Hi there. My name is Alexis Wolfe, and with my partner Shannon Zaret and the rest of the BioenergizeME Team, we would like to thank you for joining us to learn more about the basics of biomass and bioenergy.
The purpose of this webinar is to provide general background about bioenergy, its creation, and its potential uses.
We will go through some of the definitions involved in bioenergy and take you through the types of feedstocks that are used for bioenergy, and the basic products that are made up of biomass.
Then we will take you step by step through the biomass to biofuels life cycle, and show you what it exactly takes to turn recently living plant matter into an energy product.
We will then highlight the important aspects of bioenergy and the context of bioenergy within our current U.S. energy landscape.
Finally, we will discuss why the U.S. Department of Energy is emphasizing research and development into this important technology.
If you have any questions or would like to know more about the basics of biomass or bioenergy, please feel free to reach out to the Operation BioenergizeME Team at the email listed on the screen.
BioenergizeME@ee.doe.gov
If you're looking for more resources on bioenergy or biomass, please visit the education and workforce development website at the link provided on the screen.
energy.gov/eere/bioenergy/education-and-workforce-development
You can find this webinar as well as other Operation BioenergizeME webinar recordings and slides at the Bioenergy Technologies Office website listed on the screen.
So, lets jump right in and talk about biomass and bioenergy.
Biomass is the organic material that has stored sunlight in the form of chemical energy.
Plants can be thought of as warehouses for solar energy.
Through photosynthesis, plants collect sunlight, carbon dioxide, and water, and convert it into chemical energy in the form of sugars that are stored in their biomass.
One type of sugar that is created by biomass is called cellulose, which we will talk about in a little bit.
Bioenergy is a form of renewable energy derived from biomass to generate heat and electricity, also known as biopower; biofuels, which are transportation fuels; biochemical; and other energy related bioproducts that are produced from biomass.
Bioenergy is energy that is produced from renewable biomass resources.
However, bioenergy does not include solar, wind, water, geothermal, or nuclear energy.
Bioenergy also does not include non-renewable fossil energy resources like coal, oil, or natural gas.
Biomass that is used for bioenergy production is called a feedstock.
There are many different types of feedstocks that can be utilized for bioenergy.
For example, the biofuel ethanol, which is made from corn, represents the first generation of biofuels.
The Department of Energy is focusing on new technologies to make biofuels and bioenergy from many non-food sources
such as corn cobs and stocks, also called corn stover, woody bioproducts, municipal waste, and algae.
Ethanol that is produced from cellulose, and non-food sources, is called cellulosic ethanol.
Cellulosic ethanol and bioenergy made from non-food sources are part of the next generation of bioenergy.
The five different types of sustainable feedstocks that are primarily used for next generation bioenergy production include:
Agricultural residues, forest residues, energy crops, algae, and municipal solid waste.
Agricultural residues are plant parts left in the field after harvest.
This plant matter and secondary residues like manure and food processing waste can be useful feedstocks.
Agricultural residues are plant parts left in the field after harvest, which we already talked about...
Forest residues are leftover wood or plant material from logging operations, forestry management, and land clearing.
Secondary residues like mill wastes supplement this category.
As well, energy crops are fast growing trees and perennial grasses that are specifically grown for energy uses.
Trees and perennial grasses can often be grown on land that is less suitable for conventional crops, and can stabilize the soil.
Municipal solid waste, such as dead leaves, food scraps, and other garbage thrown out, has the potential to also be a bioenergy feedstock.
And last but not least, many macroalgae, microalgae, or tiny algae, and cyanobacteria, or blue-green algae, carry out photosynthesis to drive rapid biomass growth.
Algae biomass can contain really high levels of oil, making it a promising feedstock for biofuels, including renewable gasoline.
Okay, so lets take you back to Biology 101
Probably one of the very first sections
if you guys are familiar with, where you covered macromolecules.
So, essentially what were trying to get at in the biomass are these high value macromolecules.
Specifically carbohydrates and lipids, and what is really important about these macromolecules is the bonds between them hold tremendous energy potential.
So when we talk about plant material
we are talking about different carbohydrates which vary from simple sugars
all the way to your larger polysaccharides
that contain long chains of individual sugar units bonded together.
So, your starches and your cellulose.
So right now, the current ethanol that is on the market is mostly made out of these simple sugars.
Lipid are another class of macromolecule, those are your oils and your fats.
Those are a little bit more energy dense,
so they can be used for biodiesel,
for larger trucks and vehicles.
Proteins are another class that are incredibly important to us.
they can actually be converted into biobased products, separate from transportation fuel.
Enzymes, which are a class of protein, are actually very useful to the process of obtaining carbohydrates
and lipids because they can help us catalyze reactions and breakdown these larger
polysaccharides and larger fat molecules
So, we'll talk about one macromolecule in particular
thats of great interest to the bioenergy industry, and that's cellulose.
It is the most abundant organic terrestrial polymer on the planet
and it is the main component of plant cell walls.
Essentially it is made from individual glucose sugar molecules
and you can really think of cellulose as the steel beams of the plant cell walls,
really holding it together.
This is an incredibly powerful macromolecule
and one of the most important macromolecules that were trying to access and break down into individual sugar units
and we'll talk about what does that exactly mean, what are we meaning when we try to get at the sugar units.
So lets look at the life cycle.
So very simply, how are we turning biomass into bioenergy?
So we start at the feedstock, the raw material,
we transport that raw material to a biorefinery
where it is converted into a high value fuel product.
And then we can take that product, distribute it, until it finally gets to the end user, you, so you can use it in your vehicles.
So, the first part of the process, feedstock supply and transport.
So here we have renewable biomass that is harvested
basically breaking it down into smaller pieces so it is easier to carry
rolling it into bales, and then we process that biomass,
transporting it to a storage site or a eventually a biorefinery.
Okay, so here is an example of a potential feedstock to a biorefinery pathway
So when you are looking at this, it is important to note that bioenergy only uses purpose grown woody crops
and that we are showing trees here
These are woody residues that can not be used to make lumber
or other wood based products.
Such as, forest thinning, tree limbs, and treetops.
So they are really an underutilized resource at this point
They are not being utilized.
So, picture this, I own and manage some land in Virginia where I grow oak trees
these are used to make lumber, as well as fast-growing dedicated woody biomass, poplar and southern pine
I can contract a logging company to come in and cut down the trees and take the wood to make lumber.
However, there is a lot that is still left over in the process of collecting the lumber
theres a lot of tree branches and limbs, stumps, and the tree tops
that right now have no use
So thats where bioenergy can come in
I can harvest and process those leftover parts of the trees, as well as the dedicated woody trees that I grow
such as what is shown on this slide.
Seen here, standing popular and southern pine trees are felled by machines, then placed in a pile in a process called yarding
The piled trees, as well as the leftover tree limbs, stumps, and tree tops are then delimbed and debarked with a grappling machine,
and then broken down into small pieces by passing through the chipper.
These smaller chipped pieces allow for easier transport to the biorefineries.
After the chipped woody biomass arrives at the biorefinery, it is stored until it is ready to process.
The biomass is dried in larger dryers so that it can be converted into fuels and products.
This preprocessing step is very important, you want to get it broken down into smaller easy to use particles.
Okay, this is a very simplistic look at what goes on in a biorefinery.
and were going to get into it a little deeper in a minute.
So essentially we have the biomass that has been preprocessed, it is easier to work with, it is in smaller components.
And essentially we want to treat that with chemicals
we call this a pretreatment step, either with extreme heat,
acid or salt solution.
We want to get something in there that can break up the cell wall structure.
So that's the first step, we want to break apart the cell wall structure, its really tough.
Then, enzymes break down cellulose into individual sugar units
Then, microbes can ferment that sugar into ethanol,
And then the ethanol undergoes distillation, is purified, and prepared for distribution.
So this is a standard celluosic biorefinery,
but as you can see in a couple more slides, we actually have some additionally ways to convert biomass into finished fuel products.
Okay, so breaking it down we actually have two pathways.
It can get a little more confusing but for simplicity sake
its easier to say we break down biomass in either one of two ways.
With extreme heat and pressure,
or with biological organisms and chemical catalysts
Okay, so we can think of it as thermochemical versus biochemical
Now, the way that we have described this
is low temperature conversion versus high temperature conversion.
So essentially low temperature conversion follows a very similar pathway to what I described before
So the biomass undergoes what is called a pretreatment step.
As you can see from the slide, what we want to do is break the tough structure of a plant cell wall
So the plant cell wall
is a combination of lignin,
which is not a polysaccharide, its a very complex molecule in and of itself.
hemicellulose, which is a polysaccharide,
and cellulose another polysaccharide.
And they are all entangled together in this really tough knot
And what we really need to do is break apart that knot
So we essentially treat some plant material
either using heat, acid, or liquid salt solution.
We want to break those up and make all of those larger longer molecules,
specifically the polysaccarides, more accessible.
Okay, so you can see in the slide that we are breaking it apart
were trying to break all these little pieces apart, so its nice and untangled.
Then we can take the polysaccarides
the cellulose, and we want to get at the individual sugar units
So we use enzymes, that special class of protein,
and those enzymes split those large molecules into smaller sugar sub-units,
easier for us to work with the sugar that way.
One enzyme we use in particular is cellulase.
It cleaves those tight bonds, and now you're left with sugar.
So then, there are a variety of microbes that can actually ferment sugar
so basically they consume the sugar, and as byproduct of their metabolism,
as a byproduct of them consuming it,
they produce what we call ethanol.
We can also engineer microbes to produce
renewable hydrocarbon fuels, these are fuels that are
chemically equivalent to gasoline, diesel, and jet fuel.
So the microbes ferment that sugar either into ethanol,
and we'll talk about exactly what ethanol is in a little bit
or, renewable gasoline, diesel, and jet fuel,
our finished fuel product.
Then we have the high temperature conversion.
Okay, so basically we have our pretreated biomass
we've got smaller pellets of it
So essential there are three different process for various different reasons.
Pyrolysis, gasification, and hydrothermal liquefaction
All three of these processes use extreme heat and pressure,
to basically break down the biomass either into a gaseous or liquid byproduct or intermediate.
Hydrothermal liquefaction is generally best used for wet feedstocks
so when we talk about algae, were usually talking about hydrothermal liquefaction.
Heat and pressure in the presence of water as well.
Pyrolysis typically yields a bio-oil.
So we heat that to a certain extent and then we let the gas
basically condense down into a bio-oil.
In gasification, obviously the gaseous intermediate, we call that a syngas.
So you either have a bio-oil, or a synthesis gas as your intermediate.
Then, unfortunately those intermediates are not ready for the gas pump.
They still have a lot of chemicals in the mixture that have to come out.
Its not quite compatible yet.
So what we can do, the intermediates undergo an upgrading step,
probably several upgrading steps using different chemicals.
And essentially what we are trying to do is remove all of the unwanted materials
and basically build, chemically build, a very strong molecule
that we will be able to put in our gas tanks easily
and that will be compatible with existing infrastructure.
So, deconstruct the biomass into a gas or liquid intermediate,
and then chemically upgrade it into a finished fuel product that is compatible with existing infrastructure.
Lastly, once the product is finished
and once we've got it to a point that it will work well and easily with current infrastructure
we then distribute it to its final end use,
which could either be, like we have said, aviation, heavy trucks, diesel, light engines, and then of course gasoline
So your standard cars on the road.
So we have talked a lot about bioenergy making advanced biofuels,
But it is important to know that bioenergy can make things other than fuels as well
such as electricity, which is also call biopower,
Bioproducts, which include plastics, cleaning agents, chemicals, food additives, nutraceuticals,
things that go in your cosmetics,
pretty much anything that plant material can be made out of.
As well as creating heat and steam that can be used in our homes.
So we first wanted to talk about what are some of the type of vehicles that you can actually put biofuels in.
We can put them in busess, larger trucks,
personal vehicles, large construction vehicles,
boats, planes, and regular trucks.
Biofuels are the end product when biomass is converted directly into a liquid fuel
The most common types of biofuels used today are ethanol and biodiesel
Ethanol is an alcohol that is made by fermenting the sugar components of biomass.
Similar to the process that we talked about before
Ethanol is now actually used as a fuel additive for cars at a 10% blend,
further reducing the need for oil imports.
It is also blended in gasoline as an oxygenate to increase octane and improve vehicle emissions.
Another type of ethanol used today is E85,
which is a 85% ethanol blend with regular petroleum, so 15% petroleum blend
that can only be used in a vehicle called a flexible fuel vehicle.
and these flexible fuel vehicle are designed to tolerate
the fuel's high ethanol content and standard gasoline interchangeably,
so you can put E85 in your gas tank with a flex-fuel vehicle,
or you can put regular gasoline in your gas tank.
Another type of biofuel that we can create is renewable hydrocarbon fuel.
So renewable hydrocarbon fuels are compounds that are composed primarily containing hydrogen and carbon atoms.
Examples of renewable hydrocarbon fuels include renewable gasoline, jet fuels, and diesel fuels.
So when we talk about renewable gasoline,
or renewable hydrocarbon fuels,
we are talking about "drop-in" fuels
Which means they are compatible with existing cars, trucks, jets, and infrastructure that we already have,
and can serve as a direct replacement for petroleum-derived gasoline, jet fuels, and diesel fuels.
So we would not have to change all of the cars that are out on the roads today, with a drop-in fuel
The last one I wanted to talk about was biodiesel.
Biodiesel is a mixture of fatty acid, made from vegetable oils, animal fats, recycled greases, and even algae.
Biodiesel can be used as a fuel for vehicles in its pure form,
but it is usually used as a petroleum diesel additive to reduce levels of
particulates, or little particles in the air, such as sulfates,
as well as carbon monoxide, hydrocarbons, and air toxics that are usually emitted from diesel-powered vehicles.
Renewable diesel is a really good alternative to petroleum-based diesel.
It is chemically similar to what you would already get from a diesel pump,
but it releases the lowest emissions out of all the diesel blends that are out there.
So moving on to products that are made from biomass,
Today, conventionally, petroleum is refined to make chemical feedstocks used in thousands of products that we use everyday.
Many of these feedstocks that are made from petroleum could actually be replaced with value-added chemicals produced from biomass
to manufacture clothing, plastics, lubricants, and other products.
For example, you may have seen plastic bottles that have a plant symbol on them.
That means they have been made from a biomass source.
The emerging U.S. biobased products industry
combines expertise and technology from the agriculture, forest products, and chemical industries
to create these new plastics, chemicals, and composite materials from renewable resources.
They often require less energy to produce,
and produce fewer greenhouse gas emissions than petroleum-based equivalents.
So, another added bonus to bioproducts
is that they add value to biofuel production
improving economics of biorefinery operations
and making those biofuels more cost-competitive
or cheaper for the consumer, and cheaper for producers to make.
So we also wanted to briefly touch on biopower,
which is where biomass is converted into heat and electricity
using processes similar to those used with fossil fuels
So, one of the key attributes of biomass
is that it can be available upon demand.
The energy is stored within the biomass until it is needed.
whereas, other forms of renewable energy
are dependent on variable environmental conditions,
such as wind power being dependent on wind speed,
and solar power being dependent on sunlight intensity.
Until several decades ago in the United States,
biomass was actually primarily used to provide heat for cooking and comfort.
Technologies that can generate electricity from the energy in biomass fuels have since been developed.
The scale is actually small enough to be used on a farm or in a remote village,
and it can also be scaled up large enough to provide power for a large city.
Okay, now that we have gone into the different end-use, end users for biomass,
lets look at where we currently are with bioenergy in the United States.
So, all things need energy,
every sector need energy, and there are two general ways to classify energy
So, there are renewable sources,
that is an energy source that can be easily replenished by the environment on a relatively short time scale,
And then you have non-renewable sources,
that is an energy source that can not be easily recreated, especially on a human time scale.
So if we take a little look,
at the current energy consumption by source,
and even though this is from 2014, it still provides you a good snapshot
of where the industry is right now
so renewable energy accounts for 10% of the total,
and non-renewable of course is the rest
but what is interesting about the renewable energy sector,
is that 50% of that renewable energy is supplied by biomass resouces
so they make a significant part of the total.
Okay, so why are we talking about bioenergy?
Why right now?
This goes into a larger topic of energy literacy,
and we have other webinars which address that,
but the way we use bioenergy has changed dramatically over time.
We have really developed quite a few sophisticated methods,
to harness those macromolecules in biomass.
And, bioenergy is a crucial part of America's All of the Above Strategy.
Its an important component that we are looking to to meet America's energy needs.
So its one of the very many renewable energy resources
but it is quiet unique, and I'll talk about that in a second.
It is a little bit unique compared to wind or solar.
So it is important for people to understand basic energy principals.
Differences in energy resources and the different technologies options available,
specifically the benefits and challenge of various energy resources.
So if you look at something like bioenergy,
what is unique about, it is that it is possibly the only energy resource that could offer a viable substitute
for petroleum based liquid fuels,
at least in the near term.
Especially when you are looking at industries like aviation, or ships,
these larger vehicle where electrification would be a lot more challenging.
You can see that bioenergy can play a very significant role
and be very useful for those types of industries.
Understanding each energy resource and the benefits of each is very important.
For students and their peers to be able to understand
that they can play an important role in shaping America's energy future as well.
So, now on to the biobenefits, we have talked a lot about
different resources, how they are converted into end-use products,
where we are, a snapshot of bioenergy in the U.S.
So lets talk about the benefits of bioenergy
So, if we look at an economic, social, and enviromental standpoint as an example
We saw how many end-use markets,
we have power, products, fuels,
and these will no doubt open doors for a variety of different industries.
creating jobs, rural development, and workforce training.
In addition to that, having a domestic resource
will help with energy security, lower imports of petroleum.
And lastly, environmental sustainability,
so bioenergy can be cultivated sustainably,
and there are actually a number of feedstocks that can maintain if not improve environmental services.
So for example, certain energy crops can actually help reduce
nutrient run-off, they can help store soil carbon,
they can even provide habitat for a variety of wildlife.
So there is a number of benefits that are associated with the use of bioenergy,
and leaders are helping to determine how we can plan
for the industry to expand in a way that meets these three pillars of sustainability
Okay, so the idea of the bioeconomy is one in which
we have a sector of the U.S. economy that relies on biobased products.
In general this slide is a good depiction of the potential of the bioeconomy.
So if we look we have the potential to create 1.1 million direct jobs.
Its about $250 billion in the U.S.
85 billion kilowatts of electricity to power 6 million households,
1050 trillion BTUs of thermal energy,
50 billion gallons of biofuels,
displacing almost 25% of all transportation fuels,
50 billion lbs of biobased chemicals and bioproducts,
replacing a significant portion of the chemical market,
and 400 million tons of carbon dioxide equivalent reductions every year.
So this is the potential for biomass in the United States.
And with that, thats a wrap!
So thank you so much for joining us today
for our Biomass Basics webinar.
If you want to test your knowledge of biomass and bioenergy that you learned today
check out our Bioenergy 101 quiz which can be played in the classroom
and is a really fun game to use.
If you are curious to learn more about bioenergy,
please visit the Bioenergy Technologies Office website,
or the bioenergy education and workforce development site.
And, as always, email the BioenergizeME team
if you have any questions or want to know more
about education and workforce development activities in bioenergy.
We'll see you next time!
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