• Energy Research

La présente recherche étudie la viabilité technico-économique de deux cas de systèmes énergétiques hybrides pour des solutions énergétiques durables dans une zone urbaine connue pour son ensoleillement abondant. Ces cas impliquent des combinaisons de photovoltaïque (PV) et de biomasse, avec des composants supplémentaires tels qu'un électrolyseur et une pile à combustible (FC). Le cas 1 comprend le PV/biomasse/électrolyseur, tandis que le cas 2 comprend le PV/biomasse/pile à combustible/électrolyseur/batterie, visant à produire de l'électricité et de l'hydrogène. Cet article a analysé les demandes d'énergie industrielle pendant les périodes hors saison, de mi-saison et de haute saison. Le système optimal pour le cas 2 est le plus fiable avec un panneau photovoltaïque de 23645 kW, un générateur de biogaz de 3800 kW, un convertisseur de 3821 kW, une pile à combustible de 250 kW, un électrolyseur de 600 kW, un réservoir de stockage d'hydrogène de 600 kg (Htank) et un système de secours de 30 batteries avec une stratégie d'envoi CC pour les consommateurs hors saison. Pour les utilisateurs en haute saison, le système dispose de 23789 kW de panneaux photovoltaïques, de 3800 kW de générateurs de biogaz, de 3861 kW de convertisseurs, de 250 kW de FC, de 1000 kW d'électrolyseur, de 1000 kg de Htank et de 30 batteries de réserve avec un plan d'expédition LF. Les résultats de la recherche suggèrent que l'utilisation de PV/biomasse/FC/électrolyseur/batterie est une stratégie plus réalisable et économique en raison des avantages du système. L'augmentation estimée du LCOE a été causée par la hausse du taux d'actualisation et des prix du carburant. La presente investigación investiga la viabilidad tecno-económica de dos casos de sistemas de energía híbrida para soluciones energéticas sostenibles en una zona urbana conocida por su abundante luz solar. Estos casos involucran combinaciones de energía fotovoltaica (PV) y biomasa, con componentes adicionales como un electrolizador y una celda de combustible (FC). El caso 1 comprende PV/biomasa/electrolizador, mientras que el caso 2 incluye PV/biomasa/pila de combustible/electrolizador/batería, con el objetivo de producir electricidad e hidrógeno. Este documento analizó las demandas de energía industrial en los períodos de temporada baja, media y alta. El sistema óptimo para el caso 2 es el más fiable con un panel fotovoltaico de 23645 kW, un generador de biogás de 3800 kW, un convertidor de 3821 kW, una pila de combustible de 250 kW, un electrolizador de 600 kW, un tanque de almacenamiento de hidrógeno de 600 kg (Htank) y un sistema de respaldo de 30 baterías con una estrategia de envío de CC para consumidores fuera de temporada. Para los usuarios de temporada alta, el sistema cuenta con 23789 kW de paneles fotovoltaicos, 3800 kW de generadores de biogás, 3861 kW de convertidores, 250 kW de FC, 1000 kW de electrolizador, 1000 kg de Htank y 30 bancos de salas de respaldo de baterías con un plan de despacho LF. Los resultados de la investigación sugieren que la utilización de PV/biomasa/FC/electrolizador/batería es una estrategia más factible y económica debido a los beneficios del sistema. El aumento estimado en el LCOE fue causado por el aumento de la tasa de descuento y los precios del combustible. The present research investigates the techno-economic viability of two cases of hybrid energy systems for sustainable energy solutions in an urban area known for its abundant sunlight. These cases involve combinations of photovoltaic (PV) and biomass, with additional components such as an electrolyzer and fuel cell (FC). Case 1 comprises PV/biomass/electrolyzer, while Case 2 includes PV/biomass/fuel cell/electrolyzer/battery, aiming to produce electricity and hydrogen. This paper analyzed industrial power demands across off-season, middle-season, and peak-season periods. The optimal system for case 2 is the most reliable one with a 23645-kW PV panel, a 3800-kW biogas generator, a 3821-kW converter, a 250-kW fuel cell, a 600-kW electrolyzer, a 600-kg hydrogen storage tank (Htank), and a 30-battery backup system with a CC send-off strategy for off-season consumers. For peak-season users, the system has 23789-kW of PV panels, 3800-kW of biogas generators, 3861-kW of converters, 250-kW of FC, 1000-kW of electrolyzer, 1000-kg of Htank, and 30 battery backup room banks with an LF dispatch plan. The research findings suggest that utilizing PV/biomass/FC/electrolyzer/battery is a more feasible and economical strategy due to system benefits. The estimated increase in the LCOE was caused by the rising discount rate and fuel prices. يبحث البحث الحالي في الجدوى التقنية والاقتصادية لحالتين من أنظمة الطاقة الهجينة لحلول الطاقة المستدامة في منطقة حضرية معروفة بأشعة الشمس الوفيرة. تتضمن هذه الحالات مجموعات من الخلايا الكهروضوئية (PV) والكتلة الحيوية، مع مكونات إضافية مثل المحلل الكهربائي وخلية الوقود (FC). تشتمل الحالة 1 على PV/الكتلة الحيوية/المحلل الكهربائي، بينما تتضمن الحالة 2 PV/الكتلة الحيوية/خلية الوقود/المحلل الكهربائي/البطارية، بهدف إنتاج الكهرباء والهيدروجين. حللت هذه الورقة متطلبات الطاقة الصناعية خلال فترات غير الموسم والموسم المتوسط وموسم الذروة. النظام الأمثل للحالة 2 هو الأكثر موثوقية مع لوحة PV 23645 - kW، ومولد غاز حيوي 3800 - kW، ومحول 3821 - kW، وخلية وقود 250 - kW، ومحلل كهربائي 600 - kW، وخزان تخزين هيدروجين 600 - kg (Htank)، ونظام نسخ احتياطي 30 بطارية مع استراتيجية إرسال CC للمستهلكين خارج الموسم. بالنسبة لمستخدمي موسم الذروة، يحتوي النظام على 23789 كيلو واط من الألواح الكهروضوئية، و 3800 كيلو واط من مولدات الغاز الحيوي، و 3861 كيلو واط من المحولات، و 250 كيلو واط من FC، و 1000 كيلو واط من المحلل الكهربائي، و 1000 كجم من Htank، و 30 بنك غرفة بطارية احتياطية مع خطة إرسال LF. تشير نتائج البحث إلى أن استخدام الكهروضوئية/الكتلة الحيوية/FC/المحلل الكهربائي/البطارية هو استراتيجية أكثر جدوى واقتصادية بسبب فوائد النظام. كانت الزيادة المقدرة في LCOE ناتجة عن ارتفاع معدل الخصم وأسعار الوقود.

To meet electricity requirements and provide a long-term, sustainable existence, remote areas need to promote renewable projects. Most of the time, wind and solar power sources are selected as renewable energy technologies to help satisfy some of the power requirements. Alternative approaches should be employed, considering the inconsistent characteristics among those resources, to offer efficient and long-lasting responses. Electricity production needs to be conducted with the help of a wide range of energy sources to be productive and efficient. As a result, the current research concentrates on feasible analyses of interconnected hybrid energy systems for such remote residential electricity supply. To help a remote area’s establishment decide whether to adopt renewable electricity technology, this paper evaluates the techno-economic effectiveness of grid-connected and standalone integrated hybrid energy systems. The electricity requirements for the entire selected remote area were determined first. Furthermore, the National Aeronautics and Space Administration, a national renewable energy laboratory, was used to evaluate the possibilities of green energy supplies. A thorough survey was performed to determine which parts were needed to simulate the interconnected hybrid energy systems. Employing the HOMER program, we conducted a simulation, optimizations, and economic research. Considering the net present cost, cost of energy, and compensation time, an economic comparison was made between the evaluated integrated hybrid systems. The assessment reveals that perhaps the grid-connected hybrid energy system is the best option for reliably satisfying remote areas’ energy needs.

There is increased focus to harness renewable energy resources in the 21st century to contain climate change and attain energy security. In this context, wind energy is attaining a significant marketplace to meet the ever-increasing electricity demand. This study, as such, undertakes wind energy assessment and forecasts wind power market penetration in Pakistan considering three different scenarios for the period 2020–2050. The modeling approach of this study is based on the Levenberg–Marquardt algorithm (LMA) optimization method, which is used to estimate the parameters of the logistic model to improve forecasting precision. It is revealed that around 55, 64, and 73% of wind potential could be technically exploited under each of the three scenarios, respectively. The Certified Emission Reductions (CERs) for each scenario are also estimated. The anticipated annual abatement of GHG emissions and CERs earnings at 30% capacity utilization factor is found to be 158 million CERs by the year 2050. These results suggest that wind energy offers great potential to attain energy security, environmental stability, and sustainable development in Pakistan. This study would assist energy professionals, government, and stakeholders to undertake wind energy market assessment and devise appropriate energy management plans.

Despite being a limited and scarce resource, the necessity and exploitation of fossil fuels are unstoppable in serving human demands. In order to supply energy demand without causing environmental damage, it is crucial to utilize a variety of renewable feedstock resources. Biochar, made up mostly of carbon, oxygen, and hydrogen, is the product of the thermochemical processes of pyrolysis, hydrothermal carbonization, torrefaction, and hydrothermal liquefaction. Biochar, once activated, has the potential to act as a catalyst in a variety of energy generation processes, including transesterification and fermentation. Transesterification is the process that is used to produce biodiesel from a variety of oils, both edible and non-edible, as well as animal fats in the presence of either a homogeneous or a heterogeneous catalyst. When selecting a catalyst, the amount of free fatty acid (FFA) content in the oil is considered. Homogeneous catalysts are superior to heterogeneous catalysts because they are unaffected by the concentration of free fatty acids in the oil. Homogeneous catalysts are extremely hazardous, as they are poisonous, combustible, and corrosive. In addition, the production of soaps as a byproduct and a large volume of wastewater from the use of homogeneous catalysts necessitates additional pretreatment procedures and costs for adequate disposal. This article examines the biochar-based fuel-generation catalyst in detail. At first, a wide variety of thermochemical methods were provided for manufacturing biochar and its production. Biochar’s chemical nature was analyzed, and the case for using it as a catalyst in the production of biofuels was also scrutinized. An explanation of how the biochar catalyst can improve fuel synthesis is provided for readers. Biodiesel’s transesterification and esterification processes, biomass hydrolysis, and biohydrogen generation with the help of a biochar catalyst are all reviewed in detail.

A meteorological drought study is performed using monthly time scale data from three separate locations in southern Sindh, Pakistan. Rainfall and temperature have been used to identify the drought. These data were transformed into drought indices known as the standardized precipitation evapotranspiration index (SPEI) and standardized precipitation index (SPI), which were derived using (the Hargreaves equation). In this study, two indices are compared for three separate meteorological stations Chhor, Mithi, and Badin where most socioeconomic livelihoods depend heavily on water. The SPEI is produced through a simple water balance combining precipitation and temperature, in distinction to the SPI, it just considers precipitation. In conclusion, our study showed that both indices were capable of detecting droughts that fluctuated in time across the reference period of 2004–2021. SPI and SPEI's direction of change was similar, however the impact on the drought condition varied. SPEI discovered more droughts with longer durations and greater with 13 moderate droughts at SPEI-3 for Chhor and Badin Station while Mithi indicated 8 moderate droughts during 2004-2021 and SPI-3 indicated 4 moderates for Chhor, Mithi and Badin indicated 6 moderate drought. Conversely, SPEI discovered more moderate-level droughts than SPI, however they were of shorter length and less frequent occurrence than the severe to moderate droughts. The findings imply that drought characteristics are significantly influenced by temperature variability.

AbstractPakistan has faced an electricity shortfall for over two decades despite various efforts taken at different levels. Though electricity supply in recent times has crossed the demand, the supply‐side stresses and deciding optimal power generation pathways have always been a challenge for policymakers and researchers. In this study using a LEAP energy model, following the sectoral electricity demand forecast, four supply‐side scenarios have been developed and analyzed for the study period 2017‐2055. In each scenario, referred to as Business as Usual (BAU), Renewable Energy Technologies (RET), Coal Power Penetration (CPP), and High‐Efficiency Low‐Emission (HELE) scenario, electricity generation, installed generation capacity, cost of production, and GHG emissions are estimated and compared for seeking long‐term optimal energy pathways for Pakistan. The study results reveal that for the end year (2055), RET is an environmentally sustainable scenario with an estimated electricity generation of 2421 TWh, which is enough to meet the electricity demand of 2374TWh. The GHG emissions under the RET scenario are estimated to be 857 million metric Tons, which are around 50% less than CPP and 40% less than the BAU scenario. However, the cost of generation is higher than BAU and CPP scenarios. The CPP scenario emerges to be cost‐competitive, however with the highest GHG emissions. This study thus suggests that convergence of RET with the CPP scenario could be an appealing option for Pakistan to meet increasing demand with energy security and environmental sustainability.

Today, using systems based on renewable resources is a suitable alternative to fossil fuels. However, due to problems such as the lack of access in all the times needed to supply cargo and high-investment cost, it has not been well-received. Therefore, in this research, the modeling of the photovoltaic system with battery storage has been done to supply the required load, and various scenarios have been evaluated in terms of economic parameters and reliability indicators of the studied system for a better understanding of the comparison indicators. It has been evaluated from two modes, one connected to the network and one disconnected from the network. One of the important results is the supply of 56% of the load by the photovoltaic cell in the presence of the grid, which, in this scenario, the electrical load is supplied by the photovoltaic cell and the grid is 164.155 kWh/yr and 128.504 kWh/yr, respectively.

Thermal energy in the industrial sector for process heating applications in the range of 50 to 250°C consumes about 35% of the global fossil fuel. Cascaded solar thermal systems are promising solutions to meet clean and uninterrupted thermal energy supply for industrial process heating. Well‐engineered cascaded arrangement of solar thermal collector (STC) and photovoltaic thermal (PVT) collector can attain an average solar fraction of more than 50%. In the present research, a solar‐assisted process heating system, wherein a STC integrated in series with PVT, has been designed to produce low‐ to medium‐temperature heat at higher solar fractions. Herein, thermal performance and economic viability of this novel system have been investigated and analyzed methodically. In the present research, a comprehensive TRNSYS simulation model is developed and validated experimentally. Results show that PVT integrated with heat pipe evacuated tube collector (PVT‐HPETC) and PVT integrated with flat plate collector (PVT‐FPC) system can generate thermal energy as high as 1625 and 1420 W with a thermal efficiency of 81 and 77% and exergy efficiency of 13.22 and 12.72%. Levelized cost of heat (LCOH) for PVT‐HPETC at process heat temperatures of 60, 70, and 80°C is 0.214, 0.208, and 0.201 MYR/kWh, respectively. It is worth to note that LCOH is less than the existing cost of heat generation which proves that these systems are economically feasible.