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BIOFUELS Carlos Sousa AGENEAL, Local Energy Management Agency of Almada. SUMMARY. Definition of Biofuels Types of Biofuels Characteristics of Biofuels. DEFINITION OF BIOFUELS. Biofuels are liquid fuels, which are made from a variety of sources of biomass: plant materials types of crops
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BIOFUELSCarlos SousaAGENEAL, Local Energy Management Agency of Almada
SUMMARY • Definition of Biofuels • Types of Biofuels • Characteristics of Biofuels
DEFINITION OF BIOFUELS • Biofuels are liquid fuels, which are made from a variety of sources of biomass: • plant materials • types of crops • recycled or waste vegetable oils • Biofuelscan be used in internal combustion engines, as a replacement or complement of petrol and diesel.
BIOFUELS • Reasons for promoting biofuels are: • To contribute to the security of energy supply; • To contribute to the reduction of greenhouse gas emissions; • To promote a greater use of renewable energy; • To diversify agricultural economies into new markets.
TYPES OF BIOFUELS • The two main biofuels are: • Bioethanol, as a substitute or additive for petrol; • Biodiesel, as a substitute for diesel;
BIODIESEL • Biodiesel is a general name for methyl esters from organic feedstock. • Biodiesel can be made from a wide range of vegetable oils: • rapeseed – the most common one • sunflower • palm oil • soy • recycled cooking oils • Germany and France are the largest EU producers
USE OF BIODIESEL • Biodiesel can be used pure or blended. • Most common blends is 5% biodiesel, 95% diesel • Blends above 5% may invalidate manufacturers warranty • Blends above 30% may require modifications in the engine • rubber seals perishing and injectors blocking
BIODIESEL AND THE ENVIRONMENT • Use of 100% biodiesel would reduce “life-cycle” CO2 emissions by 40 to 50%. • But, this is not common… • …Use of 5% blend reduces CO2 emissions by 2 to 2.5%. • Biodiesel is biodegradable
BIOETHANOL • Bioethanol is a alcohol produced from the fermentation of: • sugarcane and corn: Brazil and USA • sugar beet or wheat: Europe, mainly Spain, Poland and France are the main producers • Technology to produce bioethanol from cellulosic materials (agricultural and wood wastes) and separated domestic wastes is not yet well developed
BIOETHANOL • A 5% blend of Bioethanol does not require vehicle modifications, nor affects manufacturers warranty. • Substitute for MTBE in petrol (octane enhancer) • Flexible Fuelled Vehicles, FFV, can use higher concentrations of bioethanol • Ford, Volvo and Saab sell FFV (blend of 85% bioethanol and 15% petrol)
USE OF BIOETHANOL • The energy content of bioethanol is about two-thirds that of petrol • Consumption is higher (volume) • Bioethanol is an alcohol – contains oxygen (C2H5OH) • Need to adjust air/fuel ratio – modern engines do it up to 10% bioethanol blends • Bioethanol has a higher latent heat of evaporation • poorer cold start ability in winter. Petrol may need to be used for start • Bioethanol is an octane enhancer • Higher compression ratios may be used – More efficiency!!
BIOETHANOL AND THE ENVIRONMENT • For 100% bioethanol the reductions are typically 50 to 60% on a “life-cycle” basis compared with conventional fossil fuels. • 5% blends would bring approximately 2.5 to 3% net reductions.
BIOFUELS – ECONOMIC ASPECTS • Producing biodiesel from oil seeds costs about twice as much as diesel from crude oil • Producing bioethanol costs about 2-3 times as much as petrol from crude oil • Thus… • Duty reductions or exemptions are necessary