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Nytillverkade småskaliga biobränslepannor måste uppfylla ekodesignkraven senast år 2020. I en marknadsundersökning från 2014 klarade ingen av 11 testade pelletspannor alla ställda krav, vilket tydligt visar på ett utvecklingsbehov. Föreliggande projekt har haft som syfte att panntillverkare och forskningsinstitut branschgemensamt ska bemöta de förbränningstekniska utmaningar som tillverkarna står inför. För pelletspannor är den största utmaningen med ekodesigndirektivet att prestanda till största delen beräknas från drift vid partiell last (låg last). Tidigare har prestanda bara fastställts vid nominell last och designen optimerats därefter. I detta projekt har tester körts med två moderna pelletspannor som har olika typer av pelletsbrännare: en med horisontellt brännarrör och en med undermatad brännarkopp. Resultaten visar att tillräckligt god förbränning kunde upprätthållas vid partiell last med båda brännartyperna. Dock uppvisade rörbrännaren betydligt lägre emissioner vid partiell last, troligtvis beroende på att förbränningszonen i denna brännare är skyddad från värmestrålningsutbyte med kylande pannväggar. Ett ganska omfattande arbete lades ned på att förse koppbrännaren med en skyddande krage som skulle skydda förbränningszonen. Det resulterade dock inte in någon betydande förbättring, antagligen beroende på att tillförseln av sekundärluft inte blev optimal. Ett mer omfattande arbete krävs för att utveckla en optimal brännardesign av denna typ. För vedpannor är det en utmaning att klara ekodesigndirektivets NOx-krav på 200 mg/Nm³. En mängd temperaturmätningar i en vedpanna för villabruk resulterade i att termisk NOx-bildning kunde uteslutas. Pannan förseddes med ett system för rökgasåterföring, men det minskade inte NOx-emissionen. Därefter provades olika vedsorter. NOx-emissionen kunde minskas till att klara gränsvärdet med avbarkad björkved. Kemiska analyser visade att björkbarken innehöll 0,49% kväve jämfört med 0,09% i stamveden. Även granved gav låga NOx-emissioner, men det bränslet medförde ökade emissioner av CO och OGC. För att vedpannor ska klara kraven på CO, OGC och stoft krävs optimering med avseende på vedens slutförbränningsfas. I det skedet är emissionerna som högst, vilket beror på att värmeeffekten avtar och luftflödet tenderar att kyla ned rökgasen innan de brännbara gaserna brunnit ut. Den optiska partikelmätningen visade tydlig korrelation mellan stoft och CO i rökgasen. Om pannan uppfyller gränsvärdet för CO så finns goda chanser att även kravet på partiklar uppfylls. Verkningsgraden som anges i ekodesigndirektivet beräknas utgående från bränslets övre värmevärde. Dessutom subtraheras vissa förlustfaktorer. Detta innebär att pannan inte får ha några onödigt stora värmeförluster eller omotiverat hög elförbrukning för att klara satta krav. Mätningar visade att den största förlusten sker via värmen i rökgasen. Den näst största förlustposten är värmetransport från pannkroppen. För verkningsgraden ökar betydelsen av en välisolerad pannkropp vid partiell last. De två pelletspannor som användes inom projektet låg väl till för att kunna uppfylla ekodesigndirektivets krav på verkningsgrad. New domestic biofuel boilers must meet the Ecodesign Directive by 2020. In a market survey from 2014, none of 11 tested pellet boilers did meet all requirements, clearly indicating a developmental need. In the present project boiler manufacturers and research institutes have collaborated in response to the combustion engineering challenges. For pellet boilers, the biggest challenge with the Ecodesign Directive is that performance is largely calculated from partial load operation (low load). Previously, performance has only been determined at nominal load and the design has been optimized accordingly. In this project, tests have been run with two modern pellet boilers that have different types of pellet burner: one with horizontal burner tube and one with an underfeed burner cup. The results show that sufficient combustion performance could be maintained at partial load with both burner types. However, the tube burner exhibited significantly lower emissions at partial loads, probably due to the combustion zone in this burner being protected from heat radiation exchange with cooling boiler walls. A rather extensive work was laid down to provide the cup burner with a protective collar that would protect the combustion zone. However, it did not result in any significant improvement, probably because the supply of secondary air did not become optimal. A more extensive work is required to develop an optimal burner design of this type. For wood log boilers, it is a challenge to comply with the NOx requirements of the Ecodesign Directive of 200 mg / Nm³. A variety of temperature measurements in a wood log boiler resulted in the exclusion of thermal NOx formation. The boiler was fitted with a flue gas recirculation system, but it did not reduce the NOx emission. Then different varieties of wood fuels were tested. The NOx emission could be reduced to meet the requirement using barked birch wood. Chemical analyzes showed that the birch bark contained 0.49% nitrogen compared to 0.09% in the stock. Spruce logs also gave low NOx emissions, but that fuel resulted in increased CO and OGC emissions. For wood log boilers to meet the requirements for CO, OGC and dust, optimization is required under the wood's final combustion phase. At this stage, emissions are at its highest, due to the decreasing heat output while the airflow tends to cool down the flue gas faster than the combustible gases burn out. The optical particle measurement showed a clear correlation between dust and CO in the flue gas. If the boiler meets the CO limit, there are good chances that the requirement for particles also will be met. The efficiency specified in the Ecodesign Directive is calculated based on the fuel's higher heating value. In addition, some loss factors are subtracted. This implies that the boiler must not have unnecessarily large heat losses or excessive electricity consumption to meet the requirements. Measurements showed that the biggest loss occurs with the heat in the flue gas. The second largest loss is heat from the boiler body. For the efficiency, the importance of a well-insulated boiler body increases in the case of partial loads. The two pellet boilers used in the project were well suited to meet the eco-directive directive's efficiency requirements. Detta arbete har finansierats av Energimyndigheten inom Bränsleprogrammet omvandling och samfinansierats av de medverkande industriparterna Ariterm Sweden AB, Nibe AB och Värmebaronen AB.

ERA-NET Bioenergy is a network of national research and development programmes focusing on bioenergy which includes 14 funding organisations from 10 European countries: Austria, Denmark, Finland, France, Germany, Ireland, The Netherlands, Poland, Sweden and the United Kingdom. Its mission is to enhance the quality and cost-effectiveness of European bioenergy research programmes, through coordination and cooperation between EU Member States. The project Woodstoves2020 (Development of next generation and clean wood stoves) has been supported in the period between October 2009 and September 2012 by ERA-NET Bioenergy under 7th Joint Call for Research and Development of the ERA-NET Bioenergy from 2013. Today small-scale biomass combustion is one of the most relevant bioenergy applications. Driven by EU-wide and national measures to promote the utilisation of biomass for energy production, the European market for biomass based residential heating systems is expected to substantially increase by about 130% until 2020 (based on 2009). Regarding the installed units stoves show the highest and steadily increasing numbers in Europe. According to market studies performed within the EU FP7 project EU-UltraLowDust (Project No. 268189), in 2020 in Europe a potential for an annual installation of almost 2,200,000 stoves (logwood and pellet stoves) is forecasted. This additional potential for renewable energy production will of course contribute to a reduction of the EU greenhouse gas emissions. However, it is also well known that among the different residential biomass combustion technologies logwood stoves show the highest CO, OGC and fine particulate matter (PM) emissions. Against this background, the project Woodstoves2020 aims at the development of innovative measures and technologies in order to further reduce emissions from wood stoves, to increase their thermal efficiency and to expand their field of application from solely single room heating to central heating. The latter could especially be of relevance for future applications in low energy buildings. Accordingly, the detailed objectives of the project proposed can be structured as follows. Objectives related to emission reduction -Development and implementation of automated control systems for stoves as a feature of new stoves but also as retrofit units for existing models. Automated control systems can help to widely eliminate user induced operation errors and therefore have a huge potential for emission reduction.-Evaluation and test of new high-temperature catalysts specially adapted to wood stoves for efficient CO, OGC and soot emission reduction. Catalysts should be implemented in new stove concepts as a basis for an ultra-low emission operation which could be comparable to the emission level of automated small-scale boilers.-Evaluation and test of foam ceramic materials for efficient PM emission reduction.-Evaluation of the implementation of modern chimney draught regulators.Objectives related to increasing efficiency and new fields of application -Development and evaluation of efficient and novel heat storage options for stoves such as the application of PCM (phase change material) with high heat storage potential.-Investigations regarding efficient heat recovery from stoves (increase of efficiency by the implementation of heat storage units or measures to stabilise the draft or to reduce standing losses).Objectives related to the implementation and evaluation of the different measures -Test of the most promising concepts by performing test runs with prototypes.-Development of design guidelines for stove manufacturers based on the evaluation of the new technologies tested towards a clean stove technology 2020.-Development of guidelines for the implementation and retrofit of selected measures for old stoves.With the new technologies developed within the project an emission reduction between 50 and 80% and an increase of the efficiencies in a range above 90% shall be possible. If in future all newly installed wood stoves in Europe would be equipped with these new technologies, a PM emission reduction of 60 - 90% could be achieved. In order to reach these objectives, a consortium of 4 research organisations and 4 industrial partners from 4 European countries collaborated within Woodstoves2020 (see next page). This document summarises the outcomes of the investigations regarding the improvement of wood stoves by the application of automated control concepts as a primary measure for emission reduction. It should support stove manufacturers concerning the optimisation of their products and the development and design of new products with its recommendations which have been worked out based on scientific investigations as well as comprehensive test runs.

Die Vergleichbarkeit von Messergebnissen ist für eine weitere Datenverarbeitung und den darauf aufbauenden Auswertungen unumgänglich. Hier machen jedoch eine Vielzahl von Messverfahren und -methoden sowie fehlende Angaben zu den Messbedingungen und der Messgenauigkeit einen Vergleich unterschiedlicher Datensätze nahezu unmöglich. Dabei kann bereits durch die Angabe einiger wesentlicher Analyse- und Prozessparameter eine projektübergreifende Auswertung erfolgen und ein erheblicher Wissensgewinn generiert werden. Besonders dann, wenn kostenintensive Messkampagnen nur im begrenzten Umfang durchführbar sind, verbessern sich durch weitere Messdaten aus anderen Studien die Sicherheit und damit die Aussagekraft der Ergebnisse bei gleichzeitig geringem Mehraufwand. Die folgenden Ausführungen zu verschiedenen Messgeräten und -methoden zur Bestimmung von Permanentgaskonzentrationen sowie von Teergehalten im Produktgas von Holzvergasungsanlagen erheben nicht den Anspruch auf Vollständigkeit. Dennoch soll die exemplarische Darstellung allgemeine Hinweise für den Umgang mit Messdaten geben und die Nutzer von Messdaten für mögliche Probleme sensibilisieren, um Fehler bei der Auswertung zu minimieren. Damit ergänzt das Handbuch „Produktgasmessmethoden – Biomassevergasung“ neben den Methodensammlungen „Biogas“ und „Feinstaub“ die Arbeiten rund um die Methodenharmonisierung im Förderprogramm „Energetische Biomassenutzung“. Großer Dank für die unermüdliche Unterstützung gilt allen Projektpartnern, den Stadtwerken Rosenheim, der Burkhardt GmbH, der Spanner Re² GmbH und dem Projektteam der Programmbegleitung des Förderprogramms „Energetische Biomassenutzung“.

Worldwide, the use of transport fuel derived from biomass increased four-fold between 2003 and 2012. Mainly based on food resources, these conventional biofuels did not achieve the expected emission savings and contributed to higher prices for food commod - ities, especially maize and oilseeds. Advanced biofuels based on forest biomass are not yet being produced on a large scale, but are expected to have a better life-cycle emission profile than conventional biofuels. The pathways from feedstock to advanced biofuel are diverse in respect to capacity, technology and final product. Three promising conversion technologies are presented below: pyrolysis, biochemical conversion and gasification