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Biomass is widely acknowledged as a plentiful and easily accessible source of renewable energy. Unlike many other renewable sources, biomass offers a consistent and predictable power supply without significant concerns about energy and environmental impacts. When used as a fuel in polygeneration systems designed to produce multiple outputs such as electricity, heat, chemicals, and synthetic fuels, biomass greatly enhances overall system efficiency by minimizing energy losses. These systems gain further advantages when integrated in a decentralized manner with energy-intensive applications like buildings. This review article aims to shift the focus of readers from generic biomass-based systems to polygeneration systems tailored for specific applications, such as buildings. The overview will discuss various biomass resources, systematic approaches, technologies, successful case studies, potential benefits, and limitations of such systems integrated into real-life building applications. It also categorizes studies based on different conversion processes such as combustion, gasification, and anaerobic digestion, with combustion-based polygeneration systems being the most prevalent. The review also explores the use of standalone and hybrid biomass-based energy systems. Taking a multidisciplinary approach, the analysis considers energy, exergy, economic, and environmental perspectives. Parameters such as the primary energy savings (PES), exergy efficiency, simple payback (SPB) period, and CO2 emission reductions are commonly used in system analyses. The review underscores how polygeneration systems integrated into the building sector can enhance efficiency, resilience, and environmental sustainability. This synthesis aims to address current gaps, particularly in the domain of polygeneration systems connected with buildings, offering essential insights for researchers and specialists in the field. [ABSTRACT FROM AUTHOR]

This work aims to assess the effect of the operating parameters of the gasifying agent preheating temperature and equivalence ratio (ER) on the conversion of sewage sludge (SS) to syngas through gasification and combined heat and power (CHP) generation. A novel gasification model was simulated in Aspen Plus to represent a fixed-bed updraft gasifier to generate syngas from SS through an equilibrium approach restricted by temperature. The novelty of this work is that the model was developed by applying the gasifying agent preheating temperature as an operating variable instead of the gasification temperature. It was calibrated by using a set of experimental values and then validated by comparing the numerical results with the experimental outcomes related to nine different operating conditions of air preheating temperatures and ER. A good agreement between the simulation and experimental results was observed. The optimum gasification process parameters of the air preheating temperature and ER were predicted to be 150 °C and 0.2, respectively. The CHP generation potentiality of SS was assessed to be 2.54 kW/kg SS as dry solids (DS), of which 0.81 kW was electrical and the remainder was thermal power. The conversion of SS to CHP through the proposed treatment can reduce 0.59 kg CO₂/kg SS as DS emissions compared with that of natural gas combustion to generate a similar quantity of energy. [ABSTRACT FROM AUTHOR]