biofuels Flashcards
biofuels
renewable liquid fuel made from biomass
the types depend on how they are made and the material it is made from
ethanol and biodiesel
biomass
collective term refering to crops, plant residue, organic waste or anything from a living thing
ethanol
typically made from sugars found in grains such as corn barley and sorghum
generally used as replacement for petrol in cars and other tech systems that use petroleum
biodiesel
made from veg oils, animal fats, cooking grease
used to replace petrol based diesel in compression ignition engines
no modifications are needed for dieseil engines for biodisel to be put in
PROS of biofuels
non toxic
carbon neutral - as plants used to make biofuels are regrown and the new plants reabsorb CO2 released by burning of biofuels
allow for less dependence on imported petroleum
CONS of biofuel
amount of energy produced by biofuels is not enough to replace fossil fuels without making most of planets non urban land into farmland to make crops for biofuel
use of biofuel can create competition for land between crops and fuel
not all biofuels are carbon neutral
biofuels from grains produce same carbon emisson as fossil fuels
fossil fuels
fuels derived from remains of dead organisms that lived millions of years ago
oil, coal, natural gas, tar, bitumen
non renewable as process to form them requires millions of years making them impossible to replenish over typical human civilisations
oil and advatnages
liquid substance made of hydrocarbon that once was made of living organisms
source of gasoline and other liquid fuels to power land vehicles/aircrafts so its important for transportation
high energy density
oil disadvantages
extraction methods are hazardous to natural environment
oil spills are destructive to animals, plants and environment
burning of oil releases particles which affect lungs of human beings and animals and releases lots of CO2 adding to global warming
coal and advantages
consists of solid mass of hydrocarbons produced from heat and pressure. forms from dead plants
important in industrial revolution
cheap power source
used for electricity generation
coal disadvantages
one of the most environmentally harmful fossil fuels
extraction of coal destroys large amounts of vegetation + contaminates river with toxic mine waste
burning of coal produces mercury, SO2, nitrogen oxides causing acid rains
contributes to CO2 emissions
natural gas
used for heating and electricity
cleaner, low carbon alternative to other fossil fuels
burning of natural gas produces less CO2 and less pollutants than burning oil or coal
