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The original version of this Article contained an incorrect reference to the database used in the study (reference no. 73). This has been corrected in both the PDF and HTML versions of the Article.

The original version of this Article contained an incorrect reference to the database used in the study (reference no. 73). This has been corrected in both the PDF and HTML versions of the Article.

This study evaluates the techno-economic feasibility of energy and phosphorus (P) fertilizer (PF) recovery from municipal sewage sludge (MSS) through incineration in new combustion plants. We evaluated the economic impact of five critical process design choices: (1) boiler type, (2) fuel (MSS mono-combustion/co-combustion with wheat straw), (3) production scale (10/100 MW), (4) products (heat, electricity, PF), and (5) ash destination. Aspen Plus modeling provided mass and energy balances of each technology scenario. The economic feasibility was evaluated by calculating the minimum selling price of the products, as well as the MSS gate fees required to reach profitability. The dependency on key boundary conditions (operating time, market prices, policy support) was also evaluated. The results showed a significant dependency on both energy and fertilizer market prices and on financial support in the form of an MSS gate fee. Heat was preferred over combined heat and power (CHP), which was feasible only on the largest scale (100 MW) at maximum annual operating time (8000 h/y). Co-combustion showed lower heat recovery cost (19–30 €/MWh) than mono-combustion (29–66 €/MWh) due to 25–35% lower energy demand and 17–25% higher fuel heating value. Co-combustion also showed promising performance for P recovery, as PF could be recovered without ash post-treatment and sold at a competitive price, and co-combustion could be applicable also in smaller cities. When implementing ash post-treatment, the final cost of ash-based PF was more than four times the price of commercial PF. In conclusion, investment in a new combustion plant for MSS treatment appears conditional to gate fees unless the boundary conditions would change significantly. Validerad;2022;Nivå 2;2022-03-25 (hanlid)

Biorefineries for the production of fuels, chemicals, or materials can be an important contributor to reducing dependence on fossil fuels. The economic performance of the biorefinery supply chain can be increased by, for example, industrial integration to utilise excess heat and products, increasing size to improve economy of scale, and using intermediate upgrading to reduce feedstock transport cost. To enable a large-scale introduction of biorefineries it is important to identify cost efficient supply chain configurations. This work investigates a lignocellulosic biorefinery concept integrated with forest industry, focusing on how different economic conditions affect the preferred supply chain configurations. The technology investigated is black liquor gasification, with and without the addition of pyrolysis liquids to increase production capacity. Primarily, it analyses trade-offs between high biomass conversion efficiency and economy of scale effects, as well as the selection of centralised vs. decentralised supply chain configurations. The results show the economic advantage for biomass efficient configurations, when the biorefinery investment is benefited from an alternative investment credit due to the replacement of current capital-intensive equipment at the host industry. However, the investment credit received heavily influenced the cost of the biorefinery and clearly illustrates the benefit for industrial integration to reduce the cost of biorefineries. There is a benefit for a decentralised supply chain configuration under very high biomass competition. However, for lower biomass competition, site-specific conditions will impact the favourability of either centralised or decentralised supply chain configurations. Validerad;2018;Nivå 2;2018-09-19 (svasva)

Forest-derived biofuels have been on the agenda for several decades. Despite extensive research and development efforts, forest biofuel concepts have nevertheless not yet been realized on any significant scale. The discrepancy between the expectations from the research community and the lack of momentum regarding biofuel production raises the question of if and how research results can be used to achieve such goals. Here, we report results from an interview study with the aim of evaluating how energy system models can be used to illustrate barriers and drivers for forest biofuels, with focus on Swedish conditions, using the BeWhere model as case. The study is framed as an example of expertise, and problematizes how energy system models are interpreted among expected users. While the interviews revealed some general scepticism regarding models, and what kinds of questions they can answer, the belief was also expressed that increased complexity might be an advantage in terms of being able to accommodate more barriers against forest biofuels. The study illustrates the complexity of this policy area, where an energy system model can answer some, but never all, what if...? questions. The results reveal a need for reformation in energy system modelling in order to more explicitly make society the subject of the work, and also illustrate that the belief in expertise as a tool for consensus-building in decision-making should be questioned. Funding Agencies|collaborative research program Renewable Transportation Fuels and Systems (Fornybara Drivmedel och System) [38118-1]; Swedish Energy Agency; Swedish Knowledge Centre for Renewable Transportation Fuels; Bio4Energy

A large number of national and international techno-economic studies on industrially integrated gasifiers for production of biofuels have been published during the recent years. These studies comprise different types of gasifiers (fluidized bed, indirect and entrained flow) integrated in different industries for the production of various types of chemicals and transportation fuels (SNG, FT-products, methanol, DME etc.) The results are often used for techno-economic comparisons between different biorefinery concepts. One relatively common observation is that even if the applied technology and the produced biofuel are the same, the results of the techno-economic studies may differ significantly. The main objective of this project has been to perform a comprehensive review of publications regarding industrially integrated biomass gasifiers for motor fuel production. The purposes have been to identify and highlight the main reasons why similar studies differ considerably and to prepare a basis for “fair” techno-economic comparisons. Another objective has been to identify possible lack of industrial integration studies that may be of interest to carry out in a second phase of the project. Around 40 national and international reports and articles have been analysed and reviewed. The majority of the studies concern gasifiers installed in chemical pulp and paper mills where black liquor gasification is the dominating technology. District heating systems are also well represented. Only a few studies have been found with mechanical pulp and paper mills, steel industries and the oil refineries as case basis. Other industries have rarely, or not at all, been considered for industrial integration studies. Surprisingly, no studies regarding integration of biomass gasification neither in saw mills nor in wood pellet production industry have been found. There are several reasons why the results of the reviewed techno-economic studies vary. Some examples are that different system boundaries have been set and that different technical and economic assumptions have been made, product yields and energy efficiencies may be calculated using different methods etc. For obvious reasons, the studies are not made in the same year, which means that different monetary exchange rates and indices have been applied. It is therefore very difficult, and sometimes even impossible, to compare the technical as well as the economic results from the different studies. When technical evaluations are to be carried out, there is no general method for how to set the system boundaries and no right or wrong way to calculate the system efficiencies as long as the boundaries and methods are transparent and clearly described. This also means that it becomes fruitless to compare efficiencies between different concepts unless the comparison is done on an exactly equal basis. However, even on an equal basis, a comparison is not a straight forward process. For example, calculated efficiencies may be based on the marginal supply, which then become very dependent on how the industries exploit their resources before the integration. The resulting efficiencies are therefore very site-dependent. Increasing the system boundaries to include all in- and outgoing energy carriers from the main industry, as well as the integrated gasification plant (i.e. total plant mass and energy balance), would inflict the same site-dependency problem. The resulting system efficiency is therefore a measure of the potential improvement that a specific industry could achieve by integrating a biomass gasification concept. When estimating the overall system efficiency of industrial biorefinery concepts that include multiple types of product flows and energy sources, the authors of this report encourage the use of electrical equivalents as a measure of the overall system efficiency. This should be done in order to take the energy quality of different energy carriers into concern. In the published economic evaluations, it has been found that there is a large number of studies containing both integration and production cost estimates. However, the number of references for the cost data is rather limited. The majority of these have also been published by the same group of people and use the same or similar background information. The information in these references is based on quotes and estimates, which is good, however none of these are publically available and therefore difficult to value with respect to content and accuracy. It has further been found that the variance in the operational costs is quite significant. Something that is particularly true for biomass costs, which have a high variance. This may be explained by natural variations in the quality of biomass used, but also to the different markets studied and the dates when the studies were performed. It may be seen from the specific investment costs that there is a significant spread in the data. It may also be seen that the differences in capital employed and process yields will result in quite large variations in the production cost of the synthetic fuels. On a general note, the studies performed are considering future plants and in some cases assumes technology development. It is therefore relevant to question the use of today’s prices of utilities and feedstock’s. It is believed that it would be more representative to perform some kind of scenario analysis using different parameters resulting in different cost assumptions to better exemplify possible futures. Due to the surprising lack of reports and articles regarding integration of biomass gasifiers in sawmills, it would be of great interest to carry out such a study. Also larger scale wood pellet production plants could be of interest as a potential gasification based biorefinery.

Godkänd; 2013; 20140327 (eliwet)

Godkänd; 2013; 20130416 (roblund)

With a high availability of lignocellulosic biomass and various types of cellulosic by-products, as well as a large number of industries, Sweden is a country of great interest for future large scale production of sustainable, next generation biofuels. This is most likely also a necessity as Sweden has the ambition to be independent of fossil fuels in the transport sector by the year 2030 and completely fossil free by 2050. In order to reach competitive biofuel production costs, plants with large production capacities are likely to be required. Feedstock intake capacities in the range of about 1-2 million tonnes per year, corresponding to a biomass feed of 300-600 MW, can be expected, which may lead to major logistical challenges. To enable expansion of biofuel production in such large plants, as well as provide for associated distribution requirements, it is clear that substantial infrastructure planning will be needed. The geographical location of the production plant facilities is therefore of crucial importance and must be strategic to minimise the transports of raw material as well as of final product. Competition for the available feedstock, from for example forest industries and CHP plants (combined heat and power) further complicates the localisation problem. Since the potential for an increased biomass utilisation is limited, high overall resource efficiency is of great importance. Integration of biofuel production processes in existing industries or in district heating systems may be beneficial from several aspects, such as opportunities for efficient heat integration, feedstock and equipment integration, as well as access to existing experience and know-how. This report describes the development of BeWhere Sweden, a geographically explicit optimisation model for localisation of next generation biofuel production plants in Sweden. The main objective of developing such a model is to be able to assess production plant locations that are robust to varying boundary conditions, in particular regarding energy market prices, policy instruments, investment costs, feedstock competition and integration possibilities with existing energy systems. This report also presents current and future Swedish biomass resources as well as a compilation of three consistent future energy scenarios. BeWhere is based on Mixed Integer Linear Programming (MILP) and is written in the commercial software GAMS, using CPLEX as a solver. The model minimises the cost of the entire studied system, including costs and revenues for biomass harvest and transportation, production plants, transportation and delivery of biofuels, sales of co-products, and economic policy instruments. The system cost is minimised subject to constraints regarding, for example, biomass supply, biomass demand, import/export of biomass, production plant operation and biofuel demand. The model will thus choose the least costly pathways from one set of feedstock supply points to a specific biofuel production plant and further to a set of biofuel demand points, while meeting the demand for biomass in other sectors. BeWhere has previously been developed by the International Institute for Applied Systems Analysis (IIASA), Laxenburg, Austria and Luleå University of Technology and has been used in several studies on regional and national levels, as well as on the European level. However, none of the previous model versions has included site-specific conditions in existing industries as potential locations for industrially integrated next generation biofuel production. Furthermore, they also usually only consider relatively few different production routes. In this project, bottom-up studies of integrated biofuel production have been introduced into a top-down model and taken to a higher system level, and detailed, site-specific input data of potential locations for integrated biofuel production has been included in the model. This report covers the first stages of model development of BeWhere Sweden. The integration possibilities have been limited to the forest industry and a few district heating networks, and the feedstocks to biomass originating from the forest. The number of biofuel production technologies has also been limited to three gasification-based concepts producing DME, and two hydrolysis- and fermentation-based concepts producing ethanol. None of the concepts considered is yet commercial on the scale envisioned here. Preliminary model runs have been performed, with the main purpose to identify factors with large influence on the results, and to detect areas in need of further development and refinement. Those runs have been made using a future technology perspective but with current energy market conditions and biomass supply and demand. In the next stage of model development different roadmap scenarios will be modelled and analysed. Three different roadmap scenarios that describe consistent assessments of the future development concerning population, transport and motor fuel demands, biomass resources, biomass demand in other industry sectors, energy and biomass market prices etc. have been constructed within this project and are presented in this report. As basis for the scenarios the report “Roadmap 2050” by the Swedish Environmental Protection Agency (EPA) has been used, using 2030 as a target year for the scenarios. Roadmap scenario 1 is composed to resemble “Roadmap 2050” Scenario 1. Roadmap scenario 2 represents an alternative development with more protected forest and less available biomass resources, but a larger amount of biofuels in the transport system, partly due to a higher transport demand compared to Roadmap scenario 1. Finally Roadmap scenario 3 represents a more “business as usual” scenario with more restrictive assumptions compared to the other two scenarios. In total 55 potential biofuel plant sites have been included at this stage of model development. Of this 32 sites are pulp/paper mills, of which 24 have chemical pulp production (kraft process) while eight produce only mechanical pulp and/or paper. Seven of the pulp mills are integrated with a sawmill, and 18 additional stand-alone sawmills are also included, as are five district heating systems. The pulp and paper mills and sawmills are included both as potential biofuel plant sites, as biomass demand sites regarding wood and bioenergy, and as biomass supply sites regarding surplus by-products. District heating systems are considered both regarding bioenergy demand and as potential plant sites. In the preliminary model runs, biofuel production integrated in chemical pulp mills via black liquor gasification (BLG) was heavily favoured. The resulting total number of required production plants and the total biomass feedstock volumes to reach a certain biofuel share target are considerably lower when BLG is considered. District heating systems did not constitute optimal plant locations with the plant positions and heat revenue levels assumed in this study. With higher heat revenues, solid biomass gasification (BMG) with DME production was shown to be potentially interesting. With BLG considered as a production alternative, however, extremely high heat revenues would be needed to make BMG in district heating systems competitive. The model allows for definition of biofuel share targets for Sweden overall, or to be fulfilled in each county. With targets set for Sweden overall, plant locations in the northern parts of Sweden were typically favoured, which resulted in saturation of local biofuel markets and no biofuel use in the southern parts. When biofuels needed to be distributed to all parts of Sweden, the model selected a more even distribution of production plants, with plants also in the southern parts. Due to longer total transport distances and non-optimal integration possibilities, the total resulting system cost was higher when all counties must fulfil the biofuel share target. The total annual cost to fulfil a certain biofuel target would also be considerably higher without BLG in the system, as would the total capital requirement. This however presumes that alternative investments would otherwise be undertaken, such as investments in new recovery boilers. Without alternative investments the difference between a system with BLG and a system without BLG would be less pronounced. In several cases the model located two production plants very close to each other, which would create a high biomass demand on a limited geographic area. The reason is that no restrictions on transport volumes have yet been implemented in the model. Further, existing onsite co-operations between for example sawmills and pulp mills have not always been captured by the input data used for this report, which can cause the consideration of certain locations as two separate plant sites, when in reality they are already integrated. It is also important to point out that some of the mill specific data (obtained from the Swedish Forest Industries Federation’s environmental database) was identified to contain significant errors, which could affect the results related to the plant allocations suggested in this report. Due to the early model development stage and the exclusion of for example many potential production routes and feedstock types, the model results presented in this report must be considered as highly preliminary. A number of areas in need of supplementing have been identified during the work with this report. Examples are addition of more industries and plant sites (e.g. oil refineries), increasing the number of other production technologies and biofuels (e.g. SNG, biogas, methanol and synthetic diesel), inclusion of gas distribution infrastructures, and explicit consideration of import and export of biomass and biofuel. Agricultural residues and energy crops for biogas production are also considered to be a very important and interesting completion to the model. Furthermore, inclusion of intermediate products such as torrefied biomass, pyrolysis oil and lignin extracted from chemical pulp mills would make it possible to include new production chains that are currently of significant interest for technology developers. As indicated above, the quality of some input data also needs to be improved before any definite conclusions regarding next generation biofuel plant localisations can be drawn.Due to the early model development stage and the exclusion of for example many potential production routes and feedstock types, the model results presented in this report must be considered as highly preliminary. A number of areas in need of supplementing have been identified during the work with this report. Examples are addition of more industries and plant sites (e.g. oil refineries), increasing the number of other production technologies and biofuels (e.g. SNG, biogas, methanol and synthetic diesel), inclusion of gas distribution infrastructures, and explicit consideration of import and export of biomass and biofuel. Agricultural residues and energy crops for biogas production are also considered to be a very important and interesting completion to the model. Furthermore, inclusion of intermediate products such as torrefied biomass, pyrolysis oil and lignin extracted from chemical pulp mills would make it possible to include new production chains that are currently of significant interest for technology developers. As indicated above, the quality of some input data also needs to be improved before any definite conclusions regarding next generation biofuel plant localisations can be drawn. A further developed BeWhere Sweden model has the potential for being a valuable tool for simulation and analysis of the Swedish energy system, including the industry and transport sectors. The model can for example be used to analyse different biofuel scenarios and estimate cost effective biofuel production plant locations, required investments and costs to meet a certain biofuel demand. Today, concerned ministries and agencies base their analyses primary on results from the models MARKAL and EMEC, but none of these consider the spatial distribution of feedstock, facilities and energy demands. Sweden is a widespread country with long transport distances, and where logistics and localisation of production plants are crucial for the overall efficiency. BeWhere Sweden considers this and may contribute with valuable input that can be used to complement and validate results from MARKAL and EMEC; thus testing the feasibility of these model results. This can be of value for different biofuel production stakeholders as well as for government and policy makers. Further, Sweden is also of considerable interest for future next generation biofuel production from a European perspective. By introducing a link to existing models that operate on a European level, such as BeWhere Europe and the related IIASA model GLOBIOM, BeWhere Sweden could also be used to provide results of value for EU policies and strategies. Sverige besitter goda tillgångar på skogsbiomassa och olika typer av cellulosabaserat avfall som potentiellt kan användas till framtida storskalig produktion av nästa generations biodrivmedel. Eftersom Sverige har satt som mål att vara oberoende av fossila bränslen inom transportsektorn år 2030 och helt fossilfritt 2050, är detta förmodligen också en nödvändighet. Att nå konkurrenskraftiga produktionskostnader kommer sannolikt kräva stora biodrivmedelsanläggningar. Ett råvaruintag i spannet 1-2 miljoner ton per år (motsvarande en anläggningskapacitet på 300-600 MW), kan förväntas, vilket innebär stora logistiska utmaningar. För att möjliggöra biodrivmedelsproduktion i så stora anläggningar kommer betydande infrastrukturplanering att vara nödvändigt. Den geografiska placeringen av produktionsanläggningar är därför av avgörande betydelse och måste vara strategisk för att minimera transporterna av såväl råvaror som slutprodukter. Konkurrensen om den tillgängliga råvaran från exempelvis skogsindustrin och kraftvärmesektorn, komplicerar lokaliseringsproblemet ytterligare. Eftersom potentialen för ett ökat biomassautnyttjande är begränsad, är resurseffektiviteten av stor betydelse. Integration av drivmedelsproduktion i befintliga industrier eller fjärrvärmesystem kan vara fördelaktigt ur flera perspektiv. Exempel är möjligheter till effektiv värmeintegrering, integrering av råmaterial och utrustning, samt utnyttjande av befintliga kunskaper och erfarenheter. Denna rapport beskriver utvecklingen av BeWhere Sweden – en geografiskt explicit optimeringsmodell för lokalisering av nästa generations biodrivmedelsproduktion i Sverige. Det främsta syftet med modellen är att kunna identifiera och värdera lokaliseringar som är så robusta som möjligt i förhållande till olika randvillkor, i synnerhet gällande energimarknadsaspekter, styrmedel, investeringskostnader och råvarukonkurrens. I rapporten presenteras också en översikt av nuvarande och framtida biobränsleresurser i Sverige, samt en sammanställning av tre konsekventa framtidsscenarier. BeWhere bygger på blandad heltalsprogrammering (Mixed Integer Linear Programming, MILP) och är skriven i den kommersiella programvaran GAMS, med CPLEX som lösare. Modellen minimerar kostnaden för hela det studerade systemet, inklusive kostnader och intäkter för produktion och transport av biomassa, produktionsanläggningar, transport och leverans av biodrivmedel, försäljning av biprodukter och ekonomiska styrmedel. System-kostnaden minimeras under ett antal olika bivillkor som beskriver till exempel tillgång och efterfrågan på biomassa, import/export av biomassa och biodrivmedel, anläggningsdrift och efterfrågan på biodrivmedel. Modellen kommer således välja de minst kostsamma kombinationerna av råvaror, produktionsanläggningar och leveranser av biodrivmedel, samtidigt som efterfrågan på biomassa i andra sektorer tillgodoses. BeWhere-modellen har tidigare utvecklats vid International Institute for Applied Systems Analysis (IIASA) i Laxenburg, Österrike och vid Luleå Tekniska Universitet, och har använts i ett stort antal studier på regional och nationell nivå, liksom på EU-nivå. Ingen av de tidigare modellerna har dock tagit hänsyn till platsspecifika förhållanden för potentiell integration av biodrivmedelsproduktion i exempelvis industrier. Dessutom har tidigare modeller generellt inkluderat relativt få olika produktionsalternativ. I det här projektet har bottom-up-studier av integrerad biodrivmedelsproduktion introducerats i en top-down-modell och tagits till en högre systemnivå, med beaktande av detaljerade platsspecifika data för de potentiella lägena för integrerad biodrivmedelsproduktion. Denna rapport omfattar de första faserna i modellutvecklingen av BeWhere Sweden. Integrationsmöjligheterna har här begränsats till skogsindustri och ett fåtal fjärrvärmenät, och råvarorna till biomassa som härrör från skogen. Produktionsteknikerna har begränsats till tre förgasningsbaserade koncept för produktion av DME, samt två hydrolys-och jäsningsbaserade koncept för produktion av etanol. Ingen av dessa tekniker är ännu kommersiell i den skala som beaktats i detta projekt. Preliminära modellkörningar har genomförts med det huvudsakliga syftet att identifiera faktorer med stor inverkan på resultaten, samt behov av ytterligare modellutveckling och förbättring. Dessa körningar har gjorts utifrån dagens system, med nuvarande energimarknadsvillkor och tillgång och efterfrågan på biomassa, men med ett framtidsperspektiv gällande tekniker. I nästa steg av modellutvecklingen kommer olika framtidscenarier att modelleras och analyseras. Tre olika scenarier med bedömningar av framtida befolkningsutveckling, transport- och drivmedelsbehov, tillgång och efterfrågan på biomassa i olika samhällssektorer, samt marknadspriser på energi och biomassa, har skapats och presenteras i denna rapport. Naturvårdsverkets rapport ”Färdplan 2050” har använts som underlag för scenarierna, men med 2030 som tidsram. Färdplansscenario 1 är sammansatt för att efterlikna Scenario 1 i ”Färdplan 2050”. Färdplansscenario 2 representerar en alternativ utveckling med mer skyddad skog och färre tillgängliga biomassaresurser, men ed en större mängd biodrivmedel i transportsystemet, delvis beroende på en högre efterfrågan på transporter jämfört med i Färdplansscenario 1. Färdplansscenario 3 är slutligen mer av ett ”business as usual”-scenario, med generellt mer restriktiva antaganden jämfört med de andra två scenarierna. Sammanlagt 55 potentiella platser för integrerad biodrivmedelsproduktion har inkluderats i detta skede av modellutvecklingen. Av dessa är 32 massa- och pappersindustrier, varav 24 producerar kemisk massa (sulfatmassa) och åtta tillverkar mekanisk massa och/eller papper. Sju av massabruken är även integrerade med ett sågverk. Ytterligare 18 fristående sågverk är också beaktade, liksom fem fjärrvärmesystem. Massa-och pappersbruken och sågverken ingår i modellen dels som möjliga lokaliseringar för biodrivmedelsproduktion, dels med avseende på biobränslebehov (stamved och/eller energi) som måste tillfredsställas, och dels som producenter av biobränsle (överskott av industriella biprodukter). Fjärrvärmesystemen beaktas både i form av möjliga lägen för integrerad drivmedelsproduktion, och med avseende på behov av bioenergi. I de preliminära modellkörningarna visade sig drivmedelsproduktion integrerat i kemiska massabruk baserat på svartlutsförgasning (BLG) vara särskilt gynnsamt. När BLG beaktades var både det resulterande erforderliga antalet produktionsanläggningar och det totala biobränslebehovet för att uppnå ett visst andelsmål för biodrivmedel i transportsektorn, betydligt lägre än om BLG inte beaktades. Fjärrvärmesystem visade sig generellt inte utgöra optimala lokaliseringar med de system som innefattats och de värmepriser som antagits i denna rapport. Med högre värmeintäkter visade sig att förgasning av fasta biobränslen med DME-produktion kan vara potentiellt intressant. Med BLG-baserad produktion inkluderad som produktionsalternativ skulle dock extremt höga värmepriser behövas för att göra fastbränsleförgasning i fjärrvärmesystem konkurrenskraftigt. I modellen kan mål för andelen biodrivmedel i transportsektorn anges för Sverige som helhet, eller som mål som måste uppfyllas i varje län. När målet angavs övergripande för Sverige gynnades anläggningslokaliseringar i norra Sverige, vilket ledde till mättnad av de lokala biodrivmedelsmarknaderna och ingen biodrivmedelsanvändning i de mer tätt-befolkade södra delarna. Om ett biodrivmedelsmål istället angavs länsvis valde modellen en jämnare geografisk fördelning av produktionsanläggningarna, med anläggningar även i södra Sverige. På grund av längre totala transportavstånd och icke-optimala integrations-möjligheter resulterade detta i en högre total systemkostnad jämfört med när målet angavs för Sverige som helhet. Den totala kostnaden för att uppfylla ett visst biodrivmedelsmål, liksom det totala kapitalbehovet, skulle också vara betydligt högre utan BLG i systemet. Detta förutsätter dock att alternativa investeringar annars skulle ha genomförts, såsom investeringar i nya sodapannor. Utan beaktande av alternativa investeringar skulle skillnaden mellan ett system med BLG och ett system utan BLG, vara mindre. I flera körningar valde modellen två produktionsanläggningar mycket nära varandra, vilket skulle innebära en stor efterfrågan på biomassa på ett begränsat geografiskt område. Anledningen är dels att restriktioner för transportvolymer ännu inte införts i modellen, dels att befintliga samarbeten mellan exempelvis sågverk och massabruk inte alltid fångats av de indata som använts. Detta kan medföra att vissa platser betraktats som två separata anläggningar, när de i verkligheten redan har en hög grad av integrering och därmed borde betraktas som ett läge. Under arbetets gång har en del bruksspecifika data som använts (vilka erhållits från Skogsindustriernas miljödatabas) visat sig innehålla väsentliga felaktigheter. Det är därför viktigt att poängtera att detta kan påverka resultaten gällande de anläggningslokaliseringar som framstår som mest gynnsamma. På grund av modellens tidiga utvecklingsstadium och att ett flertal potentiella produktionsalternativ och råvaror ännu inte inkluderats i modellen, måste de resultat som presenterats i denna rapport betraktas som mycket preliminära. Under arbetet har ett antal områden i behov av komplettering och vidareutveckling identifierats. Exempel är tillägg av både fler industrityper (t.ex. oljeraffinaderier) och fler potentiella anläggningsplatser, utökning av antalet produktionstekniker och drivmedel (t.ex. SNG, biogas, metanol och syntetisk diesel), inkludering av infrastrukturer för gasdistribution, samt explicit hänsyn till import och export av biomassa och biodrivmedel. Restprodukter från jordbruket och energigrödor för biogasproduktion anses också vara ett viktig och intressant tillägg till modellen. Dessutom skulle införandet av intermediärprodukter som torrefierad biomassa, pyrolysolja och lignin från kemiska massabruk göra det möjligt att inkludera ytterligare nya produktionskedjor som för närvarande är av betydande intresse för teknikutvecklare. Som diskuterats ovan behöver kvaliteten på vissa indata också förbättras innan några definitiva slutsatser kan dras om var nästa generations biodrivmedelsproduktion bör vara lokaliserad. En vidareutvecklad BeWhere Sweden-modell har potential att utgöra ett värdefullt verktyg för simulering och analys av det svenska energisystemet, industrin och transportsektorn inkluderade. Modellen kan exempelvis användas för att analysera olika biodrivmedels-scenarier och för att identifiera och utvärdera kostnadseffektiva lokaliseringar för drivmedelsproduktion, nödvändiga investeringar, samt kostnader och biomassabehov för att möta en viss efterfrågan på biodrivmedel. Idag baserar berörda myndigheter primärt sina analyser på resultat från modellerna MARKAL och EMEC. Ingen av dessa modeller tar dock hänsyn till den geografiska fördelningen av råvaror, anläggningar och energi- och råvarubehov. Sverige är ett vidsträckt land med långa transportavstånd där logistik och lokalisering av produktionsanläggningar är avgörande för den totala effektiviteten. BeWhere Sweden beaktar dessa aspekter och kan bidra med värdefulla resultat som kan användas för att i tur komplettera och validera resultat från MARKAL och EMEC, och på så sätt testa implementerbarheten av dessa modellresultat. Detta kan vara av värde för såväl intressenter i biodrivmedelstillverkning, som för myndigheter och politiska beslutsfattare. Vidare är Sverige av stort intresse för framtida tillverkning av nästa generations biodrivmedel även ur ett europeiskt perspektiv. Genom att införa en länk till befintliga modeller som verkar på europeisk nivå, såsom BeWhere Europe och den relaterade IIASA-modellen GLOBIOM, kan BeWhere Sweden också användas för att generera resultat av värde för EU:s politik och strategier.

Godkänd; 2012; 20121114 (roblund)

Bioenergy will play an important role in reaching the EU targets for renewable energy. Sweden, with abundant forest resources and a well-established forest industry, has a key position regarding modern biomass use. Biomass gasification (BMG) offers several advantages compared to biomass combustion-based processes, the most prominent being the possibility for downstream conversion to motor fuels (biofuels), and the potential for higher electrical efficiency if used for electricity generation in a biomass integrated gasification combined cycle (BIGCC). BMG-based processes in general have a considerable surplus of heat, which facilitates integration with district heating or industrial processes. In this thesis integration of large-scale BMG, for biofuel or electricity production, with other parts of the energy system is analysed. Focus is on forest-based biomass, with the analysis including techno-economic aspects as well as considerations regarding effects on global fossil CO2 emissions. The analysis has been done using two approaches – bottom-up with detailed case studies of BMG integrated with local systems, and top-down with BMG studied on a European scale. The results show that BMG-based biofuel or electricity production can constitute economically interesting alternatives for integration with district heating or pulp and paper production. However, due to uncertainties concerning future energy market conditions and due to the large capital commitment of investment in BMG technology, forceful economic support policies will be needed if BMG is a desired route for the future energy system, unless oil and electricity prices are high enough to provide sufficient incentives for BMG-based biofuel or electricity production. While BMG-based biofuel production could make integration with either district heating or pulp and paper production economically attractive, BIGCC shows considerably more promise if integrated with pulp and paper production than with district heating. Bioenergy use is often considered CO2-neutral, because uptake in growing plants is assumed to fully balance the CO2 released when the biomass is combusted. As one of the alternatives in this thesis, biomass is viewed as limited. This means that increased use of bioenergy in one part of the energy system limits the amount of biomass available for other applications, thus increasing the CO2 emissions for those applications. The results show that when such marginal effects of increased biomass use are acknowledged, the CO2 mitigation potential for BMG-based biofuel production becomes highly uncertain. In fact, most of the BMG-based biofuel cases studied in this thesis would lead to an increase rather than the desired decrease of global CO2 emissions, when considering biomass as limited. Bioenergi spelar en viktig roll för att nå EU:s mål för förnybar energi. Sverige har med sina goda skogstillgångar och sin väletablerade skogsindustri en nyckelposition vad gäller modern bioenergianvändning. Förgasning av biomassa har flera fördelar jämfört med förbränningsbaserade processer - i synnerhet möjligheten att konvertera lågvärdiga råvaror till exempelvis fordonsdrivmedel. Används gasen istället för elproduktion kan en högre verkningsgrad nås om gasen används i en kombicykel, jämfört med i en konventionell ångturbincykel. De förgasningsbaserade processerna har i allmänhet ett betydande överskott av värme, vilket möjliggör integrering med fjärrvärmesystem eller industriella processer. I denna avhandling analyseras integrering av storskalig biomassaförgasning för drivmedelseller elproduktion, med andra delar av energisystemet. Skogsbaserad biomassa är i fokus och analysen behandlar såväl teknoekonomiska aspekter, som effekter på globala fossila CO2-utsläpp. Forskningen har gjorts på två olika systemnivåer - dels i form av detaljerade fallstudier av biomassaförgasning integrerat med lokala svenska system, dels i form av systemstudier på europeisk nivå. Resultaten visar att förgasningsbaserad biodrivmedels- eller elproduktion kan komma att utgöra ekonomiskt intressanta alternativ för integrering med fjärrvärme eller massa- och papperstillverkning. På grund av osäkerheter i fråga om framtida energimarknadsförhållanden och på grund av de höga kapitalkostnaderna som investering i förgasningsanläggningar innebär, kommer kraftfulla ekonomiska styrmedel krävas om biomassaförgasning är en önskad utvecklingsväg för framtidens energisystem, såvida inte olje- och elpriserna är höga nog att i sig skapa tillräckliga incitament. Medan förgasningsbaserad drivmedelsproduktion kan vara ekonomiskt attraktivt att integrera med såväl fjärrvärme som med massa- och papperstillverkning, framstår förgasningsbaserad elproduktion som betydligt mer lovande vid integrering med massa- och papperstillverkning. Användning av bioenergi anses ofta vara CO2-neutralt, eftersom upptaget av CO2 i växande biomassa antas balansera den CO2 som frigörs när biomassan förbränns. Som ett av alternativen i denna avhandling ses biomassa som begränsad, vilket innebär att ökad användning av bioenergi i en del av energisystemet begränsar den tillgängliga mängden biomassa för andra användare, vilket leder till ökade CO2-utsläpp för dessa. Resultaten visar att när hänsyn tas till denna typ av marginella effekter av ökad biomassaanvändning, blir potentialen för minskade globala CO2-utsläpp med hjälp av förgasningsbaserade tillämpningar mycket osäker. I själva verket skulle de flesta av de förgasningsbaserade drivmedel som studerats i denna avhandling leda till en utsläppsökning, snarare än den önskade minskningen.

Second generation biofuels use non-food lignocellulosic feedstock, for example waste or forest residues, and have in general lower environmental impact than first generation biofuels. In order to reach the 2020 target of 10% renewable energy in transport it will likely be necessary to have a share of at least 3% second generation fuels in the EU fuel mix. However, second generation biofuel production plants will typically need to be very large which puts significant demand on the supply chain. This makes it necessary to carefully choose the geographic location of the production plants. A geographic explicit model for determining the optimal location of biofuel production has been developed at IIASA and has previously been used in studies on national scale. The model is based on mixed integer linear programming and minimizes the total cost of the supply chain, taking into account supply as well as demand side. The aim of this study is to develop the localization model to cover the European Union, and to use it to analyze how for example policy instruments and energy prices affect second generation biofuel production. Two policy instruments are considered; targeted biofuel support and a CO2 cost. Two feedstock types (forest residues and lignocellulosic waste) and three biofuel production technologies (methanol, Fischer-Tropsch diesel (FTD) and lignocellulosic ethanol) are included. For all three technologies heat for district heating is co-produced, and for FTD and ethanol electricity is also co-produced. The results show that with current energy prices and a targeted biofuel support equivalent to existing tax exemptions, over 1.5% of the total transport fuel demand can be met by second generation biofuels to a cost of 18 €/GJ. A CO2 cost of 100 €/tCO2results in a biofuel production equivalent to 2% of the total fuel demand, but to a higher cost (23 €/GJ). Targeted biofuel support promotes FTD which has higher biofuel efficiency, while a CO2 cost shifts the production towards ethanol due to larger co-production of electricity and high CO2 emissions from displaced electricity. In order to reach a 3% second generation fuel share to a reasonable cost waste feedstock must be used. If only forest residues are considered the biofuel supply cost exceeds 30 €/GJ, compared to around 11 €/GJ if low cost waste can also be used. The CO2 reduction potential is found to be strongly connected to the co-products, in particular electricity, with a high biofuel share not being a guarantee for a large decrease of CO2 emissions. It is concluded that in order to avoid suboptimal overall energy systems, heat and electricity applications should also be included when evaluating optimal bioenergy use. It is also concluded that while forceful policies promoting biofuels may lead to a high share of second generation biofuels to reasonable costs, this is not a certain path towards maximized reduction of CO2 emissions. Policies aiming at promoting the use of bioenergy thus need to be carefully designed in order to avoid conflicts between different parts of the EU targets for renewable energy and CO2 emission mitigation.

Currently biofuels have strong political support, both in the EU and Sweden. The EU has, for example, set a target for the use of renewable fuels in the transportation sector stating that all EU member states should use 10% renewable fuels for transport by 2020. Fulfilling this ambition will lead to an enormous market for biofuels during the coming decade. To avoid increasing production of biofuels based on agriculture crops that require considerable use of arable area, focus is now to move towards more advanced second generation (2G) biofuels that can be produced from biomass feedstocks associated with a more efficient land use. Climate benefits and greenhouse gas (GHG) balances are aspects often discussed in conjunction with sustainability and biofuels. The total GHG emissions associated with production and usage of biofuels depend on the entire fuel production chain, mainly the agriculture or forestry feedstock systems and the manufacturing process. To compare different biofuel production pathways it is essential to conduct an environmental assessment using the well-to-tank (WTT) analysis methodology. In Sweden the conditions for biomass production are favourable and we have promising second generation biofuels technologies that are currently in the demonstration phase. In this study we have chosen to focus on cellulose based ethanol, methane from gasification of solid wood as well as DME from gasification of black liquor, with the purpose of identifying research and development potentials that may result in improvements in the WTT emission values. The main objective of this study is thus to identify research and development challenges for Swedish biofuel actors based on literature studies as well as discussions with the the researchers themselves. We have also discussed improvement potentials for the agriculture and forestry part of the WTT chain. The aim of this study is to, in the context of WTT analyses, (i) increase knowledge about the complexity of biofuel production, (ii) identify and discuss improvement potentials, regarding energy efficiency and GHG emissions, for three biofuel production cases, as well as (iii) identify and discuss improvement potentials regarding biomass supply, including agriculture/forestry. The scope of the study is limited to discussing the technologies, system aspects and climate impacts associated with the production stage. Aspects such as the influence on biodiversity and other environmental and social parameters fall beyond the scope of this study. We find that improvement potentials for emissions reductions within the agriculture/forestry part of the WTT chain include changing the use of diesel to low-CO2-emitting fuels, changing to more fuel-efficient tractors, more efficient cultivation and manufacture of fertilizers (commercial nitrogen fertilizer can be produced in plants which have nitrous oxide gas cleaning) as well as improved fertilization strategies (more precise nitrogen application during the cropping season). Furthermore, the cultivation of annual feedstock crops could be avoided on land rich in carbon, such as peat soils and new agriculture systems could be introduced that lower the demand for ploughing and harrowing. Other options for improving the WTT emission values includes introducing new types of crops, such as wheat with higher content of starch or willow with a higher content of cellulose. From the case study on lignocellulosic ethanol we find that 2G ethanol, with co-production of biogas, electricity, heat and/or wood pellet, has a promising role to play in the development of sustainable biofuel production systems. Depending on available raw materials, heat sinks, demand for biogas as vehicle fuel and existing 1G ethanol plants suitable for integration, 2G ethanol production systems may be designed differently to optimize the economic conditions and maximize profitability. However, the complexity connected to the development of the most optimal production systems require improved knowledge and involvement of several actors from different competence areas, such as chemical and biochemical engineering, process design and integration and energy and environmental systems analysis, which may be a potential barrier. Three important results from the lignocellulosic ethanol study are: (i) the production systems could be far more complex and intelligently designed than previous studies show, (ii) the potential improvements consist of a large number of combinations of process integration options wich partly depends on specific local conditions, (iii) the environmental performance of individual systems may vary significantly due to systems design and local conditons. From the case study on gasification of solid biomass for the production of biomethane we find that one of the main advantages of this technology is its high efficiency in respect to converting biomass into fuels for transport. For future research we see a need for improvements within the gas up-grading section, including gas cleaning and gas conditioning, to obtain a more efficient process. A major challenge is to remove the tar before the methanation reaction. Three important results from the biomethane study are: (i) it is important not to crack the methane already produced in the syngas, which indicates a need for improved catalysts for selective tar cracking, (ii) there is a need for new gas separation techniques to facilitate the use of air oxidation agent instead of oxygen in the gasifier, and (iii) there is a need for testing the integrated process under realistic conditions, both at atmospheric and pressurized conditions. From the case study on black liquor gasification for the production of DME we find that the process has many advantages compared to other biofuel production options, such as the fact that black liquor is already partially processed and exists in a pumpable, liquid form, and that the process is pressurised and tightly integrated with the pulp mill, which enhances fuel production efficiency. However, to achieve commercial status, some challenges still remain, such as demonstrating that materials and plant equipment meet the high availability required when scaling up to industrial size in the pulp mill, and also proving that the plant can operate according to calculated heat and material balances. Three important results from the DME study are: (i) that modern chemical pulp mills, having a potential surplus of energy, could become important suppliers of renewable fuels for transport, (ii) there is a need to demonstrate that renewable DME/methanol will be proven to function in large scale, and (iii) there is still potential for technology improvements and enhanced energy integration. Although quantitative improvement potentials are given in the three biofuel production cases, it is not obvious how these potentials would affect WTT values, since the biofuel production processes are complex and changing one parameter impacts other parameters. The improvement potentials are therefore discussed qualitatively. From the entire study we have come to agree on the following common conclusions: (i) research and development in Sweden within the three studied 2G biofuel production technologies is extensive, (ii) in general, the processes, within the three cases, work well at pilot and demonstration scale and are now in a phase to be proven in large scale, (iii) there is still room for improvement although some processes have been known for decades, (iv) the biofuel production processes are complex and site specific and process improvements need to be seen and judged from a broad systems perspective (both within the production plant as well as in the entire well-to-tank perspective), and (v) the three studied biofuel production systems are complementary technologies. Futher, the process of conducting this study is worth mentioning as a result itself, i.e. that many different actors within the field have proven their ability and willingness to contribute to a common report, and that the cooperation climate was very positive and bodes well for possible future collaboration within the framework of the f3 center. Finally, judging from the political ambitions it is clear that the demand for renewable fuels will significantly increase during the coming decade. This will most likely result in opportunities for a range of biofuel options. The studied biofuel options all represent 2G biofuels and they can all be part of the solution to meet the increased renewable fuel demand.

Biomass gasification is considered a key technology in reaching targets for renewable energy and CO2 emissions reduction. This study evaluates policy instruments affecting the profitability of biomass gasification applications integrated in a Swedish district heating (DH) system for the medium-term future (around year 2025). Two gasification applications are included: co-production of SNG (synthetic natural gas) for use as transportation fuel and DH heat in a biorefinery, and BIGCC CHP (biomass integrated gasification combined cycle, combined heat and power). Using an optimisation model the level of policy support necessary to make biofuel production competitive to electricity generation, and the level of tradable green electricity certificates necessary to make gasification based electricity generation competitive to conventional steam cycle technology, are identified. The results show that in order for investment in SNG production to be competitive to investment in electricity production in the DH system, support policies promoting biofuels in the range of 16-22 EUR/MWh are needed. For investment in BIGCC CHP to be competitive to investment in conventional steam cycle CHP tradable green electricity certificates in the range of 4-15 EUR/MWh are necessary. The necessary policy support levels are very sensitive to variations in investment costs. It is concluded that the large capital commitment and strong dependency on policy tools makes it necessary that DH suppliers believe in the long-sightedness of future policy tools, in order for investments in large-scale biomass gasification in DH systems to be realised.