Biomass Energy Resource

Dr. Akepati S. Reddy

Thapar University

Patiala (Punjab) – 147 004

INDIA

Biomass Energy Resource

PlantPhoto-

synthesis

Heterotrophic consumption

Biomass lostas litter

Biomass accumulated

UnutilizedSolar radiation

Photosynthate for auto-oxidation

Food & fodder

Energy resource

Input to industryfor fiber and lumber

Solar Radiation

Biomass - solar energy with inbuilt storage option

Plant derived organic matter available on a renewable basis

Ultimate Sources for Biomass: Harvesting Removal and SustainabilityUltimate sources for different forms of bio-energy sources• Natural ecosystems (forests)• Agricultural systems (including animal husbandry)• Energy forestry/cropsBiomass produced through photosynthesis has the following fates• Heterotrophic consumption (feeding the grazing food chain)• Addition to the detritus food chain• Accumulation as standing biomass• Harvesting removal of biomassBiomass is harvested for using as• food and fodder; • Timber, fiber and other industrial raw materials• Energy resourcesLeaving enough biomass for heterotrophic consumption, for

addition to detritus food chain and for accumulation are important for

• Soil texture and structure and soil fertility• Biodiversity• Life supporting ecological functions• Systems’ sustainability and stability

Biomass Energy Resources• Wood fuels

– Fuel wood (and charcoal)– Forest residues– Wood residues from wood processing industry– Recycled wood from society (construction and demolition

waste)• Agricultural residues

– Crop residues– Animal dung and livestock residues

• Agricultural produce– Cane juice, grains, potatoes, vegetable oils, etc.

• Industrial wastes– Black liquor from pulp mills– Bagasse, molasses and spent wash from sugar and distillery

industry – Byproducts and wastes from food industry

• Energy forestry/crops• Aquatic and other weed biomass• Municipal wastes

– Municipal solid wastes– Municipal sewage and sewage sludge

Biomass as Energy ResourceBiomass is a versatile fuel • Can be stored and transported and can be converted into quality

gaseous, liquid & solid fuels & electricity• If used sustainably, no net release of CO2 • <1% of productivity is used - meets 15% of total energy demandBiomass has alternative non-energy uses - as food and fodder –

as industrial raw material – as soil conditioner and nutrient enricher – can deprive land from other competitive uses

Residential use as firewood/ char coal • Half of harvested wood (75% in sub-Saharan Africa)• Scarcity for 100 million & no sustainable supply for 1.2 billion • Key producers - India, Brazil, China, Indonesia, USA & NigeriaBiomass as energy in industry - Burning in boilers and

cogeneration units - Gasification and gas turbinesBiomass use in transportation activity • Production & use of ethanol (10,500,000 Kl by Brazil in 1986)• Food surpluses for ethanol (sugar and corn)

Use of Biomass Fuel ResourcesUse of biomass fuels in industrial countries • for electricity generation, in space-heating boilers, small

industrial applications and decentralized applicationsUse of biomass In developing countries • main source of energy for many artisan and cottage industries• In brick kilns and lime kilns; for drying and smoking of

agricultural produce and fish; for supply of charcoal for high grade smelters

• to produce charcoal for consumption in heavy industry (iron & steel, cement, etc.)

Use is for providing heat and/or generating electricity• Direct combustion of biomass or co-firing as supplementary

fuel in coal fired boilers• Converting into fuels and then combusting (use of combined

cycles or fuel cells)Use involves harvesting, collection, transportation, storage,

handling, conveyance, size reduction, cleaning, drying and feeding operations - all these require infrastructure and logistics

Biomass Energy Resources: StatusBiomass energy potential of the earth is the largest of sustainable

energy sourcesAnnual biomass production is 2x1011 tons (4x1021 J) and standing

biomass of the earth is 36x1021 J (photosynthetic efficiency of solar radiation is 0.27%)

Energy contribution by biomass today is 55 EJ (while total energy consumption is 400 EJ) – it may raise to 59-145 EJ by 2025 and to 94-280EJ by 2050

The Role of Biomass in Future Global Energy Use (EJ) – can be used both as a traditional fuel and as a modern fuel

Non-availability of biomass energy resource is not a problem – sustainable management and proper delivery of the energy resource are the problems

2025 2050 2100

Shell (1996) 85 200-220 ----

IPCC (1996) 72 280 320

Green peace (1993) 114 181 ----

WEC (1993) 59 94-157 132-215

Johansson et al. (1993) 145 206 ----

Dessus et al. (1992) 135 ---- ----

Lashof and tirpak (1991) 130 215 ----

Energy consumption• Rural biomass energy consumption – one ton per capita year

(15% moisture wood) – equivalent to 15 GJ energy• Urban and sub-urban energy consumption – 0.5 ton/capita year• Biomass energy consumption trends in India between 1978/79

and 1992/93• Number of households using biomass energy decreased

from 97% to 94%• Overall firewood consumption increased from 42 to 47%• Households collecting firewood decreased (from 35 to 17%• Collection biomass fuels from own farms however has

increased significantlyIn European union biomass supplied 3% (45mtoe) of the primary

energy demand, and by 2010 it may raise to 135 mtoe

Biomass Energy Resources: Status (contd..)

Biomass Fuels: Environmental IssuesTraditional biomass energy is blamed for environmental

degradation and health hazards• Large scale deforestation as a consequence of increased fuel

wood and charcoal demands• 90% of human exposure to SPM occurs in developing countries

and 2/3rd of this occurs in the rural areas that too indoors

Most of the biomass energy problems are associated with • unsustainable production of biomass • inefficient use of biomass

Sustainable production and efficient use of biomass energy can eliminate most of the problems and make biomass fuels environmentally beneficial

• Depending on scattered trees of farms, agro-forestry and energy crops for meeting most of the fuel wood and charcoal needs

• Improving efficiency, safety and cleanliness – gathering and carrying biomass fuels – installation of biomass fuels

• Sustainable use of biomass fuels can result in neutral CO2 emissions

• Use of ethanol, bio-diesel, etc., can reduce carbon emissions, and toxicity from lead additives and aromatic hydrocarbons

• Bioenergy technologies are more environmental friendly (reduce SO2 and NOx emissions)

Biomass production can influence the following:• Soil erosion and soil nutrient retention• Carbon sequestration • Stabilization of river banks• Watershed stability • Ground water quality • Surface water runoff and quality• Local water use for crop irrigation and/or conversion facility

needs• Bring about changes in habitat and in the levels of biodiversity

Biomass Fuels: Environmental Issues (contd..)

Low prestige is attached with traditional biomass fuelsBiomass energy is viewed as a non-commercial rural energy

source and not as a modern clean competitive energy source with potential for commercial possibilities• Biomass densification• Charcoal making• Improved cooking stoves• Biomass and biomass based fuels may be considered as

technically mature, environmentally sound, economically viable and culturally acceptable options for modern energy development around the world

Land availability and possible competition with food production is a major concern• Bioenergy production can be complimentory to food

production• Degraded and abandoned lands can be used to establish

environmentally sustainable biomass plantations

Biomass Fuels: Socio-economic Issues

– For meeting all the present energy consumption needs from biomass 950 million hectares of land may be required in industrial countries and 365 million hectares in developing countries – 12 ton/hec.yr. is assumed as productivity and 25% of the productivity will be used as biomass energy

– Arable land should be used in a balanced way for supporting a) Agriclutural and forestry production; b) Environmental preservation; c) Human and wildlife habitats and d) Biomass production

Bioenergy will reduce dependence on fossil fuels and ensures energy security (more evenly distributed) through reducing dependence on imported oils and ensuring energy self sufficiency

Bioenergy can stimulate rural developmentPrime concern should be distribution of wood fuels to people

Biomass Fuels: socio-economic Issues (contd..)

Reasons for Growing Interest in Biomass

• Rapid changes in the energy market worldwide, driven by privatisation, deregulation and decentralisation

• Greater recognition of current role and future potential of biomass as a modern energy resource and general interest in other renewables

• Its availability, versatility and sustainability• Better understanding of its global and local environmental

benefits and perceived potential role in climate stabilisation• Existing and potential development and entrepreneurial

opportunities• Technological advances and knowledge evolved on many

aspects of biomass energy and other RE

Factors that are Favouring Development of Biomass Energy

• Growing concern with global climate change and firmly established support for RE

– Growing recognition of the importance of biomass energy - World Bank supports energy policies that are as concerned about supply and use of biofuels as about modern fuels supports use biofuels more efficiently and sustainably"

• Expected increases in energy demand and current rapid growth of RE

– Global Environmental Facility (GEF) predicts demand of 5 million MW new power generation capacity in next 40 years in developing countries and most of it could be from RE

– Two billion people who lack reliable energy and have little prospect of connecting to grid, RE is among the best options

• More and more countries are introducing policies in support of RE, with biomass energy playing a central role

• Environmental pressures will increase price of fossil fuels – with internalization of costs RE will become comparable to fossil fuels

• Technology is evolving rapidly (advances in gasification, co-firing, biogas production, etc.) and biomass is finding growing number of modern applications (electricity generation, ethanol fuels blended with gasoline, biodiesel, etc.)

Fuels from BiomassBiofuels – Bioconversion of biomass into ethanol, methanol,

biodiesel, biogas, etc., fuels • Ethanol production: conversion of carbohydrate portion of

biomass first into sugar and then into ethanol through fermentation

• Anaerobic digestion of biomass to produce biogas (Biomass decay to produce landfill gas or biogas)

• Hydrogen: photosynthetic activity of bacteria and green algae can produce hydrogen from water and sunlight

Pyrolytic fuels (exposure of biomass to high temperature in the absence of air to obtain mixture of solid, liquid & gases fuels)

Fuels from thermo-chemical and catalytic conversion of biomass: charcoal, methanol, fischer-tropsch diesel, etc.

• Charcoal through carbonization of biomass - 12-25% efficient, but in Brazil it is 30-35% efficient

• Methanol production through gasification of biomass into synthetic gas (CH4, H2 and CO) and catalytic conversion of methane of this gas into methanol

• Conversion of biomass into Fischer – Tropsch diesel through using Fischer-Tropsch catalyst

Bio-refineries – fractionation of biomass into an array of products like sugars, cellulose fibers and lignin through use of solvents, acids and bases

Bio-fuelsEthanolAs fuel in the transportation activity Brazil and USA are pioneers Sugar cane and corn are used as raw materialsBrazil’s alcohol production program was started in 1975 and

peaked in late 1980s and showed decline in 1990s - at peak replaced 250,000 barrels/day of imported oil - 5 million vehicles on pure bio-ethanol and 9 million on 20-22% gasohol

USA produced 5.3 billion liters of ethanol in 1994 and additional 0.9 billion liters capacity was under construction - gasohol sale amounts to 10% of the total fuel - future plans are to produce 9 billion liters in 2005 and 85 billion liters in 2030

Bio-dieselVegetable oils combined with alcohol (ethanol or methanol) in the

presence of a catalyst to form ethyl or methyl ester (biodiesel) - animal fats, algae or recycled cooking greases can also be used

Vegetable oil mixed with diesel can be used in special diesel engines as fuel; and trans-esterified plant oil mixed with diesel for normal diesel engines

• Austria produces 30,000 tons (supplies 5% of the diesel market); France 20,000 tons and Italy 60,000 tons of trans-esterified plant oils

• USA has a bio-diesel board and it uses B20 fuel (20% biodiesel/conventional diesel blend)

Biogas (generated from treatment of animal manure and other organic wastes (agricultural residues & municipal solid wastes)

• Denmark – Stands at forefront – has 18 centralized large commercial

plants producing 40-45 million m3/yr of biogas and consuming 1.2 million tons of biomass

– Total current annual biogas energy production was 2 PJ in 1996 - may rise to 4 PJ by 2000 and to 6 PJ by 2005

• China– Biogas production was 33 PJ in 1995– has 5.25 million household biogas plants and 600 large &

medium biogas plants – has 24,000 biogas purification digesters and 190 biogas

based power plants of 3 GWh generation capacity • India

– India has National Program of Biogas Development for providing clean cooking energy, producing enriched manure, improving quality of life of rural women, and improving sanitation and hygiene

– In 1993 there were 1.85 million household biogas plants against the potential for 12 million plants - 1.2 million of these were operational (!)

Bio-fuels (contd..)

Wood Fuels Production (in 1999)Region Forest area*

in 99 (x103 km2)Production

in 96 (x106 ton)Production

in 99 (x106 ton)

Africa 6,499 (21.3%) 384.1 428.3North America 5,493 (25.7%) 123.5 116.8South America 8,742 (49.9%) 124.2 114.4Asia 5,369 (21.1%) 684.4 656.0Europe 10,392 (46.0%) 95.6 105.9Middle East 110 (2.05%) 2.6 0.7Oceania 2,011 (23.7%) 11.6 11.6Total world 38,616 (29.6%) 1426.0 1433.7India 641 (21.6%) 202.5 203.5

* Additional 1.7 billion hectares has tree or woody vegetation cover

Wood EnergySources include forests, trees outside forests, residues from wood

processing industries and recycled wood from societyWorldwide in 1999 was 470 mtoe (1.4 billion ton) was consumed

as fuel (about 50% of the total wood harvested) – it amounts to 5% of the world’s total energy demand

• In 1996 world production of wood for energy was 1.4 billion tons - 0.3 billion tons of it was recycled wood

• Forests contain 440 billion oven-dry tons of woody biomass - annual use as energy is about 0.3% of this stock (within the renewable limits) – but in India 2.5% of the stock is used

Considerable fraction of wood comes from non-forest sources in countries like, Indonesia, Sri Lanka, Pakistan, Bangladesh, Philippines, Thailand & India - >50% is from non-forest sources)

Energy plantations on waste lands using new genetic material for high productivities

Forests in industrial countries are either stable or are showing slight increase, but in developing countries they are lost at the rate of 12 million hec./yr.

Consumption of Wood Fuels Wood contributes 6-7% of global primary energy supply

• 3% in europe and North America• 1.5% in industrial countries • 2-3% in former soviet union • 10-15% in the developing countries of Asia & Latin America • 33% in africa (if South Africa, Egypt and Algeria are

excluded its contribution is 60%)World’s average per capita annual wood consumption is 0.1ton

• North America 0.25• Africa and Latin America 0.15• Asia Pacific 0.07

Wood is inconvenient fuel if put to traditional uses (inefficient and highly polluting)

Wood is laborious and bulky to harvest, transport and storeWood use has tripled over the last 50 yearsLow income, unequal distribution of income and relatively low

urbanization are found increasing reliance on woodWood is used both as a necessity or as a luxury (in charcoal

barbecues and traditional open log fires)

Consumption of Wood Fuels

Wood fuels• Varies from region to region (depends on developmental stage

and high for rural areas of developing countries)• World per capita consumption is 0.3 to 0.4 m3/yr. (0.77 for

Africa and 0.5 for certain Asian countries (Nepal, Cambodia, Thailand and Indonesia)

• Contribute 5% of the world’s total primary energy demand (40% for Africa – 60-80% for certain countries; 10% for Latin America; 7% for Asia; 41% of the total inland primary energy supply for India; 1.2 and 1,4% for Europe and North America respectively)

• Consumption in some areas exceeds sustainable production (only 8.3% of total wood fuel supply in India)

• Share of wood fuels in the national energy balance is progressively decreasing, but increasing in absolute terms

Charcoal• Burns efficiently and easy for storage and transportation – but

production consumes 6m3 of wood fuel per ton• Large scale industries use wood fuels in the form of charcoal

(steel & alloy production in Brazil uses 6 million ton/yr.)• Charcoal is preferred over wood fuel in and around urban areas

Household consumption58% and 82% of the total rural household energy consumed in

Pakistan and Philippines is from wood fuelIn European Union, household consumption is 60% of the total

wood fuel consumed; for Africa it is 86% (in sub-sharan countries it is 90 to 98%)

Major household use of wood fuel is for cooking and water heating – (in Indian urban households 86% is consumed for cooking and the rest for water heating)

Traditional industrial consumption

Mostly by rural industry, specially rural agro-based industry (amounts to 10-20% of the total wood fuel consumed in certain Asian countries)

Consumption of Wood Fuels (contd..)

Other Biomass Energy ResourcesMunicipal solid waste • Has disposal problems and contains different organic and

inorganic components • MSW can be sorted into biodegradable waste, plastic waste and

metallic waste, but sorting is costly and difficult• Biodegradable waste can be treated for biogas recovery and

then converted into peat mass

Bagasse from sugar industry• World wide 200 million tons of bagasse was produced in 1995• In brazil cogeneration using bagasse as fuel represents 9000

MW (year round) – if ethanol distilleries are also considered, after excluding internal consumption, sugar industry’s energy generation capacity is 6000 MW

• Year round generation of power requires storage of bagasse• India has 2800 to 5100 MW cogeneration potential – in 1994

only 3 mills were generating 5 MW power – in 1997 there were 16 mills with capacity to 56MW.

Miscellaneous

Modern biomass energy sources – fuel wood crops; agricultural residues and wastes – may contribute 4-8 billions in the next century and raise the share of biomass to 20% in the primary energy supply

Improving efficiencyUsing in an environmentally sound manner and sustainable

mannerBy 2010 power generation from straw, saw dust and bagasse in

china will reach 300 MWBiomass gasification technologies are evolving - In 1990s there

were 8-15 MW capacity plants; by 2000 the capacity will be 20-30MW and by 2005 the capacity will be 50-80 MW

Forestry residues from pulp & paper and timber industryStraw from agricultural fields