Browsing by Subject "bioenergy"

Sort by: Order: Results:

Now showing items 1-14 of 14
  • Vuorinne, Ilja Elias; Heiskanen, Janne; Pellikka, Petri (2021)
    Biomass is a principal variable in crop monitoring and management and in assessing carbon cycling. Remote sensing combined with field measurements can be used to estimate biomass over large areas. This study assessed leaf biomass of Agave sisalana (sisal), a perennial crop whose leaves are grown for fibre production in tropical and subtropical regions. Furthermore, the residue from fibre production can be used to produce bioenergy through anaerobic digestion. First, biomass was estimated for 58 field plots using an allometric approach. Then, Sentinel-2 multispectral satellite imagery was used to model biomass in an 8851-ha plantation in semi-arid south-eastern Kenya. Generalised Additive Models were employed to explore how well biomass was explained by various spectral vegetation indices (VIs). The highest performance (explained deviance = 76%, RMSE = 5.15 Mg ha−1) was achieved with ratio and normalised difference VIs based on the green (R560), red-edge (R740 and R783), and near-infrared (R865) spectral bands. Heterogeneity of ground vegetation and resulting background effects seemed to limit model performance. The best performing VI (R740/R783) was used to predict plantation biomass that ranged from 0 to 46.7 Mg ha−1 (mean biomass 10.6 Mg ha−1). The modelling showed that multispectral data are suitable for assessing sisal leaf biomass at the plantation level and in individual blocks. Although these results demonstrate the value of Sentinel-2 red-edge bands at 20-m resolution, the difference from the best model based on green and near-infrared bands at 10-m resolution was rather small.
  • Joas, Markus (Helsingfors universitet, 2014)
    The Finnish forest industries are going through heavy adjustments as especially the western world is moving towards a more digitalized model where the amount of paper and pulp consumed is diminishing. It is obvious that the whole industry is in need for new solutions. These new solutions and innovations can be found from the field of bioenergy. Finland is rich with forest-based raw material which can provide a long-term and local source of energy. In the future this will be of primary importance as the prices of the non-renewable energy sources will climb higher as the deposits of the fossil fuels dry up. The usage of the renewable energy sources are also very important in order to prevent the global climate change and to achieve the goals regulated for Finland in the Kyoto Protocol and the European RES-E directive. This Master’s Thesis takes a look at the current state and the future trends of the Finnish wood pellet industries. The domestic wood-based pellet industries are studied with a concise literature review and a SWOT analysis based on the earlier literature. The analysis is linked to the future expectations and current retailer perspectives with a survey conducted between June and October 2013. The sample consists of 39 low, medium and high sales volume wood pellet manufacturers and retailers whom mostly do only domestic pellet trading business. Most of the strengths of the domestic wood-based pellet industries are related to different kinds of ecological aspects or different kinds of raw material related issues. In the future especially the prices of the raw materials, prices of other energy sources and prices of the end-product will be in a crucial role. Most of the survey participants underlined the significance of the governmental acts concerning the future of the whole business in Finland: a favorable taxing policy and different subsidies can make Finland truly a greener economy but this have not happened yet, much due to the unfavorable domestic politics. According to the survey respondents, in the future the demand of wood-based pellet services, especially tailored and ready-to-use services from maintenance to deliveries are going to increase.
  • Helenius, Juha; Hagolani-Albov, Sophia; Koppelmäki, Kari (2020)
    Critics of modern food systems argue for the need to shift from a consolidated and concentrated, often monoculture based agro-industrial model toward diversified, post-fossil, and nutrient recycling food systems. The abundance of acute and obvious environmental problems in the agricultural sub-systems of the broader food system(s) have resulted in a focus on technological and natural scientific research into "solving" these point of production problems. Yet, there are many facets of food systems that are vital to sustainability which are not addressed even if the environmental problems were solved. In this article, we argue for agroecological symbiosis (AES) as a generic arrangement for re-configuring the primary production of food in agriculture, the processing of food, and development of a food community to work toward system-level sustainability. The guiding principle of this concept was the desire to base farming and food processing on renewable bioenergy, to close nutrient cycles, to break away from the consolidated food chain, to be more transparent and connected with consumers, and to revitalize the rural spaces where farms generally operate. Through a consistent and robust collaboration and co-creative process with transdisciplinary actors, ranging from food producers, and processers to policy actors, we designed a food system model based on networks of AES (NAES). The NAES would form place-based food networks, replacing the consolidated commodity chains. The NAES supports sustainable interactions from a biophysical and socio-cultural perspective. In this paper, we explain the AES concept, give an overview of the process of co-creating the pilot AES, and a proposal for the extension of the AES, as NAES, to create sustainable food systems. Overall, we conclude that the AES model holds potential for creating place-based food systems that further the sustainability agenda.
  • Epie, Kenedy E.; Artigas, Olga M.; Santanen, Arja; Mäkelä, Pirjo S. A.; Stoddard, Frederick L. (2018)
    The biomass potential of eight high yielding maize cultivars was studied in the sub-boreal climate of southern Finland. The effects of harvest date on lignin and sugar production, biomass yield, mineral element composition, bioenergy potential and soil nutrient management were determined in two years. The eight maize cultivars produced 17.6-33.3 t ha(-1) of biomass. The ear fraction contained 50-60% of the biomass, and ash and mineral element composition of the plant fractions were significantly different (p <0.001), with more ash, Ca and S in the above-ear fractions of the plants than in the mid-stalk portions, whereas the C:N ratio was highest in the lower stalk. Cultivars with less lignin content produced more fermetable sugars. Despite the relatively cool growing conditions and short season of the sub-boreal region, maize has potential for use as biomass, for biofuel or other uses. The crop can be fractioned into ear and stalk, with the lower 20 cm of stalk left in the field to maintain soil organic matter content.
  • Huisman-Dellago, David (Helsingin yliopisto, 2020)
    Dairy farms account for a large portion of the greenhouse gas emissions in the planet. Since cow manure provides a good medium for anaerobic digestion, this study analyzes the economic feasibility of installing a biogas plant adjacent to a 200-cow farm in Finland. The farms in this study produce only cow manure and grass silage to feed the digester. This paper focuses in comparing different scenarios such as electricity production for farm needs and the production of biofuels such as compressed biomethane as an additional business activity. After designing the farm economic model and the biogas installation, we provide an economic analysis of each scenario. The first one shows that it is not feasible to run the biogas business model based only on electricity savings for the farm. The second one proves that additional revenue streams such as biofuel production can revitalize and strengthen the financial model of the plant. Then, the sensitivity and reliability of the model is discussed by providing reasons (i.e. Finnish electricity tariff system) for the outcome of the results. The model reinforces the idea that farms must base their biogas business model on alternative side-streams and do not rely on energy production only. For further research, it is recommended that real life farm business models are incorporated as input data and a proven plant and CHP engine energy balance is secured.
  • Toivio, Matti (Helsingfors universitet, 2011)
    Finnish forest industry is in the middle of a radical change. Deepening recession and the falling demand of woodworking industry´s traditional products have forced also sawmilling industry to find new and more fertile solutions to improve their operational preconditions. In recent years, the role of bioenergy production has often been highlighted as a part of sawmills´ business repertoire. Sawmilling produces naturally a lot of by-products (e.g. bark, sawdust, chips) which could be exploited more effectively in energy production, and this would bring more incomes or maybe even create new business opportunities for sawmills. Production of bioenergy is also supported by government´s climate and energy policies favouring renewable energy sources, public financial subsidies, and soaring prices of fossil fuels. Also the decreasing production of domestic pulp and paper industry releases a fair amount of sawmills´ by-products for other uses. However, bioenergy production as a part of sawmills´ by-product utilization has been so far researched very little from a managerial point of view. The purpose of this study was to explore the relative significance of the main bioenergy-related processes, resources and factors at Finnish independent industrial sawmills including partnerships, cooperation, customers relationships and investments, and also the future perspectives of bioenergy business at these sawmills with the help of two resource-based approaches (resource-based view, natural-resource-based view). Data of the study comprised of secondary data (e.g. literature), and primary data which was attracted from interviews directed to sawmill managers (or equivalent persons in charge of decisions regarding bioenergy production at sawmill). While a literature review and the Delphi method with two questionnaires were utilized as the methods of the study. According to the results of the study, the most significant processes related to the value chain of bioenergy business are connected to raw material availability and procurement, and customer relationships management. In addition to raw material and services, the most significant resources included factory and machinery, personnel, collaboration, and geographic location. Long-term cooperation deals were clearly valued as the most significant form of collaboration, and especially in processes connected to raw material procurement. Study results also revealed that factors related to demand, subsidies and prices had highest importance in connection with sawmills´ future bioenergy business. However, majority of the respondents required that certain preconditions connected to the above-mentioned factors should be fulfilled before they will continue their bioenergy-related investments. Generally, the answers showed a wide divergence of opinions among the respondents which may refer to sawmills´ different emphases and expectations concerning bioenergy. In other words, bioenergy is still perceived as a quite novel and risky area of business at Finnish independent industrial sawmills. These results indicate that the massive expansion of bioenergy business at private sawmills in Finland is not a self-evident truth. The blocking barriers seem to be connected mainly to demand of bioenergy and money. Respondents´ answers disseminated a growing dissatisfaction towards the policies of authorities, which don´t treat equally sawmill-based bioenergy compared to other forms of bioenergy. This proposition was boiled down in a sawmill manager´s comment: “There is a lot of bioenergy available, if they just want to make use of it.” It seems that the positive effects of government´s policies favouring the renewables are not taking effect at private sawmills. However, as there anyway seems to be a lot of potential connected to emerging bioenergy business at Finnish independent industrial sawmills, there is also a clear need for more profound future studies over this topic.
  • Osborne, Nathaniel (Helsingfors universitet, 2013)
    Increasing fossil fuel prices, concerns about domestic energy security and demand for environmentally friendly, low carbon energy sources are renewing interest in using wood for energy. State and federal government have responded to increased interest with legislation that promotes renewable energy. Logging residues important role as an energy feedstock and environmental component has been a central topic of discussion for the growing forest energy sector in the United States. Over the last five years, I have studied forest harvest residues in the southern United States and abroad. My principle research focus has been the rapid inventory of residues, determination of their stocking and the identification of factors influencing that stocking. This composite report provides a detailed account of three studies based on five years of data in North Carolina, Georgia and southern Sweden. Provided in the report is an adapted method to inventory scattered and piled forest harvest residues, the relationship of harvest residues and harvest systems and a wood energy recovery rate for low end biomass within intensively managed loblolly pine forests. The goal of providing these studies is to contribute useful observations to the ongoing discussion about forest harvest residues and to provide a sampling framework others can employ to do similar studies.
  • Santangeli, Andrea; Toivonen, Tuuli; Pouzols, Federico Montesino; Pogson, Mark; Hastings, Astley; Smith, Pete; Moilanen, Atte (2016)
    Reliance on fossil fuels is causing unprecedented climate change and is accelerating environmental degradation and global biodiversity loss. Together, climate change and biodiversity loss, if not averted urgently, may inflict severe damage on ecosystem processes, functions and services that support the welfare of modern societies. Increasing renewable energy deployment and expanding the current protected area network represent key solutions to these challenges, but conflicts may arise over the use of limited land for energy production as opposed to biodiversity conservation. Here, we compare recently identified core areas for the expansion of the global protected area network with the renewable energy potential available from land-based solar photovoltaic, wind energy and bioenergy (in the form of Miscanthusxgiganteus). We show that these energy sources have very different biodiversity impacts and net energy contributions. The extent of risks and opportunities deriving from renewable energy development is highly dependent on the type of renewable source harvested, the restrictions imposed on energy harvest and the region considered, with Central America appearing at particularly high potential risk from renewable energy expansion. Without restrictions on power generation due to factors such as production and transport costs, we show that bioenergy production is a major potential threat to biodiversity, while the potential impact of wind and solar appears smaller than that of bioenergy. However, these differences become reduced when energy potential is restricted by external factors including local energy demand. Overall, we found that areas of opportunity for developing solar and wind energy with little harm to biodiversity could exist in several regions of the world, with the magnitude of potential impact being particularly dependent on restrictions imposed by local energy demand. The evidence provided here helps guide sustainable development of renewable energy and contributes to the targeting of global efforts in climate mitigation and biodiversity conservation.
  • Muhonen, Olli (Helsingfors universitet, 2012)
    Forest energy harvesting has increased significantly in recent years. The extraction of forest energy is usually done with conventional forwarders. The productivity of extraction work is, however, quite poor due to a low material density, which results in a small load size. The objective of the study was to increase the productivity of forest energy extraction via solutions that increase the load size. The first method that was studied involved widening the load space hydraulically. The other solution was based on compressing the load with hydraulically tiltable stakes. The study was conducted as a development study. The field studies were carried out in the summer and autumn of 2011 on harvesting sites managed by Metsähallitus and Metsäliitto in the Jyväskylä region. The study material comprises a total of 139 loads. There was a significant difference in raw density between the logging residues and stump pieces for the widening and compressing load space solutions. For this reason, it does not make sense to compare the two load space solutions to each other. The analyses were based on the reported load scale tonnes. Both load space alternatives increased the load size by 20-30 per cent depending on the assortment. For logging residues, the increase in efficient hour productivity for extraction was 13 per cent and for stump pieces it was 30 per cent. With the compressing load space, the efficient hour productivity for full trees increased by 17 per cent. For logging residues, the increase was 5 per cent and for stump pieces it was 12 per cent. Compression was not a successful method for stump pieces and even for logging residues the benefits were mainly based on the increased load space. Compressing the load is mainly beneficial when extracting full trees. The project was carried out together with Osuuskunta Metsäliitto (now Metsä Group), Metsä-Multia Oy and Ponsse Oyj. The modelling work was done by Metsäteho Oy. This study shows results of Metsähallitus project “Maastokuljetuksen kehittäminen”. The project is part of the EffFibre (Value through Intensive and Efficient Fibre Supply) research and development programme coordinated by Forestcluster Ltd.
  • Tolmatsova, Anastasia (Helsingfors universitet, 2012)
    The role of wood-based bioenergy has improved over the past few years after the European Union’s climate and energy directive came into effect. The main aim of the policy is to substitute fossil fuel with biofuels aim-ing to reduce greenhouse gas emissions, increase energy security and support the development of rural com-munities. To achieve this aim it is necessary to pursue more efficient energy use in living, construction and transport. Most of the EU countries have undertaken to participate in these actions by increasing the use of renewable energy such as wood-based bioenergy. Currently, wood-based bioenergy is highly supported with subsidies and other political decisions that act as the main market driver. Furthermore, the increasing prices of fossil fuels create favorable conditions for future bioenergy market developments. Nevertheless, the role of bioenergy is growing even though the market has its own challenges due to fluctuating forest industry cycles. To better understand the wood-based bioenergy market and its current situation, this Master’s thesis has ga-thered up-to-date information on three different market areas which will assist in finding potential delivery destinations within the Baltic Sea area for wood-based bioenergy produced in the Leningrad region. In addi-tion, this thesis introduces, on a broad scale, the central concepts of wood-based bioenergy and discusses the political drivers affecting bioenergy markets. The theoretical framework is mainly based on the Information Environment Model by Juslin and Hansen (2002), an instrument for investigating the bioenergy market from both macro and micro environment aspects, and on the Relationship Commitment and Trust theory by Morgan and Hunt (1994), which examines how relationships between buyers and sellers are established and discusses the role of two variables - trust and commitment. Both models were applied when collecting both the primary data from bioenergy customers through interviews and the secondary data from research articles, publications and Internet sources. The study also includes a discussion part as well as development proposals related to future customer relationship man-agement. Wood-based bioenergy is an important energy source fighting against climate change. However, to fulfill the targets set by the European Union and country-specific politics there is still a need for more opera-tors working in bioenergy field. Based on the results, it is necessary to support good communication, coopera-tion and trust between raw-material buyers and sellers in order to achieve functional raw-material exchange circumstances. The study is conducted as a qualitative research project.
  • Salonen, Hilma Annikki (2018)
    The Russian renewable energy industry has not yet succeeded in breaking through into the domestic market despite its potential, particularly in remote Arctic settlements. This article examines broad issues that influence national policy-makers and provides an analysis of the type of objectives that are emphasized in Russian energy policies. It can be assumed that the priorities behind these objectives have a more stable status than more concrete plans to boost the use of renewables, since they often fail to materialize. In order to discover these priorities, I analyze several relevant policy-making documents with the help of public justification analysis, a method developed to examine public claims made in favor of a certain cause, and the commonly known values that the claim-makers refer to in order to convince others. This paper reveals that Russian energy policy documents tend to emphasize concrete, technical tasks over more abstract, holistic goals. In addition, industrial needs dominate all policies, even those related to socio-economic or environmental issues. I conclude that the tendencies listed above may prevent fundamental structural change in the Russian energy industry, despite the potential of renewable energy, especially in the Arctic regions.
  • Kaarakka, Lilli Matilda; Vaittinen, Janne; Marjanen, Mikael; Hellsten, Sofie; Kukkola, Mikko; Saarsalmi, Anna; Palviainen, Marjo Maarit; Helmisaari, Heljä-Sisko Marketta (2018)
    Finland has a long tradition of utilizing forest-based biomass for energy and industry purposes and the use has steadily increased in the past decade due to changes in international and regional energy policies. Intensive harvesting practices, in which a larger proportion of the woody biomass is removed from the forest stand, are becoming more common. The objectives of this study were (i) to evaluate the spatial and temporal extent of soil surface disturbance caused by stump-root system harvesting and (ii) to quantify how much biomass and nitrogen is removed from the stand in stump and coarse root removal. The extent of surface disturbance was assessed in three clear-cut Norway spruce (Picea abies, (L.) Karst.) stands in southern and central Finland, differing in time since harvest. To determine the biomass distribution of the stump-root system, stumps and coarse roots were excavated at one of the experimental stands. Across all age classes (time since harvest) less soil surface had remained undisturbed at the stump harvesting sites (48%) than at the sites where only mechanical site preparation (72%) had been carried out. Thus, the findings of this study indicate that soil disturbance caused by stump harvesting can exist on forest soil surface for more than a decade following harvest. The total biomass of the stump-root system in the stand was estimated to 39.3 Mg ha-1 and 79% of this biomass was removed during stump harvesting and consequently, 8.3 Mg ha-1 of stump-root biomass remained in soil. The stump-root system accounted for 17% of the whole-tree biomass, and coarse roots and fine coarse roots represented a significant portion of it (73%). Thus, the stump-root system represents a large biomass component in boreal forest stands. However, forest management utilizing stumps may result in carbon losses from the stand.
  • Santangeli, Andrea; Di Minin, Enrico; Toivonen, Tuuli; Pogson, Mark; Hastings, Astley; Smith, Pete; Moilanen, Atte (2016)
    Increased deployment of renewable energy can contribute towards mitigating climate change and improving air quality, wealth and development. However, renewable energy technologies are not free of environmental impacts; thus, it is important to identify opportunities and potential threats from the expansion of renewable energy deployment. Currently, there is no cross-national comprehensive analysis linking renewable energy potential simultaneously to socio-economic and political factors and biodiversity priority locations. Here, we quantify the relationship between the fraction of land-based renewable energy (including solar photovoltaic, wind and bioenergy) potential available outside the top biodiversity areas (i.e. outside the highest ranked 30% priority areas for biodiversity conservation) within each country, with selected socio-economic and geopolitical factors as well as biodiversity assets. We do so for two scenarios that identify priority areas for biodiversity conservation alternatively in a globally coordinated manner vs. separately for individual countries. We show that very different opportunities and challenges emerge if the priority areas for biodiversity protection are identified globally or designated nationally. In the former scenario, potential for solar, wind and bioenergy outside the top biodiversity areas is highest in developing countries, in sparsely populated countries and in countries of low biodiversity potential but with high air pollution mortality. Conversely, when priority areas for biodiversity protection are designated nationally, renewable energy potential outside the top biodiversity areas is highest in countries with good governance but also in countries with high biodiversity potential and population density. Overall, these results identify both clear opportunities but also risks that should be considered carefully when making decisions about renewable energy policies.
  • Siintola, Asko (Helsingfors universitet, 2012)
    Climate change has been found to be one of the most serious challenges humankind has to face in the future. The link between climate change and forests is based on trees’ ability to use carbon dioxide as a raw material for growth. The growing stock sequesters carbon dioxide from the air to itself and ultimately as the forest is harvested the carbon stored is released and it moves from carbon pool of forests to another carbon pool. As the concept of emissions’ trading is applied to the investigation, a price for sequestered and released carbon can be determined. With the market price for carbon dioxide known, a net present value for the revenues and costs during the forest’s rotation period can be calculated. Using wood for different purposes, however, can result in various climatic benefits. These climatic benefits are described in this study by carbon displacement factors which can be used in determining how much the costs of releasing carbon from forests can be deducted. This study investigates the significance of forest management in a stand level from the climate change mitigation point of view in three Norway spruce (Picea abies, L.) and three Scots pine (Pinus Sylvestris, L.) stands as the previous carbon accounting aspects are taken into consideration. Stand Management Assistant (SMA) software is used in the optimization and simulation calculations. The SMA software is used for calculating the carbon accounting net present values and average carbon storages during the rotation periods of the stands included in the study with different intensities of bioenergy biomass harvesting. This way the level of biomass harvesting for bioenergy that returns with the highest net present value for carbon accounting and/or the highest average carbon storage can be calculated. The calculations are made with two interest rates, two carbon dioxide prices and with climatic benefits from bioenergy or with climatic benefits from bioenergy and forest products included. According to the results it can be stated that the intensification of forest biomass recovery for bioenergy production does not always result in the optimal climate change mitigation. The use of Norway spruce is considered of being the most potential forest-based bioenergy source in Finland. As the climatic benefits from bioenergy use were only taken into consideration, the intensification of recovery of Norway spruce biomass for bioenergy seemed to be most profitable. If, however, the climatic benefits from forest products are included in the investigation as well, the bioenergy use of Norway spruce is no longer optimal for the climate change mitigation. The climatic benefits from Norway spruce material use exceed the benefits from bioenergy use. This means that biomass recovery for bioenergy production does not necessarily result in optimal climate change mitigation.