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The bioeconomic potential of monopodial and sympodial bamboos is not well understood. Therefore, Net primary productivity (NPP), total biomass, carbon (C) stock, soil organic carbon (SOC), CO 2 sequestration, and bioenergy potential were studied in a sympodial Chimonocalamus griffithianus and a monopodial Phyllostachys mannii bamboo in Meghalaya, north-eastern India. P. mannii stand with mean culm density 16,877 ha−1, height 14.8 m and diameter 4.4 cm, accumulated 107.56 Mg ha−1 biomass with a total NPP of 18.83 t ha−1yr−1. It stored 50.67 Mg C ha−1 in biomass, 77.28 Mg C ha−1 in soil, and had sequestration potential of 469.58 t CO 2 ha−1. C. griffithianus stand with mean clump density 1065 ha−1, mean culm density 52,185 ha−1, height 7.19 m and diameter 3.04 cm, accumulated 67.08 Mg ha−1 biomass with a total NPP of 15.30 t ha−1 yr−1. It stored 31.30 Mg C ha−1 in biomass, 83.25 Mg C ha−1 in soil, and had sequestration potential of 420.40 t CO 2 ha−1. Matured culms (>2–3 years old) of P. manni and C. griffithianus produced 143.08–166.65 MW h and 87.13–101.48 MW h of energy per ha, respectively. Although landuse history and site characteristics of the two stands were not 100 % identical, significantly greater (p < 0.05) standing biomass, NPP, growth rate, carbon sequestration potential, and energy values of P. mannii than C. griffithianus makes the monopodial bamboo a better choice for energy plantation and climate change mitigation tool than the sympodial. • Monopodial bamboo, Phyllostachys mannii , surpasses sympodial Chimonocalamus griffithianus in bioeconomic potential. • P. mannii exhibits higher biomass, NPP, carbon sequestration, and energy values. • Comparative analysis reveals the superior suitability of monopodial bamboo for energy plantations. • Results provide valuable insights for sustainable development in India's biobased economy. • Study contributes to understanding the role of bamboos in mitigating climate change. [ABSTRACT FROM AUTHOR]

Rice, as a main crop, contributes to food security in Asia. However, its by-product, rice straw, poses challenges as it is often disposed of unsustainably. This research investigates the environmental performance of a 1000 m3 rice straw biogas pilot plant in Laguna, Philippines. A lifecycle assessment identified the climate change impact of the biogas system, straw burning and soil incorporation. In addition to GWP100, the global temperature potential's dynamic climate effects were assessed, including integrated radiative forcing and instantaneous temperature effects. The timeframe of the biogenic emission fluxes of rice production is particularly relevant as the sequestered CO 2 during plant growth is partly released as methane and CO 2 , depending on the straw management practices. Straw burning had the highest net emission impact. However, straw incorporation has the highest short-term radiative forcing and temperature increase. The biogas system provided significant short- and long-term GHG emission reduction of up to 68 % when biogas replaced burning or soil incorporation and the use of fossil fuels. Still, considerable uncertainties remain about fugitive methane emissions, handling and post-processing of the digestate. While single GHG emission figures on a GWP100 basis are useful for informing decision-making, this single-metric approach limits understanding of rice production's short- and long-term impacts. Additionally, our assessment emphasises the necessity for governance frameworks that promote sustainable practices in rice farming, as banning rice straw burning may result in less favourable outcomes from soil incorporation, whereas integrating biogas offers a solution benefiting rice-growing communities and global sustainability efforts. • Biogas from rice straw reduces emissions by up to 69 %. • Soil incorporation of straw has highest short-term (20 years) temperature increase. • Assessing more than one metric and timeframe supports more informed decision-making. • Governance frameworks enabling bioenergy integration support SDG 3, 7 and 13. [ABSTRACT FROM AUTHOR]

We examine the supply chains of post-fire salvage harvest to 28 mills or 10 communities in British Columbia, Canada, and assess the net change in GHG emissions for community bioenergy and biofuels, relative to a 'do-nothing' baseline with fossil fuel use. Lowest-cost supply chains for post-fire salvage had largest hauled biomass for mills in the southern interior of the province, with mills in close proximity to each other having small fibresheds and low haul costs. Supply chains were also quantified for salvage biomass hauled to communities by using a lowest GHG optimization routine that selected between liquid transportation fuels or community bioenergy (heat and/or electricity). For the first few decades, avoided GHG emissions were larger when biomass was used for bioenergy (heat and/or electricity), mainly in larger communities, to avoid fossil fuel burning. As energy systems decarbonized, biomass was used for biofuels, and production was more evenly distributed amongst the communities. Adding these results to an integrated framework with previously published ecosystem emissions and removals assessed the net change in GHG emissions for a post-fire rehabilitation and bioenergy scenario relative to a 'do-nothing' baseline with continued fossil fuel use. We found that there was an initial increase in net GHG emissions even though biogenic emissions from bioenergy were partially offset by avoided fossil fuel emissions. Over time, an enhanced sink from rehabilitation activities combined with avoided fossil fuel emissions resulted in a cumulative (2020–2070) GHG reduction at median levels of −6 TgCO 2 e with a range from reduced emissions of −39 TgCO 2 e to increased emissions 37 TgCO 2 e. Cumulative avoided fossil emissions were −62 TgCO 2 e with a range from −49 TgCO 2 e to −86 TgCO 2 e. • Supply chains of post-fire salvage harvest to communities and mills in British Columbia, Canada. • Integrated framework optimized net GHG emissions for bioenergy from forest rehabilitation. • Net cumulative GHG reduction was −6 TgCO 2 e (range −39 TgCO 2 e to 37 TgCO 2 e) over 50 years. [ABSTRACT FROM AUTHOR]

Abstract Forest-based bioenergy plays an important role in climate mitigation for limiting global mean temperature increase to below 2 °C. The greenhouse gas (GHG) impact of three forest-based bioenergy systems from the USA, Canada and Spain supplying wood pellets for electricity in the UK were evaluated by conducting lifecycle assessments and forest carbon modelling of the three forest systems. Cumulative emissions were analysed by calculating the forest carbon stock change and net GHG emissions balance of the forest-based bioenergy electricity. The analysis considered both the replacement of the existing electricity mix with bioenergy electricity and forest management with and without bioenergy use. The supply chain emissions and forest carbon balances indicated that GHG emission reductions are possible. However, the cumulative net GHG balance at forest landscape scale revealed that the reduction potential is limited, potentially with no GHG reductions in fast growing forests with shorter rotations, while slow growing forest systems with longer rotations result in greater GHG reductions. This means that the maximum climate benefit is delivered at a different point in time for different forest systems. To evaluate the climate change mitigation potential of forest-based bioenergy it is therefore necessary to consider the management, utilisation and relevant counterfactual of the whole forest and its products. In terms of climate change mitigation potential and minimising possible negative impacts that would require multi-level governance. Highlights • Net GHG balance shows GHG reduction potential of forest bioenergy is limited. • Results are dependent on methods, system boundaries and reference system. • Mitigation potential depends on forest management and whole forest product basket. • Multi-level governance framework require to track wider impacts of forest bioenergy. [ABSTRACT FROM AUTHOR]

Abstract The Paris Agreement brings countries together in a combined effort to combat climate change and its effects. A key target is the reduction of energy related greenhouse gas emissions. Providing biogas from biomass is one option to provide renewable and less carbon intensive fuels. When upgraded to biomethane it may be a substitute for natural gas and thus may have many application pathways. Recognising this potential many European countries installed governmental support programmes to stimulate market growth over the last decade. However, most of the installed schemes in Europe are time-limited. Besides being time-limited most of the schemes include a degression of compensation over time, resulting in many having limited success over longer time frames. This study questions the feasibility of near-term business cases for biomethane plants and analyses options for making them less dependent on governmental support programmes. Currently a market potential is seen in the utilization of process carbon dioxide in carbon capture and utilization or carbon capture and storage pathways, because it is a widely available side product from biogas upgrading. Therefore, we examined three business cases for its utilization in across sectors. To answer the research question we use a previously developed biomethane market simulation model and added an extension for new business cases. Results indicate that there are specific business options in the field of 2160 m³ h−1 to 20,840 m³ h−1 that are economical feasible under certain circumstances. Highlights • Use of CO2 in the chemical industry was not economically feasible even under optimistic conditions. • Utilization of carbon dioxide from biogas upgrading offers new business options. • Production of bio-LNG is a promising business option. [ABSTRACT FROM AUTHOR]

Cellulosic energy crops have been promoted in various jurisdictions for their potential to mitigate climate change and enhance energy security while avoiding some of the negative impacts associated with first-generation biofuel crops. However, the successful expansion of cellulosic energy cropping depends on its acceptance by local communities. The social licence to operate (SLO) concept has been applied in mining and other sectors since the late 1990s and offers a framework for analysing the relationships between energy cropping proponents and local communities. This review analyses recent cellulosic energy cropping studies to determine the extent to which they consider the key SLO variables of distributional fairness, procedural fairness, trust and adaptability. The results indicate that, of these four variables, trust has received the least coverage in previous studies focusing on the social dimensions of cellulosic energy cropping. This review also highlights a contrast between energy cropping studies that applied the SLO concept, all of which explicitly considered trust, and those studies that did not apply the SLO concept. This result highlights the potential role that the SLO concept could play in ensuring that the importance of trust is not overlooked by researchers, bioenergy proponents or policy-makers. [ABSTRACT FROM AUTHOR]

Rapid decarbonisation of the transport sector calls for increased use of biofuels. Part of the increase may be covered by fuels produced from logging residues, wood chips and round wood. This article addresses the economic potential and possible impacts of increased production of such wood based biofuels on the forest industries and production of wood based heat and power in the European Economic Area. A global model for the markets and trade of forest biomass and products, the EFI-GTM was applied for the analysis. The results indicate, firstly, that policy choices will have strong impacts on the allocation of biomass use between heat and power production and the production of liquid biofuels. Hence, the policy makers must have very clear goal setting for the preferred ways to solve the shift from the fossil fuel based energy system to a less carbon intensive one. Nevertheless, because large investments in biofuel production take time to plan and construct, and because the annual forest growth exceeds the harvests of wood in various parts of Europe, there is time to adjust the policies to control the market development. Secondly, even assuming the goal of limiting the global warming to 2 °C, the European forest industry production is projected to be rather little affected by the increased competition for biomass with the energy sector. This is because the rivalling regions are facing similar biomass demand challenges. Also, the relatively abundant wood biomass resources in Europe help the European forest industry to maintain its market shares. [ABSTRACT FROM AUTHOR]

Replacing fossil fuels by logging-residue-based bioenergy has been proposed as a way to mitigate climate change. If residues are combusted for energy, their carbon content is released immediately. Residues, that are not combusted, decompose and emit carbon gradually. The relative harmfulness of bioenergy emissions therefore depends on how strongly we prefer the slow release of carbon to an immediate one. Two factors affect this judgment: (1) our time preference and (2) our expectations regarding the relative harmfulness of future carbon emissions. Neither aspect is included in established biomass emission factors. The Effective Emission Factor (EEF), outlined in this study, includes both aspects in a transparent and tractable way. We demonstrate the concept by deriving the EEFs for the logging residues of three Nordic tree species: Norway spruce (Picea abies), Scots pine (Pinus sylvestris) and silver birch (Betula pendula). We also examine the sensitivity of the results to variation in time preference and damage expectations. The derived factors can be used to compare the harmfulness of carbon emissions from residue-based bioenergy and fossil fuel combustion and to organize bioenergy carbon taxation consistently with the taxation of fossil fuels. [ABSTRACT FROM AUTHOR]

The European Union relies largely on bioenergy to achieve its climate and energy targets for 2020 and beyond. We assess, using Attributional Life Cycle Assessment (A-LCA), the climate change mitigation potential of three bioenergy power plants fuelled by residual biomass compared to a fossil system based on the European power generation mix. We study forest residues, cereal straws and cattle slurry. Our A-LCA methodology includes: i) supply chains and biogenic-CO 2 flows; ii) explicit treatment of time of emissions; iii) instantaneous and time-integrated climate metrics. Power generation from cereal straws and cattle slurry can provide significant global warming mitigation by 2100 compared to current European electricity mix in all of the conditions considered. The mitigation potential of forest residues depends on the decay rate considered. Power generation from forest logging residues is an effective mitigation solution compared to the current EU mix only in conditions of decay rates above 5.2% a −1 . Even with faster-decomposing feedstocks, bioenergy temporarily causes a STR(i) and STR(c) higher than the fossil system. The mitigation potential of bioenergy technologies is overestimated when biogenic-CO 2 flows are excluded. Results based solely on supply-chain emissions can only be interpreted as an estimation of the long-term (>100 years) mitigation potential of bioenergy systems interrupted at the end of the lifetime of the plant and whose carbon stock is allowed to accumulate back. Strategies for bioenergy deployment should take into account possible increases in global warming rate and possible temporary increases in temperature anomaly as well as of cumulative radiative forcing. [ABSTRACT FROM AUTHOR]

This study aims to quantify the environmentally sustainable and economically feasible potentials of agricultural and agro-industrial residues to generate electricity via direct combustion in centralised power plants in Brazil. Further, the energy savings and greenhouse gas (GHG) reduction potential of replacing natural gas-based electricity by bioenergy have been assessed. To this end, a methodology has been developed based on an integrated evaluation, incorporating statistical and geographical information system (GIS)-based analysis, and a life-cycle-assessment approach. Results reveal that the environmentally sustainable generation potential is nearly 141 TWh/year, mainly concentrated in the South, Southeast, and Midwest regions of the country. Sugarcane, soybean and maize crop residues are the major feedstocks for available bioenergy. On the other hand, the economic potential is far lower, accounting to 39 TWh/year. The total GHG mitigation is nearly 18 million tonne CO 2 e and could reach 64 million tonne CO 2 e yearly, if the technical potential is considered. The gap between technical and economic potentials implies that constraints to bioenergy are not related to a lack of resources, but rather associated to economic, logistical, regulatory and political barriers. [ABSTRACT FROM AUTHOR]

Changes to energy systems are needed in order to reduce greenhouse gas emissions and mitigate climate change. This study assessed the climate change mitigation potential, in terms of temperature change over time, of a new combined heat and power (CHP) plant, including the dynamic effect on an existing fourth generation district heating system. The climate impact of combusting forest residues (tops and branches) was compared with combusting municipal solid waste (MSW), waste wood or hard coal. A scenario with wood chip combustion and carbon capture and storage (BECCS) was also assessed. The district heating system in Stockholm, Sweden, was used as a case study for the assessment. The results clearly show climate change mitigation potential of combusting wood chips, compared with hard coal and MSW, with this climate benefit increasing further with BECCS. The results also demonstrate the importance of time dynamic effects in the energy system and temperature response, highlighting the importance of not postponing implementation of climate change mitigation options if agreed climate targets are to be met on time. • This LCA integrated dynamic effects using the climate and energy system models. • BECCS further increases the climate change mitigation potential. • Implementation of climate change mitigation options should not be delayed. • There is value in taking an integrated dynamic perspective on energy systems. [ABSTRACT FROM AUTHOR]

Lignocellulosic bioenergy crops are a potential option for climate mitigation and for meeting the targets of the Paris Agreement in Europe. The PopFor process-based model has been developed based on the earlier MiscanFor model and parameterised for poplar using data from a literature review in combination with experimental data on high performing clones Max 1, 3, 4 for extensively and intensively managed sites in Germany. PopFor needs comparatively few input data to provide accurate estimates of biomass yield. The parameters found allowed a good match to measured values. The best fit for bud emergence is 81 °days (base 5), with leaf emergence at 463 °days (base 5) and the temperature at which photosynthesis slows is 28 °C. Maximum radiation use efficiency was set to 2.9 gMJ−1. The air temperature threshold that kills crop was set at −37 °C with the number of days below this threshold that kills the crop set at 90 days. 30 days below wiltpoint was set as a threshold that kills the crop from drought. It was found that plant available water was the key explanatory variable in predicting yield and access to groundwater explained 97% of the yield variation between the sites. The results show that the model estimates the yield of poplar after the establishment phase with a mean difference of 0.27 DM t ha−1 y−1 (r2 0.99, n29, F = 4.18, p < 0.05 with RMSE = 19.68%). PopFor was shown to be an effective model for predicting yields under different soil conditions. Image 1 • New poplar model for predicting yield estimates on a local or larger scale. • PopFor needs only soil and weather data, no diameter or stem measurements. • PopFor accurately modelled yield for 2nd rotation and intensively managed 1st rotation poplar coppice. • PopFor parameters are widely applicable. • PopFor is a suitable tool for defining the most suitable areas for poplar bioenergy. [ABSTRACT FROM AUTHOR]

Displacement of fossil fuels by forest bioenergy can contribute to climate change mitigation by reducing greenhouse gas (GHG) emissions. However, GHG savings are not realised until the avoided fossil emissions offset the loss of atmospheric carbon (C) that would have been sequestered if the biomass was not used for bioenergy (i.e. time to C sequestration parity). We estimated the potential for mitigating GHG emissions and the timing of these atmospheric benefits when substituting conventional natural gas (NG) with renewable natural gas (RNG) produced from different forestry feedstocks within three Canadian provinces, and assessed the uncertainty among these estimates. We calculated the GHG balance of RNG using the alternative fate of biomass and the use of NG as base-case scenarios. Immediate to long-term time to C sequestration parity was typically in the order of residues burned < mill residues < harvest residues decaying on site < salvaged trees. The potential GHG savings from using harvest and mill residues to produce RNG within the three provinces ranged from 52.4 to 77.8 Mt CO 2eq a−1. Sensitivity analyses suggest that time to C sequestration parity in the best-case scenarios relative to the baseline can be reduced up to 17 years by using harvest residues that decay rapidly (based on feedstock species, size and geographic region), and reduced up to 8 years by improving the efficiency of the thermochemical conversion process. These two considerations are key for ensuring significant GHG reductions from RNG use within a timescale that helps Canada meet its GHG mitigation targets. • Immediate GHG benefits for RNG produced with residues otherwise burned on site. • No short-term C sequestration parity time for RNG produced with forest residues. • C sequestration parity time >100 years for RNG produced with salvaged trees. • Potential net GHG savings of 52.4–77.8 Mt CO 2eq.year−1 for RNG use. [ABSTRACT FROM AUTHOR]