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The timber industry in Ireland is an important producer of wood products for export and indigenous use, and supplies significant volumes of sawmill co-products as biomass for energy generation. This research expands existing knowledge on the environmental impacts of wood supply chains in Ireland by widening the analysis to incorporate the wood processing stage. The study determines and analyses energy and material inputs in the production of several timber products; sawnwood, wood chip, wood-based panel (WBP) boards and wood pellets, with an analysis of the resulting greenhouse gas emissions. Forestry operations and transportation make an important contribution to overall emissions. Electricity usage is responsible for the majority of emissions in sawmilling. Integration of combined heat and power (CHP) systems with sawmilling and pellet manufacture reduces greenhouse gas (GHG) emissions. The penetration of renewables in the Irish national grid mix is forecast to increase by 2020 in line with EU renewable energy targets. Analysis shows that the forecast fall in the carbon intensity of the grid will have a positive effect on the reduction of GHG emissions from the wood processing supply chains. Wood energy products compare favourably with other sources of biomass energy and with fossil fuels. [ABSTRACT FROM AUTHOR]

Abstract: The biofuels penetration rate target in Ireland for 2013 is 6% by volume. In 2012 the fuel blend reached 3%, with approximately 70 million litres of biodiesel and 56 million litres of ethanol blended with diesel and gasoline respectively. For January and February 2013, the blend rate had only reached 2.7%. The target of 10% by 2020 remains which equates to approximately 420 million litres. Achieving the biofuels target would require 345ktoe by 2020 (14,400TJ). Utilising the indigenous biofuels outlined in this paper leaves a shortfall of approximately 12,000TJ or 350 million litres (achieving 17% of the 10% target) that must be either be imported or met by other renewables. 70% of indigenous production from one biodiesel plant is currently from TME and UCOME. If this remains for 2020 then only 30% remains equating to approximately 10 million litres indigenous production for a second biodiesel plant (30% of 21+13 million litres) which has planned capacity of 40 million litres (36,000t). In terms of the EU biofuels sustainability criteria, up to 2017, a 35% GHG emissions reduction is required compared to fossil fuels. From 2017 onwards, a 50% GHG reduction is required for existing installations and a 60% reduction for new installations. [Copyright &y& Elsevier]

Highlights: [•] Wood energy supply chains are analysed for energy requirements and GHG emissions. [•] Use of residues and stumps for energy is evaluated for Irish conditions. [•] Results highlight transportation as the most energy and GHG emission intensive step. [•] Wood energy compares favourably with other biomass sources and fossil fuels. [ABSTRACT FROM AUTHOR]

Highlights: [•] 18 Sawmills, 3 board plants and the 3 peat fired power stations were included. [•] Cost of transport to Energy sector ranged from €306043 to €996842 in Scenario 2015. [•] The increased demand in 2030 led to a range of between €1,132,831 and €4,926,040. [•] A subsidy of between 140 and 170€TJ−1 is needed for Scenario 2015. [•] The subsidy decreases to 30 and 70€TJ−1 for Scenario 2030. [ABSTRACT FROM AUTHOR]

Abstract: The environmental impact of bioenergy supply systems can be determined using life cycle assessment methodologies. This study focuses on the impact of production of Miscanthus pellets and briquettes, potentially used to satisfy renewable energy requirements in Ireland. The impact categories considered are particularly important when assessing bioenergy systems; global warming potential, acidification potential, eutrophication potential, and energy demand. The scope of the study incorporates Miscanthus cultivation, harvest, processing and transport to a biomass distributor. The aim of the research is to evaluate the effects of changes in keys variables on the overall environmental impacts of the system. The scenarios examined include replacement of synthetic fertilisers with biosolids, Miscanthus processing by pelleting and briquetting, and transport distances of 50 and 100km. Results indicate that maintenance and processing of the Miscanthus crop have the most environmental impacts with transport having less of an effect. Replacing synthetic fertiliser with biosolids results in a reduction in global warming potential of 23–33% and energy demand of 12–18%, but raises both acidification and eutrophication potential by 290–400% and 258–300%, respectively. Pelleting of Miscanthus requires more energy than briquetting, hence has higher impacts in each category assessed. Increasing the transport distance from 50 to 100km, results in a small increase in each impact category. Miscanthus briquette production compares favourably with wood pellet, kerosene, and coal production, with Miscanthus pelleting proving more environmentally damaging. [Copyright &y& Elsevier]

Abstract: The purpose of this study was to analyse how biomass based haulage in Ireland performed as a measure of efficiency under 4 main criteria; distance travelled, fuel consumption, fuel consumption per unit of biomass hauled and diesel CO2 emissions. The applicability of truck engine diagnostic equipment was tested to analyse the schedule of engine data that could be recorded in real-time from a 5 axle articulated biomass truck. This identified how new on board truck technology in Ireland could be used to monitor data in real-time, specifically fuel consumption, litre/km, litre/ton and distance to allow for informed analysis of how efficient new biomass trucking operations currently are in Ireland. Fleet Management System (FMS) monitoring systems are a relatively new technology in biomass and log transport in Ireland. They are more common place in the food supply chain with refrigerated units travelling across continental Europe where food temperature and truck movements are controlled data from a central dispatch. A GPS asset tracking monitoring system was also installed on the truck over the test period to record trip log data. The BT (biomass truck) was a 5 axle, 2004 DAF XF Euro III 430hp 4*2. Initial results showed that for the BT, the average daily fuel consumption varied from 0.23 L/km to 0.47 L/km. The thresholds of travelled distance were between 20.92 km and 434.91 km respectively with average fuel consumption per tonnage of woodchips of 0.16 L/ton and 5.68 L/ton. When the total daily distance is limited to 1 load within 200 km roundtrip versus 1 load at approximately 400 km trip, the % difference in logistic cost (€/T) is 56%. Delivering 2 loads per 400 km trip shows a 5.4% decrease in logistic costs versus the Trip 1 scenario confirming the increased efficiency of a more localised transport approach. A maximum percentage difference in costs of 45% that exists between a 2 load and 1 load trip occurs for Trip 22 and Trip 5 but this increases to 72% when analysing for 2 load versus 1 load for distances over 400 km. Trip 7 and 12 are both below 50 km and seem to be the exception and to compare could possibly show an element of distortion. The closest logistic cost to Trip 12 is Trip 5 with 113% higher costs confirming how a 50 km roundtrip can impact significantly on lowering biomass transport costs. [Copyright &y& Elsevier]

Abstract: This research details the characterisation of four Irish-grown lignocellulosic biomasses for pyrolysis by biomass composition analysis, TGA, and Py-GC/MS-FID. Ash content (mf) increased in the order spruce (0.26wt.%)

Abstract: Robust alternative technology choices are required in the paradigm shift from the current crude oil-reliant transport fuel platform to a sustainable, more flexible transport infrastructure. In this vein, fast pyrolysis of biomass and upgrading of the product is deemed to have potential as a technology solution. The objective of this review is to provide an update on recent laboratory research and commercial developments in fast pyrolysis and upgrading techniques. Fast pyrolysis is a relatively mature technology and is on the verge of commercialisation. While upgrading of bio-oils is currently confined to laboratory and pilot scale, an increased understanding of upgrading processes has been achieved in recent times. [Copyright &y& Elsevier]

Abstract: Since the late 1980s, GIS (geographical information systems) have evolved to fully enable the range of capabilities needed in transportation routing, research and management. The objective of this paper was to analyse the designation of articulated haulage routes from one central depot to various destinations around the country of Ireland in terms of road class, distance, speed and travel time and compare the results with simulated routes generated within the GIS. The analysis incorporated a digitised road map of Ireland, where the GPS routes could be overlayed, together with ESRI’s (Environmental Systems Research Institute Inc., CA) ArcGIS software. The ArcInfo Network Analyst Tool (NAT) was used to compare routes generated by Dijkstra’s routing algorithm with the actual GPS routes in terms of road classifications, distance, speed and journey time of the route selected i.e. ‘destination planning’, a term used here to describe the shortest optimum route based on road class, road length, road speed and route journey time. Results showed that the shortest path (in terms of distance) determined by the NAT did not replicate the actual GPS routes. However, when the NAT was manipulated and used to determine the routes based on road classes i.e. routing to higher classes of roads and not distance (by applying a cost weighting within the geometric network), then the GPS routes were over 90% similar with what was modelled within the GIS. This may allow the GIS alone to be used in the network analysis of truck routing and in particular, timber truck routing from forest harvesting site to destination timber mill in Ireland and incorporate the use of GPS for other advantages such as real-time tracking and monitoring of timber movement. [Copyright &y& Elsevier]

This study provides a state-of-the art overview of forest biomass harvesting technologies and supply chains used in North America, Europe and the Southern Hemisphere. The productivity and cost of selected efficient technologies is presented for each country with a brief description about the source of the biomass and harvesting method. Expert opinions on the most successful biomass operations have been presented briefly for each country. The main conclusions from various intentional studies are provided in addition to future requirements for research and development. This report can be a useful high level guide of technology and supply chain selection for industry and academics. [ABSTRACT FROM AUTHOR]

The energy sector is the major contributor to GHG (greenhouse gas emissions) in Ireland. Under EU Renewable energy targets, Ireland must achieve contributions of 40%, 12% and 10% from renewables to electricity, heat and transport respectively by 2020, in addition to a 20% reduction in GHG emissions. Life cycle assessment methodology was used to carry out a comprehensive, holistic evaluation of biomass-to-energy systems in 2020 based on indigenous biomass supply chains optimised to reduce production and transportation GHG emissions. Impact categories assessed include; global warming, acidification, eutrophication potentials, and energy demand. Two biomass energy conversion technologies are considered; co-firing with peat, and biomass CHP (combined heat and power) systems. Biomass is allocated to each plant according to a supply optimisation model which ensures minimal GHG emissions. The study shows that while CHP systems produce lower environmental impacts than co-firing systems in isolation, determining overall environmental impacts requires analysis of the reference energy systems which are displaced. In addition, if the aims of these systems are to increase renewable energy penetration in line with the renewable electricity and renewable heat targets, the optimal scenario may not be the one which achieves the greatest environmental impact reductions. [ABSTRACT FROM AUTHOR]

The ever increasing energy demand along with fast depleting non-renewable fossil fuels and global climate change has led to a search for alternative energy resources. Waste plastic fuels have gained significant interest since they not only solve disposal problems but also provide an alternative energy resource. Combustion analysis of waste plastic derived fuels has shown conflicting findings with respect to fuel consumption and hazardous emissions. This is due to the conversion process employed (e.g., thermal vs. catalytic pyrolysis) and plastic type utilized resulting in a diverse range of fuel properties (i.e., viscosity and cetane Number). In this effort, a commercially-derived fuel (CynDiesel™) made from a blend of waste plastics through catalytic pyrolysis was tested as a blend with Ultra Low Sulfur Diesel (5%, 10%, 20%, and 100% by volume) to better understand the changes to pre-mixed and diffusion burn phases as a function of fuel properties. The significantly large cetane Number of this fuel combined with its relatively higher viscosity dramatically reduced the more efficient pre-mixed combustion phase; however, fuel consumption remained constant because of its greater energy content by mass. As a result, in-cylinder temperatures were found to be higher at high loads, but nitrogen oxide (NO x ) emissions went down with CynDiesel™ content. Furthermore, a theorized reduction in aromatic content and shift to saturated bonds with blend percentage resulted in lower hydrocarbon (HC) and carbon monoxide (CO) emissions even though particulate matter (PM) emissions increased because of the growth of the diffusion burn phase. At low blend contents, the waste plastic derived fuel did not adversely influence engine performance; however, there were apparent differences in the emissions profile. [ABSTRACT FROM AUTHOR]

The aim of this study was to analyse the supply of wood biomass (short wood) to the three peat power plants in Ireland and the impacts on the competing wood-based panel industries. The methodology includes the development of a spatial decision support tool based on LP (Linear Programming). It uses drying curves to assess the moisture content, weight and energy content of biomass during a two year period planning. Harvesting, chipping, storage and transportation costs are calculated based on the biomass moisture content. The model optimally allocates woodchips and logs from thinnings and clearfells. Results show that the planned maximum 30% co-firing rate at the three peat power station could be met with the forecasted short wood availability from both the private and public sector. The costs of supply increased not only with higher demands, but also with tighter constraints on the MC demanded by power plants. Spatial distribution and operational factors such as efficiency in transportation and truck loading showed to be sensitive to changes in MC. The analysis shows the benefits of managing the MC when optimising supply chains in order to deliver biomass to energy plants in a cost-effective manner. [ABSTRACT FROM AUTHOR]

In the coming years, Ireland will continue to face an increasing demand for wood biomass as a renewable source of energy. This will result in strained supply/demand scenarios, which will call for new planning and logistics systems capable of optimizing the efficient use of the biomass resources. In this study, a linear programming tool was developed which includes moisture content (MC) as a driving factor for the cost optimisation of two supply chains that use short wood and whole trees from thinnings as material feedstock. The tool was designed and implemented to analyse the impact of moisture content and truck configurations (5-axle and 6-axle trucks) on supply chain costs and spatial distribution of the supply materials. The results indicate that the inclusion of wood chips from whole trees reduces the costs of wood energy supply in comparison with only producing wood chips from short wood to satisfy the demand, with 9.8% and 10.2% cost reduction when transported with 5-axle and 6-axle trucks respectively. Constraining the MC of the wood chips delivered to the power plant increases both transport and overall supply chain costs, due, firstly to an increase in the haulage distance and secondly, to the number of counties providing the biomass material. In terms of truck configuration, the use of 6-axle trucks resulted in a 14.8% reduction in the number of truckloads and a 12.3% reduction in haulage costs in comparison to the use of 5-axle trucks across the MC scenarios analysed. [ABSTRACT FROM AUTHOR]