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The growing economic importance of the biomass-for-bioenergy in Europe motivates research on biomass supply chain design and planning. The temporally and geographically fragmented availability of woody biomass makes it particularly relevant to find cost-effective solutions for biomass production, storage and transportation up to the consumption facility. This paper addresses tactical decisions related with optimal allocation of wood chips from forest residues at forest sites to terminals and power plants. The emphasis is on a “hot-system” with synchronized chipping and chips transportation at the roadside. Thus, decisions related with the assignment of chippers to forest sites are also considered. We extend existing studies by considering the impact of the wood chips energy content variation in the logistics planning. This is a key issue in biomass-for-bioenergy supply chains. The higher the moisture content of wood chips, the lower its net caloric value and therefore, a larger amount of chips is needed to meet the contracted demand. We propose a Mixed Integer Programming (MIP) model to solve this problem to optimality. Results of applying the model in a biomass supply chain case in Finland are presented. Results suggest that a 20% improvement in the supplier profit can be obtained with the proposed approach when compared with a baseline situation that relies on empirical estimates for a fixed and known moisture content in the end of an obliged storage age. [ABSTRACT FROM AUTHOR]

This paper makes projections of the theoretical and technical potentials of bioenergy supply for 2050. The projections consider changes in available land for bioenergy and food for the global demand and advancements in yield, productivity, expansion of bio-waste recovery, and energy conversion. We present a literature review on projections. We introduced a novel logical and transparent forecasting model. Three future scenarios were established: business as usual (BUS), optimistic trends (OPT), and full adaptation response (FAR). The projection is carried out based on four adjusting factors. An uncertainty analysis was carry-out based on a Monte-Carlo method. Projections of bioenergy production in 2050 were compared with other projections in the literature. The FAR scenario showed that it would be possible to produce twenty-one times the current primary bioenergy supply and to even supply all global primary energy demand in 2050, mostly by energy crops. The assumptions adopted for the BUS and OPT scenarios make their projections more likely. Therefore, the contribution of bioenergy in the global energy matrix is expected to be between 64 and 313 EJ (7.5%–37%) in 2050. There would be a significant change in the composition of the bioenergy supply from today's mostly firewood to energy crops and biowastes. The technical potential for fuel and electric power mostly follow the supply trends for primary bioenergy (theoretical). The potential avoided greenhouse emissions are estimated. The heuristics and the level of transparency of the novel model will allow adjustments and exploration of other scenarios as time passes. • Novel model for projections of the potential of global primary bioenergy supply. • Bioenergy supply potential is shown for 11 different groups of biomass. • Global primary bioenergy supply could increase up to 6 times by 2050 (37% of demand). • Full adaptation response scenario could meet 100% of the global energy demand. • Bioenergy can play a major role in the global energy supply. [Display omitted] [ABSTRACT FROM AUTHOR]

The population of Mozambique''s capital Maputo relies to a large extent on wood fuel to meet its energy needs. The paper, based on a sample of 168 non-domestic and 240 domestic consumers, shows that domestic households constitute the most important wood fuel users in the city. Domestic consumption is now between 0.9 and 1.0 m3 of woody biomass per capita, an increase of more than 10% compared to data from the 1980s. This increase occurs despite a growing importance of alternatives such as paraffin, gas and electricity, and can be explained by the substitution of firewood by charcoal. The paper also shows a strong correlation between fuel consumption and socio-economic factors such as household size, area of residence and income. A striking feature is that similar to poorer families higher income households tend to use charcoal in combination with non-woody fuels, contradicting FAO''s (1993) “fuel ladder”. The paper argues finally that the importance of social economic factors inflicts a dynamism on fuel consumption patterns, which makes it necessary to monitor them on a regular instead of an ad hoc basis, as is the case now. [Copyright &y& Elsevier]

The paper discusses alternatives for biofuel-based district heating using simulation analysis in a real-life case example. First, the paper illustrates the current supply chain structure of forest chips from harvest to the heat energy plant. Usually the chips are naturally dried, chipped on the roadside and transported to the heating plant based on the orders. Second, the study demonstrates how a regional bioenergy system could be developed with the help of a simulation model for evaluating the feasibility of different wood fuel supply chain options. The model mimics a real-life example of an industrial area in a small Finnish municipality planning to invest in a CHP plant. The results show that the investment in a CHP plant and use of artificially dried wood fuel can be profitable in the circumstances where local demand exists for heat energy. The simulation-based vision can be compared with the presently dominant concept of highly decentralized supply chains for wood chips that is widely used among energy suppliers. However, to optimize the transportation costs and the moisture content of the chips changes are needed in the supply chain processes and structure. The results of this study are useable for practical decision-making and offer useful ideas for continuing research on alternative ways to produce energy wood biomass in the future. • Supply chain of forest chips in Finland is presented. • A real-life case of an industrial area demostrating how a regional bioenergy system could be developed is presenting. • The simulation model created minics the real-life case. • Feasibility of different wood fuel supplu chain options are discussed. [ABSTRACT FROM AUTHOR]

Abstract: In this paper, we analyze the determinants of the demand for firewood by Norwegian households, focusing on intrinsic factors such as lifestyle and environmental attitudes, along with household socioeconomic characteristics. The data are from the Norwegian Consumer Expenditure Survey and a supplementary questionnaire on energy consumption and lifestyle. We apply a zero-inflated negative binomial model to correct for overdispersion and the excessive number of zeros in the data. The results indicate that an urban lifestyle and concerns for comfort are negatively associated with firewood demand. In addition, price has a strong negative effect on demand. However, the most important determinants of household firewood demand are the characteristics of the household residence, including location, and household characteristics such as age and income. [Copyright &y& Elsevier]

Abstract Chipping weighs heavily on the total delivered cost of wood fuel, which calls for accurate chipping cost estimates. Chipper repair and maintenance cost is perhaps the most obscure among the figures required for a reliable estimate of chipping cost. To clarify this issue, the authors examined the long-term repair and maintenance records for 51 wood chippers operated by 48 chipping service contractors. Repair and maintenance represented between 1.5% and 29% of total chipping cost, inclusive of fuel and labour (mean = 14%). The ratio between total accumulated repair (TAR) cost and machine price averaged 32% and varied with total use. The relationship between total use and TAR to price ratio was explored through regression analysis, which produced a very strong model (R2 = 0.8). This model predicts a TAR to price ratio of 0.64 at 10000 h, with no significant differences between tractor-driven and independent-engine machines. While the coefficients are different, the structure of this model offers a good match with the repair and maintenance cost models developed for farm tractors and other agricultural machinery. A second model was developed for estimating repair and maintenance cost as a function of fuel consumption. The study also provides reference figures for the contribution of labour cost to total maintenance cost. Farm tractors incur more repairs than preventive maintenance, contrary to the other dedicated components of the chipping operation, where preventive maintenance represents most of maintenance cost. Forestry users should make allowance for the lower structural strength of tractors and select large models. Highlights • Long-term maintenance records were obtained for 51 wood chippers. • Maintenance is 14% of chipping cost on average, and ranges between 1.5 and 29%. • At 10000 h, total accumulated repair (TAR) cost amounted to 60% of machine price. • A model was developed for predicting TAR as a function of total use. • Maintenance was also estimated as a function of fuel consumption. [ABSTRACT FROM AUTHOR]

Abstract: This paper gives an overview of bioenergy use, prices, markets and markets prospects in Norway. The current energy production based on biomass in Norway is about 50pJ or 10% of the stationary energy consumption. About one-half is produced and used in forest industries. The main share of bioenergy used by households consists of firewood in stoves. The use of refined, solid biofuels in heat production is hampered by low coverage of water-borne heating systems and historically low end-user prices of electricity. Harvest levels in Norwegian forests are much below annual growth, implying that forest biomass resources steadily accumulate. Decreasing wood prices combined with rising prices of oil and electricity in recent year have improved competitiveness of solid biofuels in the heat market. Projections of future bioenergy use in Norway using a partial equilibrium forest sector model suggest that bioenergy use will increase in some market segments with the current price levels of electricity and oil. However, quite minor improvements of bioenergy competitiveness or increased energy prices may release substantially higher bioenergy use. A net increase in bioenergy use of 5TWh (18PJ 1 [1] 1TWh=3.6pJ. ) by 2010 is realistic, but requires public awareness of the opportunities in bioenergy technologies, as well as significant economic incentives. Wood stoves and replacement of oil-boilers in central heating systems show highest competitiveness, whereas district heating systems need higher energy prices or more subsidies to be competitive. Biomass for combined heat and power projects or domestically produced liquid biofuels seems to have limited competitiveness in the short term. On the raw material side, wood residues, and roundwood from pine and non-coniferous species represent the main potential, whereas spruce continues to be consumed by the forest industries. According to the model projections, imported biomass will take a significant share of the possible increase of wood consumption in Norway. [Copyright &y& Elsevier]