Abstract

The main purpose of this study is to obtain clean and efficient thermal energy by producing a direct current electric field to the flame reaction zone and to provide the thermochemical transformation of biomass (wood) particles controlled by the process produced in the field. In this regard, a mathematical model for modeling the thermal decomposition in the presence of an electric field, as well as, an experimental work has been developed. The equations of aerothermochemistry are coupled to balance equations for densities of charged species, and a Poisson equation for electrical potential is solved. The results obtained show that the presence of the electric field significantly improves the stabilization of the flame. The electron injection affects the char combustion process significantly. The field enhancement the combustion characteristics, and the flame reaction zone of field induced ion wind on biomass thermal decomposition was analyzed.

Abstract

In the present study, the thermal behavior of the high-temperature Concrete based Thermal Energy Storage (CTES) system is investigated using experimental study and simplified 1D dynamic modeling. The storage module is made up of shell and tube configuration. The shell side is filled with concrete as the energy storage material, and air is circulated in the tube (made of copper) side. The operating temperature range of the storage module is fixed in between 170 and 240 °C. The 1D dynamic modeling is developed using a set of equations, which helps to predict the heat transfer characteristics of the CTES module. In addition, the overall performance of the CTES module is investigated by integrating the developed model with real-time solar collector data and the seed dryer model. It is observed that, during the off-sun hours, the CTES module is capable of generating the hot air for the continuous drying of grape seed.

Abstract

Electrification of the transport sector is a crucial goal, which has to be accomplished in order to ensure sustainable development of worldwide economy and human civilization. Currently electrical vehicles (EV) constitute to only a small fraction of the whole automobiles fleet. It is however anticipated that a significant cost reduction of EV, technological progress in energy storage and increasing conventional fuel prices will change this situation dramatically. As with each new product on the market the customers behavior can be modeled only to a certain extent. Bearing in mind the above this paper investigates the potential impact of EVs’ charging station which is a part of an office building infrastructure. Various scenarios are analysed considering different charging strategies. Results indicate need for developing intelligent and forecasts based charging strategy.

Abstract

This work presents a Macro-Scale electrochemical model of a low temperature Solid Oxide Fuel Cell (SOFC) with a MIEC electrolyte. Low temperature SOFCs potentially merge high efficiency due to relatively high temperature, presence of a solid electrolyte, and lower production costs (among others) compared to really high temperature ones. Therefore, there is great interest on them despite they have not been thoroughly studied yet. The model has been compared with a Micro-Scale one found in the literature which closely reproduces experimental data. Assuming electrochemical reactions occurring just at the electrodes/electrolyte interfaces as usually done in high temperature operation (with “classic” YSZ electrolyte) has been found not to be accurate enough, thus ionic ohmic loss in the electrodes has been accounted. The final polarization curves matching has been quite good, but solving the charge conservation equations within the electrodes would definitely enhance the model accuracy and stability.

Abstract

Aiming at the problem that multi-energy microgrid involves the coupling of multiple energy sources and the difficulty of quantifying the supply capacity of each energy load, the evaluation methods of reliable energy supply intervals of multi-energy microgrid are proposed. Firstly, taking the multi-energy microgrid as the research object, a typical microgrid system model is constructed based on the energy hub model, and the concept of multi-energy microgrid energy supply capability is proposed. Secondly, considering the constraints of energy supply reliability, a reliable energy supply interval model of integrated energy microgrid is constructed. Thirdly, based on NSGA-2 multi-objective optimization, the solve method of reliable energy supply interval model of multi-energy microgrid is proposed. Finally, the effectiveness and practicability of the proposed model and method are verified by an example.

Abstract

In recent decades the oil demand in the transport sector is continuously increasing with rapid increase in the population growth and economic development, resulting in more greenhouse gas (GHG) emissions. Road transport sector in Algeria contributes the most in emissions due to 100% fossil fuel consumption. Government of Algeria launched the National Energy Efficiency Program (PNEE) in 2011 to reduce CO2 burden in the transport sector. The program was revised in 2016 with major objective of saving 15 million tonnes of oil equivalent (Mtoe) of energy consumption by fuel products. The objective of this study is to evaluate the impact of energy efficiency policies of Algeria on road transport sector in context of carbon footprints. In this work two scenarios i.e. Business as Usual (BAU) and Energy Policy scenarios were developed to determine the carbon emission reductions. The BAU scenario was developed based on historical data while the policy energy scenarios were prepared based on government energy policy program which was to promote liquefied petroleum gas (LPG) and natural gas in the road transport. The results described that implementing the government policy targets led to use of less polluting fuels and hence, reduction in CO2 emission to the environment.

Abstract

Pre-treatment and storage of agriculture residue are crucial for its supply chain. To investigate the effect of pre-treatment methods (i.e. torrefaction and compaction), the number of storage depot, and power generation technology on supply chain model, this work compared 7 scenarios in order to optimize supply chain model for power generation in China using corn stalk as feedstock. Furthermore, the influential roles of supply chain parameters on power generation profitability will be investigated through sensitivity analysis. It was found that combined heat and power based power generation shows significant profitability compared with electricity generation. The results approved that supply chain model reaches the highest profitability with compaction as pre-treatment method and 9 storage depots. According to sensitivity analysis results, the capital investment cost of power plant is the most influential parameter for supply chain profitability, the followed by is the purchasing price of corn stock residues.

Abstract

The renewable energy industry is widely utilizing biomass as one of the extraction sources. Pyrolysis is among the most commonly used technique to process biomass into desired fuels. Biomass mainly consist of cellulose, hemicellulose and lignin that will decompose differently during pyrolysis yielding valuable bio-oil, biogas and bio-char. Traditional experimental work to study biomass pyrolysis could be complex and time consuming. This study has utilized SuperPro Designer (SPD) as a modelling tool to investigate the pyrolytic behavior of biomass constituents and product distributions. The model was built based on kinetic studies of lignocellulosic reaction pathways. The obtained results were verified with experimental as well as literature data. The flexibility and accuracy of SPD model were also tested with different biomass species. The model was validated and can be used as a predictive and optimization tool for the study of biomass pyrolysis.

Abstract

This paper conducts and compares the computational modelling of two cooling and power systems, integrating organic Rankine cycle (ORC) with adsorption cycles. The kinetic sorption models of MnCl2-EG and MnCl2-EG-Ni@C are established and validated via the data in previous study. The result shows a higher thermal efficiency of utilizing adsorption units as the top user of the heat source. Moreover, it is demonstrated that using the novel sorbents with Ni@C could improve the cooling production and the thermal efficiency of the cogeneration system.

Abstract

In this paper, we analyze the implications of fully or nearly fully decarbonizing the European electric system by 2050. Future power mixes trajectories are computed with a 5 year time step at country level using eTIMES-EU, a bottom-up optimization model for the EU power sector. By comparing a near carbon neutral case (TGT90) with a fully decarbonized system (NEUTR), we discuss the additional costs, capacities and trading implications. Increasing the ambition from 90% mitigation goal to strict neutrality requires 32.6% more investments in 2050, 394 GW additional solar capacity in 2050 and more reliance on trade between countries.