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The imperative to combat climate change necessitates the rapid implementation of technologically advanced, zero-emission renewable energy solutions, particularly considering the mounting energy demands and the pressing need to mitigate global warming. The proposed SOFC system, integrated with a modified Rankine Cycle and CCUS technology, offers a highly efficient, renewable system with a net-zero carbon footprint, utilising green biogas as an alternative. The fully integrated system at continuous operation does not require outside heat sources and, besides, its main electricity production can supply 231 households with hot sanitary water. A base case and sensitivity analysis of the system was conducted studying different operating parameters. The base case simulation, conducted at SOFC/reformer operating temperatures of 850 °C/650 °C and operating parameters S/C = 2.5, Uf = 0.70 Ua = 0.1806, yielded an overall efficiency of 71.64%, with a 67.70% electrical efficiency. Further simulations demonstrated that a 1.60% and 1.53% increase in the overall and electrical efficiencies of the proposed alternative, respectively, would be achieved at SOFC/reformer operating temperatures of 950 °C/650 °C. The simulated hybrid system represents a competitive installation in the renewable energy market, which offers a viable and sustainable alternative to traditional forms of energy generation. [ABSTRACT FROM AUTHOR]

The use of alternative fuels remains an important factor in solving the problem of reducing harmful substances caused by vehicles and decarbonising transport. It is also important to ensure the energy efficiency of vehicle power plants when using different fuels at a sufficient level. The article presents the results of theoretical and experimental studies of the conversion of diesel engine to alternative fuels with hydrogen admixtures. Methanol is considered as an alternative fuel which is a cheaper alternative to commercial diesel fuel. The chemical essence of improving the calorific value of alternative methanol fuel was investigated. Studies showed that the energy effect of burning an alternative mixture with hydrogen additives exceeds the effect of burning the same amount of methanol fuel. The increase in combustion energy and engine power is achieved as a result of heat from efficient use of the engine exhaust gases and chemical conversion of methanol. An experimental installation was created to study the work of a converted diesel engine on hydrogen–methanol mixtures and thermochemical regeneration processes. Experimental studies of the energy and environmental parameters of diesel engine converted to work on an alternative fuel with hydrogen admixtures have shown that engine power increases by 10–14% and emissions of harmful substances decrease. [ABSTRACT FROM AUTHOR]

The use of alternative fuels remains an important factor in solving the problem of reducing harmful substances caused by vehicles and decarbonising transport. It is also important to ensure the energy efficiency of vehicle power plants when using different fuels at a sufficient level. The article presents the results of theoretical and experimental studies of the conversion of diesel engine to alternative fuels with hydrogen admixtures. Methanol is considered as an alternative fuel which is a cheaper alternative to commercial diesel fuel. The chemical essence of improving the calorific value of alternative methanol fuel was investigated. Studies showed that the energy effect of burning an alternative mixture with hydrogen additives exceeds the effect of burning the same amount of methanol fuel. The increase in combustion energy and engine power is achieved as a result of heat from efficient use of the engine exhaust gases and chemical conversion of methanol. An experimental installation was created to study the work of a converted diesel engine on hydrogen–methanol mixtures and thermochemical regeneration processes. Experimental studies of the energy and environmental parameters of diesel engine converted to work on an alternative fuel with hydrogen admixtures have shown that engine power increases by 10–14% and emissions of harmful substances decrease.

The ambitious climate targets of the European Union emphasise the necessity to reduce carbon dioxide emissions in the building sector. Therefore, various sustainable heat sources should be used in existing district heating systems to cover the heat demands of buildings. However, integrating on-site heat sources into large existing district heating networks could be challenging due to temperature or capacity limitations since such large district heating systems are often supplied by large fossil-based heating plants. Most sustainable heat sources that should be utilised in district heating systems differ in their geographical locations or have limited heat capacities and, therefore, cannot easily replace conventional heating plants. The resulting difficulty of integrating limited heat sources into large district heating networks could be tackled by separating the existing network structure into two independent heat distribution networks. In this study, we present a developed framework that automatically recommends which network parts of an existing district heating system could be hydraulically separated in order to utilise a present heat source that is not yet in use. In this way, a second, standalone district heating system, supplied by the utilised heat source, could be established. The framework applies a community detection algorithm to the existing district heating network to first identify communities in the structure. Neighbouring communities are aggregated to larger network areas, taking into account that these areas could be supplied with the available amount of heat. These network areas are classified as possible areas for separation if the shortest connection path to the utilised heat source is within a certain distance. Subsequently, the found possibilities for network separation are simulated to test a feasible district heating operation and to evaluate the environmental and economic impacts. The presented framework is tested with a meshed and a spanning-tree network structure. Overall, the developed framework presents an approach to utilise present heat sources in separated network structures by automatically identifying, testing and evaluating possible network separations. [ABSTRACT FROM AUTHOR]

Energy from woody biomass is expected to revitalise industry in Japan and induce job creation in the region. Woody biomass power plants have been rapidly constructed all over the country after the Feed-in Tariff scheme began. However, there are increasing cases of the destruction of natural ecosystems and landscapes to fulfil the growing demand for woody biomass. This study aims to describe the ideal energy utilisation of woody biomass from the viewpoint of preserving natural ecosystems. First, a conceptual model for the positive and negative impact of woody biomass energy utilisation on the natural ecosystem was organised. Next, an online survey to collect information and data on woody biomass power plants and heat utilisation facilities in Japan was conducted. In addition, the positive and negative impacts of using woody biomass on economic, environmental, and social systems as well as ecosystems were discussed. An online survey showed that the annual fuel usage of the woody biomass and number of employees increase with the scale of the power plant. Although annual expenses also increase, this might be a positive impact, because it can contribute to the economy and employment of the region based on the increase in the production value. In contrast, a negative impact is that some woody biomass power plants import biomass fuel. Importing the biomass fuel is reasonable from the viewpoint of fuel supply cost reduction and stable supply. However, there might be negative impact on the local natural ecosystem when the woody biomass is not appropriately utilised. [ABSTRACT FROM AUTHOR]

Professional laundry service is a leading solution for laundry maintenance in medical care, tourism, catering, and other commercial services. Industrial laundry is a significant worldwide sector with high energy demand. Industrial laundries use steam for heating the washing water, drying and ironing. Combined heat and power production is a promising and straightforward way to produce energy for the whole process. A gas microturbine (GMT) is a source of heat and electrical power with an efficiency of up to 90%. The laundry process development could be associated mainly with eliminating steam production and improving water utilisation. This paper provides an overview of the latest trends concerning the laundry process, introduces the grey-box model of the laundry process with GMT, evaluates several scenarios using the hot flue gas to operate the laundry machines, including their economy. GMT achieves the lowest operational cost and the highest primary energy savings (25.9%) within the evaluated scenarios, with an overall efficiency of 80.3%. The payback period for the greenfield project is 2.8 years and 5.8 for retrofit. It was found that GMT is an excellent source of electrical and thermal energy for industrial laundries utilising the hot flue gas for direct linen drying. [Display omitted] • Industrial laundry is an energy-demanding process with a great potential for process integration. • The concept of direct laundry drying with GMT flue gases was experimentally verified. • The GMT integration into the laundry brings high primary energy savings over 25%. • The GMT integration gives a payback period of 2.8 years for the greenfield project and 5.8 years for retrofit. [ABSTRACT FROM AUTHOR]

Abstract: Metal hydride (MH) thermal sorption compression is an efficient and reliable method allowing a conversion of energy from heat into a compressed hydrogen gas. The most important component of such a thermal engine – the metal hydride material itself – should possess several material features in order to achieve an efficient performance in the hydrogen compression. Apart from the hydrogen storage characteristics important for every solid H storage material (e.g. gravimetric and volumetric efficiency of H storage, hydrogen sorption kinetics and effective thermal conductivity), the thermodynamics of the metal–hydrogen systems is of primary importance resulting in a temperature dependence of the absorption/desorption pressures). Several specific features should be optimised to govern the performance of the MH-compressors including synchronisation of the pressure plateaus for multi-stage compressors, reduction of slope of the isotherms and hysteresis, increase of cycling stability and life time, together with challenges in system design associated with volume expansion of the metal matrix during the hydrogenation. The present review summarises numerous papers and patent literature dealing with MH hydrogen compression technology. The review considers (a) fundamental aspects of materials development with a focus on structure and phase equilibria in the metal–hydrogen systems suitable for the hydrogen compression; and (b) applied aspects, including their consideration from the applied thermodynamic viewpoint, system design features and performances of the metal hydride compressors and major applications. [Copyright &y& Elsevier]

The biogas generated in biogas plants offers significant potential for the production of energy from renewable energy sources. The number biogas plants in the Czech Republic is expected to exceed one hundred in the near future. Substrates from agriculture, industry and municipal wastes are used for biogas production. Biogas plants usually use co-generation units to generate electricity and heat. Increased effectiveness can be achieved by using heat as a source of energy for producing renewable natural gas.

The aim of this study is to investigate the operation of biogas plants in advanced energy markets after energy crops become limited in their use and biogas plants exit subsidy schemes for electricity production. Continuous biogas combined heat and power production and sale of electricity on the day-ahead market could be a viable operation strategy only in the case of low-cost substrates. When the break-even cost of electricity production in biogas power plants reaches 100 €/MWh el , selling electricity on the day-ahead market does not create profit. The study shown that a more profitable operation strategy involves coupling biogas power plant operation on the electricity balancing market with biomethane production or combining a small-scale sugar beet processing facility with a biogas upgrading plant to cover heat demand for sugar beet processing. Techno-economic analysis showed that the viability of both alternative operation strategies is severely impacted by the selling price of biomethane. In the given market conditions, a selling price of biomethane below 50 €/MWh is not viable for a biogas plant. The model developed could be used as a guideline for biogas plant operators on how to proceed after significant changes appear in both biogas production and biogas utilisation. • The operation of a biogas plant in advanced energy markets was studied. • Low-cost substrates become significant once a biogas plant exits subsidy schemes. • Biogas plants gain profit while operating on the electricity balancing market. • The biomethane selling price has a significant impact on the project's viability. [ABSTRACT FROM AUTHOR]