Land clearing and greenhouse gas emissions from Jatropha biofuels on African Miombo Woodlands

The paper investigates greenhouse gas (GHG) emissions from land use change associated with the introduction of large-scale Jatropha curcas cultivation on Miombo Woodland, using data from extant forestry and ecology studies about this ecosystem. Its results support the notion that Jatropha can help sequester atmospheric carbon when grown on complete wastelands and in severely degraded conditions. Conversely, when introduced on tropical woodlands with substantial biomass and medium/high organic soil carbon content, Jatropha will induce significant emissions that offset any GHG savings from the rest of the biofuel production chain. A carbon debt of more than 30 years is projected. On semi-degraded Miombo the overall GHG balance of Jatropha is found to hinge a lot on the extent of carbon depletion of the soil, more than on the state of the biomass. This finding points to the urgent need for detailed measurements of soil carbon in a range of Miombo sub-regions and similar tropical dryland ecosystems in Asia and Latin America. Efforts should be made to clarify concepts such as ‘degraded lands’ and ‘wastelands’ and to refine land allocation criteria and official GHG calculation methodologies for biofuels on that basis.     

A conceptual lignocellulosic ‘feed+fuel’ biorefinery and its application to the linked biofuel and cattle raising industries in Brazil

It has been argued by some that the substitution of biofuels for gasoline could increase greenhouse gas (GHG) emissions, rather than reduce them. The increase is attributed to the indirect land use change effects of planting new grain and corn crops around the world to replace those progressively being devoted to ethanol production. In this paper, indirect effects are minimised by allowing land to be used for both food and fuel, rather than for one or the other. We present a sugarcane ‘feed+fuel’ biorefinery, which produces bioethanol and yeast biomass, a source of single-cell protein (SCP), that can be used as a high-protein animal feed supplement. The yeast SCP can partially substitute for grass in the feed of cattle grazing on pasture and thereby potentially release land for increased sugarcane production, with minimal land use change effects. Applying the concept conservatively to the Brazilian ethanol and livestock industry our model demonstrates that it would be technically feasible to raise ethanol production threefold from the current level of 27 GL to over 92 GL. The extra ethanol would meet biofuel market mandates in the US without bringing any extra land into agricultural or pastoral use. The analysis demonstrates a viable way to increase biofuel and food production by linking two value chains as called for by industrial ecology studies.     

Consequential effects of increased biofuel demand in Spain: Global crop area and CO2 emissions from indirect land use change

The indirect Land Use Change (iLUC) impacts of biofuels refer to the effects of additional emissions due to land-use changes triggered by the expansion of energy crops in response to increased biofuel demand. These emissions are mostly greenhouse gases (GHG), thus relevant to the climate change impact category. In order to address these effects, the European Commission (EC) has proposed the inclusion of feedstock type specific iLUC factors for different biofuel sources in the Renewable Energy Sources Directive 2009/28/EC (RED). The goal of this study is to quantify the indirect environmental impacts both in terms of global energy crop land area and the subsequent iLUC, if an additional demand of biofuel in Spain occurs, from a consequential approach. Results show a wide range of GHG emissions, in terms of CO₂, of biodiesel and bioethanol from iLUC effects, strongly influenced by the place where the potential biofuel is produced. Based on our study, two main aspects -determine the iLUC effects: the dedicated energy crops that are used to produce biofuels and the different coproducts obtained along the biofuels production process. Therefore, contrary to the EC proposal for including a single factor by type of crop, the development of origin-dependent iLUC factors seems to be a more appropriate alternative based on the current assessment. Other aspects that might affect the results, such as crop rotation or field management, have been excluded from the analysis in this work.     

How much hope should we have for biofuels?

This paper revisits the recent developments in biofuel markets and their economic, social and environmental impacts. Several countries have introduced mandates and targets for biofuel expansion. Production, international trade and investment have increased sharply in the last few years. However, some analysts linked biofuels to the 2007-2008 global food crisis. Existing studies diverge on the magnitude of the projected long-term impacts of biofuels on food prices and supply, with studies that model only the agricultural sector showing higher impacts and studies that model the entire economy showing relatively lower impacts. In terms of climate change mitigation, biofuels reduces GHG emissions only if GHG emissions related to land-use change are avoided. When biofuel production entails conversion of forest to cropland, net reduction of GHG would not be realized for many years. Existing literature does not favor the diversion of food for large-scale biofuels production, but the regulated expansion of biofuels in countries with surplus lands and a strong biofuel industry cannot be ruled out. Developments in non-food based or cellulosic (or second generation) biofuels may offer some hope, yet they still compete with food supply through land use and are currently constrained by a number of technical and economic barriers.     

Biofuels and their potential to aid the UK towards achieving emissions reduction policy targets

The potential of biofuels contributing to the UK emission reduction targets in the formulated UK Low Carbon Transition Plan (LCTP) and the UK’s obligation in the wider EU emissions reduction targets are assessed using four scenarios. The scenarios were evaluated using hybrid lifecycle assessment developed in a multi-regional input–output (MRIO) framework. In the hybrid MRIO LCA framework, technology-specific processes in the biofuels and fossil fuels LCA systems are integrated into a generalised 2-region (UK and Rest of the World) environmental-economic input–output framework in order to account for economy-wide indirect GHG emissions in the biofuels and fossil fuels LCA systems in addition to other indirect impacts such as indirect land use change. The lifecycle greenhouse gas emissions of biodiesel (soybean, palm, rape, waste cooking oil) and bio-ethanol (sugarcane, sugarbeet, corn) were assessed and compared to fossil fuel (diesel and petrol) baseline. From one of the scenarios, biodiesel production from waste cooking oil and bioethanol from sugarbeet offer the biggest potential for emissions savings relative to fossil fuel equivalent and offering a maximum emission savings of 4.1% observed with a biofuel market share of 10% reached in 2020. It was also established that under current biofuel feedstock mix, to achieve the 6% emissions saving primarily from biofuels as proposed in the LCTP, 23.8% of the transport fuels market would be required to be held by biofuels by 2020.     

The GHG balance of biofuels taking into account land use change

The contribution of biofuels to the saving of greenhouse gas (GHG) emissions has recently been questioned because of emissions resulting from land use change (LUC) for bioenergy feedstock production. We investigate how the inclusion of the carbon effect of LUC into the carbon accounting framework, as scheduled by the European Commission, impacts on land use choices for an expanding biofuel feedstock production. We first illustrate the change in the carbon balances of various biofuels, using methodology and data from the IPCC Guidelines for National Greenhouse Gas Inventories. It becomes apparent that the conversion of natural land, apart from grassy savannahs, impedes meeting the EU's 35% minimum emissions reduction target for biofuels. We show that the current accounting method mainly promotes biofuel feedstock production on former cropland, thus increasing the competition between food and fuel production on the currently available cropland area. We further discuss whether it is profitable to use degraded land for commercial bioenergy production as requested by the European Commission to avoid undesirable LUC and conclude that the current regulation provides little incentive to use such land. The exclusive consideration of LUC for bioenergy production minimizes direct LUC at the expense of increasing indirect LUC.     

A life cycle assessment of pennycress (Thlaspi arvense L.) -derived jet fuel and diesel

Field Pennycress (Thlaspi arvense L.) is a member of the mustard family and may be grown as a winter crop between traditional summer crops to produce renewable biomass for renewable diesel and jet fuel. This paper estimated total annual biofuel production potential of 15 million cubic metres from rotation between corn and soybeans on 16.2 million hectares in the Midwest without impact on food production. This study also investigated the life cycle greenhouse gas (GHG) emissions and energy balance of pennycress-derived Hydroprocessed Renewable Jet (HRJ) fuel and Renewable Diesel (RD). Both system expansion and allocation approaches were applied to distribute environmental impacts among products and co-products along the life cycle of each biofuel. The life cycle GHG emissions (excluding land use change) for RD and HRJ range from 13 to 41 g MJ⁻¹ (CO₂ eq.) and −18 to 45 g MJ⁻¹ (CO₂ eq.), respectively, depending on how the co-products are credited. The majority of the energy required for each biofuel product is derived from renewable biomass as opposed to non renewable fossil. The fossil energy consumptions are considerably lower than the petroleum fuels. Scenario analyses were also conducted to determine response to model assumptions, including nitrogen fertilizer application rate, nitrogen content in crop residues, and sources of H₂. The results show that pennycress derived biofuels could qualify as advanced biofuels and as biomass-based diesel as defined by the Renewable Fuels Standard (RFS2).     

Life cycle greenhouse gas emissions impacts of the adoption of the EU Directive on biofuels in Spain. Effect of the import of raw materials and land use changes

The objective of this paper is to evaluate the greenhouse gas (GHG) emissions impacts of the use of different alternative biofuels in passenger vehicles in Spain in order to meet EU biofuel goals. Different crop production alternatives are analysed, including the possible import of some raw materials. Availability of land for national production of the raw materials is analysed and indirect land use changes and associated GHG emissions are quantified.There are important differences in GHG emissions of biofuels depending on the raw material used and whether this is domestically produced or imported. Ethanol production using imported cereals and FAME production using domestic rapeseed have the highest GHG emissions per kilometre driven. Fatty acid methyl ester (FAME) production from sunflower has shown the lowest emissions. When taking into account the results of GHG emissions savings per hectare, these findings are somehow reversed. Production of ethanol and around 12% of FAME can be done domestically. The rest will need to be imported and will cause indirect land use change (ILUC). Therefore, ethanol production will not displace any land, whereas FAME production will displace some amounts of land. Calculated ILUC factors are 29%-34%. The additional GHG emissions due to these indirect land use changes are significant (67%-344% of life cycle GHG emissions).Standalone, the EU biofuel targets can have important benefits for Spain in terms of global warming emissions avoided. However, when considering the impact of land use change effects, these benefits are significantly reduced and can even be negative.     

Biofuel production and implications for land use,food production and environment in India

There is a large interest in biofuels in India as a substitute to petroleum-based fuels, with a purpose of enhancing energy security and promoting rural development. India has announced an ambitious target of substituting 20% of fossil fuel consumption by biodiesel and bioethanol by 2017. India has announced a national biofuel policy and launched a large program to promote biofuel production, particularly on wastelands: its implications need to be studied intensively considering the fact that India is a large developing country with high population density and large rural population depending upon land for their livelihood. Another factor is that Indian economy is experiencing high growth rate, which may lead to enhanced demand for food, livestock products, timber, paper, etc., with implications for land use. Studies have shown that area under agriculture and forest has nearly stabilized over the past 2–3 decades. This paper presents an assessment of the implications of projected large-scale biofuel production on land available for food production, water, biodiversity, rural development and GHG emissions. The assessment will be largely focused on first generation biofuel crops, since the Indian program is currently dominated by these crops. Technological and policy options required for promoting sustainable biofuel production will be discussed.     

GHG sustainability compliance of rapeseed-based biofuels produced in a Danish multi-output biorefinery system

Biofuels are likely to play an increasingly important role in the transportation sector in the coming decades. To ensure the sustainability of the biofuel chain, regulatory criteria and reduction targets for greenhouse gases (GHG) emissions have been defined in different legislative frameworks (e.g. the European Renewable Energy Directive, RED). The provided calculation methods, however, leave room for interpretation regarding methodological choices, which could significantly affect the resulting emission factors. In this study, GHG reduction factors for a range of biofuels produced in a Danish biorefinery system were determined using five different emission allocation principles. The results show that emission savings ranged from −34 % to 71 %, indicating the need for a better definition of regulatory calculation principles. The calculated emission factors differed significantly from default values provided in the literature, suggesting that case-specific local conditions should be taken into consideration. A more holistic LCA-based approach proved useful in overcoming some of the issues inherent in the regulatory allocation principles. On this basis, indirect land use change (ILUC) emissions were shown to have the same magnitude as the direct emissions, thus indicating that the overall system should be included when assessing biofuel sustainability criteria.     

The impact of oil prices on bioenergy,emissions and land use

We evaluate how alternative future oil prices will influence the penetration of biofuels, energy production, greenhouse gas (GHG) emissions, land use and other outcomes. Our analysis employs a global economy wide model and simulates alternative oil prices out to 2050 with and without a price on GHG emissions. In one case considered, based on estimates of available resources, technological progress and energy demand, the reference oil price rises to $124 by 2050. Other cases separately consider constant reference oil prices of $50, $75 and $100, which are targeted by adjusting the quantity of oil resources. In our simulations, higher oil prices lead to more biofuel production, more land being used for bioenergy crops, and fewer GHG emissions. Reducing oil resources to simulate higher oil prices has a strong income effect, so decreased food demand under higher oil prices results in an increase in land allocated to natural forests. We also find that introducing a carbon price reduces the differences in oil use and GHG emissions across oil price cases.     

Global land-use implications of first and second generation biofuel targets

Recently, an active debate has emerged around greenhouse gas emissions due to indirect land use change (iLUC) of expanding agricultural areas dedicated to biofuel production. In this paper we provide a detailed analysis of the iLUC effect, and further address the issues of deforestation, irrigation water use, and crop price increases due to expanding biofuel acreage. We use GLOBIOM – an economic partial equilibrium model of the global forest, agriculture, and biomass sectors with a bottom-up representation of agricultural and forestry management practices. The results indicate that second generation biofuel production fed by wood from sustainably managed existing forests would lead to a negative iLUC factor, meaning that overall emissions are 27% lower compared to the “No biofuel” scenario by 2030. The iLUC factor of first generation biofuels global expansion is generally positive, requiring some 25 years to be paid back by the GHG savings from the substitution of biofuels for conventional fuels. Second generation biofuels perform better also with respect to the other investigated criteria; on the condition that they are not sourced from dedicated plantations directly competing for agricultural land. If so, then efficient first generation systems are preferable. Since no clear technology champion for all situations exists, we would recommend targeting policy instruments directly at the positive and negative effects of biofuel production rather than at the production itself.     

Which is the preferable transport fuel on a greenhouse gas basis; biomethane or ethanol?

Biomethane and ethanol are both biofuels which are generated from agricultural crops that can be utilised to meet the Biofuels Directive. In Ireland with the demise of the sugar industry 48,000 Ha of land is readily available for biofuel production, without unduly effecting food production. Which biofuel should dominate? This paper investigates biofuel production for three different crop rotations: wheat, barley and sugar beet; wheat, wheat and sugar beet; wheat only. A greenhouse gas balance is performed to determine under what conditions each biofuel is preferable. For both biofuels, the preferred crop on a weight basis is wheat, while on an area basis the preferred crop is sugar beet. Biomethane scenarios produce more gross energy than ethanol scenarios. Under the base assumption (7.41% biogas losses, and biomethane utilised in a converted petrol engine, such as a bi-fuel car, and thus underperforming on a km/MJ basis) ethanol generated more net greenhouse gas savings than biomethane. This was unexpected as biomethane produces twice the net energy per hectare as ethanol. If either biogas losses were reduced or biomethane was utilised in a vehicular engine optimised for biomethane (such as a bus powered solely on gaseous biofuel) then biomethane would generate significantly more net greenhouse gas savings than ethanol. It was found that if biogas losses were eliminated and the biomethane was used in a vehicle optimised for biomethane, then the net greenhouse gas savings are 2.4 times greater than those from ethanol generated from the same feedstock.     

Reduction potentials of energy demand and GHG emissions in China's road transport sector

Rapid growth of road vehicles, private vehicles in particular, has resulted in continuing growth in China's oil demand and imports, which has been widely accepted as a major factor effecting future oil availability and prices, and a major contributor to China's GHG emission increase. This paper is intended to analyze the future trends of energy demand and GHG emissions in China's road transport sector and to assess the effectiveness of possible reduction measures. A detailed model has been developed to derive a reliable historical trend of energy demand and GHG emissions in China's road transport sector between 2000 and 2005 and to project future trends. Two scenarios have been designed to describe the future strategies relating to the development of China's road transport sector. The ‘Business as Usual’ scenario is used as a baseline reference scenario, in which the government is assumed to do nothing to influence the long-term trends of road transport energy demand. The ‘Best Case’ scenario is considered to be the most optimized case where a series of available reduction measures such as private vehicle control, fuel economy regulation, promoting diesel and gas vehicles, fuel tax and biofuel promotion, are assumed to be implemented. Energy demand and GHG emissions in China's road transport sector up to 2030 are estimated in these two scenarios. The total reduction potentials in the ‘Best Case’ scenario and the relative reduction potentials of each measure have been estimated.     

Strategies for 2nd generation biofuels in EU – Co-firing to stimulate feedstock supply development and process integration to improve energy efficiency and economic competitiveness

The present biofuel policies in the European Union primarily stimulate 1st generation biofuels that are produced based on conventional food crops. They may be a distraction from lignocellulose based 2nd generation biofuels – and also from biomass use for heat and electricity – by keeping farmers' attention and significant investments focusing on first generation biofuels and the cultivation of conventional food crops as feedstocks. This article presents two strategies that can contribute to the development of 2nd generation biofuels based on lignocellulosic feedstocks. The integration of gasification-based biofuel plants in district heating systems is one option for increasing the energy efficiency and improving the economic competitiveness of such biofuels. Another option, biomass co-firing with coal, generates high-efficiency biomass electricity and reduces CO₂ emissions by replacing coal. It also offers a near-term market for lignocellulosic biomass, which can stimulate development of supply systems for biomass also suitable as feedstock for 2nd generation biofuels. Regardless of the long-term priorities of biomass use for energy, the stimulation of lignocellulosic biomass production by development of near term and cost-effective markets is judged to be a no-regrets strategy for Europe. Strategies that induce a relevant development and exploit existing energy infrastructures in order to reduce risk and reach lower costs, are proposed an attractive complement the present and prospective biofuel policies.     

Resource use efficiency and environmental performance of nine major biofuel crops,processed by first-generation conversion techniques

We compared the production–ecological sustainability of biofuel production from several major crops that are also commonly used for production of food or feed, based on current production practices in major production areas. The set of nine sustainability indicators focused on resource use efficiency, soil quality, net energy production and greenhouse gas emissions, disregarding socio-economic or biodiversity aspects and land use change. Based on these nine production–ecological indicators and attributing equal importance to each indicator, biofuel produced from oil palm (South East Asia), sugarcane (Brazil) and sweet sorghum (China) appeared most sustainable: these crops make the most efficient use of land, water, nitrogen and energy resources, while pesticide applications are relatively low in relation to the net energy produced. Provided there is no land use change, greenhouse gas emissions of these three biofuels are substantially reduced compared with fossil fuels. Oil palm was most sustainable with respect to the maintenance of soil quality. Maize (USA) and wheat (Northwest Europe) as feedstock for ethanol perform poorly for nearly all indicators. Sugar beet (Northwest Europe), cassava (Thailand), rapeseed (Northwest Europe) and soybean (USA) take an intermediate position.     

Possible impact of the Renewable Energy Directive on N fertilization intensity and yield of winter oilseed rape in different cropping systems

In 2009, the Renewable Energy Directive (RED), established sustainability criteria for biofuels including legal thresholds for specific greenhouse gas (GHG) emissions, expressed as g CO₂eq per MJ of biofuel. Because biofuels are a major market for winter oilseed rape (WOSR), investigating the possible impact of the RED on WOSR cropping practices is prudent. This study analyses GHG emissions for WOSR cropping practices (namely N fertilization intensity, tillage method and crop rotation) basing on a 6-year field trial in a high yielding area of northern Germany. Using the International Panel on Climate Change (IPCC) methodology the field emissions of nitrous oxide (N₂O) are calculated from the nitrogen (N) inputs to the cropping system.Results showed that the predominant source of GHG emissions is the N related emissions from production of fertilizer and N₂O field emissions. Specific GHG emissions are lowest without N fertilizer but rise continuously with increasing N rates. Yield per ha also responded to N fertilization resulting in lowered acreage productivity when reducing GHG emissions by reducing N fertilization level. Most calculated scenarios and cropping systems result in a drastic decrease of N fertilization to achieve thresholds, causing substantial yield losses. To a certain extent, the required drastic reduction of N fertilization in some scenarios is driven by using the IPCC methodology for calculating N₂O emissions. Therefore characteristics of this methodology are also discussed within this study. To mitigate the impact of the RED on WOSR, peas (legumes) may be a possible preceding crop to WOSR.     

Biofuels versus food production: Does biofuels production increase food prices?

Rapidly growing fossil energy consumption in the transport sector in the last two centuries caused problems such as increasing greenhouse gas emissions, growing energy dependency and supply insecurity. One approach to solve these problems could be to increase the use of biofuels.Preferred feedstocks for current 1st generation biofuels production are corn, wheat, sugarcane, soybean, rapeseed and sunflowers. The major problem is that these feedstocks are also used for food and feed production.The core objective of this paper is to investigate whether the recent increase of biofuels production had a significant impact on the development of agricultural commodity (feedstock) prices. The most important impact factors like biofuels production, land use, yields, feedstock and crude oil prices are analysed.The major conclusions of this analysis are: In recent years the share of bioenergy-based fuels has increased moderately, but continuously, and so did feedstock production, as well as yields. So far, no significant impact of biofuels production on feedstock prices can be observed. Hence, a co-existence of biofuel and food production seems possible especially for 2nd generation biofuels. However, sustainability criteria should be seriously considered. But even if all crops, forests and grasslands currently not used were used for biofuels production it would be impossible to substitute all fossil fuels used today in transport.     

GHG balances of bioenergy systems – Overview of key steps in the production chain and methodological concerns

This paper deals with a methodology for calculating the greenhouse gas (GHG) balances of bioenergy systems producing electricity, heat and transportation biofuels from biomass residues or crops. Proceeding from the standard Life-Cycle Assessment (LCA) as defined by ISO 14040 norms, this work provides an overview of the application of the LCA methodology to bioenergy systems in order to estimate GHG balances. In this paper, key steps in the bioenergy chain are identified and the bioenergy systems are compared with fossil reference systems producing the same amount of final products/services. The GHG emission balances of the two systems can thus be compared. Afterwards, the most important methodological assumptions (e.g. functional unit, allocation, reference system, system boundaries) and key aspects affecting the final outcomes are discussed. These key aspects are: changes in organic carbon pools, land-use change effects (both direct and indirect), N₂O and CH₄ emissions from agricultural soils and effects of crop residue removal for bioenergy use. This paper finally provides some guidelines concerning the compilation of GHG balances of bioenergy systems, with recommendations and indications on how to show final results, address the key methodological issues and give homogenous findings (in order to enhance the comparison across case studies).     

Insights into biofuel development in Burkina Faso: Potential and strategies for sustainable energy policies

In many African countries, the upswing in oil prices is one factor that favours the adoption and implementation of a national biofuel policy. This trend has a major impact on state budgets and domestic trade balances, while also limiting the access of rural inhabitants to modern energy services. Contribution of biofuels in stabilizing the energy sector, influences ongoing negotiations on the global dynamics of climate change, the reduction in greenhouse gas (GHG) emissions and sustainable development. The question of biofuels as an alternative energy thus depends on international, national and local considerations. Biofuels represent opportunities, e.g., energy independence and security, new national income and employment sources, as well as potential food security problems. African policy makers therefore need to make the right choices to guide the development of biofuel production and use.This article aims to support the development of a biofuel policy by reviewing the latest technical, economic, environmental and social knowledge so as to be able to evaluate the potential and limits of biofuels in Burkina Faso.