Slides in this set
What is a biofuel?
· A biofuel is any fuel made from biological
Carbon fixation. (Biomass, biogas)
· Although fossil fuels have their origin in
ancient carbon fixation, they are not
considered biofuels because they contain
carbon that has been "out" of the carbon cycle
for a very long time.
· This ppt will focus more in depth on
Bioethanol and Biodiesel…read more
· Bioethanol is an alcohol made by fermentation.
The enzyme carbohydrase is added to maize, corn or another
This extracts sugars which are then fermented to produce ethanol.
The ethanol is then distilled and is ready to be used as a fuel.
· It burns to produce carbon dioxide and water, and is a high octane fuel.
· It can be added to petrol to oxygenate it, meaning it burns to produce
carbon dioxide, rather than the more harmful carbon monoxide.
· If it is in a small percentage against petrol (10%) it can run in an unmodified
· It is biodegradable, harmless if spilt, renewable and produces `cleaner'
· It is `Carbon Neutral' in that the carbon emissions created during production
and combustion are counteracted by the Carbon dioxide used by the
plants it is made from.…read more
· Made from plant oils such as rapeseed oil.
· These are reacted with alcohol to form fatty esters.
· They can be used in standard diesel engines.
· It can be used neat or blended with fossil diesel.
· It can be made from waste vegetable oil sourced in chip
shops, restaurants and industrial food production sites.
· It is also `carbon neutral' and renewable.
· Biodiesel is biodegradable and completely non-toxic, meaning
spillages are far less risky than fossil diesel spillages. It also
has a higher flash point than fossil diesel and so is safer in the
event of a crash.…read more
· There are many obvious advantages of biofuels but there are
also some cons.
· Many LEDCs make money by producing the plants used to
make biofuels. However this is taking up space needed for
food, which many of these countries don't have enough of.
· There are many steps in the process which increase costs and