Monday - Day1
Bioenergy & Biofuels
Renewable Energy Resources
Objectives:
• What are the different forms and sources of
energy
• What sources of energy are renewable or nonrenewable energy?
• What is Bioenergy? What is Biomass? Biofuels?
• Making Biodiesel
• Collecting Biogas
Classifying Energy Forms
Potential
• Gravitational Potential –
energy due to the position
of an object.
• Chemical Potential –
energy present within the
chemical bonds of a
substance.
• Elastic potential – energy
of a stretched or
compressed object.
• Nuclear potential –
energy of particles inside
an atomic nucleus.
Kinetic
• Radiant solar energy –
the motion of EMR
• Sound energy – the
motion of sound waves
• Electrical energy – the
motion of flowing electrons
• Thermal energy – the
motion of particles
Sources of Energy: How do we Produce
Energy for our Needs?
Originate From Solar Energy
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Direct solar (e.g.
photovoltaic panels)
Biomass (e.g.
wood, manure,
ethanol)
Hydro
Wind
Fossil fuels (coal,
natural gas,
petroleum)
Do NOT Originate from Solar Energy
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Tidal and
wave
Geother
mal
Nuclear
fission
Renewable vs. Non-Renewable Energy
& Energy Transformations
• What are the differences?
– Non-renewable energy sources:
• are extracted from the Earth as resources that are
finite and may last, at most, for a few hundred
years
– Renewable energy sources:
• are continuously replenished or renewed by
energy from the Sun
• are considered renewable because they will last
indefinitely
Bioenergy
&
Biofuels
New English Words
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Bioenergy
Biomass
Biofuels
Cellulose
Organic
Photosynthesis
Flammable
Anaerobic
Bacteria
What is Bioenergy?
• Bioenergy is renewable energy made
available from materials derived from
biological sources.
• In other words - Bioenergy is energy stored
in materials made with the help of living
things.
Biomass
• Plants use photosynthesis to convert the
Sun’s energy into a form of chemical
energy called cellulose (a type of sugar).
• When plant matter or agricultural waste is
used as a fuel it is called biomass.
• The most common form is burning wood
Biomass to Biofuels
•Biomass can
be converted
into forms that
are easier to
use for
transportation
fuel needs,
called
biofuels.
Energy Transformations
How do we turn biomass into electricity?
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chemical potential energy (biomass cellulose)
thermal energy (burning biomass)
kinetic energy (steam)
kinetic energy (spinning turbine)
electrical energy
Canadian and Norwegian Bioenergy
• Bioenergy currently accounts for
approximately 15% of the World’s total
energy consumption.
• Bioenergy currently accounts for
approximately 6% of Canada’s total energy
supply.
• Bioenergy also accounts for approximately
6% of Norway’s total energy consumption
Ethanol
• Ethanol is produced by feeding biomass into
large heated tanks called digesters. Inside the
tanks, yeast converts the biomass into alcohol.
• the ethanol can then either be blended with
gasoline, or burned directly
– conventional engines can run on up to 10% ethanol
– special models can run on up to 85% ethanol
• http://dsc.discovery.com/tv-shows/othershows/videos/how-stuff-works-ethanol.htm
Biogas
• Most mammals, humans included, produce a
flammable gas called “biogas” as they digest
their food. Bacteria living in their digestive
systems produce methane as they break
down cellulose present in the food.
• Biogas is also produced in bogs and wetlands where large amounts of rotting
vegetation may accumulate. This methane
is the same as the “natural gas”, commonly
burned in our home’s furnaces and
barbecues. Biogas can be used instead of
natural gas for heating and cooking.
• Where else might biogas be “naturally”
produced around human communities?
Biogas
• collected during the
decomposition of
organic waste.
• the main gas
produced during
decomposition is
methane
•the Cloverbar Landfill in northeast Edmonton
collects enough biogas to produce electricity for
4600 homes
Biomethane Production
http://www.wired.com/autopia/2009/01/oslos-buses-to/
Biogas Generators
• Humans have learned to duplicate the biogas production
process in large tanks called biogas generators.
• To start the process, shredded plant materials and animal
wastes are mixed with water in the biogas generator.
Many kinds of naturally occurring bacteria arrive with the
shredded plant material. The tank is then sealed so no air
can get in. We say the conditions are anaerobic.
• Within days, a special kind of bacteria in the tank will
begin to produce biogas. These bacteria are known as
“methanogenic”, because they produce methane, the
main ingredient in biogas. The biogas forms bubbles in
the mixture, and collects at the top of the tank. It is piped
to a large balloon-like bag where it is stored until needed.
Lets Design a Biogas Generator for
Your Backyard
Let’s Build a Biogas Generator
Evaluating Biomass
• An advantage of biomass is that some of the CO2
produced from combustion is absorbed by the next
generation of plants
•Sometimes called
a carbon-neutral
energy source
Biomass
PROS
• fuels are readily
available
• no complex technology
is required
• can be converted into
biofuels
• biofuels burn cleaner
than gasoline
• Less net CO2
produced
CONS
• not very energy efficient
• Increases pesticide use
• Ethanol is toxic and highly
flammable
• In colder climates, biodiesel
tends to lose viscosity.
• requires large areas of land
and irrigation to make
enough plant matter (food
vs. fuel)
Biodiesel
• Biodiesel is a non-toxic and biodegradable
fuel that is made from vegetable oils, waste
cooking oil, or animal fats.
• Biodiesel is produced through a process
which reacts the oil with an alcohol (usually
methanol, although ethanol can also be used)
and a catalyst (such as sodium hydroxide).
• The resulting chemical reaction produces
glycerine and biodiesel.
Let’s Make Biodiesel!