The Swedish wood fuel market

In Sweden, wood fuels are traditionally used in the Swedish forest products industry and for heating of single-family houses. More recently they are also become established as an energy source for district heating and electricity production. Energy policy, especially the energy taxation system, has favoured wood fuels and other biofuels, mainly for environmental reasons. There is now an established commercial market for wood fuels in the district heating sector, which amounts to 45 PJ and is growing 20 per cent annually. Price levels have been stable in current prices for a decade, mainly because of good access to wood fuels. Price levels are dominated by production costs on a market that is largely governed by the buyer.It is expected that the use of wood fuels will increase in Sweden in the future, which will push a further development of this sector on the market and bring about technological changes in the area.     

Price relationships and market integration in the Swedish wood fuel market

Cointegration analysis is applied to the prices of three different wood fuel assortments in the Swedish market: refined wood fuels, forest chips and industrial by-products. For the latter two, the price series are separated according to two consumer categories: district heating (DH) plants and industrial consumers. Two types of analyses are performed. The first concerns whether the fuels within each consumer group can be bundled together as belonging to the same market in terms of product homogeneity. The second involves analysis of the prices of homogeneous fuels in the two consumer categories. It is found that in the DH sector, refined wood fuels should be observed as a separate market because their prices do not share a common trend with the prices of any of the other fuels. This lack of a common trend is likely due to the highly internationalized nature of the wood pellet market. The DH prices of forest chips and industrial by-products follow a common trend, as do the prices paid for industrial by-products by DH plants and industrial consumers. The prices of forest chips paid by industrial consumers and DH plants do not share a common trend. The prices paid by industrial consumers for industrial by-products and forest chips also do not share a common trend. These results highlight both the differences between the markets for unrefined and refined wood fuels and the presence of inefficiencies in the Swedish wood fuel market.     

World trade in forest products and wood fuel

Wood fuel is a strategic resource for future energy supply and is usually utilised locally. Traditional use of wood fuel and other bioenergy has a share of 10–15% energy supply, used mainly for the household sector. The utilisation for industrial purposes is much smaller but is a strategic resource in the effort to fulfil the Kyoto agreement to replace fossil fuels and to mitigate greenhouse gas emissions. Many industrialised countries already use a significant share of biofuels in their energy supply e.g. Nordic countries while others like some other European Union countries are planning to increase their use. Production and use of biofuels need to be carried out sustainable. Official statistics do not report trade in such detail that international trade in different biomass types can be fully identified. However, FAO and European Forestry Institute are important sources. In some countries, there is a growing interest in the international trade, because the trade can provide biofuels at lower prices, larger quantities and better quality than domestic alternatives. The first signs of an international market price for wood fuel are indicated in Europe. For the future both the use and the trade of wood fuel is expected to increase. Analyses for trade in charcoal, wood chips, fuel wood and wood residues made in this report identify ‘hot’ trade spots in Europe, in south East Asia and in North America.     

Influence of fuel composition on chemiluminescence emission in premixed flames of CH4/CO2/H2/CO blends

The growing concern about pollutant emissions and depletion of fossil fuels has been a strong motivator for the development of cleaner and more efficient combustion strategies, such as the gasification of coal, biomass or waste, which have increased the interest in using a new type of fuels, mainly composed of CH₄, H₂, CO and CO₂.These new fuels, commonly called syngas, display a wide range of compositions, which affects their combustion characteristics and, in some cases, are more prone to instabilities or flashback. Since flame properties have been demonstrated to be strongly related to equivalence ratio, a precise measurement of the flame stoichiometry is a key pre-requisite for combustion optimization and prevention of unstable regimes. In particular, chemiluminescence emission from flames has been largely tested for stoichiometry monitoring for methane flames, but its use in syngas flames has been far less studied. Consequently, the main goal of this work is analyzing the effect of fuel composition on the chemiluminescence vs. equivalence ratio curves for different fuel blends, as a first approach for a wide range of syngas compositions. The experimental results revealed that the ratio OH*/CH*, which had been widely demonstrated to be the best option for methane, may not be suitable for monitoring with certain fuels, such as those with a high percent of hydrogen. Alternatively, other signals, in particular the ratio OH*/CO₂*, appear as viable stoichiometry indicators in those cases.The analysis was also completed by numerical predictions with CHEMKIN. The comparisons of calculations with different flame models and experimental data reveals differences in the chemiluminescence vs. equivalence ratio curves for the different combustion regimes, depending on the range of the equivalence ratio ranges and fuel compositions. This finding, which confirms previous observations for a much narrower range of fuels, could have important practical consequences for the application of the technique in real combustors.     

Contribution of fuel cell systems to CO2 emission reduction in their application fields

Fuel cells (FCs) and their hybrid systems can play a key role in reducing carbon dioxide (CO₂) emissions. The present paper analyzes the contributions of the FC system to CO₂ emission reduction in three application fields.In the mobile application field, the direct methanol FC system has little or no influence on CO₂ emission reduction.The benefit of the FC in CO₂ emission reduction in the transportation field is directly dependant on the H₂ production method. Pre-combustion technology (with carbon capture) represents one of the best mid-term solutions for H₂ production. If FC vehicles (FCVs) use the H₂ produced by this process, the CO₂ emissions in this field could be decreased to 70–80% of the traditional CO₂ emissions.In the stationary application field, the FC system can be effectively operated as the distributed generation (DG) in terms of CO₂ emission reduction. Among the various types of FC or FC hybrid system used for DG, the solid oxide FC (SOFC) hybrid system with a CO₂ capture unit is the best option as it doubled the electricity efficiency compared to the traditional combustion cycle and decreases the CO₂ emission to 13.4% of the traditional CO₂ emission.However, the FC and carbon capture and sequestration (CCS) technologies need to be fully developed before the FC can contribute to reducing CO₂ emissions.     

NO emission characteristics in counterflow diffusion flame of blended fuel of H2/CO2/Ar

Flame structure and NO emission characteristics in counterflow diffusion flame of blended fuel of H₂/CO₂/Ar have been numerically simulated with detailed chemistry. The combination of H₂, CO₂ and Ar as fuel is selected to clearly display the contribution of hydrocarbon products to flame structure and NO emission characteristics due to the breakdown of CO₂. A radiative heat loss term is involved to correctly describe the flame dynamics especially at low strain rates. The detailed chemistry adopts the reaction mechanism of GRI 2.11, which consists of 49 species and 279 elementary reactions. All mechanisms including thermal, NO₂, N₂O and Fenimore are taken into account to separately evaluate the effects of CO₂ addition on NO emission characteristics. The increase of added CO₂ quantity causes flame temperature to fall since at high strain rates a diluent effect is prevailing and at low strain rates the breakdown of CO₂ produces relatively populous hydrocarbon products and thus the existence of hydrocarbon products inhibits chain branching. It is also found that the contribution of NO production by N₂O and NO₂ mechanisms are negligible and that thermal mechanism is concentrated on only the reaction zone. As strain rate and CO₂ quantity increase, NO production is remarkably augmented. Copyright © 2002 John Wiley & Sons, Ltd.     

Decomposing changes in CO2 emission inequality over time: The roles of re-ranking and changes in per capita CO2 emission disparities

This paper analyzes the effects of changes in country ranking and per capita CO₂ emissions on the change in CO₂ emission inequality over time. For this purpose, we introduce a three-term decomposition of the change occurring in the Gini index of per capita CO₂ emissions when moving from an initial to a final per capita CO₂ emission distribution. The decomposition explains the link between the inequality trend and the changes in country ranking, population size, and per capita CO₂ emission disparities. We show that all components of inequality change can be further decomposed by subgroup. This provides analysts with a decomposition technique detecting the within-group and between-group contributions to each component of inequality change. The decomposition is used to analyze the change in per capita CO₂ emission inequality in Europe over the 1991–2011 period.     

The evolution of hard coal trade in the Pacific market

This article analyses the evolution of hard coal trade in the Asia Pacific region, known as the Pacific market, from the 1980s to the present years. It investigates the development of the trade pattern, the nature of contracts, the price setting, the supply demand and the future of trade.     

The evolution of hard coal trade in the Atlantic market

This article analyses the evolution of hard coal trade in West-Europe, known as the Atlantic market, from the 1980s to the end of 2002. It investigates the development of trade pattern, nature of contracts, price setting, supply–demand and the future of trade.     

The impact of coal consumption and CO2 emission on economic growth

This study examined the long-run and the causal relationship between total coal consumption, CO₂ emission, and GDP growth in China, the United States, India, Germany, Russia, South Africa, Japan, Australia, Poland, and South Korea. The panel model was employed during the period 1992–2009. The results showed that total coal consumption and CO₂ emission have a long-run relationship with the GDP growth. In addition, there was a short-run positive bidirectional causal relationship between total coal consumption and CO₂ emission. However, total coal consumption and CO₂ emission have no short-run or long-run causal relationship with GDP growth. Thus energy conservation policies on total coal consumption such as rationing energy consumption and controlling CO₂ emissions are likely to have no negative impact on the real output growth of the investigated countries.     

CO_2转化燃料技术

碳科学公司(Carbon Sciences)9月底宣布,正在开发将CO2转化为低碳烃类(C1～C3)的工艺,以便进一步制成高碳烃类燃料,如汽油和喷气燃料.     

Consumers in the green electricity market in Finland

“Green” electricity, i.e. electricity produced from environmentally less harmful sources and marketed as such, has been available to Finnish households since 1998, but the demand for it has remained low. In this paper we discuss the barriers identified by consumers to purchasing green electricity and contrast these with the interpretation energy sector actors give to consumer passivity. The empirical material consists of thematic interviews. Energy policy actors often assume that consumers’ passivity signifies their lack of interest or low environmental consciousness. This results partly from the failure to differentiate between the roles of consumer and citizen. The interpretation the energy sector actors give to consumer passivity and the role they assign to consumers affect the direction of green electricity policy. We argue that consumers need more information on both the environmental impact of different electricity products and in particular about the electricity supply and electricity contracts in a liberalised electricity market if they are to become active in the market.     

The effect of capillary-trapped CO2 on oil recovery and CO2 sequestration during the WAG process

This study investigated capillary-trapped CO₂ depending on the consideration of hysteresis effect in relative permeability for various water-alternation-gas (WAG) operating conditions to ascertain the oil production process. From the simulation results of CO₂ WAG flooding method, the trapped CO₂ led to prevent water-flow, in which CO₂ acts as a gas blocker near the well. It caused the injection pressure increase during water injection period. As the trapped CO₂ in pores increased, the reservoir pressure was also increased and maintained above minimum miscibility pressure (MMP). Ultimately, it was concluded that the reservoir was kept under miscible conditions throughout WAG process, reducing residual oil and increasing oil recovery.     

The market for kerojet fuel in the United States

This paper presents a structural model of the market for kerojet fuel in the United States. Upon empirical estimation, it demonstrates that more kerojet output is forthcoming as the price of kerojet increases relative to the price of other refined petroleum products. Imports of kerojet into the United States increase as the domestic price of kerojet increases relative to the world price. Finally, the quantity of kerojet demanded falls in a small, but perceptible, way as its price increases.     

The effect of internal air bleed on CO poisoning in a proton exchange membrane fuel cell

It is found that carbon monoxide (CO) poisoning could be mitigated by increasing only cathode backpressure for a proton exchange membrane fuel cell (PEMFC) with ultra-thin membranes (≤25 μm). This mitigation can be explained by a heterogeneous oxidation of CO on a Pt-Ru/C anode by the permeated O₂ which is known as “internal air bleed” in his paper. A steady-state model which accounts for this internal air bleed has been developed to model the Pt-Ru/C anode polarization data when 50 ppm CO in H₂ is used as anode feed gas. The modeling results show that the mitigation of CO poisoning by the internal air bleed even exists at ambient conditions for a PEMFC with an ultra-thin membrane. Therefore, the effect of internal air bleed must be considered for modeling fuel cell performance or anode polarization data if an ultra-thin membrane and a low level of CO concentration are used for a Pt-Ru/C anode. An empirical relationship between the amount of internal air bleed used for the mitigation of CO poisoning and the fraction of free Pt sites is provided to facilitate the inclusion of an internal air bleed term in the modeling of anode polarization and the fuel cell performance.     

The wood pellet market in Austria: A structural market model analysis

EU bioenergy policies and oil price hikes have resulted in a significant increase of installed pellet boilers for residential heating. Hence, European demand for wood pellets has been growing faster and more steadily than supply leading to rising market prices in recent years. This article presents an econometric analysis of demand and supply of wood pellets in the residential heating sector in Austria, one of the most dynamic markets for residential pellets. Annual and monthly time series data between 2000 and 2014 are used in a two-stage least-squares (2SLS) regression to estimate supply and demand elasticities of wood pellets. In all model specifications, pellets demand is found to be inelastic (from −0.66 to −0.76) and pellets supply unit-elastic (from 1.03 to 1.18). Thus, consumers are highly exposed to price changes resulting from supply shocks. Policies which support investments in pellet boilers will shift the demand of wood pellets and likely leading to higher prices for consumers.     

木质燃料发热量的研究

介绍了木质燃料发热量的实验结果,对计算木质燃料发热量的经验公式进行了修正,并分析了木质燃料中水分对发热量的影响。     

A comparative study of dynamic changes in CO2 emission performance of fossil fuel power plants in China and Korea

This paper aims to conduct a comparative study of the changes in CO₂ emission performance of state-owned fossil fuel power plants between China and Korea. For this purpose, we combine the concept of the metafrontier Malmquist productivity index and the non-radial directional distance function to develop a new index called the non-radial metafrontier Malmquist CO₂ emission performance index (NMMCPI). This new methodology allows for the incorporation of technological heterogeneities and slack variables into the previously introduced Malmquist CO₂ emission performance index (MCPI). The NMMCPI can be derived by solving several non-radial data envelopment analysis (DEA) models. The NMMCPI can be decomposed into an efficiency change (EC) index, a best-practice gap change (BPC) index, and a technology gap change (TGC) index. By fixing the non-energy inputs, we measure the pure CO₂ emission performance change. Based on the proposed indices, the comparative study between Chinese and Korean fossil fuel power industries is conducted for the 2005–2010 period. Empirical results indicate significant differences in terms of various decomposed CO₂ emission performance changes between China and Korea. Korean power plants demonstrate improvements in innovation, while Chinese power plants demonstrate a higher ability for technological leadership. Some related policy implications are also proposed based on the empirical results.