwelling house, comprising a ceramic tile roof with vented eaves and insulated sub-tile panels according to the construction solution of the Humbelino Monteiro SA company. The thermal performance of this roof solution was assessed under real climatic conditions based on continuous measurements of the air velocity inside the air gap, the temperature of the air and the surface temperature of all roof layers. Weather conditions were also monitored continuously. Connected with the heat transfer mechanisms, the obtained temperature and air velocity profiles data were analysed and discussed.

Abstract

Microbial Electrolysis Cells are devices capable of converting the organic fraction present in the wastewaters into hydrogen. Integrating this relatively new technology into wastewater treatment plants can improve the energy balance and result in significant savings in greenhouse gases emissions. However, there are not many studies available in the scientific literature on the carbon footprint of these systems. This paper compares carbon footprint of a wastewater treatment plant located in South Spain, to the carbon footprint of this same plant in which the aerobic treatment is partially replaced by a Microbial Electrolysis Cell. The carbon footprint attributed to the construction of the plants was similar in both cases. However, the wastewater treatment plant with the Microbial Electrolysis Cell system would allow mitigating up to 2,700 t CO₂-equivalents, which represents a 42% saving in greenhouse gas emissions compared to the existing wastewater treatment plants.

Abstract

The Renewable Energy Program of Minas Gerais is one of the initiatives which aims at the intensification in the use of renewable sources in the state. The present paper applies a methodology to evaluate the effectiveness of such instrument to expand the number of renewable energy projects and its contribution to achieve the goals of the energy sector of the Brazilian Nationally Determined Contributions, that is, to increase the use of renewable energy by 45% until 2030. It has been observed that the expansion of the renewable energy sources at regional level has advanced by incentive policies with clearly defined goals and guidelines. However, the analyzed program does not attend to all the requirements and it is possible to conclude that the main state public policy of renewable energy expansion did not accomplish its objectives suggesting that a balanced mix of public policies must be implemented in order to promote an effective
energy transition.

Abstract

This paper presents the feasibility analysis of a small-scale low-temperature solar organic Rankine cycle power system. The heat transfer fluid for running the organic Rankine cycle system is hot water with a temperature of 120 °C provided by an array of evacuated tube solar collectors. The performance of the solar organic Rankine cycle system was investigated using two different working fluids over a wide range of the evaporation temperature. Technical and economic indicators such as the required solar collector aperture area, the total heat transfer surface area of the heat exchangers and the volume flow ratio between the outlet and inlet of the expander are among the key parameters used to evaluate the solar organic Rankine cycle. Thermolib toolbox 5.2 in conjunction with MATLAB/Simulink was used to predict the variation of the system performance. The results showed that the solar organic Rankine cycle system is able to achieve an overall system efficiency of 6.75% using a relatively low-temperature heat source. The results also showed that the solar organic Rankine cycle system requires smaller evacuated tube solar collector and heat exchanger areas when R245fa is used as the working fluid.

Abstract

Heating, Ventilating and Air-Conditioning systems in museums are called to properly control important microclimate parameters, not only for visitors’ wellbeing, but mostly for the preservation of works of art. Accordingly, in case of interruptions to Heating, Ventilating and Air-Conditioning systems, due to maintenance interventions or drawbacks, it is essential to guarantee the acceptable break from service to which possible damages for the works of art are related. In this regard, the aim of this work is to introduce a simple indicator to support curators in regulating the stipulation of contracts with external companies, a more effective management and maintenance of the Heating, Ventilating and Air-Conditioning systems will thus be achieved in order to preserve the works of art, by integrating into the contracts economic penalties related to the system’s service break period. The feasibility of this new procedure has been checked by means of a case study involving the “Museo Regionale” of Palermo (Italy).

Abstract

The Savonius wind turbine is considered as one of the best vertical axis wind turbines for harvesting the kinetic energy from the wind in the urban areas, due to magnificent features such as high starting torque, low construction and maintenance costs, simple design, and self-starting ability especially at low wind speed. However, the conventional style of the Savonius rotor suffers from low efficiency. Consequently, modifying the configuration of the rotor may be an appropriate solution for providing electricity to the communities with no access to the power grid. Thus, this study aims to enhance the performance of the conventional Savonius rotor with an external overlap by adding an inner blade to the rotor configuration. Hence, a comparison study between five new arrangements against the conventional rotor in terms of power coefficient (C_p) and torque coefficient (C_t) is performed through a two-dimensional simulation by using ANSYS Fluent 19.2. The k-ε/Realizable turbulence model is employed in the simulation.
Results conclude that inner blade with an angle of 120° increases the power coefficient by 41%, 39%, and 7% at tip speed ratio (TSR) = 0.7, 0.6, and 0.5, respectively.