Emissions from Biomass Combustion (click here)
The article from the IEA Bioenergy Annual Report 2023 highlights the evolving role of biomass combustion as a cost-effective and locally sourced method for generating renewable heat and power. While it has long been used, modern advancements have significantly improved its efficiency, fuel flexibility, and emissions control. Biomass combustion now provides 89% of renewable heat globally, with most growth expected in industrial-scale applications. However, if outdated or poorly managed, it can emit harmful pollutants like particulate matter, CO, VOCs, NOx, and SOx, especially in densely populated areas. The article stresses the importance of advanced combustion and flue gas cleaning technologies to reduce these emissions. From a broader environmental perspective, biomass combustion can contribute to negative CO₂ emissions and mitigate nitrogen-related pollution when integrated with carbon capture technologies and viewed within the full biomass lifecycle.
Nitrogen flows in biomass combustion systems – A parametric scoping study aimed at optimising nitrogen flows in biomass combustion (click here)
The release of reactive nitrogen in the form of ammonia and nitrogen oxides from a wide variety of sources in society such as combustion processes and agricultural activities rises concerns due to its direct and indirect (as precursor) harm to environment and public health. This has led to several legal regulations aiming at reducing the release of reactive nitrogen to the environment. Only little research has been done so far on the quantification of reactive nitrogen flows along the whole biomass combustion cycle, including biomass growth and harvesting. This scoping study aims to identify the key parameters that influence nitrogen balances for a broad diversity of biomass combustion plants based on different technologies and fuels with varying nitrogen contents.
Design of Low Emission Wood Stoves – Technical guideline (click here)
Wood stoves are popular as a primary or complimentary heat source. However, unwanted byproducts are formed and emitted during combustion of wood logs. These emissions continue to be a concern for the environment and for public health. Correct operation and proper design are key to minimize harmful emissions. While both are equally important, the guidelines in this report focus on technological measures (e.g., stove design, flue gas cleaning and automatic control systems).
The future role of Thermal Biomass Power in renewable energy systems – a study of Germany (click here)
The global energy system is undergoing a shift from centralised, fossil-based sources to renewable energy, with wind and solar expected to dominate in many regions. However, their variable and non-dispatchable nature poses challenges for grid stability, especially during periods of low generation or mismatched demand. Bioenergy, as a dispatchable renewable source, offers a stabilising role in such systems. IEA Bioenergy Task 32 has explored the future role of thermal biomass power plants using a system-based approach, focusing on Germany as a thermal-dominated example. Modelling with the Balmorel tool revealed that current market conditions alone are insufficient to drive significant thermal biomass integration by 2040. Nonetheless, under favourable policy frameworks, biomass could provide base load electricity and district heating, while system flexibility would largely rely on hydropower, energy storage, and gas-fired units.
Bioenergy for heat – the Hot Cases (click here)
Heat accounts for roughly half of global final energy use, with fossil fuels currently supplying about 80% of that demand. However, many countries possess sufficient sustainable biomass resources to fully replace fossil fuels used for heating, offering the potential to decarbonise up to 40% of global energy end use. Task 32 of the IEA Bioenergy programme presented fifteen case studies demonstrating real-world applications of modern biomass-fired heating and co-generation systems. These transitions not only reduce CO₂ emissions but also enhance local economies by utilising regional waste and residues, creating jobs, and ensuring long-term access to affordable heat. Biomass thus emerges as a renewable, carbon-neutral energy source with strong socio-economic benefits.
Options for increased use of ash from biomass combustion and co-firing (click here)
This report presents an overview of current ash management practices from biomass (co)combustion across seven IEA Bioenergy Task 32 member countries—Austria, Canada, Denmark, Germany, Italy, the Netherlands, and Sweden—with additional input from South Africa and the United Kingdom. It highlights the diversity in national approaches and utilisation practices, compiled in a summary section and detailed in country-specific appendices. Despite the global relevance of ash management, few best practice guidelines exist, underscoring the need for improved international knowledge sharing and harmonisation, particularly in areas like forest application. The report aims to serve as a foundation for broader collaboration and standardisation efforts in sustainable ash utilisation.
Advanced Test Methods for Firewood Stoves (click here)
This report by Gabriel Reichert and Christoph Schmidl evaluates various global test methods for measuring emissions from woodstoves, focusing on how accurately they reflect real-life usage. It compares standard official type testing (oTT), field tests, and newer protocols like the beReal test, which aims to simulate actual stove operation more closely. Findings show that while firewood stove technology has improved over time, oTT results often overstate performance compared to real-world conditions. The beReal protocol demonstrated better alignment with field data, especially for CO and PM emissions, though thermal efficiency remains overestimated in lab settings. The study suggests that adopting real-life-oriented testing like beReal as a standard or quality label could drive further technological improvements and help consumers distinguish between high- and low-performing stoves. It also recommends continued research to refine such protocols and support more accurate emission inventories.
Techno-economic evaluation of selected decentralised CHP applications based on biomass combustion with steam turbine and ORC processes (click here)
This report evaluates the techno-economic performance of three biomass combustion-based combined heat and power (CHP) systems ranging from 130 kWe to 5.7 MWe, using real-life case studies to represent the most relevant small-scale technologies currently on the market. It compares the technologies in terms of their integration into heat supply systems, technical performance, and economic viability. The findings highlight the key conditions necessary for effective deployment and provide a solid foundation for future design, implementation, and optimisation of such systems, as well as for guiding further technological development.
Status overview of torrefaction technologies – A review of the commercialisation status of biomass torrefaction (click here)
This IEA Bioenergy Task 32 publication provides an update of the status of commercialisation of biomass torrefaction. It contains both a review of recent research efforts and an overview of the progress made in commercialisation of the technology.
Advanced characterisation methods for solid biomass fuels (click here)
This study has been performed in order to gain an overview about advanced biomass fuel characterisation techniques currently applied, to discuss the strengths and weaknesses of the different methods, their specific fields of application as well as to assess the suitability of the different methods for the investigation of new biomass fuels.
Status Report on District Heating Systems in IEA Countries (click here)
The study presents an evaluation of district heating systems in IEA countries based on characteristic parameters such as the annual heat losses, the linear heat density in MWh/(a m) (where 1 m refers to the length of the pipeline), and the connection load. Data are available and presented for Austria, Denmark, Finland, Germany, and Switzerland covering a total of 800 district heating systems. An additional assessment is performed for the case of Switzerland where detailed information on 52 systems was collected and evaluated.
Sensitivity of System Design on Heat Distribution Cost in District Heating (click here)
District heating (DH) offers interesting opportunities to use biomass and/or waste heat as an energy source for thermal heat and thus to replace decentralised fossil heating. On the other hand however, district heating induces additional cost and energy losses in the heat distribution. The present project introduces a sensitivity analysis for a virtual DH network with 1 MW heat output, a pipeline length of 1 km, and a heat consumption over 2000 annual full-load hours corresponding to a linear heat density of 2000 MWh per year and meter of pipeline length (MWh/m a).
Status overview of torrefaction technologies (click here)
This report aims to summarise the current status of development of torrefaction technologies including technical and economical aspects and the potential market application from the energy sector perspective. It is based on several recent public reports as well as research and market information from sources such as IEA Bioenergy workshops in 2011 and 2012, direct contacts with technology developers, university and institutional researchers.
Options for increased utilization of ash from biomass combustion and co-firing (click here)
The current study shows that the main reasons for this situation relate to environment, sustainability, low market volumes and differences and variations in ash quality. In addition, there are limitations in technical and regulatory regulations as well as logistics. Finally, there is a lack of awareness, knowledge and willingness of plant operators, potential end-users and authorities alike to improve utilization.
Factsheet on indirect cofiring (click here)
Indirect co-firing consists of the combustion of producer gas from biomass/waste gasification in coal-fired furnaces or lime kilns. Gasification can be thus considered a method for biomass pre-processing.
Review of models and tools for slagging and fouling prediction for biomass co-combustion (click here)
Options for high percentage biomass cofiring in new power plants (click here)
The focus of the workshop is to discuss new technologies for co-firing, and share the ideas with the audience. Therefore, a number of presentations have been prepared covering the field of new technologies.
Determination of the Efficiencies of Automatic Biomass Combustion Plants (click here)
The main objective of the present investigation is the evaluation and comparison of different methods for the determination of the efficiencies of automatic biomass combustion plants. For this purpose, detailed formulae for the combustion efficiency, the boiler efficiency and the annual plant efficiency are described and methods for direct and indirect determination are identified. Furthermore, a calculation of the uncertainties is carried out for each method.
Biomass-coal Co-combustion: Opportunity for Affordable Renewable Energy (click here)
This investigation explores the reasons for and technical challenges associated with co-combustion of biomass and coal in boilers designed for coal (mainly pulverized coal) combustion.
Techno-economic evaluation of selected decentralised CHP applications based on biomass combustion in IEA Partner countries final report (click here)
The main objectives of the project were to gain an overview of technological developments and demonstration activities regarding small-scale biomass CHP systems based on biomass combustion and to perform technological and economic evaluations of innovative small-scale biomass CHP technologies.
Basic information regarding decentralised CHP plants based on biomass combustion in IEA partner countries (click here)
Evaluation of Biomass Combustion based Energy Systems by Cumulative Energy Demand and Energy Yield Coefficient (click here)
The study presents a method for a comparison of different energy systems with respect to the overall energy yield during the life cycle. For this purpose, the Cumulative Energy Demand (CED) based on primary energy and the Energy Yield Factor (EYC) are introduced and determined for the following scenarios: Log wood, wood chips, and wood pellets for residential heating and – except for log wood – also for district heating. As an alternative to heat production, power production via combustion and utilisation of the electricity for decentralised heat pumps is also regarded. The scenario for power production is valid for both, dedicated power production with biomass or co-firing of biomass. The main difference between these two applications is respected with a variation of the net electrical efficiency.
Biomass Cofiring Workshop 5 of the 12th European Conference on Biomass for Energy, Industry and Climate Protection (click here)
As part of the 12th European Conference on Biomass for Energy and Industry held on 17-21 June 2002 in Amsterdam, a workshop on biomass cofiring was organised by IEA Bioenergy Task 32 (Biomass Combustion and Cofiring), Task 33 (Biomass Gasification) and EUBIONET (the European Bioenergy Network). This report shows the overhead sheets that were presented.
Workshop Biomass Combustion Modelling (click here)
Prior to the organisation of the Sevilla modelling workshop, a questionnaire was send out amongst 59 R&D organisations, manufacturers etc. in the member countries to evaluate the contents and status of ongoing modelling projects and programmes. 38 questionnaires on modelling projects were returned to IEA. The results of the questionnaires were evaluated and shared with the respondents. A summary is attached in annex 2; the full report is available through IEA Bioenergy Task 19.
Addressing the Constraints for Successful Replication of Demonstrated Technologies for Co-combustion of Biomass/Waste (click here)
The final seminar of the EU Thermie B project “Addressing the constraints for successful replication of demonstrated technologies for co-combustion of biomass/waste” was held at the 1 st World Conference and Exhibition on Biomass for Energy and Industry and was supported by the IEA Coal Combustion Science Group and the IEA Bioenergy Task 19: Biomass Combustion. Over 130 participants attended the seminar which incorporated both the results of the two workshops held earlier in the EU-project as well as co-firing experiences and research activities in the USA.
Exploratory investigation into the possibilities of processing ash produced in the combustion of reject wood (click here)
The objective of this study is to obtain an overall insight into the possibilities of beneficially using the ash residue from reject wood combustion within the applicable environmental protection criteria.