biofuels - pack 16

Question 1

what is a biofuel

Answer 1

any source of energy produced directly in plants or indirectly in animals by recent photosynthesis

Question 2

describe how biofuels are both a renewable energy source and carbon neutral

Answer 2

when wood burns the co2 released to the atmosphere replaces the co2 previously absorbed through photosynthesis which would have eventually been released through the process of decay

Question 3

why could biofuels not be considered to be carbon neutral

Answer 3

co2 is released in the process of transporting the biofuel from where it is made to where it is used

Question 4

examples of biofuels

Answer 4

wood, straw, dried chicken litter, vegetable oil, methane

Question 5

why are the production of biofuel using palm oil and edible corn not viable options

Answer 5

• the destruction of rainforests to plant palm oil trees for biofuel is releasing vast amounts of stored carbon into the atmosphere, cancels out any gains from burning biofuels and also harming wildfire
• use of large quantities of edible corn to make corn oil and ethanol for biofuel affects food availability

Question 6

what is methane produced from

Answer 6

anaerobic fermentation of human sewage, domestic waste, animal spurn

Question 7

what are domestic waste and animal slime referred to

Answer 7

as biogas and when burned is co2 neutral