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Torrefaction is a thermal pre-treatment process for upgrading raw biomass into a more energy dense fuel. Torrefied biomass is combined with a densification process to increase its bulk density similar to conventional wood-pelleting production. This paper identifies the significant environmental impacts associated with production and delivery of these two fuels, using cradle-togate life cycle assessment. A feedstock of Scots Pine is modelled for a localised torrefaction/wood pellet plant located in Norway, with the products from each facility delivered to a power station in the UK. Results show that the relative benefits of torrefaction over wood-pellets are higher on per MJ delivered basis due to the higher calorific value of the fuel. The climate change and fossil depletion impacts for torrefied pellets modelled were lower than wood pellets, using an assumption that the drying requirement of the reactor was 3.0MJ/kg water removed for both cases. Sensitivity analysis of the model indicated that the relative impact improvement of the torrefied pellet case compared to wood pellets is strongly dependent on the biomass drying requirement and the proportion of total process heat supplied by the re-circulated torrefaction gas. Land requirements for torrefied pellets are higher due to the mass losses in production. Highlights • Life Cycle Assessment performed to assess torrefaction in wood pellet production • Comparative LCA of wood pellet production with and without torrefaction stage • Torgas recirculation allows for reduced demand for external utility fuel supply • Torrefied pellets offer energy and greenhouse gas savings but increase land use • Results are sensitive to assumptions on energy required for drying and torgas use

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Short rotation plantations (SRPs) are fast‐growing trees (such as willow (Salix spp.), poplar (Populus spp.) and Eucalyptus) grown closely together and harvested in periods of 2–20 years. There are around 50,000 hectares of SRPs in Europe, a relatively small area considering that there have been supportive policy measures in many countries for 30 years. This paper looks at the effect that the policy measures used in different EU countries have had, and how other external factors have impacted on the development of the industry. Rokwood was a 3‐year European funded project which attempted to understand the obstacles and barriers facing the woody energy crops sector using well established methods of SWOT and PESTLE analysis. Stakeholder groups were formed in six different European regions to analyze the market drivers and barriers for SRP and propose ways that the industry could make progress through targeted research and development and an improved policy framework. Based upon the outcomes of the SWOT and PESTLE analysis, each region produced a series of recommendations for policymakers, public authorities, and government agencies to support the development, production, and use of SRP‐derived wood fuel in each of the partner countries. This study provides details of the SRP policy analysis and reveals that each region shared a number of similarities with broad themes emerging. There is a need to educate farmers and policymakers about the multifunctional benefits of SRPs. Greater financial support from regional and/or national government is required in order to grow the SRP market. Introducing targeted subsidies as an incentive for growers could address lack of local supply chains. Long‐term policy initiatives should be developed while increasing clarity within Government departments. Research funding should enable closer working between universities and industry with positive research findings developed into supportive policy measures.

Background: Prior research in 2005 and 2008 estimated planted forest investment returns for a set of countries and included some natural forest species in a few countries. This research has extended those analyses to a larger set of countries and focused on plantation species, for seven years. This research serves as a "benchmarking" exercise that helps identify comparative advantages among countries for timber investment returns, as well as other institutional, forestry, and policy factors that affect investments. Furthermore, it extends the analyses to examine the effects of land prices, environmental regulations, and increased productivity on timber investment returns, as well as comparing timber returns with traditional stock market returns.

Whilst life cycle assessment (LCA) boundaries are expanded to account for negative indirect consequences of bioenergy such as indirect land use change (ILUC), ecosystem services such as water purification sometimes delivered by perennial bioenergy crops are typically neglected in LCA studies. Consequential LCA was applied to evaluate the significance of nutrient interception and retention on the environmental balance of unfertilised energy willow planted on 50-m riparian buffer strips and drainage filtration zones in the Skåne region of Sweden. Excluding possible ILUC effects and considering oil heat substitution, strategically planted filter willow can achieve net global warming potential (GWP) and eutrophication potential (EP) savings of up to 11.9 Mg CO 2 e and 47 kg PO 4 e ha -1 year -1 , respectively, compared with a GWP saving of 14.8 Mg CO 2 e ha -1 year -1 and an EP increase of 7 kg PO 4 e ha -1 year -1 for fertilised willow. Planting willow on appropriate buffer and filter zones throughout Skåne could avoid 626 Mg year -1 PO 4 e nutrient loading to waters.

Biomass gasification is regarded as a sustainable energy technology used for waste management and producing renewable fuel. Using the techniques of life cycle assessment (LCA) and net energy analysis this study quantifies the energy, resource, and emission flows. The purpose of the research is to assess the net energy produced and potential environmental effects of biomass gasification using wood waste. This paper outlines a case study that uses waste wood from a factory for use in an entrained flow gasification CHP plant. Results show that environmental impacts may arise from toxicity, particulates, and resource depletion. Toxicity is a potential issue through the disposal of ash. Particulate matter arises from the combustion of syngas therefore effective gas cleaning and emission control is required. Assessment of resource depletion shows natural gas, electricity, fossil fuels, metals, and water are all crucial components of the system. The energy gain ratio is 4.71MJdelivered/MJprimary when only electricity is considered, this increases to 13.94MJdelivered/MJprimary when 100% of the available heat is utilised. Greenhouse gas emissions are very low (7-15gCO2e/kWhe) although this would increase if the biomass feedstock was not a waste and needed to be cultivated and transported. Overall small-scale biomass gasification is an attractive technology if the high capital costs and operational difficulties can be overcome, and a consistent feedstock source is available. Highlights• Life Cycle Assessment performed to assess environmental effects of biomass gasification • Environmental impacts can include toxicity, particulates, and resource depletion • Net energy analysis shows very positive energy gains and short energy payback period • Low greenhouse gas emissions compared to fossil fuels and other bioenergy systems • Efficient waste management technology producing renewable heat and electricity