Fossil Power Generation Research Articles

Performance Analysis of a Self-Decarbonizing Combustor

Abstract Hydrogen is envisioned to be a key decarbonization solution for fossil fuel-dependent power generation and aviation industries. At present, a significant fraction of the generated electrical power is derived from natural gas. As such, the external energy needed for hydrogen generation, often sourced from fossil fuels, results in CO2 emissions, compromising overall carbon neutrality. Instead, the processes of hydrogen generation can be energetically coupled with the combustion process, in situ, to eliminate external energy requirements. To that end, a novel self-decarbonizing combustor (SDC) has been conceptualized, integrating methane pyrolysis with the combustion process that can in principle decarbonize many contemporary power generation technologies. The underpinning methane pyrolysis process enables in situ pre-combustion capture of solid carbon, while simultaneously generating hydrogen. Consequently, CO2 emissions resulting from the combustion of processed, hydrogen-enriched fuel are mitigated. This study provides a comprehensive analysis, delineating the operating principle and the effect of some of the important governing parameters on the performance of the self-decarbonizing combustor. These parameters, including fuel temperature, residence time, pressure, and catalysis, are studied in the context of potentially applying the proposed concept to natural gas-based decarbonized electrical power generation. Investigating fuel chemistry, combustion exhaust, and carbon structure and morphology under varying process parameters enhances our comprehension of the SDC. Additionally, its self-sufficient nature eliminates the need for separate hydrogen production, storage, and transportation infrastructure, highlighting its potential as a scalable and realizable technology.

A techno-economic analysis of future hydrogen reconversion technologies

The transformation of fossil fuel-based power generation systems towards greenhouse gas-neutral ones based on renewable energy sources is one of the key challenges facing contemporary society. The temporal volatility that accompanies the integration of renewable energy (e.g. solar radiation and wind) must be compensated to ensure that at any given time, a sufficient supply of electrical energy for the demands of different sectors is available. Green hydrogen, which is produced using renewable energy sources via electrolysis, can be used to chemically store electrical energy on a seasonal basis. Reconversion technologies are needed to generate electricity from stored hydrogen during periods of low renewable electricity generation. This study presents a detailed techno-economic assessment of hydrogen gas turbines. These technologies are also superior to fuel cells due to their comparatively low investment costs, especially when it comes to covering the residual loads. As of today, hydrogen gas turbines are only available in laboratory or small-scale settings and have no market penetration or high technology readiness level. The primary focus of this study is to analyze the effects on gas turbine component costs when hydrogen is used instead of natural gas. Based on these findings, an economic analysis addressing the current state of these turbine components is conducted. A literature review on the subsystems is performed, considering statements from leading manufactures and researchers to derive the cost deviations and total cost per installed capacity (€/kWel). The results reveal that a hydrogen gas turbine power plant has an expected cost increase of 8.5% compared to a conventional gas turbine one. This leads to an average cost of 542.5 €/kWel for hydrogen gas turbines. For hydrogen combined cycle power plants, the expected cost increase corresponds to the cost of the gas turbine system, as the steam turbine subsystem remains unaffected by fuel switching. Additionally, power plant retrofit potentials were calculated and the respective costs in the case of an upgrade were estimated. For Germany as a case study for an industrialized country, the potential of a possible retrofit is between 2.7 and 11.4 GW resulting to a total investment between 0.3 and 1.1 billion €.

Implementation cost of net zero electricity system: Analysis based on Korean national target

We evaluated the costs of implementation of a sustainable electricity system with carbon net zero emission by 2050. To achieve this goal, it is assumed to reduce the use of fossil fuel-based power generation, increase carbon-free clean energy generation, and secure storage facilities. We compared the total costs including the capital cost of new generators and storage technologies, fuel costs, and emission costs by 2050. We also investigated the effects of various levels of carbon price, curtailment rates of renewable energy output, demand pattern shift, increasing nuclear power generation, building pumped hydro storage, and utilization of hydrogen storage as long-duration storage. One of our findings indicates that although a higher curtailment rate necessitates increased renewable energy installation to achieve national emission target, it leads to a reduction in total costs due to the decreased requirement for storage capacity. Our findings provided invaluable insights into the potential of these solutions to facilitate the transition to a more sustainable electricity system in South Korea and other countries with similar policy goals.

Renewable energy prosocial behavior, is it source dependent?

AbstractFacing increasing nonrenewable and environmental concerns with fossil power generation, renewable energy is being supported by government mechanisms. With the power generation cost of renewables generally higher than fossil fuels, determining the optimal level of these mechanisms requires an understanding of households’ prosocial behavior toward renewables. The issue is determining the magnitude households are willing to pay (WTP) for alternative renewables. Our hypothesis is this behavior varies by the type of renewable energy. As a test of this hypothesis, we apply a discrete choice experiment to measure households’ WTP. Results support our hypothesis with a positive WTP for solar energy, leading to a 62% reduction in solar subsidy, and a negative WTP for biomass and wind sources.

A novel on design and implementation of hybrid MPPT controllers for solar PV systems under various partial shading conditions

At present, fossil fuel-based power generation systems are reducing drastically because of their less availability in nature. In addition, it produces hazardous gasses and high environmental pollution. So, in this work, the solar natural source is selected for generating the electricity. Due to the nonlinear behavior of PV, achieving maximum voltage from the Photovoltaic (PV) system is a more tough job. In this work, various hybrid optimization controllers are studied for tracing the working power point of the PV under different Partial Shading Conditions. The studied hybrid optimization MPPT methods are equated in terms of oscillations across MPP, output power extraction, settling time of the MPP, dependency on the PV modeling, operating duty value of the converter, error finding accuracy of MPPT, algorithm complexity, tracking speed, periodic tuning required, and the number of sensing parameters utilized. Based on the simulative comparison results, it has been observed that the modified Grey Wolf Optimization based ANFIS hybrid MPPT method provides good results when equated with the other power point tracking techniques. Here, the conventional converter helps increase the PV source voltage from one level to another level. The proposed system is investigated by using the MATLAB/Simulink tool.

Multi-objective optimization, comparison of using different biomass fuels in hybrid energy system for electricity-distilled water production based on supercritical CO2 and humidification and dehumidfication cycles

Biomass-derived power generation presents various potential benefits compared to conventional fossil fuel-based power generation. Also, efficient integration of energy systems leads to higher sustainability and effectiveness. This paper presents a biomass-fueled energy system with two open and closed Brayton cycles in the waste heat, of which a humidification and dehumidification system is implemented. The usage of four different biomasses as the fuel of the gasifier is tested and put to comparison from the aspects of thermodynamics, economics, and environment. The Grassman diagram for each layout is presented to signpost the exact point of highest exergy destruction and irreversibility. The optimization based on machine learning techniques is conducted to pinpoint the exact optimum operational conditions. The results indicate that wood offers more sustainability compared to other biomasses, and the amount of energy efficiency, exergy efficiency, and freshwater flow rate produced for Wood biomass in the proposed system are 75.81 %, 36.98 %, and 0.4091 kg/s, respectively. Also, two optimization scenarios have been done for this study. In the initial optimal solution finding, effectivness, unit product cost, and carbon dioxide emission index are equal to 45.9 %, 12.6 $/GJ, and 0.7161 kg/kWh, correspondingly. In the latter scenario, the effectiveness, net power production, and production unit cost of products are equal to 45.9 %, 6580 kW, and 12.61 $/GJ, respectively.

6E evaluation of an innovative polygeneration system consisting of gas turbine cycle with CO2 capture, ejector refrigeration cycle, steam Rankine cycle, solar tower and MEDAD unit

The development of the energy systems in terms of technical performance and their assessment from an economic and environmental perspective has been a trending subject, lately. Due to global warming, the effectiveness of these systems has decreased. The pre-cooling technology of the incoming air is known as an influential factor to compensate for this limitation. In this study, we aim to provide a fossil fuel-based power generation system along with the solar energy, and upgrade it to a poly-generation system with the motivation to create an integrated set to meet the needs of power, cooling, heating, freshwater and CO2. In this framework, an integrated system consisting of gas turbine cycle (GTC) with CO2 capture, steam Rankine cycle (SRC), ejector refrigeration cycle (ERC), solar tower cycle (STC), hybrid multi-effect distillation adsorption desalination (MEDAD) is proposed, which presents a new design of a poly-generation system. The proposed system is modeled as a code in MATLAB to analyze energy, exergy, exergo-economic, exergo-environmental, emergo-economic and emergo-environmental (6E), and the validity of its thermodynamic results is compared with results obtained from simulation in Thermoflex. In addition, a parametric sensitivity analysis is performed that considers increasing the number of MEDAD stages, heating the air output from the air compressor (AC), pre-cooling the air entering AC to achieve the optimal operating conditions of the considered system in order to increase freshwater production, reduce fuel consumption and increase power generation. The results showed that the amount of freshwater produced with the correct use of thermal energy sources increases by 95.25 %, fuel consumption decreases by 22 % and net power of GTC increases by 5 %. Finally, the overall energy efficiency of the system in single generation (power production only) and multiple generation is 34.27 % and 65.65 %, respectively.

Statistical data-based prediction of carbon dioxide emission factors of China's power generation at carbon peak in 2030

China has promised to reach its peak carbon dioxide emissions by 2030. Power generation emits the most carbon dioxide in China. Fossil fuels are currently still the largest sources of energy for electricity generation in China. As the most commonly used method for estimating emissions from thermal power generation, emission factor data has a statistical lag, which brings inconvenience to carbon emission accounting and the formulation of energy conservation and emission reduction policies. It is of great significance to predict the emission factors of fossil fuel-fired power generation in China. In this paper, the correlations between the data of coal-fired, gas-fired, and oil-fired power generation from 2012 to 2019 and the emission factors of China's power generation and the correlations between the data of fossil fuel-fired power generation from 2006 to 2019 and the emission factors of China's power generation are evaluated using SPSS. On this basis, two models for predicting emission factors of China's power generation from 2020 to 2030 are established and the relevant data are obtained. The calculation results show that when the carbon peak reaches in 2030, the emission factor of China's power generation may be 0.6290 and 0.7363 corresponding to the two prediction models.

Distributed generation for Microgrid technology

Distributed Generation (DG) refers to the generation of electricity from various small-scale sources of energy such as solar panels, wind turbines, or micro-turbines, located near the consumers. Microgrids (MGs), on the other hand are localized and autonomous electrical systems that can operate independently or in connection with the main power grid. The integration of DG within MGs has gained significant attention due to its potential benefits. This arrangement allows for increased efficiency, improved reliability, and enhanced resilience in the delivery of electricity. Furthermore, it enables the utilization of Renewable Energy Sources (RESs), reducing reliance on conventional fossil fuel-based power generation. In an MG with DG, the power generation sources are dispersed throughout the grid, supplying electricity to nearby consumers. Depending on the availability and generation capacity of each source, the MG can efficiently balance the energy supply and demand. In cases where excess generation occurs, the surplus energy can be exported back to the primary grid or stored for future use. The decentralized nature of distributed generation in MGs also contributes to more excellent grid stability and reliability. If any part of the main grid experiences a power outage, the MG can continue to operate independently, providing uninterrupted electricity to the connected consumers. This feature is especially valuable in remote areas, critical facilities, or during emergencies, where maintaining a reliable power supply is essential.

ROLE OF EXTERNAL FINANCE AND INNOVATION IN ACHIEVING ECO-EFFICIENCY AND SUSTAINABLE DEVELOPMENT GOALS

Eco-efficiency is a biggest universal challenge and one-fourth CO₂ emission produce by World Transport sector. UN Sustainable development Goals Agenda-2030; Paris agreement of 2015 was most successful agreement between the advancing Global World to set a target, to meet Social-economic-environment success. The main objective of this study is to examine the effect of External finance and Power Diversity on Eco-efficiency and sustainable Development Goals; to identify the best financial and transport eco-power source. This study used two ways of data analysis; first, past and future trend analysis, and second, Regression, GMM and Robust measurement; first, External finance Trend of four countries, Japan has least dependent country, china only face dependency in FDI, while Pakistan major dependency on Remittances and ODA-Foreign-Aid. Fuel Consumption Trend; Japan Eco-efficiency policy is better than other three countries, but still away from Paris Agreement-Target-2030. Second; Regression and GMM results indicates external finance i.e. FDI, Remittances, ODA and Transport Power Source i.e. Oil and Electric high significant impact on eco-efficiency and SDGs; GDP highly significant inverse, health negative and Per-Capita GDP, Government Consumption positive relationships exist with Eco-efficiency and SDGs. The robust result indicates of validity and the sustainability. Study implication and recommendation are cleared; external finance has a modern finance source for technology enhancement and economy. Transport Cargo system need to be design according eco-friendly, UN SDGs Agenda-2030. Government need to enacting policies to encourage foreigner to invest eco-friendly project like modern technology enhancement, people to move away from gasoline and diesel transportation until modern technology eco-efficient, Electric power system is an alternative of fossil power generation toward CO₂ emission reduction.

High penetration of electric autorickshaw on national power system and barriers against the adoption of solar energy: A case study in Bangladesh

Peak hours' electricity demand is linearly related to carbon emission in fossil fuel-dominated power generation systems like in Bangladesh. Electric autorickshaws are becoming a burden for the national power system as their charging time coincides with the national peak hours. Solar electrification of the light-duty transportation sector is the focus of this work. This study identifies the uncontrolled growth of electric autorickshaws and their power consumption time as an alarming load for the national power system. To analyze the utilization of solar potential to reduce peak hours’ demand and identify the barriers underpinning the implication of solar potential in the autorickshaw sector are also the aim of this study. The results show that approximately 4660 MWh of electricity is consumed by autorickshaws in Bangladesh per day instead of the potentialities of approximately 23,000 MWh of solar energy generation capabilities per month in this sector. Cabalistic and plausible reasons behind not implication of solar potential in the autorickshaw sector are also analyzed. This study might be helpful for the related authorities in reducing peak demand and also solving the barriers responsible for not utilizing the solar potential.

How do we envision the sustainable society we want to create?

How do we envision the sustainable society we want to create? Professor Masahide Sakamoto uses Japanese pollution research to discuss how we can implement a better, more sustainable society. He uses two ideas that we should choose in order to realize a sustainable society: 1. If the inequality structure of the capitalist economy remains unchanged, each person should seek happiness in his or her own way within that structure. 2. Assuming that it is natural that there are differences in individual abilities, we should build a society in which there are no differences in human values, and we can respect each other as human beings. While there is no single definition of a sustainable society, he argues the introduction of renewable energy has less environmental impact than fossil fuel-based power generation systems. Fossil fuels can only be extracted in certain places, and disputes over ownership are likely to arise, whereas renewable energy can be used in any country with the right technology. This entails wars and conflicts over oil can be avoided, leading to the peaceful use of energy, and reducing post-disaster damage. Ultimately, the realization of a sustainable society will depend on what kind of socioeconomic system is designed by governments.

Sector coupling leading to low-carbon production of power and chemicals in China

A pathway to a carbon-neutral electricity-chemical nexus in China by 2060 is attainable. Sector coupling reduces fossil power generation by 10%, drives renewable curtailment rates to below 5%, and expands energy transmission capacity by at most 18%.

What evidence exists regarding the effects of photovoltaic panels on biodiversity? A critical systematic map protocol

BackgroundClimate change and the current phase-out of fossil fuel-fired power generation are currently expanding the market of renewable energy and more especially photovoltaic (PV) panels. Contrary to other types of renewable energies, such as wind and hydroelectricity, evidence on the effects of PV panels on biodiversity has been building up only fairly recently. PV panels have been linked to substantial impacts on species and ecosystems, the first and most obvious one being the degradation of natural habitats but they may also lead to mortality of individuals and displacements of populations. Hence, we propose a systematic map aiming to draw a comprehensive panorama of the available knowledge on the effects of photovoltaic and solar thermal (PVST) installations, whatever their scales (i.e. cells, panels, arrays, utility-scale facilities), on terrestrial and semi-aquatic species and natural/semi-natural habitats and ecosystems. This work aims at providing decision-makers with a better understanding of the effects of PVST installations and, therefore, help them further protect biodiversity while also mitigating anthropogenic climate change.MethodsWe will follow the collaboration for environmental evidence guidelines and search for relevant peer-reviewed and grey literature in English or French. The search string will combine population (all wild terrestrial and semi-aquatic species—e.g. animals, plants, fungi, microorganisms—as well as natural/semi-natural terrestrial habitats and ecosystems) and exposure/intervention (all technologies of PVST panels at all scales of installations and therefore excluding concentrated solar power) terms. A pre-built test list of relevant articles will be used to assess the comprehensiveness of the search string. Extracted citations will be screened at title and full-text stages thanks to pre-defined inclusion/exclusion criteria. Accepted citations will then be split into studies and observations, from which relevant metadata (e.g. taxon, exposure/intervention, outcome) will be extracted and their internal validity assessed through a critical appraisal. The database will be accessible alongside a map report which will draw a landscape of eligible studies. By describing studied populations, exposures/interventions, outcomes and internal study validity results, the report will identify potential knowledge clusters and gaps regarding the effects of PVST installations on biodiversity and ecosystems.

Prospective sectoral GHG benchmarks based on corporate climate mitigation targets

As climate change becomes firmly acknowledged as a financial risk, shareholders must consider corporate GHG performance to inform responsible investment decisions. To mitigate future climate risks, prospective benchmarks based on corporate climate mitigation targets are increasingly demanded by shareholders. However, existing benchmarks often lack sufficient sectoral coverage or fail to appropriately harmonize target metrics, scope, and corresponding timeframes. A harmonization process was developed which allows the calculation of sector-level prospective GHG benchmarks in terms of absolute or intensity GHG metrics. This process was applied to harmonize scope 1 and 2 emission targets of 1697 companies reporting in 2018 CDP questionnaires across 13 sectors using 2017 as the common reference year. Results indicate the importance of using a sectoral approach and applying a common reference year to avoid considering reductions occurring before the target was launched due to company choice of target reference year. In 2030, the lowest and highest median reduction rates values are −9% and −36% for fossil fuels and power generation sectors respectively. The findings obtained strongly suggest targeted percentage of reductions should not be the only metric considered when comparing corporate climate mitigation targets amongst peers. Target progress when the target was announced and at a common reference year was found to be an important metric to assess potential greenwashing or poor ambition. In 14% of cases, targets were already achieved when company launched them.

Investigation of Sulfation of CaO and CaCO3 in Eutectic CaF2–CaCl2

To achieve deep cuts in greenhouse gas emissions from stationary point sources such as carbon intensive industry and fossil power generation, carbon capture and storage (CCS) will be a necessity. Carbon capture in molten salts (CCMS) is an emerging technology with high potential. In CCMS, the reversible reaction between calcium oxide (CaO) and carbon dioxide (CO2) to form calcium carbonate (CaCO3) is utilized, with the active substances being dissolved or partly dissolved in molten salts. CCMS has previously demonstrated promising properties for carbon capture with simulated flue gases on the laboratory scale. The next step in the technology development is to test the performance under more realistic gas compositions. In the present work, the focus is on sulfur dioxide (SO2) and oxygen (O2), a combination often coexisting with CO2 in flue gases from power production or industry. Experiments have been performed to investigate indirect sulfation of CaO and direct sulfation of CaCO3 in a eutectic mixture of calcium fluoride (CaF2) and calcium chloride (CaCl2) because it is not known whether these are thermodynamically favored in the molten state. Simulated flue gases containing 0.5 vol % SO2 and 3 vol % O2 have been used. In addition, combined capture experiments with 14 vol % CO2 and levels of SO2 up to 0.5 vol % have been performed. The composition of the outlet gas from the reactor was analyzed by Fourier transform infrared spectroscopy. The results indicate that both direct and indirect sulfation occur and that carbon capture is only slightly, but not significantly, inhibited in accordance with the level of SO2 in the flue gas. Furthermore, it was shown that CO2 capture in molten salts is possible at temperatures above the decomposition temperature for CaCO3 in solid-state calcium looping. This is attributed to higher activities when the active substances are dissolved in molten salts. Based on experimental data and thermodynamic modeling, it was estimated that the ratio of activity coefficients for CaO and CaCO3 is between 5 and 6 when dissolved in eutectic CaF2–CaCl2.

Recent Advances in Small-Scale Carbon Capture Systems for Micro-Combined Heat and Power Applications

To restrict global warming and relieve climate change, the world economy requires to decarbonize and reduce carbon dioxide (CO2) emissions to net-zero by mid-century. Carbon capture and storage (CCS), and carbon capture and utilization (CCU), by which CO2 emissions are captured from sources such as fossil power generation and combustion processes, and further either reused or stored, are recognized worldwide as key technologies for global warming mitigation. This paper provides a review of the latest published literature on small-scale carbon capture (CC) systems as applied in micro combined heat and power cogeneration systems for use in buildings. Previous studies have investigated a variety of small- or micro-scale combined heat and power configurations defined by their prime mover for CC integration. These include the micro gas turbine, the hybrid micro gas turbine and solid-state fuel cell system, and the biomass-fired organic Rankine cycle, all of which have been coupled with a post-combustion, amine-based absorption plant. After these configurations are defined, their performance is discussed. Considerations for optimizing the overall system parameters are identified using the same sources. The paper considers optimization of modifications to the micro gas turbine cycles with exhaust gas recirculation, humidification, and more advanced energy integration for optimal use of waste heat. Related investigations are based largely on numerical studies, with some preliminary experimental work undertaken on the Turbec T100 micro gas turbine. A brief survey is presented of some additional topics, including storage and utilization options, commercially available CC technologies, and direct atmospheric capture. Based on the available literature, it was found that carbon capture for small-scale systems introduces a large energy penalty due to the low concentration of CO2 in exhaust gases. Further development is required to decrease the energy loss from CC for economic feasibility on a small scale. For the micro gas turbine, exhaust gas recirculation, selective gas recirculation, and humidification were shown to improve overall system economic performance and efficiency. However, the highest global efficiencies were achieved by leveraging turbine exhaust waste heat to reduce the thermal energy requirement for solvent regeneration in the CC plant during low- or zero-heating loads. It was shown that although humidification cycles improved micro gas turbine cycle efficiencies, this may not be the best option to improve global efficiency if turbine waste heat is properly leveraged based on heating demands. The biomass-organic Rankine cycle and hybrid micro gas turbine, and solid-state fuel cell systems with CC, are in early developmental stages and require more research to assess their feasibility. However, the hybrid micro gas turbine and solid-state fuel cell energy system with CC was shown numerically to reach high global efficiency (51.4% LHV). It was also shown that the biomass-fired organic Rankine cycle system could result in negative emissions when coupled with a CC plant. In terms of costs, it was found that utilization through enhanced oil recovery was a promising strategy to offset the cost of carbon capture. Direct atmospheric capture was determined to be less economically feasible than capture from concentrated point sources; however, it has the benefit of negative carbon emissions.

CO2 Injection Deformation Monitoring Based on UAV and InSAR Technology: A Case Study of Shizhuang Town, Shanxi Province, China

Carbon Capture, Utilization and Storage, also referred to as Carbon Capture, Utilization and Sequestration (CCUS), is one of the novel climate mitigation technologies by which CO2 emissions are captured from sources, such as fossil power generation and industrial processes, and further either reused or stored with more attention being paid on the utilization of captured CO2. In the whole CCUS process, the dominant migration pathway of CO2 after being injected underground becomes very important information to judge the possible storage status as well as one of the essential references for evaluating possible environmental affects. Interferometric Synthetic Aperture Radar (InSAR) technology, with its advantages of extensive coverage in surface deformation monitoring and all-weather traceability of the injection processes, has become one of the promising technologies frequently adopted in worldwide CCUS projects. In this study, taking the CCUS sequestration area in Shizhuang Town, Shanxi Province, China, as an example, unmanned aerial vehicle (UAV) photography measurement technology with a 3D surface model at a resolution of 5.3 cm was applied to extract the high-resolution digital elevation model (DEM) of the study site in coordination with InSAR technology to more clearly display the results of surface deformation monitoring of the CO2 injection area. A 2 km surface heaving dynamic processes before and after injection from June 2020 to July 2021 was obtained, and a CO2 migration pathway northeastward was observed, which was rather consistent with the monitoring results by logging and micro-seismic studies. Additionally, an integrated monitoring scheme, which will be the trend of monitoring in the future, is proposed in the discussion.

Techno-economic assessment of calcium and magnesium-based sorbents for post-combustion CO2 capture applied in fossil-fueled power plants

This work evaluates the most relevant techno-economic performances of calcium and magnesium-based sorbents used in high temperature solid looping cycles for post-combustion CO2 capture applied in fossil power generation. The evaluated power plants generate 1000 MW net electricity with 90% CO2 capture rate. As fuels, natural gas was assessed for combined cycle power plants since coal and lignite were assessed for super-critical power plants. As comparison benchmark systems, the correspondent plants with non-capture feature and with carbon capture using reactive gas–liquid absorption were also assessed. As the results show, both calcium and magnesium carbonate looping concepts applied in solid fossil fuel super-critical plants induce lower carbon capture energy penalty compared to the reactive gas–liquid absorption by about 1–2.2 net efficiency percentage points. The Calcium Looping (CaL) cycle shows higher net power efficiency than the Magnesium Looping (MgL) cycle by about 1–1.4 net percentage points. In case of natural gas combined cycle plants, the chemical absorption system has higher net power efficiency than CaL and MgL systems by about 4–6 percentage points. The key economic indicators (e.g., electricity production cost, CO2 capture costs etc.) show that both evaluated carbonate looping systems perform better than amine-based chemical scrubbing.

Recent developments in electricity generation by Microbial Fuel Cell using different substrates

The rise in electrical energy demand and environmental concern results in shifting the world’s focus towards sustainable energy sources. Over-reliance of conventional fossil fuel-based power generation can be combatted using new and potential technologies like Microbial Fuel cells (MFCs). Direct conversion of chemical energy to electrical energy by the application of the naturally found microorganisms, makes MFC more convenient source of energy generation. Despite having low power density, it has been able to grab the researcher’s attention due to the flexibility of usage of various organic substrates. This review discusses the various households and industrial waste substrate which has further potential to generate power. The various liquid and solid substrates have been analysed and summarized. The substrate used, power densities, reactor volumes and specific important features used by the researchers for the improved performance have been tabulated. In a higher number of researches, liquid substrates have been comparatively more used than that of the solid substrates. Ease of handling, storage and accessibility of the liquid waste could be one of the few reasons for it. Also, in this review, various components, and key factors for the experimental design of MFC has been discussed. Along with that losses associated with MFCs and its application is explored.