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In the process of society, high-density livestock farms have developed rapidly to satisfy the increasing demand for meat products. Excessive wastewater from the livestock farms accordingly brought multiple pollution and deteriorate the environment, with the wastewater containing abundant chemical energy regarded as futility. Furthermore, the ingredients of wastewater varied from distinct livestock farms as a result of different animal feeding habits. Consequently, it is a necessity for specific wastewater treatment applied to a certain farm to control various pollution incidents while effectively recovering the potential chemical energy in wastewater. Microbial fuel cell, a device that converts chemical energy in the organic matter directly into electrical energy by a microorganism, is expected to be integrated with the existing wastewater treatment systems to make up for the shortcomings of existing technologies, improve the treatment efficiency and energy recovery rate. Therefore, it is a predictable trend for the microbial fuel cell to be combined with the traditional farm wastewater treatment system. This article demonstrates two traditional manure treatment methods: composting and biogas fermentation, followed by an evaluation of four advanced wastewater treatment technologies merged with microbial fuel cell. It is concluded that incorporating microbial fuel cells with separate wastewater treatment system will be a consequential sustainable development strategy in the future, with the purpose of fecal water treatment and energy recovery efficiently achieved.

The Cogeneration laboratory is a research facility in the University of Málaga (UMA) that allows for the behavioural study of a renewable energy installation combining solar resources and micro-CHP. Energy generation in the system is provided by a 3 kWp photovoltaic array, two solar thermal connectors and a Whispergen EU1 Stirling micro-CHP unit. Energy storage in the facility is provided by water tank and lithium-ion battery. This laboratory is managed through a programmable Mitsubishi PLC that permits the simulation of different thermal and electrical load profiles, as well as the mode of operation. The electrical energy management is controlled by the solar inverter. Environmental data, are measured using a top of the line weather station.The system’s real time status is logged through the programmable PLC. All this data is transferred and analysed in a purpose-built MATLAB-based software, where power and energy balances are conducted, efficiencies are calculated, and a CO2 emissions evaluation is studied.The CO2 emissions analysis is carried to evaluate the carbon dioxide emissions generated by the facility when the electrical and thermal demand are provided by the joint solar and micro-CHP system. These emissions come from the burning of natural gas in the micro-CHP Stirling engine, and the usage of electricity from the grid. With the current mode of operation, a reduction of up to 70% in CO2 emissions has been achieved, with an energy generation that exceeds the demand.

The increasing use of variable generation technologies (VGTs) in power systems, such as wind and photovoltaic generation, has introduced new challenges in the definition of capacity remuneration mechanisms for promoting system reliability. In this context, in this article we propose a novel framework for determining the capacity value of VGTs to contribute to the generation system adequacy, as well as a corresponding method for allocating capacity payments in hydrothermal power systems. We show that the capacity value of VGTs increases with the presence of water reservoirs, since VGTs help relieving hydropower plants from using scarce water resources during off-peak hours thus making more resources available to supply the demand during peak hours.

Many earlier studies have assessed the DH generation mix without taking explicitly into account future changes in the building stock and heat demand. The approach of this study consists of three steps that combine stock modeling, energy demand forecasting, and simulation of different energy technologies. First, a detailed residential building stock model for Herten is constructed by using remote sensing together with a typology for the German building stock. Second, a bottom-up simulation model is used which calculates the thermal energy demand based on energy-related investments in buildings in order to forecast the thermal demand up to 2050. Third, solar thermal fields in combination with large-scale heat pumps are sized as an alternative to the current coal-fired CHPs. We finally assess cost of heat and CO2 reduction for these units for two scenarios which differ with regard to the DH expansion. It can be concluded that up to 2030 and 2050 a substantial reduction in buildings heat demand due to the improved building insulation is expected. The falling heat demand in the DH substantially reduces the economic feasibility of new RES generation capacity. This reduction might be compensated by continuously connecting apartment buildings to the DH network until 2050.

Buildings are key actors of the electrical gird. As such they have an important role to play in grid stabilization, especially in a context where renewable energies are mandated to become an increasingly important part of the energy mix. Demand response provides a mechanism to reduce or displace electrical demand to better match electrical production. Buildings can be a pool of flexibility for the grid to operate more efficiently. One of the ways to obtain flexibility from building managers and building users is the introduction of variable energy prices which evolve depending on the expected load and energy generation. In the proposed scenario, the wholesale energy price of electricity, a load prediction, and the elasticity of consumers are used by an energy tariff emulator to predict prices to trigger end user flexibility. In this paper, a cluster analysis to classify users is performed and an aggregated energy prediction is realised using Random Forest machine learning algorithm. This paper is part of a project that has received funding from the European Union’s Horizon 2020 research and innovation programme under grant agreement No 768614. This paper reflects only the author´s views and neither the Agency nor the Commission are responsible for any use that may be made of the information contained therein.

Energy systems are a typical example of complex and dynamic systems and the study of their structure is of particular interest in theoretical and practical terms. Becoming the main trend of diversification and, renewable energies play important role in the evolution and dynamics of energy balances at the international, national, and local levels. Usually, natural sciences use Information Theory and the concept of entropy to assess diversity, uncertainty, and chaos in systems with a high number of components. An alternative approach to assess system complexity is to consider these issues from point of view of the concentration of resources, dominance, and hierarchy in the interactions between system components. This report presents an original method developed by the author for assessing the hierarchy in energy mix structures and the role of renewable energies. The author’s studies in the field of energy explore the evolution of markets and energy balances (energy mixes) on an international, regional and national level with a special focus on the European Union and Bulgaria. The hierarchy approach provides results in a more logical, objective, and balanced format and improves the analysis in terms of energy security and diversification. In this paper, is presented a research on the structure of the energy mix in Bulgaria.

In recent years, the scientific community has been concerned about the threat of global warming. This phenomenon is due to the increase of greenhouse gas emissions greenhouse gas emissions due to human activity. Renewable energies present themselves as a potential solution to reduce to reduce greenhouse gas emissions. Among the promising means of production As part of its policy of promoting renewable energy, the Cameroonian government launches each year projects in this area, hence the need to study the various sites and according to the parameters that are most often stochastic, hence the problem of choosing the type of wind power choose and implement. Thus this paper proposes a method of estimating the power produced according to the wind speed data of the scale coefficient and the shape on the station P/30 of Douala of the site of ASECNA - Douala Cameroon over a period of one year which presents different characteristics on the four seasons of the coastal areas of Cameroon by using the distribution of Weibull and by proposing another method using artificial intelligence ; This instability offers the opportunity to study other methods of power estimation using, as in this work, a multilayer perceptron type neural network. Based on the Weibull parameters, the power estimation is done by both approaches according to the different coastal seasons: hard dry season, short rainy season, short dry season and long rainy season. In addition, the form factor and scale factor fluctuated over the year from 1.36 to 1.94 and from 2.74 m/s to 3.80 m/s for different periods respectively. It was found that the average wind speed is 1.309 m/s, the average power for this site is 289.46 MW, and the months of March and July have high powers because the winds are warmer in these periods. For estimation we used a multi-layer perceptron consisting of: 03 input layers (wind speed, form factor and scale factor), 02 hidden layers of 10 neurons each and one output layer (wind turbine power), for training we used the gradient back-propagation algorithm using Matlab software. After an average of 200 training runs and a training step of 0.001, we obtained an RMSE for each of the four seasons of 0, 0065361; 0.00165361; 0.00052543; 0.0000011564. It was concluded that the algorithm improves the accuracy of power estimation by the MLP model and can be recommended for wind turbine power estimation.

To achieve national and international climate goals, the greenhouse gas emissions from the building sector must be reduced. One option is the use of renewable energies, which must be stored. Building parts with thermal activation have the potential to store heat. As those building parts feature new active energetic functionalities – active heat storage and heating – they are called multifunctional building parts (MBP). To investigate the potential of MBP, a thermal model is deployed and verified. The model is used to examine the influence of the distance between thermal activation and the MBP’s inside.

Within the energy transition context, private and public decision-makers must choose between different energy scenarios. Hence, environmental, and social impacts incurred from the development of renewable energies need to be investigated to ensure their alignment with energy transition objectives. Social Life Cycle Assessment (S-LCA) is one of the most appropriate methods to analyse social and socio-economic impacts with a life cycle perspective. However, social impacts included in sustainability analyses of energy systems mostly focus on employment or health and safety issues. Few studies in the literature present a rigorous approach to account for social impacts affecting different stakeholder categories. The present work is supported by a close collaboration with key industrial partners of the energy sector to overcome the above-mentioned limitation. Hence, it contributes to the definition of the goal and scope phase of a S-LCA study through the integration of companies’ perception. Thus, it aimed to highlight the priority of social impact subcategories and related stakeholdersin the context of offshore wind farms (OWF). As a result, a core set of impactcategories that were perceived as the most relevant is proposed.

The considerable expansion of telecommunications infrastructure in non-electrified areas has led to massive consumption of non-renewable energy sources by diesel generators. The promotion of renewable energy technologies as an alternative to these diesel generators is until now confronted with the problems of Capital Expenditures and system reliability. The hybridization of fossil fuels with renewable energies would make it possible to find a better quality/cost/environment ratio for the supply of off-grid telecommunication base stations (BSs).This paper presents the analyses of eight different hybrid energy systems dedicated for telecommunications equipment with a BS antenna as case study. The techno-economic analysis of hybrid energy system comprises solar, wind and the existing power supply. All the necessary modelling, simulations, and techno-economic evaluations are carried out using the assessment software package HOMER (Hybrid Optimization Model for Electric Renewable). The result shows that adding solar PV to the existing system is the optimal option. For the site studied powered by grid and diesel generator, the hybrid PV-diesel-grid with storage battery system is the best optimal system configuration for the chosen antenna with an initial capital cost of 34,619$, a Net Present Cost (NPC) of 55,588$ and a Cost of Energy (COE) of 0.39$/kWh.

The use of Information and Communication Technology (ICT) in the energy sector is becoming increasingly common. From data collection, recording and dissemination of energy information to design, planning and management of energy systems, scientific computing skills and tools, amount them programming languages. Depending on the problem to be solved, the choice of programming language is often very decisive for achieving the expected results. This article presents an analysis of the state of art of programming languages used in the energy domain and propose a case study of the programming languages to be used depending on the problem to be solved renewable energies sector. Programming languages for scientific computing are divided into two main classes: General Purpose Languages (GPL) and Domain Specific Languages (DSL); knowing a GPL make one better at using DSL. The analysis carried out shows that in energy engineering, the most used GPLs are C++ and python. Likewise, the most prominent DSLs are Julia, R and Matlab. The most suitable language for scientific computing, data science, visualization, and high-performance computing problems is Python. However, Julia which is in full expansion is not to be overlooked as it is dedicated to energy.

Demand response (DR) has effectively maximized renewable energies integrated into energy supply systems. This paper investigated DR benefits on three building types and the district heating (DH) production of a community consisted by these buildings in German conditions. Firstly, the buildings and the DH production were simulated without DR by tools IDA-ICE and HGSO, separately. Secondly, the three buildings were simulated by a rule-based DR control. After that, the tool HGSO calculated the total production costs and CO2 emissions based on the power demand with DR. The results show 2.8%-4.8% heating cost savings by DR for different building types. For DH producers, DR application reduces the total DH demand and CO2 emissions by 3.8% and 32.3 %, respectively.

The Cameroon rural western highlands, like most of the developing countries, undergoes a lack of electrical energy supply to make easier the lightning and the supply of tiny industries. During the last decades, the future of the technologies of renewable energies (Micro-hydroelectric power plant, photovoltaic panels, and micro wind tribune) is remarkable in the region. From this report, this study aims at analysing the installed capacities of those emerging technologies in order to determine the approbations degree of the local community and their influence on the sustainable development of the region. The primary and secondary data are obtained by the method of hypothec-deductive and mainly by snowball method, enabled us to evaluate three main types of renewable energy technologies in the region. The micro-hydroelectric power plants are the most important in terms of installed capacities. They are evaluated to 4936.7 KW (including the capacities of the colonial periods), an increase of 423.7 KW compared to 2014. The photovoltaic panels, which are the most prodigious one, are evaluated to 1070.362 KW, an increase of 936,47KWc. The micro wind turbines, which partially exist, are evaluated to 24.850 KW, an increase of 15.45KW. The analysis of the spatialization of these emerging technologies in this region shows a spatial and temporal growth of these technologies that testifies to their appropriation in the Western highlands of Cameroon.

Nowadays, the energy transition from fossil fuels to renewable energies is taking place worldwide. Every year, the amount of renewable energy installed increases dramatically. Many small-scale renewable energy technologies have been developed, for example at the household level, or at the environmental level as community-owned renewable energy. This research focuses on the development of renewable energy technology using the resource potential and local community wisdom of Glintung Water Street (GWS), a flood-prone area in Malang City. The objectives of the study were to analyze the potential of water resources in the study area to be developed as renewable energy, particularly under low flow conditions, and to investigate community support for the program of energy independence as a basis for developing a green economy to strengthen GWS as a food security village. This study uses 2 types of data, namely qualitative and quantitative data. Qualitative data is used to deepen the urgency of using renewable energy as alternative energy to replace PLN electricity. Meanwhile, the quantitative data collection consisted of 2 types of data, namely data on the measurement of the hydraulic characteristics of the flow as a source of driving force for the water wheel, and data on the community response and support using a questionnaire instrument. The results showed that the minimum flow to drive the water wheel under low flow conditions was 3 l/s. The maximum RPM recorded during waterwheel operation is 9 RPM, i.e. after it rained the night before the measurement, and the resulting voltage was 20 Volt. However, at higher flow conditions, the voltage generated by the waterwheel can reach 40 Volts. The community strongly supports the energy independence program although there are still doubts due to limited knowledge and experience in applying renewable energy technologies.

The worldwide environmental concern and awareness created a way towards the generation of pollution-free wind and solar renewable energies. Wind and Photovoltaic (PV) power plants of each 10 MW capacity located in the Shagaya area, west of Kuwait, were compared after one year of operation. The wind power plants recorded high capacity factors resulting in a yearly power production of 42.59 GWh, 21% higher than expected (contractual 31.160 GWh). It will reduce the emission of CO2 throughout the projected lifetime of 25 years by 118,303 tons. CAPEX (capital Expenditure) and OPEX (operation expenditure) were taken into consideration throughout the life of the plants along with investment costs resulting in a levelized cost of electricity (LCOE) for wind of 0.015 KWD/kWh or 0.046 USD/kWh, compared to 0.027 KWD/kWh or 0.082 USD/kWh for solar PV (44% lower than PV). Offshore, Boubyan Island, Northern Kuwait territorial waters, were found to be the foremost appropriate for wind energy generation, with Wind Power Density of more than 500 Watt/m2 in summer which is ideal for the high energy demanding season in Kuwait. The LCOE for offshore wind energy was 27.6 fils/kWh, compared to 39.3 fils/kWh for thermal power plants.

At the present time, operating hybrid air-conditioning systems that use solar energy to saving electrical energy while improving the performance has become necessary to protect the environment, reduce pollution and emissions caused by using fuels and gases. In Iraq, temperatures reach half the boiling point at summer, therefore the demand for air conditioning systems increases, air conditioning systems consume more than half of average electricity production which affects on reliability and stability of the electrical energy thus leads to a continuous power outage. So, the issue of using renewable energies becomes more attractive. Because of saving energy leads to ensuring the reliability of electricity and reduces the consumption of fuels and gases that pollute on the environment and negatively affect on the ozone layer. In the current research, the atmosphere of Baghdad city was used to collect solar thermal energy and convert it into thermal energy through an evacuated solar collector by water and combine it with a conventional air conditioner in the part that follows the compressor in order to reduce the electrical energy consumption on the compressor and increase coefficient of performance. Several tests were conducted on the proposed system to compare results with the conventional system and evaluate performance. The results showed that the coefficient of performance with the hybrid system became 8.97 more efficient instead of 4.27 compared to the conventional system, and the energy consumption decreased by 52%.

The active and reactive power sharing of distributed generation sources (DGs) connected to isolated microgrids with a single point of common coupling (mono-PCC) to which the loads are also connected has already been the subject of several studies. A high penetration rate of DGs based on renewable energies has as a logical consequence the development and implementation of mesh and more complex multi- PCC microgrids. In this paper, a developed droop control method for synchronization and power sharing between different DGs connected to a mesh islanded multi-PCC microgrid with many distributed generation sources (DGs) and different type of loads (including active load (CPL)) randomly connected to different PCCs is applied. Then, a state model of the entire mesh microgrid is developed integrating the generators with their controllers, power lines, droop algorithms and dynamic loads. This model is then used to study the asymptotic stability and robustness properties of the system. The simulation results confirm the effectiveness of the applied strategies for the synchronization of the different DGs to the microgrid while ensuring an efficient active and reactive power sharing. also, they confirm the validity of the developed state space model of the system.

According to the International Energy Agency (IEA-2013), Electricity alone does not create all the conditions for socioeconomic growth, but it is obviously essential to meet basic human needs and facilitate the development of economic activities. For the isolated areas with high wind potential and the island suffering from the electrification problems, the prospective solution is the use of renewable energies, especially wind energy. The present paper deals with a detailed statistical study on wind energy, its parameters, and variables on Socotra Island in Yemen, where that island is isolated from the main electricity grid in addition to the difficulty of providing electrical energy to this region in light of conditions in which Yemen has been living in recent times. The simulation results prove that the mean wind speed can reach a value ranging from 8.36 to 10.36 m/s, which is a large and enough speed to generate electricity using turbine farms. Based on the k and c Weibull parameters, the maximum probability at speeds 3 and 4 m/s is 0,052, while a value of 0,085 at speed 7 m/s is given by Rayleight distribution. Every result proved that Yemen has a good wind energy potential can utilize it for electrical energy production, and that strengthens the planning of economical wind turbines capacity for electricity production in the region.

The process of operating an air conditioning system by hybrid energy that uses solar energy for purpose of saving electrical energy with improving the performance from modern and environmentally friendly systems. With high demand for air-conditioning systems in summer in hot regions, especially in Iraq due to high temperatures, the issue of using renewable energies becomes more attractive due to the continuous interruption of electrical energy. Air conditioners in Iraq consume more than half of the average electricity production. Therefore, saving energy leads to ensuring the reliability of electricity and reduces the consumption of fuel and gases that pollute the environment and negatively affect on the ozone layer. In the current research, the atmosphere of the city Baghdad was used to collect the solar thermal energy through a vacuum solar collector and combine it with a conventional air conditioner in order to reduce the electrical energy consumption on the compressor and increase the coefficient of performance. Several tests were conducted on the experimental device for comparing results with the conventional device and evaluating performance. The results showed that the performance with the vacuum solar collector became more efficient 8.97 instead of 4.27 than with the conventional system, and the energy consumption decreased by 52%.

In the last decades, the public opinion has paid great attention to environmental pollution and global warming. Energy sector has a strong impact on environment. Thus, the use of renewable energies is becoming mandatory. The present paper deals with a study of ducted Savonius turbine performance as a function of geometric and operating parameters. Ducted turbines could be used as power take-off in multiple applications. In this paper, two main applications were studied. The first application is related to the possibility to install the turbine inside building with the purpose of architectonic integration of the system. The second one is related to wave energy harvesting. In both cases the same type of turbine was used to convert input energy (wind or wave energy) into electricity. Turbine performance were studied as a function of turbine overlap ratio, as well as air flux oscillating frequencies. On the basis of the obtained results, turbine performance increase in ducted configuration and a change in best overlap ratio was registered.

Kinetic energy is considered as one of the renewable energies. Substantial amounts of researches were conducted to investigate the feasibility of converting the kinetic energy into electricity. Nevertheless, most of these previous works emphasized on the selection of suitable materials and the design of power generator which tends to be complicated. In this paper, a simple and yet low cost mechanism has been proposed to enhance the performance and efficiency of energy conversion from kinetic energy to electricity energy by placing a mechanical footstep power generator on the hind foot region. A total of 45 individuals were invited to participate in the experiments and the experiment results are then compared with the theoretical results.

The use of renewable energies has seen a significant increase in energy demand in agriculture, in competition with solid, liquid or gaseous fossil fuels. Wood and other forms of biomass including energy crops, agricultural and forest biomass are transformed into energy through thermal, biological or physical processes. Thermo-chemical conversion, biomass gasification, is the most attractive technology that offers a high conversion efficiency compared to direct burning or rapid pyrolysis.

In our days, it seems to us that nobody can suspect it on the importance of water and energy for the human needs. With technological advances, the energy need does not cease increasing. This problem of energy is even more sensitive in the isolated sites where the use of the traditional resources proves often very expensive. Indeed, several constraints, like the transport of fuel and the routine maintenances of the diesel engines, return the search for an essential alternative energy source for this type of sites. It summer necessary to seek other resources of energy of replacement. Renewable energies, like photovoltaic energy, wind or hydraulic, represent a replacement solution par excellence and they are used more and more in our days more especially as the national territory has one of the solar layers highest with the world. The duration of insolation can reach the 3900 hours/year on the Sahara. The energy acquired daily on a horizontal surface of 1m2 is about 5kWh, that is to say meadows of 2263kWh/m2/year in the south of the country. The photovoltaic energy utilization for pumping of water is well adapted for more the share of the arid and semi-arid areas because of the existence in these areas of an underground hydraulic potential not very major. Another very important coincidence supports the use of this type of energy for the water pumping is that the demand for water, especially in agriculture, reached its maximum in hot weather and dryness where it is precisely the moment when one has access to the maximum of solar energy. The goal to see an outline on the general composition of a photovoltaic system of pumping, as well as the theoretical elements making it possible to dimension the current pumping stations.

The aim of the presented project is the technological development of hydrogen storage in methanol. This technology enables the carbon dioxide-based chemical storage of renewable energies as well as a decentralized supply of energy and hydrogen. Additional advantages are the very good compatibility with the existing infrastructure for liquid energy storage as well as the temporal decoupling of energy production and consumption. The latter can be managed independently, thus taking into account the fluctuating nature of wind and solar energy. The centrepiece is the use of new catalysts and processes that enable the chemical reactions in the methanol cycle under mild conditions.