78 research outputs found
Prospects of distributed electricity generation and services based on small scale biomass systems in Ghana
Access to energy is crucial to human welfare; no residential, commercial or industrial activity can be conceived without energy supply. At the same time, current dependence on fossil fuels and their negative effects on global climate claim for urgent alternatives. The situation in Sub-Saharan Africa is poignant: over half of the population, mainly in rural areas, live without access to electricity services. Crop residues from farming communities in those areas are unused; while technology for electricity production from agricultural biomass is progressing, managing decentralised rural electricity projects is still a challenge, especially in developing countries like Ghana, given the variety and complexity of the factors conditioning biomass to energy supply chains. Such complexity has been previously formulated in academic exercises, but with limited practical applicability for energy planners, practitioners and investors.
This research has deployed a holistic approach to biomass-to-energy planning, yet flexible to adapt to different regulatory scenarios and energy supply configurations. A qualitative framework has been developed, taking into consideration four critical components: social development, organisational/institutional, technical, and financial, with their respective metrics. Then, the framework has been applied to three real case study configurations in Ghana, involving primary data collection, sustainability modelling and discussion of the techno-economic feasibility results with policy makers and practitioners.
The first configuration consists in decentralised power generation using crop residues from clustered smallholder farms in 14 districts in Ghana; the number of clustered farms, reference residue yields, and residue densities are determined to assess the distances within which it would be feasible to supply feedstock to biomass power plants. The findings show that a minimum of 22 to 54 larger (10 ha) farms would need to be clustered to enable an economically viable biomass supply to a 1000 kWe plant. Financial analyses indicate that such investment would not be viable under the current renewable feed-in-tariff rates in Ghana; increased tariff by 25% or subsidies from a minimum 30% of investment cost are needed to ensure viability using internal rate of return as an indicator. Carbon finance options are also discussed.
The second configuration focuses on co- and tri-generation from clustered crop residues. Techno-economic results show that 600 kW and 1 MW biomass fuelled plants to generate power, heating (for cassava or maize drying) and cooling (to refrigerate tomatoes) are feasible, considering a minimum 20% yearly profit for investors’ equity. Additional income between 29 and 64 US $/tonne of crop residue would be possible for farmers if a minimum of 60% of the heat produced can be traded. The consideration of carbon financing under the most common traded prices has little impact on the project results; if more favourable schemes (like the Swedish carbon tax) are considered, the viability of co- and tri-generation plants run on agro residue can be possible even with a low level of residual heat sales.
The third configuration analyses minigrid electricity generation and services based on biomass gasification in five Ghanaian communities. Results show that the projected electricity demand compares favourably with the potential supply from available crop residues. Project financing via 100% private funding would not be viable under current national uniform tariffs; however, by applying an end-user tariff equal to the current expenditure on electricity-equivalent uses in the communities, a subsidy of about 35% on initial investment would enable a private entrepreneur an internal rate of return of 15%, whereas a 60% subsidy could enable internal rate of return of 25%.
The outcomes of this research have triggered the interest of Ghanaian and international policy makers, developers and private investors.L'accés a l'energia és crucial per al benestar humà, no es pot concebre cap activitat residencial, comercial o industrial sense subministrament d'energia. Alhora, la dependència actual dels combustibles fòssils i els seus efectes negatius sobre el clima global reclamen alternatives urgents. La situació a l'Àfrica Subsahariana és punyent: més de la meitat de la població, principalment rural, viu sense accés a serveis elèctrics. Tanmateix, en aquestes zones abunden les restes agrícoles. Tot i que la tecnologia per a la producció d'electricitat a partir de biomassa agrícola avança, la promoció de l’electrificació rural descentralitzada continua sent un repte, especialment en països en desenvolupament com Ghana, atesa la varietat i la complexitat de factors que condicionen l’aprofitament energètic de la biomassa. Aquesta complexitat s'ha tractat en exercicis acadèmics, però amb poca aplicabilitat pràctica per a planificadors d'energia, promotors i inversors. A fi de contribuir a una millor planificació i presa de decisions, aquesta Tesi desplega un marc integral d’anàlisi tenint en compte quatre components (desenvolupament social, organitzatiu/institucional, tècnic, i financer), flexible per adaptar-se a diferents configuracions de subministrament d'energia i escenaris reguladors. Aquest marc s'ha aplicat a tres casos reals a Ghana, recollint dades de camp, modelitzant la viabilitat tecno-econòmica i debatent els resultats amb promotors públics i privats. La primera configuració consisteix en la generació elèctrica a partir de restes agrícoles de petites plantacions rurals, en 14 districtes a Ghana, on s?ha determinat la biomassa disponible i la seva localització per calcular les distàncies màximes que permetrien la rendibilitat de petites centrals elèctriques. Els resultats indiquen que un mínim de 22 a 54 plantacions (de 10 ha. cadascuna) haurien d'agrupar-se per permetre un subministrament de biomassa econòmicament viable a una planta de 1000 kWe. Financerament aquesta inversió no seria viable amb les tarifes actuals d’injecció a xarxa; un increment d’aquesta tarifa en un 25%, o bé una subvenció mínima del 30% del cost d'inversió són necessàries per garantir la viabilitat. La segona configuració se centra en la co- i la tri-generació a partir de restes agrícoles. Els resultats de l’anàlisi tècnic-econòmica mostren que centrals de 600 kW i 1 MW per autogenerar electricitat, calor (per assecar mandioca o de blat de moro) i fred (per refrigerar tomàquets) són factibles, fins i tot aportant un retorn anual mínim del 20% per a inversors externs. A més de l’electricitat, en cas de poder vendre com a mínim un 60% de la calor produïda, es podria pagar entre 29 i 64 USD per tona de biomassa. La consideració de bons de carboni a preus habituals de mercat internacional té poc impacte en els resultats del projecte; si es consideren esquemes més favorables (com els bons de carboni a Suècia), la viabilitat de les plantes de co-i tri-generació a partir de restes agrícoles seria possible fins i tot amb un baix nivell de vendes de calor residual. La tercera configuració tracta el servei elèctric amb microxarxes basades en la gasificació de restes agrícoles de comunitats rurals. Els resultats de l’anàlisi en 5 comunitats mostren que el potencial de generació elèctrica a partir de la biomassa disponible supera la demanda elèctrica projectada. El finançament només a partir d’aportacions privades no seria viable amb les tarifes nacionals de consum elèctric actuals; en canvi, si s’aplica una tarifa de consum igual a la despesa actual en usos equivalents a l’electricitat (p.ex. llanternes i piles, bateries de cotxe), una subvenció del 35% sobre la inversió inicial permetria una taxa interna de retorn del 15% a inversors privats, mentre que un 60% la subvenció permetria una taxa interna de retorn del 25%.Els resultats d'aquesta investigació han estat considerats pels grups d'interès de Ghana dins de la formulació de polítiques i regulacions d'electrificació rural, i perspectives de trigeneració i els minigresos de biomassa també han desencadenat l'interès dels inversors privats internacionals i ghanesosPostprint (published version
Prospects of distributed electricity generation and services based on small scale biomass systems in Ghana
Access to energy is crucial to human welfare; no residential, commercial or industrial activity can be conceived without energy supply. At the same time, current dependence on fossil fuels and their negative effects on global climate claim for urgent alternatives. The situation in Sub-Saharan Africa is poignant: over half of the population, mainly in rural areas, live without access to electricity services. Crop residues from farming communities in those areas are unused; while technology for electricity production from agricultural biomass is progressing, managing decentralised rural electricity projects is still a challenge, especially in developing countries like Ghana, given the variety and complexity of the factors conditioning biomass to energy supply chains. Such complexity has been previously formulated in academic exercises, but with limited practical applicability for energy planners, practitioners and investors.
This research has deployed a holistic approach to biomass-to-energy planning, yet flexible to adapt to different regulatory scenarios and energy supply configurations. A qualitative framework has been developed, taking into consideration four critical components: social development, organisational/institutional, technical, and financial, with their respective metrics. Then, the framework has been applied to three real case study configurations in Ghana, involving primary data collection, sustainability modelling and discussion of the techno-economic feasibility results with policy makers and practitioners.
The first configuration consists in decentralised power generation using crop residues from clustered smallholder farms in 14 districts in Ghana; the number of clustered farms, reference residue yields, and residue densities are determined to assess the distances within which it would be feasible to supply feedstock to biomass power plants. The findings show that a minimum of 22 to 54 larger (10 ha) farms would need to be clustered to enable an economically viable biomass supply to a 1000 kWe plant. Financial analyses indicate that such investment would not be viable under the current renewable feed-in-tariff rates in Ghana; increased tariff by 25% or subsidies from a minimum 30% of investment cost are needed to ensure viability using internal rate of return as an indicator. Carbon finance options are also discussed.
The second configuration focuses on co- and tri-generation from clustered crop residues. Techno-economic results show that 600 kW and 1 MW biomass fuelled plants to generate power, heating (for cassava or maize drying) and cooling (to refrigerate tomatoes) are feasible, considering a minimum 20% yearly profit for investors’ equity. Additional income between 29 and 64 US $/tonne of crop residue would be possible for farmers if a minimum of 60% of the heat produced can be traded. The consideration of carbon financing under the most common traded prices has little impact on the project results; if more favourable schemes (like the Swedish carbon tax) are considered, the viability of co- and tri-generation plants run on agro residue can be possible even with a low level of residual heat sales.
The third configuration analyses minigrid electricity generation and services based on biomass gasification in five Ghanaian communities. Results show that the projected electricity demand compares favourably with the potential supply from available crop residues. Project financing via 100% private funding would not be viable under current national uniform tariffs; however, by applying an end-user tariff equal to the current expenditure on electricity-equivalent uses in the communities, a subsidy of about 35% on initial investment would enable a private entrepreneur an internal rate of return of 15%, whereas a 60% subsidy could enable internal rate of return of 25%.
The outcomes of this research have triggered the interest of Ghanaian and international policy makers, developers and private investors.L'accés a l'energia és crucial per al benestar humà, no es pot concebre cap activitat residencial, comercial o industrial sense subministrament d'energia. Alhora, la dependència actual dels combustibles fòssils i els seus efectes negatius sobre el clima global reclamen alternatives urgents. La situació a l'Àfrica Subsahariana és punyent: més de la meitat de la població, principalment rural, viu sense accés a serveis elèctrics. Tanmateix, en aquestes zones abunden les restes agrícoles. Tot i que la tecnologia per a la producció d'electricitat a partir de biomassa agrícola avança, la promoció de l’electrificació rural descentralitzada continua sent un repte, especialment en països en desenvolupament com Ghana, atesa la varietat i la complexitat de factors que condicionen l’aprofitament energètic de la biomassa. Aquesta complexitat s'ha tractat en exercicis acadèmics, però amb poca aplicabilitat pràctica per a planificadors d'energia, promotors i inversors. A fi de contribuir a una millor planificació i presa de decisions, aquesta Tesi desplega un marc integral d’anàlisi tenint en compte quatre components (desenvolupament social, organitzatiu/institucional, tècnic, i financer), flexible per adaptar-se a diferents configuracions de subministrament d'energia i escenaris reguladors. Aquest marc s'ha aplicat a tres casos reals a Ghana, recollint dades de camp, modelitzant la viabilitat tecno-econòmica i debatent els resultats amb promotors públics i privats. La primera configuració consisteix en la generació elèctrica a partir de restes agrícoles de petites plantacions rurals, en 14 districtes a Ghana, on s?ha determinat la biomassa disponible i la seva localització per calcular les distàncies màximes que permetrien la rendibilitat de petites centrals elèctriques. Els resultats indiquen que un mínim de 22 a 54 plantacions (de 10 ha. cadascuna) haurien d'agrupar-se per permetre un subministrament de biomassa econòmicament viable a una planta de 1000 kWe. Financerament aquesta inversió no seria viable amb les tarifes actuals d’injecció a xarxa; un increment d’aquesta tarifa en un 25%, o bé una subvenció mínima del 30% del cost d'inversió són necessàries per garantir la viabilitat. La segona configuració se centra en la co- i la tri-generació a partir de restes agrícoles. Els resultats de l’anàlisi tècnic-econòmica mostren que centrals de 600 kW i 1 MW per autogenerar electricitat, calor (per assecar mandioca o de blat de moro) i fred (per refrigerar tomàquets) són factibles, fins i tot aportant un retorn anual mínim del 20% per a inversors externs. A més de l’electricitat, en cas de poder vendre com a mínim un 60% de la calor produïda, es podria pagar entre 29 i 64 USD per tona de biomassa. La consideració de bons de carboni a preus habituals de mercat internacional té poc impacte en els resultats del projecte; si es consideren esquemes més favorables (com els bons de carboni a Suècia), la viabilitat de les plantes de co-i tri-generació a partir de restes agrícoles seria possible fins i tot amb un baix nivell de vendes de calor residual. La tercera configuració tracta el servei elèctric amb microxarxes basades en la gasificació de restes agrícoles de comunitats rurals. Els resultats de l’anàlisi en 5 comunitats mostren que el potencial de generació elèctrica a partir de la biomassa disponible supera la demanda elèctrica projectada. El finançament només a partir d’aportacions privades no seria viable amb les tarifes nacionals de consum elèctric actuals; en canvi, si s’aplica una tarifa de consum igual a la despesa actual en usos equivalents a l’electricitat (p.ex. llanternes i piles, bateries de cotxe), una subvenció del 35% sobre la inversió inicial permetria una taxa interna de retorn del 15% a inversors privats, mentre que un 60% la subvenció permetria una taxa interna de retorn del 25%.Els resultats d'aquesta investigació han estat considerats pels grups d'interès de Ghana dins de la formulació de polítiques i regulacions d'electrificació rural, i perspectives de trigeneració i els minigresos de biomassa també han desencadenat l'interès dels inversors privats internacionals i ghaneso
Mini-grid electricity service based on local agricultural residues: Feasibility study in rural Ghana
Peer ReviewedPostprint (author's final draft
Financing future-proof local bioenergy: lessons learnt from mentoring of SME pilot projects. WP5 Final report
This deliverable D5.3 is the final report of the activities within WP5 led by UPC, from September 2016 to July 2018.The European bioenergy sector requires a wide promotion for strong investments in regional sustainable supply chain solutions. SMEs are central in the value chain in local bioenergy markets, as they are operating throughout all the stages of bioenergy mobilisation, from forestry management to energy plants or even energy commercialisation to final consumers. One of the major barriers that SMEs face when assessing potential bioenergy operations is the difficulty to access adequate financing; WP5 within project SECURECHAIN aims to analyse such difficulties and contribute to overcome them. The specific objectives of WP5 are:
• O5.1 Carry out targeted market feasibility surveys, pre-checks and develop a risk assessment tool to support the implementation of priority SSCM pilot projects
• O5.2 Mentor companies’ capital call strategies tailored to investor types and upgrade corporate finance disclosing in accordance with International Financial Reporting Standards (IFRS)
• O5.3 Foster lobbying actions and dialogue between financial players and bioenergy market actors to promote the portfolio of investment proposals
This deliverable D5.3 is the final report of the activities within WP5, mainly about period 2 from September 2016 to July 2018. The market pre-check (T5.1) was carried out in phase 1 and reported in deliverable D5.1. The risk assessment analysis (T5.2) performed, the continuous financial mentoring (T5.3) being worked out with the SME business projects, and the roadshows (T5.4) that have been attended, as well as planning activities that were performed during the final year of the project, are documented in this report.Preprin
A MALDI-TOF-based method for studying the transport of BBB shuttles-enhancing sensitivity and versatility of cell-based in vitro transport models.
In recent decades, peptide blood-brain barrier shuttles have emerged as a promising solution for brain drugs that are not able to enter this organ. The research and development of these compounds involve the use of in vitro cell-based models of the BBB. Nevertheless, peptide transport quantification implies the use of large amounts of peptide (upper micromolar range for RP-HPLC-PDA) or of derivatives (e.g. fluorophore or quantum-dot attachment, radiolabeling) in the donor compartment in order to enhance the detection of these molecules in the acceptor well, although their structure is highly modified. Therefore, these methodologies either hamper the use of low peptide concentrations, thus hindering mechanistic studies, or do not allow the use of the unmodified peptide. Here we successfully applied a MALDI-TOF MS methodology for transport quantification in an in vitro BBB cell-based model. A light version of the acetylated peptide was evaluated, and the transport was subsequently quantified using a heavy internal standard (isotopically acetylated). We propose that this MALDI-TOF MS approach could also be applied to study the transport across other biological barriers using the appropriate in vitro transport models (e.g. Caco-2, PAMPA)
Immunosilencing peptides by stereochemical inversion and sequence reversal: retro-D-peptides
Peptides are experiencing a new era in medical research, finding applications ranging from therapeutics to vaccines. In spite of the promising properties of peptide pharmaceuticals, their development continues to be hindered by three weaknesses intrinsic to their structure, namely protease sensitivity, clearance through the kidneys, and immune system activation. Here we report on two retro-D-peptides (H2N-hrpyiah-CONH2 and H2N-pwvpswmpprht-CONH2), which are protease-resistant and retain the original BBB shuttle activity of the parent peptide but are much less immunogenic than the parent peptide. Hence, we envisage that retro-D-peptides, which display a similar topological arrangement as their parent peptides, will expand drug design and help to overcome factors that lead to the failure of peptide pharmaceuticals in pre- and clinical trials. Furthermore, we reveal requirements to avoid or elicit specific humoral responses to therapeutic peptides, which might have a strong impact in both vaccine design and peptide therapeutic agents
Global engineers: key professionals for sustainable human development
Postprint (published version
Improving energy access in rural sub-Saharan Africa
XVII Convocatòria d’ajuts a accions de cooperació - 2009
GRECDH – UPC. Improving Energy Access In Rural sub- Saharan Africa. O-006/09. InformePreprin
HAI Peptide and Backbone Analogs-Validation and Enhancement of Biostability and Bioactivity of BBB Shuttles
Low effectiveness and resistance to treatments are commonplace in disorders of the central nervous system (CNS). These issues concern mainly the blood-brain barrier (BBB), which preserves homeostasis in the brain and protects this organ from toxic molecules and biohazards by regulating transport through it. BBB shuttles-short peptides able to cross the BBB-are being developed to help therapeutics to cross this barrier. BBB shuttles can be discovered by massive exploration of chemical diversity (e.g. computational means, phage display) or rational design (e.g. derivatives from a known peptide/protein able to cross). Here we present the selection of a peptide shuttle (HAI) from several candidates and the subsequent in-depth in vitro and in vivo study of this molecule. In order to explore the chemical diversity of HAI and enhance its biostability, and thereby its bioactivity, we explored two new protease-resistant versions of HAI (i.e. the retro-D-version, and a version that was N-methylated at the most sensitive sites to enzymatic cleavage). Our results show that, while both versions of HAI are resistant to proteases, the retro-D-approach preserved better transport properties
The development of a resource-efficient photovoltaic system
This paper presents the measures taken in the demonstration of the photovoltaic case study developed within the European project ‘Towards zero waste in industrial networks’ (Zerowin), integrating the D4R (Design for recycling, repair, refurbishment and reuse) criteria at both system and industrial network level. The demonstration is divided into three phases. The first phase concerns the development of a D4R photovoltaic concept, the second phase focused on the development of a specific component of photovoltaic systems and the third phase was the demonstration of the D4R design in two complete photovoltaic systems (grid-connected and stand-alone). This paper includes a description of the installed photovoltaic systems, including a brief summary at component level of the lithium ion battery system and the D4R power conditioning system developed for the pilot installations. Additionally, industrial symbioses within the network associated with the photovoltaic systems and the production model for the network are described
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