Biofuels from algae: technology options, energy balance and GHG emissions: Insights from a literature review

During the last decade(s), algal biomass received increasing interest as a potential source of advanced biofuels production resulting in a considerable attention from research, industry and policy makers. In fact, algae are expected to offer several advantages compared to land-based biomass crops, including: better photosynthetic efficiency; higher oil yield; growth on non-fertile land; tolerance to a variety of water sources (i.e. fresh, brackish, saline) and CO2 re-using potential. The algal growth can be also integrated in wastewater (WW) treatment systems to combine the nutrient streams removal with biofuels production. In addition, a wide range of marketable co-products can be extracted from algae (e.g. chemicals, pharmaceuticals, nutritionals) along with the production of biofuels, under a biorefinery system. Considering the potential benefits, several European-funded pilot projects, under science-business partnerships, have been dedicated to the development of algae technologies in the biofuels and bioenergy sectors. Despite the extensive research and investments in the last decade(s), no large-scale, commercial algae-to-biofuels facilities were implemented yet. In fact, in the current algae cultivation sites, the produced biomass is currently exploited for production of food and feed, combined with the extraction of high added-value products, such as proteins, nutritional supplements and chemicals. We report on the current-status of technology options for the potential exploitation of algae (of both macro- and microalgae species) in the biofuels and bioenergy sectors. We presents a comprehensive review of recent advances on promising algal biofuel production pathways, in terms of technological development, opportunities and limitations to their overall effectiveness. Furthermore, we analyse the main features, assumptions, modelling approaches and results of the algal biofuel pathways considered in the LCA literature. We highlight and interpret the energy and greenhouse gas (GHG) emissions balances resulting from examined LCA studies, in view of the key parameters mainly affecting the results. A comparison of the performance associated to the proposed algal biofuels pathways with that found for conventional fossil derived fuels is also reported.JRC.F.8-Sustainable Transpor

Solid and gaseous bioenergy pathways: input values and GHG emissions

The Renewable Energy Directive (RED) (2009/28/EC) and the Fuel Quality Directive (FQD) (2009/30/EC) fix a threshold of savings of greenhouse gas (GHG) emissions for biofuels and bioliquids, and set the rules for calculating the greenhouse impact of biofuels, bioliquids and their fossil fuels comparators. To help economic operators to declare the GHG emission savings of their products, default and typical values are also listed in the annexes of the RED and FQD directives. The Commission recommended Member States to use the same approach for other bioenergy sources in the report from the Commission to the Council and the European Parliament on sustainability requirements for the use of solid and gaseous biomass sources in electricity, heating and cooling (COM(2010)11). Typical and default GHG emission values for solid and gaseousbioenergy pathways were reported in the report. SWD(2014)2014 updates the values defined in the COM(2010)11 to account for the technogical and market developments in the bioenergy sector. This report describes the assumptions made by the JRC when compiling the updated data set used to calculate default and typical GHG emissions for the different solid and gaseous bioenergy pathways and the results of such calculations in terms of typical and default GHG emission values . In the annexes the comments/questions received from JRC as reaction to the presentation of the data in stakeholders/experts consultations are reported together with their relative answers/rebuttals. This report describes the assumptions made by the JRC when compiling the updated data set used to calculate default and typical GHG emissions for the different solid and gaseous bioenergy pathways and the results of such calculations in terms of typical and default GHG emission values . In the annexes the comments/questions received from JRC as reaction to the presentation of the data in stakeholders/experts consultations are reported together with their relative answers/rebuttals.JRC.F.8-Sustainable Transpor

Solid and gaseous bioenergy pathways: input values and GHG emissions: Calculated according to methodology set in COM(2016) 767: Version 2

The Commission's legislative proposal for a recast of the Renewable Energy Directive (RED-recast) (COM(2016) 767), in Art. 26(7), specifies the minimum greenhouse gas (GHG) emissions saving thresholds that bioenergy must comply with in order to count towards the renewables targets and to be eligible for public support. Annex V (liquid biofuels) and Annex VI (solid and gaseous biomass) of the RED-Recast describe the methodology for GHG savings calculations needed to comply with the GHG criteria. They also provide a list of Default GHG emission values, aggregated and disaggregated, that operators can use to demonstrate compliance of their product with the GHG criteria. This report describes the input data, assumptions and methodological approach applied by the JRC when compiling the updated dataset used to calculate GHG emissions for the different biomass pathways. The GHG emissions resulting from the application of the methodology from COM(2016) 767, and presented in Annex VI of the document, are also shown. The report aims to provide operators, stakeholders ,and the scientific community all the necessary information to explain the assumptions chosen as well as to guarantee reproducibility of the results. Additional analysis to test the sensitivity of the results to various assumptions is presented in the final section of the report.JRC.C.4-Sustainable Transpor

Domestic heating from forest logging residues: environmental risks and benefits

The European Union (EU) relies largely on bioenergy to achieve its climate and energy targets for 2020 and beyond. Special focus is placed on utilization of biomass residues, which are considered to cause low environmental impacts. We used the dataset from the latest European Commission document on the sustainability of solid and gaseous biomass (SWD2014 259), complementing those results by: i) designing three pathways for domestic-heat production using forest logging residues, with different combustion technologies; ii) expanding the analysis to include forest carbon stock development with and without bioenergy; iii) using absolute climate metrics to assess the surface temperature response by the end of the century to a bioenergy and a reference fossil system; iv) including multiple climate forcers (well-mixed GHG, near term climate forcers and surface albedo change); iv) quantifying life cycle impacts on acidification, particulate matter emissions and photochemical ozone formation; v) reviewing potential risks for forest ecosystem degradation due to increased removal of residues. Supply-chain GHG savings of the three pathways analysed ranged between 80% and 96% compared to a natural gas system, above the 70% threshold suggested by the EU. However, the climate impact of bioenergy should be assessed by considering also the non-bioenergy uses of the biomass and by including all climate forcers. We calculate the Surface Temperature Response to bioenergy and fossil systems by means of Absolute Global surface Temperature Potential (AGTP) metric. Domestic heating from logging residues is generally beneficial to mitigate the surface temperature increase by 2100 compared to the use of natural gas and other fossil sources. As long as residues with a decay rate in the forest higher than 2.7%*yr1 are considered as feedstock, investing now in the mobilization of residues for heat production can reduce the temperature increase by 2100 compared to all the fossil sources analysed, both in case of bioenergy as a systemic change or in case of bioenergy as a transitory option. Furthermore, several environmental risks are associated with the removal and use of forest logging residues for bioenergy. These issues concern mostly local air pollution, biodiversity loss and, mainly for stumps removal, physical damage to forest soils. Forest logging residues are not free of environmental risks. Actions promoting their use should consider: (i) that climate change mitigation depends mainly on the decay rate of biomass under natural decomposition and time and rate of technology deployment, (ii) whether management guidelines aimed at protecting long-term forest productivity are in place and (iii) whether proper actions for the management of adverse effects on local air pollution are in place

Climate change impacts of power generation from residual biomass

The European Union relies largely on bioenergy to achieve its climate and energy targets for 2020 and beyond. We assess, using Attributional Life Cycle Assessment (A-LCA), the climate change mitigation potential of three bioenergy power plants fuelled by residual biomass compared to a fossil system based on the European power generation mix. We study forest residues, cereal straws and cattle slurry. Our A-LCA methodology includes: i) supply chains and biogenic-CO2 flows; ii) explicit treatment of time of emissions; iii) instantaneous and time-integrated climate metrics. Power generation from cereal straws and cattle slurry can provide significant global warming mitigation by 2100 compared to current European electricity mix in all of the conditions considered. The mitigation potential of forest residues depends on the decay rate considered. Power generation from forest logging residues is an effective mitigation solution compared to the current EU mix only in conditions of decay rates above 5.2% a−1. Even with faster-decomposing feedstocks, bioenergy temporarily causes a STR(i) and STR(c) higher than the fossil system. The mitigation potential of bioenergy technologies is overestimated when biogenic-CO2 flows are excluded. Results based solely on supply-chain emissions can only be interpreted as an estimation of the long-term (>100 years) mitigation potential of bioenergy systems interrupted at the end of the lifetime of the plant and whose carbon stock is allowed to accumulate back. Strategies for bioenergy deployment should take into account possible increases in global warming rate and possible temporary increases in temperature anomaly as well as of cumulative radiative forcing

Proving the climate benefit in the production of biofuels from municipal solid waste refuse in Europe

The non-recyclable fraction of municipal solid waste (MSW refuse) represents over half of the total MSW production in Europe, with an energetic potential of 1250 PJ/year, a similar quantity to the current potential for energy production from agricultural residues. Currently, there are no alternative uses for MSW refuse other than landfilling or incineration. Thus, it represents an important untapped resource for biofuel production in Europe. Standard attributional LCAs have not been able to capture some of the bioenergy interactions with the climate system and neither to properly assess the climate change mitigation potential of bioenergy technologies. This study aims to fill this gap and properly assess the impact of the production of biofuels from MSW refuse on climate change by applying several methodological improvements in a time-dependent assessment, i.e., an explicit consideration of biogenic carbon flows using a dynamic LCA and an absolute formulation of the cumulative and instantaneous climate metrics. Two diverging examples of current MSW management systems are selected as references against which to assess the potential climate benefit of biofuel production: with or without dominant landfill disposal and with high or low GHG emissions from the power generation sector. The results show that in countries with current negligible landfilling, the production of biofuels would lead to a clear climate benefit. For landfill-dominant countries, the climate benefit would only be temporarily achieved in the medium term as the impact of landfills on climate decreases in the long term. However, considering a progressive banning of landfilling promoted by other policies for environmental protection and resource efficiency, the results would become positive for both countries with climate change mitigation guaranteed by using MSW refuse for biofuel production.Ministerio de Economía y Competitividad ENE2012-3159

Economics of GHG emissions mitigation via biogas production from Sorghum, maize and dairy farm manure digestion in the Po valley

AbstractThe Greenhouse gas (GHG) emissions and economic feasibility of electricity production from the anaerobic digestion of different substrates are studied in this paper. Three realistic substrate options for the climatic and soil conditions of a modelled farm in the Po Valley in Italy are analysed: manure from a dairy farm, Sorghum and maize.A detailed cost analysis is performed with field data provided by farmers and suppliers and literature sources. The capital costs (CAPEX) and the operational costs (OPEX), disaggregated by their components, are presented. Investment payback time is then calculated for the different substrates and technologies, while taking into account the Italian government feed-in tariff scheme for biogas plants implemented in 2013.In the specific conditions assumed, electricity production via anaerobic digestion of manure and co-digestion of manure with at most 30% Sorghum (no till) provide both GHG savings (in comparison to the Italian electricity mix) and profit for economic operators.The anaerobic digestion of silage maize or Sorghum alone, instead, provides no (or very limited) GHG savings, and, with the current feed-in tariffs, generates economic losses.Both economic and environmental performance are improved by the following practices: cultivating Sorghum instead of maize; implementing no till agriculture; and installing gas-tight tanks for digestate storage. A tool allowing a customised calculation of the economic performances of biogas plants is provided

Definition of input data to assess GHG default emissions from biofuels in EU legislation: Version 1c - July 2017

The Renewable Energy Directive (RED) (2009/28/EC) and the Fuel Quality Directive (FQD) (2009/30/EC), amended in 2015 by Directive (EU) 2015/1513 (so called ‘ILUC Directive’), fix a minimum requirement for greenhouse gas (GHG) savings for biofuels and bioliquids for the period until 2020, and set the rules for calculating the greenhouse impact of biofuels, bioliquids and their fossil fuels comparators. To help economic operators to declare the GHG emission savings of their products, default and typical values for a number of spefic pathways are listed in the annexes of the RED and FQD. The EC Joint Research Center (JRC) is in charge of defining input values to be used for the calculation of default GHG emissions for biofuels, bioliquids, solid and gaseous biomass pathways. An update of the GHG emissions in Annex V has been carried out for the new Proposal of a Directive on the Promotion of the Use of Energy from Renewable Sources (COM(2016)767 - RED-2), for the post-2020 framework. This report describes the assumptions made by the JRC when compiling the new updated data set used to calculate default and typical GHG emissions for the different biofuels pathways as proposed in the new RED-2 document.JRC.C.4-Sustainable Transpor

Brief on the use of Life Cycle Assessment (LCA) to evaluate environmental impacts of the bioeconomy

This brief on the use of Life Cycle Assessment (LCA) to evaluate environmental impacts of the bioeconomy is one out of a series of briefs from the EC's Knowledge Centre for Bioeconomy which intend to provide independent evidence for EU policy in this field. The following are the key results: 1. Potential environmental impacts of bioeconomy sectors and the use of bio-based commodities must be monitored, evaluated and forecast in order to ensure that the bioeconomy operates within safe ecological limits. 2. LCA is a structured, comprehensive and internationally standardised method used to assess potential environmental impacts associated with a product’s life cycle. 3. Different modelling principles allow for the development of approaches suited to a broad range of contexts and scales. The LCA modelling approach should carefully consider the goal and scope of the assessment in order to avoid misinterpretation of the results. Benchmarking products, checking compliance with regulatory requirements and evaluating the impacts of strategic decisions may require different approaches. 4. LCA that supports the implementation of policies should be easy to calculate, have well-defined rules, use a well-defined inventory and be of general validity across temporal and spatial scales. Elements of consequential thinking will benefit LCA that supports impact assessment of strategic policies. 5. An open database with attributional LCA results for bio-based commodities, calculated or assembled by the JRC is available. The updated Bioeconomy Strategy will help generate more and higher quality data. 6. Despite the uncertainties and limitations, life-cycle-based approaches provide the most comprehensive, structured, consistent and robust means of assessing the environmental performance of bio-based products and systems within safe ecological limits.JRC.D.1-Bio-econom

Exploring new visions for a sustainable bioeconomy

The Bioeconomy is both an enabler and an end for the European Green Deal transformation: achieving the EGD transformation entails transforming the very meaning of sustainable bioeconomy. Among the deepest and most effective leverage points to transform a system are the worldviews driving our behaviours: they yield an enormous power to influence the framings which determine the solution space we explore. Transforming the bioeconomy, thus, requires reflecting on the stories we tell about ourselves, our place in nature, and our relationship with others. Scholars have highlighted how narratives surrounding the EU Bioeconomy have predominantly embraced a “Green Growth” perspective, centred around economic growth, technological innovation, and anthropocentric values, largely ignoring the social and justice dimensions, as well as not questioning the role, relations, and responsibilities of humans in the web of life. These dominant framings are increasingly contested, though, because they have failed to produce the social and ecological outcomes desired. This report introduces perspectives which have been under-represented in the Bioeconomy discourse and integrates them into an alternative vision for a “green, just and sufficient bioeconomy”. This vision places environmental sustainability and social equity at its core, regardless of economic growth; has an inclusive and participatory perspective; care, respect, and reciprocity for and with other humans and non-humans are core values; technology is important to deliver on the green and just objectives, but ethical considerations for new technologies are openly debated