Exploring Biofuels: Types, Uses, and Environmental Impact

1. BIOFUELSCarlos SousaAGENEAL, Local Energy Management Agency of Almada

2. SUMMARY • Definition of Biofuels • Types of Biofuels • Characteristics of Biofuels

3. 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.

4. 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.

5. TYPES OF BIOFUELS • The two main biofuels are: • Bioethanol, as a substitute or additive for petrol; • Biodiesel, as a substitute for diesel;

6. BIODIESEL

7. 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

8. 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

9. 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

10. 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

11. 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)

12. 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!!

13. BIOETHANOL AND THE ENVIRONMENT

14. 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.

15. 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

16. Thank you for your attention!