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Now showing 1 - 10 of 19
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    CUDe — Carbon utilization degree as an indicator for sustainable biomass use
    (Basel : MDPI, 2016) Anja Hansen, Anja Hansen; Budde, Jörn; Karatay, Yusuf Nadi; Prochnow, Annette
    Carbon (C) is a central element in organic compounds and is an indispensable resource for life. It is also an essential production factor in bio-based economies, where biomass serves many purposes, including energy generation and material production. Biomass conversion is a common case of transformation between different carbon-containing compounds. At each transformation step, C might be lost. To optimize the C use, the C flows from raw materials to end products must be understood. The estimation of how much of the initial C in the feedstock remains in consumable products and delivers services provides an indication of the C use efficiency. We define this concept as Carbon Utilization Degree (CUDe) and apply it to two biomass uses: biogas production and hemp insulation. CUDe increases when conversion processes are optimized, i.e., residues are harnessed and/or losses are minimized. We propose CUDe as a complementary approach for policy design to assess C as an asset for bio-based production. This may lead to a paradigm shift to see C as a resource that requires sustainable exploitation. It could complement the existing methods that focus solely on the climate impact of carbon.
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    The role of bioenergy in enhancing energy, food and ecosystem sustainability based on societal perceptions and preferences in Asia
    (Basel : MDPI, 2016) Acosta, Lilibeth A.; Magcale-Macandog, Damasa B.; Kavi Kumar, K.S.; Cui, Xuefeng; Eugenio, Elena A.; Macandog, Paula Beatrice M.; Salvacion, Arnold R.; Eugenio, Jemimah Mae A.
    This paper discussed the analysis of the survey on sustainability of bioenergy conducted in the Philippines, India and China. It acquired general perceptions of the people by asking them (a) specific questions about their level of familiarity with bioenergy; (b) relationship of their work to bioenergy; and (c) their opinion on contribution of various feedstock on the economy and impact of bioenergy production on food security. In addition to these questions, we estimated preference weights of various feedstock based on the conjoint choices on bioenergy’s contribution to social stability, social welfare and ecological balance. The estimates revealed significant trade-offs not only among these three dimensions of sustainability but also the relative importance of energy security, food security and ecosystem capacity to other economic, social and environmental objectives. The types of first generation feedstock that are currently used for biofuel production in the respective countries and those that offer alternative household use are perceived as important to the economy and preferred bioenergy feedstock. Based on the results of the study, the preferred role of bioenergy for sustainable development reflects the social and economic concerns in the respective Asian countries, e.g., energy security in China, food security in India, and ecosystem degradation in the Philippines.
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    The global technical potential of bio-energy in 2050 considering sustainability constraints
    (Amsterdam : Elsevier, 2010) Haberl, H.; Beringer, T.; Bhattacharya, S.C.; Erb, K.-H.; Hoogwijk, M.
    Bio-energy, that is, energy produced from organic non-fossil material of biological origin, is promoted as a substitute for non-renewable (e.g., fossil) energy to reduce greenhouse gas (GHG) emissions and dependency on energy imports. At present, global bio-energy use amounts to approximately 50 EJ/yr, about 10% of humanity's primary energy supply. We here review recent literature on the amount of bio-energy that could be supplied globally in 2050, given current expectations on technology, food demand and environmental targets ('technical potential'). Recent studies span a large range of global bio-energy potentials from ≈30 to over 1000 EJ/yr. In our opinion, the high end of the range is implausible because of (1) overestimation of the area available for bio-energy crops due to insufficient consideration of constraints (e.g., area for food, feed or nature conservation) and (2) too high yield expectations resulting from extrapolation of plot-based studies to large, less productive areas. According to this review, the global technical primary bio-energy potential in 2050 is in the range of 160-270 EJ/yr if sustainability criteria are considered. The potential of bio-energy crops is at the lower end of previously published ranges, while residues from food production and forestry could provide significant amounts of energy based on an integrated optimization ('cascade utilization') of biomass flows. © 2010 Elsevier B.V.
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    Uncertainty of biomass contributions from agriculture and forestry to renewable energy resources under climate change
    (Stuttgart : Gebrueder Borntraeger Verlagsbuchhandlung, 2015) Gutsch, M.; Lasch-Born, P.; Lüttger, A.B.; Suckow, F.; Murawski, A.; Pilz, T.
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    Simulating second-generation herbaceous bioenergy crop yield using the global hydrological model H08 (v.bio1)
    (Katlenburg-Lindau : Copernicus, 2020) Ai, Zhipin; Hanasaki, Naota; Heck, Vera; Hasegawa, Tomoko; Fujimori, Shinichiro
    Large-scale deployment of bioenergy plantations would have adverse effects on water resources. There is an increasing need to ensure the appropriate inclusion of the bioenergy crops in global hydrological models. Here, through parameter calibration and algorithm improvement, we enhanced the global hydrological model H08 to simulate the bioenergy yield from two dedicated herbaceous bioenergy crops: Miscanthus and switchgrass. Site-specific evaluations showed that the enhanced model had the ability to simulate yield for both Miscanthus and switchgrass, with the calibrated yields being well within the ranges of the observed yield. Independent country-specific evaluations further confirmed the performance of the H08 (v.bio1). Using this improved model, we found that unconstrained irrigation more than doubled the yield under rainfed condition, but reduced the water use efficiency (WUE) by 32 % globally. With irrigation, the yield in dry climate zones can exceed the rainfed yields in tropical climate zones. Nevertheless, due to the low water consumption in tropical areas, the highest WUE was found in tropical climate zones, regardless of whether the crop was irrigated. Our enhanced model provides a new tool for the future assessment of bioenergy–water tradeoffs.
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    Spatially explicit analysis identifies significant potential for bioenergy with carbon capture and storage in China
    ([London] : Nature Publishing Group UK, 2021) Xing, Xiaofan; Wang, Rong; Bauer, Nico; Ciais, Philippe; Cao, Junji; Chen, Jianmin; Tang, Xu; Wang, Lin; Yang, Xin; Boucher, Olivier; Goll, Daniel; Peñuelas, Josep; Janssens, Ivan A.; Balkanski, Yves; Clark, James; Ma, Jianmin; Pan, Bo; Zhang, Shicheng; Ye, Xingnan; Wang, Yutao; Li, Qing; Luo, Gang; Shen, Guofeng; Li, Wei; Yang, Yechen; Xu, Siqing
    As China ramped-up coal power capacities rapidly while CO2 emissions need to decline, these capacities would turn into stranded assets. To deal with this risk, a promising option is to retrofit these capacities to co-fire with biomass and eventually upgrade to CCS operation (BECCS), but the feasibility is debated with respect to negative impacts on broader sustainability issues. Here we present a data-rich spatially explicit approach to estimate the marginal cost curve for decarbonizing the power sector in China with BECCS. We identify a potential of 222 GW of power capacities in 2836 counties generated by co-firing 0.9 Gt of biomass from the same county, with half being agricultural residues. Our spatially explicit method helps to reduce uncertainty in the economic costs and emissions of BECCS, identify the best opportunities for bioenergy and show the limitations by logistical challenges to achieve carbon neutrality in the power sector with large-scale BECCS in China.
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    Environmental co-benefits and adverse side-effects of alternative power sector decarbonization strategies
    ([London] : Nature Publishing Group UK, 2019) Luderer, Gunnar; Pehl, Michaja; Arvesen, Anders; Gibon, Thomas; Bodirsky, Benjamin L.; de Boer, Harmen Sytze; Fricko, Oliver; Hejazi, Mohamad; Humpenöder, Florian; Iyer, Gokul; Mima, Silvana; Mouratiadou, Ioanna; Pietzcker, Robert C.; Popp, Alexander; van den Berg, Maarten; van Vuuren, Detlef; Hertwich, Edgar G.
    A rapid and deep decarbonization of power supply worldwide is required to limit global warming to well below 2 °C. Beyond greenhouse gas emissions, the power sector is also responsible for numerous other environmental impacts. Here we combine scenarios from integrated assessment models with a forward-looking life-cycle assessment to explore how alternative technology choices in power sector decarbonization pathways compare in terms of non-climate environmental impacts at the system level. While all decarbonization pathways yield major environmental co-benefits, we find that the scale of co-benefits as well as profiles of adverse side-effects depend strongly on technology choice. Mitigation scenarios focusing on wind and solar power are more effective in reducing human health impacts compared to those with low renewable energy, while inducing a more pronounced shift away from fossil and toward mineral resource depletion. Conversely, non-climate ecosystem damages are highly uncertain but tend to increase, chiefly due to land requirements for bioenergy.
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    Europe’s renewable energy directive poised to harm global forests
    ([London] : Nature Publishing Group UK, 2018) Searchinger, Timothy D.; Beringer, Tim; Holtsmark, Bjart; Kammen, Daniel M.; Lambin, Eric F.; Lucht, Wolfgang; Raven, Peter; van Ypersele, Jean-Pascal
    This comment raises concerns regarding the way in which a new European directive, aimed at reaching higher renewable energy targets, treats wood harvested directly for bioenergy use as a carbon-free fuel. The result could consume quantities of wood equal to all Europe’s wood harvests, greatly increase carbon in the air for decades, and set a dangerous global example.
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    Correcting a fundamental error in greenhouse gas accounting related to bioenergy
    (Amsterdam [u.a.] : Elsevier, 2012) Haberl, H.; Sprinz, D.; Bonazountas, M.; Cocco, P.; Desaubies, Y.; Henze, M.; Hertel, O.; Johnson, R.K.; Kastrup, U.; Laconte, P.; Lange, E.; Novak, P.; Paavola, J.; Reenberg, A.; van den Hove, S.; Vermeire, T.; Wadhams, P.; Searchinger, T.
    Many international policies encourage a switch from fossil fuels to bioenergy based on the premise that its use would not result in carbon accumulation in the atmosphere. Frequently cited bioenergy goals would at least double the present global human use of plant material, the production of which already requires the dedication of roughly 75% of vegetated lands and more than 70% of water withdrawals. However, burning biomass for energy provision increases the amount of carbon in the air just like burning coal, oil or gas if harvesting the biomass decreases the amount of carbon stored in plants and soils, or reduces carbon sequestration. Neglecting this fact results in an accounting error that could be corrected by considering that only the use of 'additional biomass' - biomass from additional plant growth or biomass that would decompose rapidly if not used for bioenergy - can reduce carbon emissions. Failure to correct this accounting flaw will likely have substantial adverse consequences. The article presents recommendations for correcting greenhouse gas accounts related to bioenergy.
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    A Review of Biomass Briquette Binders and Quality Parameters
    (Basel : MDPI, 2022) Obi, Okey Francis; Pecenka, Ralf; Clifford, Michael J.
    The adverse effect of the use of fossil fuels on the environment and public health has given rise to a sustained renewable energy research and development. An important component of global renewable energy mix is the use of loose biomass, including agricultural and forestry residues, to produce solid fuels in the form of briquettes. Briquettes play a significant role in bioenergy mix in developing and developed countries. The production of biomass briquettes often entails the collection, transportation, storage, processing, and compaction of loose biomass that meet specific quality parameters. The densification process often involves the addition of binders to improve the cohesive strength of the briquette material. This paper surveys recent literature from 2012 to 2021 to establish the current state of research on the use of binders in briquette production; and reviews current parameters used in assessing the quality of biomass briquettes with focus on mechanical and handling properties. While a number of quality parameters were identified, their assessment methodologies varied widely in the literature, thus necessitating standardization for comparability purposes. The review also includes factors affecting the wide production and adoption of biomass briquettes in most developing economies and proposes ways of overcoming the bottlenecks.