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‣ Experimental aspects of biomass fuels in a bubbling fluidized bed combustor

dos Santos, Francisco Jose; Goldstein, Leonardo
Fonte: Elsevier B.V. Sa Publicador: Elsevier B.V. Sa
Tipo: Artigo de Revista Científica Formato: 1541-1549
Português
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This work presents experimental information relevant to the combustion of biomass in a bubbling fluidized bed. The biomass distribution in a fluidized bed was studied through tests performed in a cold bed, while the volatiles released in the biomass pyrolysis, the burning rate of the resulting charcoal, and the combustion control regime, were studied through tests performed in a high temperature bed.Visual examination of photographs taken from a transparent walls bed, with a rectangular cross-section, showed that the large fuel particles, typical of biomass processing, were distributed in the bubbles, in the splash zone, and in the emulsion phase. The occurrence of biomass in the emulsion phase was favored by burning biomass particles of greater density and smaller size-expetimentally determined in each case. Decreasing the fuel particle size improved the biomass distribution inside the bed. The same was accomplished by increasing the superficial gas velocity as high as possible, compatibly with the acceptable elutriation.Burning tests showed that the biomass fuels have the advantage of reaching the diffusional regime at temperatures that can be lower than 1000 K, which ensures that the biomass fuels burn in a stable regime. (C) 2007 Elsevier B.V. All rights reserved.

‣ Emission factors from residential combustion appliances burning Portuguese biomass fuels

Fernandes, Ana Patrícia; Alves, Célia; Gonçalves, Cátia; Tarelho, Luís; Pio, Casimiro; Schimdl, C.; Bauer, H.
Fonte: The Royal Society of Chemistry Publicador: The Royal Society of Chemistry
Tipo: Artigo de Revista Científica
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Smoke from residential wood burning has been identified as a major contributor to air pollution, motivating detailed emission measurements under controlled conditions. A series of experiments were performed to compare the emission levels from two types of wood-stoves to those of fireplaces. Eight types of biomass were burned in the laboratory: wood from seven species of trees grown in the Portuguese forest (Pinus pinaster, Eucalyptus globulus, Quercus suber, Acacia longifolia, Quercus faginea, Olea europaea and Quercus ilex rotundifolia) and briquettes produced from forest biomass waste. Average emission factors were in the ranges 27.5–99.2 g CO kg 1, 552–1660 g CO2 kg 1, 0.66– 1.34 g NO kg 1, and 0.82–4.94 g hydrocarbons kg 1 of biomass burned (dry basis). Average particle emission factors varied between 1.12 and 20.06 g kg 1 biomass burned (dry basis), with higher burn rates producing significantly less particle mass per kg wood burned than the low burn rates. Particle mass emission factors from wood-stoves were lower than those from the fireplace. The average emission factors for organic and elemental carbon were in the intervals 0.24–10.1 and 0.18–0.68 g kg 1 biomass burned (dry basis), respectively. The elemental carbon content of particles emitted from the energyefficient ‘‘chimney type’’ logwood stove was substantially higher than in the conventional cast iron stove and fireplace...

‣ Biomass Fuels in SOFC

Cabrita, Isabel
Fonte: Laboratório Nacional de Energia e Geologia Publicador: Laboratório Nacional de Energia e Geologia
Tipo: Conferência ou Objeto de Conferência
Publicado em /03/2013 Português
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Resulting from growing concerns on climate change and resources depletion, biomass has gained increased importance. Security of supply, better environment and economic development, as worldwide goals, are usually drivers for economic growth. Technology developments have adequately not responded to challenges to diversify resources to substitute carbon-intensive fossil fuels at competitive prices. State-of-the-art energy technologies, although advanced, are facing constraints, justifying icreasing effosts in demonstrating efficient and more environmentally friendly tecnhologies.

‣ Biomass quality in a thermoelectric plant along one year

Silva, D.; Tarelho, L.; Silva, J. Figueiredo; Freire, M.; Lopes, M. Helena
Fonte: Laboratório Nacional de Energia e Geologia Publicador: Laboratório Nacional de Energia e Geologia
Tipo: Conferência ou Objeto de Conferência
Publicado em //2013 Português
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ABSTRACT: The biomass quality is an important issue for the operation of a thermoelectric plant. Independently of the combustion technology, the biomass fuels and its characteristics are responsible for some operating problems during the thermochemical conversion of the biomass in thermal energy. These operation problems are related to the boiler and heat exchangers, dedusting technologies (e.g., electrostatic precipitator). Some studies show the phenomena of corrosion and incrustation on the walls of the boiler (named as fouling phenomenon) and on the walls of superheater, economizer, and equipments for flue gas treatment (named as slag phenomenon). When the biomass presents high levels of alkaline metals, like herbaceous and agro-industrial residues, these problems will be intensified. For example, the potassium and sodium decrease the melting point of the ashes, causing the incrustations and slag formation. On the other hand, magnesium and calcium in the biomass lead to the increase of the melting point of the ashes. The influence of the biomass quality on the bottom and fly ashes properties is related with the quantity of inert material, unburned carbon content and chemical composition. Thus, the main goal of this research work is focused on the characteristics of the forest biomass residues used as fuel in a Portuguese thermoelectric plant equipped with grate furnace technology. The results obtained allow the evaluation of the influence of some physical-chemical characteristics of the biomass on the produced ashes...

‣ Daily average exposures to respirable particulate matter from combustion of biomass fuels in rural households of southern India.

Balakrishnan, Kalpana; Sankar, Sambandam; Parikh, Jyothi; Padmavathi, Ramaswamy; Srividya, Kailasam; Venugopal, Vidhya; Prasad, Swarna; Pandey, Vijay Laxmi
Fonte: PubMed Publicador: PubMed
Tipo: Artigo de Revista Científica
Publicado em /11/2002 Português
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Indoor air pollution resulting from combustion of biomass fuels in rural households of developing countries is now recognized as a major contributor to the global burden of disease. Accurate estimation of health risks has been hampered by a paucity of quantitative exposure information. In this study we quantified exposures to respirable particulate matter from biomass-fuel combustion in 436 rural homes selected through stratified random sampling from four districts of Tamil Nadu, India. The study households are a subset of a larger sample of 5,028 households from the same districts in which socioeconomic and health information has been collected. Results of measurements for personal exposures to respirable particulate matter during cooking were reported earlier. This has been extended to calculation of 24-hr exposures with the aid of additional measurements during noncooking times and the collection of time-activity records. Concentrations of respirable particulate matter ranged from 500 to 2,000 micro g/m(3) during cooking in biomass-using households, and average 24-hr exposures ranged from 90 +/- 21 micro g/m(3) for those not involved in cooking to 231 +/- 109 micro g/m(3) for those who cooked. The 24-hr exposures were around 82 +/- 39 micro g/m(3) for those in households using clean fuels (with similar exposures across household subgroups). Fuel type...

‣ China - Biomass Cogeneration Development Project : Fuel Supply Handbook for Biomass-Fired Power Projects

World Bank
Fonte: World Bank Publicador: World Bank
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This handbook provides an overview of the main topics that need consideration when managing the supply of biomass to large biomass power plants. It will help investors in China to develop, with assistance of local biomass supply experts, their own solutions. The focus is on biomass residues, in particular agricultural residues (mainly straw and stalks) and forestry residues (mainly residues from forestry operations). This handbook covers a wide range of topics related to biomass fuel supply risk in the planning and preparation stages for a biomass-fired power plant. Chapter two introduces the use of biomass as an energy source, including fuel selection considerations and the fuel standards and specifications required to match a particular fuel supply to a power generation system. Chapter three describes the use of biomass resource assessments at the project planning stage. Chapters four and five give insight into the biomass supply from straw and forestry residues, respectively. Finally, fuel supply management is covered in chapter six...

‣ Timor Leste - Issues and Options in the Household Energy Sector : A Scoping Study

World Bank
Fonte: Washington, DC Publicador: Washington, DC
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The important role of biomass fuels today. Timor Leste is a relatively small country located in the eastern part of Timor Island with an area of about 1.5 million ha and an estimated 2007 population of 1.0 million. At about US$550 GDP per capita, it is one of the least developed countries in the world, with an estimated 40 percent of the population in poverty. However, the development of offshore oil and gas resources in partnership with Australia has recently begun to generate substantial revenues for the Government. The country still faces huge challenges ahead, as it tries to rebuild an economy that was totally devastated during the recent periods of violence and civil unrest. In the energy sector, several major investment projects have been initiated that would greatly expand the power generation and distribution infrastructure, and make electricity accessible to large numbers of currently un-served urban and rural people. For the household sector, there is no question that improved access to electricity will dramatically improve the quality of life...

‣ Output-Based Aid and Energy : What Have We Learned So Far?

Kumar, Geeta; Mumssen, Yogita
Fonte: World Bank, Washington, DC Publicador: World Bank, Washington, DC
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Worldwide, nearly 1.4 billion people live without access to electricity and nearly 2.7 billion people use traditional biomass fuels for cooking. One challenge to increasing reliable energy access for the poor is their limited ability to pay the up-front connection fees for electricity and natural gas. Output-based aid (OBA) approaches in which subsidy payments are linked to predefined outputs, such as installation of a working household connection or solar home system offers a potential solution that has increased energy access for more than 6.8 million poor beneficiaries. A recent World Bank review of OBA concludes that there is a case to adopt OBA more widely, where there is an enabling environment (Mumssen, Johannes, and Kumar, 2010). This note discusses lessons learned and best practices in implementing OBA in the energy sector.

‣ Addressing Household Air Pollution : A Case Study in Rural Madagascar

Dasgupta, Susmita; Martin, Paul; Samad, Hussain A.
Fonte: World Bank, Washington, D.C. Publicador: World Bank, Washington, D.C.
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Household air pollution is the second leading cause of disease in Madagascar, where more than 99 percent of households rely on solid biomass, such as charcoal, wood, and crop waste, as the main cooking fuel. Only a limited number of studies have looked at the emissions and health consequences of cook stoves in Africa. This paper summarizes an initiative to monitor household air pollution in two towns in Madagascar, with a stratified sample of 154 and 184 households. Concentrations of fine particulate matter and carbon monoxide in each kitchen were monitored three times using UCB Particle Monitors and GasBadge Pro Single Gas Monitors. The average concentrations of both pollutants significantly exceeded World Health Organization guidelines for indoor exposure. A fixed-effect panel regression analysis was conducted to investigate the effects of various factors, including fuel (charcoal, wood, and ethanol), stove (traditional and improved ethanol), kitchen size, ventilation, building materials, and ambient environment. Judging by its effect on fine particulate matter and carbon monoxide, ethanol is significantly cleaner than biomass fuels and, for both pollutants, a larger kitchen significantly improves the quality of household air. Compared with traditional charcoal stoves...

‣ Residential Market for LPG : A Review of Experience of 20 Developing Countries

Matthews, William G.; Zeissig, Hilmar R.
Fonte: World Bank, Washington, DC Publicador: World Bank, Washington, DC
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Of all the modern fuels available today, liquefied petroleum gas (LPG) is particularly well suited to domestic cooking and heating uses because of its clean-burning attributes and practical advantages over traditional biomass fuels as well as kerosene. LPG is more convenient in use and acquisition (e.g., no lengthy gathering or onerous bulk purchasing operations as with biomass), safer and cleaner. It has a high calorific value by volume and mass and uses high-efficiency end-use cooking apparatus. Households recognize these advantages and are usually prepared to pay a premium for LPG over other fuels if their incomes are high enough and LPG is available. Switching from traditional biomass fuels and coal to LPG can bring considerable health and environmental; benefits at the local, regional and global levels. Indoor air pollution, which affects mainly women and children, is greatly reduced. Switching to LPG can also reduce deforestation and free up supplies of dung for use as fertilizer and soil improver, enhancing agricultural productivity. The savings in time consumed gathering or acquiring bulk supplies of biomass fuels may allow householders to dedicate this time to pursue more productive activities...

‣ India : Access of the Poor to Clean Household Fuels

World Bank
Fonte: Washington, DC Publicador: Washington, DC
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There is a strong case for phasing out price subsidies for liquefied petroleum gas (LPG) and kerosene. This study was motivated by the primary objective of facilitating access to clean fuels, given the significant health and social benefits of switching away from traditional biomass. Price subsidies have been found to be ineffective in expanding the uptake of LPG and kerosene as primary household fuels among the poor, and have proven fiscally unsustainable. Even given this social objective, phasing out the price subsidies for LPG and kerosene, and fostering a vibrant, open, and competitive market for these fuels would appear to be a better approach. The conclusions of this study lend strong support to the announcement by the Ministry of Finance in June 2003, that the LPG and kerosene subsidies will be phased down in three years, and eliminated by April 2006. There are significant opportunities to facilitate a shift away from traditional biomass, to clean fuels in urban and peri-urban areas, including among the poor; however...

‣ Bolivia : National Biomass Program

World Bank
Fonte: Washington, DC Publicador: Washington, DC
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Over the past two decades, the Energy Sector Management Assistance Program (ESMAP) has financed several projects to assist Bolivia in the development of its energy sector, including the Bolivia Country Program First Phase, which contributed to the design of a national energy plan, the definition of policies and actions applicable to rural energy and energy efficiency, and a significant structural reform of the energy sector, and also supported the preparation of the Bolivia National Biomass Program (NBP) aimed at enhancing the efficient use of biomass as an energy source, while improving the quality of life of the rural population -- in consistence with the objectives of the World Bank Country Assistance Strategy (CAS) in Bolivia regarding accelerated growth and development of private sector activities. An agreement subscribed in November 1997 between the Government of the Netherlands and the World Bank assigned the execution of NBP to ESMAP, with the Vice Ministry of Energy and Hydrocarbons (VMEH) as its counterpart in Bolivia.

‣ Baseline and Feasibility Assessment for Alternative Cooking Fuels in Senegal

Practical Action Consulting; Enda; World Bank
Fonte: World Bank, Washington, DC Publicador: World Bank, Washington, DC
Tipo: Publications & Research :: Working Paper; Publications & Research
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This report was prepared by Practical Action Consulting for the Africa Clean Cooking Energy Solutions (ACCES) initiative of the World Bank. Most of Sub-Saharan Africa continues to rely overwhelmingly on traditional fuels and cooking technologies, both of which are a major cause of death and illness as well as a range of socio-economic and environmental problems. More than 90 per cent of the rural population of Senegal relies on solid fuels (charcoal and firewood in particular, but also dung and agricultural residues) to meet its household cooking needs. The primary objective of this study is, (a) to establish a baseline for the current level of penetration of four alternative cooking fuels in Senegal in a number of pre-identified regions, and (b) to assess the feasibility of adopting them in those regions. The four fuels are briquettes from charcoal dust and agricultural residues; ethanol, mainly from sugar cane residue (that is, molasses); pure plant oil (PPO) from locally grown, oil-bearing plants such as Jatropha curcas; and a household biogas system using mainly livestock waste. Against this background...

‣ Restoring Balance : Bangladesh's Rural Energy Realities

Asaduzzaman, Mohammad; Barnes, Douglas F.; Khandker, Shahidur R.
Fonte: World Bank Publicador: World Bank
Tipo: Publications & Research :: Publication; Publications & Research :: Publication
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Bangladesh is one of the world's poorest countries. Nearly 80 percent of the nation's 140 million people reside in rural areas; of these, 20 percent live in extreme poverty. Geographically, many low-lying areas are vulnerable to severe flooding, while other regions are prone to drought, erosion, and soil salinity. Such an unfavorable agricultural landscape, combined with mismanagement of natural resources and increasing population pressure, is pushing many of the rural poor to the brink. Because Bangladesh is such a poor country, it also is one of the world's lowest energy producers. Total annual energy supply is only about 150 liters of oil equivalent per capita (International Energy Agency, or IEA 2003); in rural areas, conditions are even worse. Compared to other developing countries, Bangladesh uses little modern energy. Despite its successful rural electrification program, close to two-thirds of households remain without electricity and, with the exception of kerosene, commercial fuels are beyond reach for many. Moreover...

‣ Household Energy Access for Cooking and Heating : Lessons Learned and the Way Forward

Ekouevi, Koffi; Tuntivate, Voravate
Fonte: Washington, DC: World Bank Publicador: Washington, DC: World Bank
Tipo: Publications & Research :: Publication; Publications & Research :: Publication
Português
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Half of humanity about 3 billion people are still relying on solid fuels for cooking and heating. Of that, about 2.5 billion people depend on traditional biomass fuels (wood, charcoal, agricultural waste, and animal dung), while about 400 million people use coal as their primary cooking and heating fuel (UNDP and WHO 2009). The majority of the population relying on solid fuels lives in Sub-Saharan Africa and in South Asia. In some countries in Central America and in East Asia and the Pacific, the use of solid fuels is also significant. The inefficient and unsustainable production and use of these fuels result in a significant public health hazard, as well as negative environmental impacts that keep people in poverty. Strategies to improve energy access to the poor have focused mainly on electricity access. They have often neglected non electricity household energy access. It is, however, estimated that about 2.8 billion people will still depend on fuel wood for cooking and heating in 2030 in a business-as-usual modus operandi (IEA 2010). The need for urgent interventions at the household level to provide alternative energy services to help improve livelihoods is becoming more and more accepted. This report's main objective is to conduct a review of the World Bank's financed operations and selected interventions by other institutions on household energy access in an attempt to examine success and failure factors to inform the new generation of upcoming interventions. First...

‣ Improving Indoor Air Quality for Poor Families : A Controlled Experiment in Bangladesh

Dasgupta, Susmita; Huq, Mainul; Khaliquzzaman, M.; Wheeler, David
Fonte: World Bank, Washington, DC Publicador: World Bank, Washington, DC
Tipo: Publications & Research :: Policy Research Working Paper; Publications & Research
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The World Health Organization's 2004 Global and Regional Burden of Disease Report estimates that acute respiratory infections from indoor air pollution (pollution from burning wood, animal dung, and other bio-fuels) kill a million children annually in developing countries, inflicting a particularly heavy toll on poor families in South Asia and Africa. This paper reports on an experiment that studied the use of construction materials, space configurations, cooking locations, and household ventilation practices (use of doors and windows) as potentially-important determinants of indoor air pollution. Results from controlled experiments in Bangladesh are analyzed to test whether changes in these determinants can have significant effects on indoor air pollution. Analysis of the data shows, for example, that pollution from the cooking area diffuses into living spaces rapidly and completely. Furthermore, it is important to factor in the interaction between outdoor and indoor air pollution. Among fuels, seasonal conditions seem to affect the relative severity of pollution from wood...

‣ Energy Policies and Multitopic Household Surveys : Guidelines for Questionnaire Design in Living Standards Measurement Studies

O'Sullivan, Kyran; Barnes, Douglas F.
Fonte: Washington, DC : World Bank Publicador: Washington, DC : World Bank
Tipo: Publications & Research :: Publication; Publications & Research :: Publication
Português
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Analysis using data on household energy use from Living Standards Measurement Study (LSMS) surveys can help policymakers to identify which households are affected by energy poverty and then design policies that will accelerate the household energy transition. This paper shows that LSMS can provide accurate data on household energy use, combined with other data on household wellbeing (including consumption, income, health, and education), to monitor the progress in the household energy transition from traditional biomass fuels to modern fuels and electricity and to evaluate the effect of government energy policies on living conditions.

‣ Emission of Metals from Pelletized and Uncompressed Biomass Fuels Combustion in Rural Household Stoves in China

Zhang, Wei; Tong, Yindong; Wang, Huanhuan; Chen, Long; Ou, Langbo; Wang, Xuejun; Liu, Guohua; Zhu, Yan
Fonte: Nature Publishing Group Publicador: Nature Publishing Group
Tipo: Artigo de Revista Científica
Publicado em 08/07/2014 Português
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Effort of reducing CO2 emissions in developing countries may require an increasing utilization of biomass fuels. Biomass pellets seem well-suited for residential biomass markets. However, there is limited quantitative information on pollutant emissions from biomass pellets burning, especially those measured in real applications. In this study, biomass pellets and raw biomass fuels were burned in a pellet burner and a conventional stove respectively, in rural households, and metal emissions were determined. Results showed that the emission factors (EFs) ranged 3.20–5.57 (Pb), 5.20–7.58 (Cu), 0.11–0.23 (Cd), 12.67–39.00 (As), 0.59–1.31 mg/kg (Ni) for pellets, and 0.73–1.34 (Pb), 0.92–4.48 (Cu), 0.08–0.14 (Cd), 7.29–13.22 (As), 0.28–0.62 (Ni) mg/kg for raw biomass. For unit energy delivered to cooking vessels, the EFs ranged 0.42–0.77 (Pb), 0.79–1.16 (Cu), 0.01–0.03 (Cd), 1.93–5.09 (As), 0.08–0.19 mg/MJ (Ni) for pellets, and 0.30–0.56 (Pb), 0.41–1.86 (Cu), 0.04–0.06 (Cd), 3.25–5.49 (As), 0.12–0.26 (Ni) mg/MJ for raw biomass. This study found that moisture, volatile matter and modified combustion efficiency were the important factors affecting metal emissions. Comparisons of the mass-based and task-based EFs found that biomass pellets produced higher metal emissions than the same amount of raw biomass. However...

‣ Uncovering Barriers to Domestic Biomass Investment

Stroud, William; Gupta, Karan
Fonte: Universidade Duke Publicador: Universidade Duke
Tipo: Masters' project
Publicado em 04/12/2015 Português
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Wood has been used as an energy source for hundreds of thousands of years, and even today, accounts for 10% of the global total primary energy supply. Though traditional uses such as heating and cooking are the most common applications of woody biomass today, modern heat and power applications such as district heating, industrial process heating, and electric power generation show great promise. Despite the development of efficient technologies, abundant forest resources, and widespread adoption in Europe, the use of woody biomass for heat and power in United States has not been widely adopted. Through a series of interviews with general industry stakeholders, as well as more targeted interviews with operations and fuel managers at biomass facilities currently in service, this report seeks to address the central research question, “What are the barriers to investment in domestic biomass facilities?” From interview responses, the most prevalent barriers to increased adoption included the low price of natural gas, logistical constraints around collecting, transporting, and processing biomass fuels, negative public perception, inconsistent policies around biomass utilization, and scientific uncertainty around the environmental impacts of biomass. To overcome these barriers...

‣ Characteristics of potential gasifier fuels in selected regions of the Lake Victoria Basin

Mosiori,Geoffrey O.; Onindo,Charles O.; Mugabi,Paul; Tumwebaze,Susan B.; Bagabo,Samuel; Johnson,Rukundo B.
Fonte: South African Journal of Science Publicador: South African Journal of Science
Tipo: Artigo de Revista Científica Formato: text/html
Publicado em 01/06/2015 Português
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All countries in the Lake Victoria Basin depend mostly on hydroelectric power for the provision of energy. Gasification technology has a high potential for reducing biomass energy consumption whilst increasing access to modern energy services. The key aspect for the failure of gasification operations in the Lake Victoria Basin is inadequate adaptation of gasification equipment to fuel characteristics, lack of fuel specification and inappropriate material choice. We therefore investigated the thermo-chemical characterisation of six biomass fuels, namely Pinus caribaea, Calitris robusta, Cupressus lusitanica, Eucalyptus grandis, Pinus patula and sugarcane bagasse from selected regions of the Lake Victoria Basin. Ultimate analysis was done using a Flash 2000 elemental analyser. Moisture content, ash content and volatile matter were determined in oven and muffle furnaces while heating values were determined using a Gallenkamp calorimeter. The mean percentage levels obtained indicate that all six biomass fuels had a mean range for nitrogen of 0.07±0.2-0.25±0.07%, for carbon of 40.45±0.61-48.88±0.29%, for hydrogen of 4.32±0.13-5.59±0.18% and for oxygen of 43.41±1.58-51.1±0.64%. Moisture content ranged between 25.74±1.54% and 56.69±0.52%...