• Energy Research
• Open Access close
• GB close
• ES close

Biomass plays an important role in the world primary energy supplies, currently providing ∼14% of the world's primary energy needs and being the fourth largest contributor following coal, oil and natural gas. Over the past decade, domestic biomass heating has received more governmental and public supports than ever before in many developed countries, such as the UK. Although biomass combustion releases some combustion pollutants, biomass is renewable and produces little net CO 2 emissions to the atmosphere. Owing to the low sulphur and low nitrogen contents of many biomass materials, substituting biomass for fossil fuels, particularly coal, can reduce SO x and NO x emissions. This study investigated flue gas emissions, particularly carbon monoxide and nitrogen oxides, of a domestic biomass boiler under various operating conditions. The biomass boiler used in this study satisfies the current EU regulation (EN 303-05) on emissions of domestic biomass boilers. Emissions of the boiler had been measured not only under normal combustion conditions, but also under 'idle' combustion conditions when the boiler was not in but was ready for full operation. The experimental results are analysed and presented in this paper. Copyright The Author 2010. Published by Oxford University Press. All rights reserved. For Permissions, please email: journals.permissions@oxfordjournals.org, Oxford University Press.

Biomass plays an important role in the world primary energy supplies, currently providing ∼14% of the world's primary energy needs and being the fourth largest contributor following coal, oil and natural gas. Over the past decade, domestic biomass heating has received more governmental and public supports than ever before in many developed countries, such as the UK. Although biomass combustion releases some combustion pollutants, biomass is renewable and produces little net CO 2 emissions to the atmosphere. Owing to the low sulphur and low nitrogen contents of many biomass materials, substituting biomass for fossil fuels, particularly coal, can reduce SO x and NO x emissions. This study investigated flue gas emissions, particularly carbon monoxide and nitrogen oxides, of a domestic biomass boiler under various operating conditions. The biomass boiler used in this study satisfies the current EU regulation (EN 303-05) on emissions of domestic biomass boilers. Emissions of the boiler had been measured not only under normal combustion conditions, but also under 'idle' combustion conditions when the boiler was not in but was ready for full operation. The experimental results are analysed and presented in this paper. Copyright The Author 2010. Published by Oxford University Press. All rights reserved. For Permissions, please email: journals.permissions@oxfordjournals.org, Oxford University Press.

Considering recent environmental regulations, the need to adapt domestic biomass combustion systems to models that generate less emissions has gained relative importance. The present research proposes an analysis of the bed cooling effects on emission patterns, specifically focusing on the concentration, typology and morphological aspects of the released particles. The study was carried out by comparing the behaviour of a small-scale pilot plant with air stratification, with and without bed cooling. The results revealed an optimal behaviour of the facility with distributions of 30% primary-70% secondary air, accompanied by a significant decrease in emissions due to the reduction in the operating temperatures. More than 75% of the particles were retained in the bed on the cooled surfaces due to the effect of the prominent temperature gradient that was produced. Among the types of emitted particles (mostly with sizes below 0.1 μm), the presence of partial biomass degradation remnants was observed, representing three-quarters of the total collected matter. To a lesser extent, the presence of carbonaceous agglomerates was detected and usually in very compact clusters; however, in cases of high primary air supply, large amounts of immature soot were observed. Agencia Estatal de Investigación | Ref. RTI2018-100765-B-I00

Considering recent environmental regulations, the need to adapt domestic biomass combustion systems to models that generate less emissions has gained relative importance. The present research proposes an analysis of the bed cooling effects on emission patterns, specifically focusing on the concentration, typology and morphological aspects of the released particles. The study was carried out by comparing the behaviour of a small-scale pilot plant with air stratification, with and without bed cooling. The results revealed an optimal behaviour of the facility with distributions of 30% primary-70% secondary air, accompanied by a significant decrease in emissions due to the reduction in the operating temperatures. More than 75% of the particles were retained in the bed on the cooled surfaces due to the effect of the prominent temperature gradient that was produced. Among the types of emitted particles (mostly with sizes below 0.1 μm), the presence of partial biomass degradation remnants was observed, representing three-quarters of the total collected matter. To a lesser extent, the presence of carbonaceous agglomerates was detected and usually in very compact clusters; however, in cases of high primary air supply, large amounts of immature soot were observed. Agencia Estatal de Investigación | Ref. RTI2018-100765-B-I00

Analyzing television discourse during 2021 through a statistical sample of records extracted from TV networks, the configuration that, in the pandemic, adjusted the dialectical mediation between television communication and cognitive capital available for resilience to Climate Change is revealed. This study originates from reports that in collaboration with ECODES and funding from the Ministry for the Ecological Transition and the Demographic Challenge, carried out by the Media Communication Observatory on Climate Change at its headquarters of the MDCS Research Group of the UCM. The analysis revealed how the causes, impacts, mitigation, and adaptation projects to the effects of climate change were communicated, and the identity of those who speak and/or are referred to. The discursive hegemony of mediators (journalists) and politicians is confirmed, to the detriment of scientists, and improved communication for resilience to climate change is promoted. ; Analizado el discurso televisivo durante 2021 a través de una muestra representativa de registros extraídos de cadenas de TV, se revela la configuración que, en la pandemia, ajustó la mediación dialéctica entre comunicación televisiva y capital cognitivo disponible para la resiliencia ante el Cambio Climático. Este estudio se origina en informes que en colaboración con ECODES y financiación del Ministerio para la Transición Ecológica y el Reto Demográfico, realiza el Observatorio de la Comunicación Mediática del Cambio Climático en su sede del Grupo de Investigación MDCS, de la UCM. El análisis desveló cómo se comunicaron las causas, los impactos, los proyectos de mitigación y adaptación ante los efectos del cambio climático, y la identidad de quienes toman la palabra y/o son aludidos. Se confirma la hegemonía discursiva de mediadores (periodistas) y políticos, en detrimento de los científicos, y se promueve mejorar la comunicación para la resiliencia ante el cambio climático.

Analyzing television discourse during 2021 through a statistical sample of records extracted from TV networks, the configuration that, in the pandemic, adjusted the dialectical mediation between television communication and cognitive capital available for resilience to Climate Change is revealed. This study originates from reports that in collaboration with ECODES and funding from the Ministry for the Ecological Transition and the Demographic Challenge, carried out by the Media Communication Observatory on Climate Change at its headquarters of the MDCS Research Group of the UCM. The analysis revealed how the causes, impacts, mitigation, and adaptation projects to the effects of climate change were communicated, and the identity of those who speak and/or are referred to. The discursive hegemony of mediators (journalists) and politicians is confirmed, to the detriment of scientists, and improved communication for resilience to climate change is promoted. ; Analizado el discurso televisivo durante 2021 a través de una muestra representativa de registros extraídos de cadenas de TV, se revela la configuración que, en la pandemia, ajustó la mediación dialéctica entre comunicación televisiva y capital cognitivo disponible para la resiliencia ante el Cambio Climático. Este estudio se origina en informes que en colaboración con ECODES y financiación del Ministerio para la Transición Ecológica y el Reto Demográfico, realiza el Observatorio de la Comunicación Mediática del Cambio Climático en su sede del Grupo de Investigación MDCS, de la UCM. El análisis desveló cómo se comunicaron las causas, los impactos, los proyectos de mitigación y adaptación ante los efectos del cambio climático, y la identidad de quienes toman la palabra y/o son aludidos. Se confirma la hegemonía discursiva de mediadores (periodistas) y políticos, en detrimento de los científicos, y se promueve mejorar la comunicación para la resiliencia ante el cambio climático.

There are different monitoring procedures in wind farms with two main objectives: (i) to improve energy production by the capability of the national electrical network and (ii) to reduce the stooped hours due to preventive and or corrective maintenance activities. In this sense, different sensors are employed to sample in real-time the working conditions of equipment, the electrical production and the weather conditions. Despite this, just the anemometer measurement can be related to the more important errors of interruption of power regulation and anemometer errors. Both errors are related to gusty winds and contribute to more than 33% of the cost of a wind farm. The present paper reports some mathematical relations between weather and maintenance but there are no extreme values of each variable that let us predict a near failure and its corresponding loss of working hours. To achieve this, statistical analysis identifies the relation between weather variables and errors and different models are obtained. What is more, due to the difficulty and economic implications involving the implementation of complex algorithms and techniques of artificial intelligence, it is still a challenge to optimize this process. Finally, the obtained results show a particular case study that can be extrapolated to other wind farms after different case studies to adjust the model to different weather regions, and serve as a useful tool for weather maintenance.

There are different monitoring procedures in wind farms with two main objectives: (i) to improve energy production by the capability of the national electrical network and (ii) to reduce the stooped hours due to preventive and or corrective maintenance activities. In this sense, different sensors are employed to sample in real-time the working conditions of equipment, the electrical production and the weather conditions. Despite this, just the anemometer measurement can be related to the more important errors of interruption of power regulation and anemometer errors. Both errors are related to gusty winds and contribute to more than 33% of the cost of a wind farm. The present paper reports some mathematical relations between weather and maintenance but there are no extreme values of each variable that let us predict a near failure and its corresponding loss of working hours. To achieve this, statistical analysis identifies the relation between weather variables and errors and different models are obtained. What is more, due to the difficulty and economic implications involving the implementation of complex algorithms and techniques of artificial intelligence, it is still a challenge to optimize this process. Finally, the obtained results show a particular case study that can be extrapolated to other wind farms after different case studies to adjust the model to different weather regions, and serve as a useful tool for weather maintenance.