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I'm Mich Hein.

I'm the managing partner of Nidus Partners in St. Louis, Missouri.

And I'd like to talk to you today about renewable natural gas.

Renewable natural gas, or any natural gas, is made predominantly from methane.

It's approximately 98% of natural gas.

There are other components including higher molecular weight carbons.

Or higher molecular weight hydrocarbons.

Greenhouse gas component of natural gas is actually quite high.

It's about 20x more potent than carbon dioxide.

The natural gas that I'd like to talk you today is a natural product

from the Archaea which are a group

of organisms that are different from bacteria.

People thought they were bacteria for a very long time.

They look like bacteria, they're about the same size, they're about half a

micron in diameter, they're rod shaped, they're about five to six microns long.

And they live largely in oxygen free environments Around the, the planet.

The Methanogenic Archaea are the, currently the

only known methanogenic organisms on the planet.

So if you see an organism that's producing methane, it's likely an archaea.

They're single celled.

They have distinct molecular and biochemical

characteristics that make them different from bacteria.

They're actually in many ways more

similar to eukaryotes, in their biochemical composition.

They're generally extremophiles, which means

they live in fairly harsh environments.

Either really cold environments, really

hot environments, environments that lack oxygen,

which, in our world today, is considered to be extreme, although in

the ancient earth oxygen was a rarity and so these organisms

evolved in highly reducing environments which is where their current niches are.

There are about 50 or maybe even 60 species that are known today.

The archaea are not as well studied as most prokaryotes or as eukaryotes

but we're beginning to collect a number of full sequences of the archaea.

They have relatively small genomes so they're easy to sequence.

Some common areas where one finds archaea are near hot springs

or thermal vents at the bottom of the ocean where they

actually live at very high temperatures in the 200 degree Celsius

range at even as high as ten or, or 12 bars.

So they can live in high temperature and high pressure environments.

generally, they cannot function under aerobic conditions,

but I'll tell you today about an

organism that actually has the ability to

tolerate oxygen in an application that we're using.

biogas, as most of you may have have

heard about biogas, it's actually a, a natural product.

Its most common derivation or the one that people are the most

familiar with is actually from the guts of ruminants, basically cow gas.

Biogas from many sources though, including from the bottoms of

swamps, from rice paddies, from the guts of sheep even

the guts of humans and from thermal vents, biogas is

typically produced of about 50% carbon dioxide and 50% methane.

There are some other minor gaseous products such as hydrogen sulfide

in particular from decaying biologic matter, like crops or, or animal waste.

But strikingly, cows are responsible for a, a large fraction of the

greenhouse gas emissions from biogas that we see on the planet today.

A little bit less than 20% of the biogas that we see

in our atmosphere, actually comes from digestion of plant biomass in cow guts.

Unfortunately, despite the photograph that you see

here, there's really no economic way to capture

the gas from from cow guts that we might be able to use for economic purposes.

The environmental impact of biogas as actually fairly significant.

This is a pie chart that you can see here that shows what the, the sources of biogas

are and you can see the largest single source,

in green here, is the enteric fermentation process from cows.

There's also natural gas which leaks into the atmosphere, which is the second

largest source that we have, from leaky pipe lines, from leaky gas wells, and

actually from normal leakage out of the earth where there are gas caverns that

are trapped close enough to the surface that have fissures that allow leakage.

But we also see rice paddies as a fairly significant source.

Wastewater treatment is a fairly significant source, and

solid waste which we would consider to be

from say, say landfills.

If you look at an example here, which is in Sweden, which

is a country that actually uses biogas effectively in, in energy generation.

You can see what the life cycle emissions

are, in grams of carbon dioxide equivalents per

mega joule of fuel and you can see

that of course, petroleum and diesel are pretty high

contributors but if you can actually use bio

gas derived from liquid manure you actually can get

a, a carbon credit for using this because

you're actually displacing carbon that would come from natural

gas, but you're also bringing carbon dioxide out of the atmosphere from the

crops, that you're using to feed the animals, that produce the liquid manure.

Unfortunately, biogas is actually a pretty low energy fuel, because it only contains

50% methane and the other 50% is effectively non-combustable components.

50% of the volume of the gas

that you combust from biogas is actually noncombustible.

So there are two challenges there.

The first one is if you're storing gas, which we do in volumes,

you pay for whatever the volume of the gas is that you're storing.

So if you're paying for 10,000 liters, and

you're only storing 5000 liters of combustible gas, you've

essential wasted the, half the capital, because you're only

putting half of the, combustible gas in the container.

In addition, the actual, use of that gas when you combust it is less efficient

than if you're combusting just say methane over, or natural gas; because when you

burn you, you actually heat up all the gas and so you're actually heating a

gas that you're not actually going to use

for anything; which is the carbon dioxide component.

So you lose twice effectively if you want to use biogas as a fuel.

On the other hand if you can produce it fairly

cheaply from decaying vegetative matter, or you can capture it

from agricultural environments, or from waste water treatment plants, you're

still getting a benefit because it's a renewable source of methane.

So the in situ conversion of the

CO2 component of the biogas into a more useful form would

be valuable if you're capturing this biogas instead of

having CO2 being a waste component or an inert component.

It would be great if you could take the C02 component and either

strip it from the, from the biogas so that you're left with pure

methane or actually convert that C02 into additional methane so that every mole

of carbon that's in your system ends up being a mole of combustible gas.

And so these two strategies, one is basically stripping of carbon

dioxide from the biogas to make it into pure methane, or what

we say upgrading the CO2 by a process called methanation, which is

turning CO2 into methane, are the two processes that people are considering.

The stripping, there are many commercial

processes today that are used for stripping

CO2 from biogas, and for that matter, from what are called sour gas

wells, where the natural gas that comes out of the ground actually has

too high a composition of carbon dioxide for it to be considered natural gas.

There's technologies you can use to strip half

the biogas away so you're left with only methane.

Or, a more modern and evolving technology

is this methanation technology where one takes

the CO2 fraction and tries to upgrade it and convert it to methane which means

effectively removing the oxygens from the carbon

dioxide, reducing that carbon molecule and putting

four hydrogen bonds in place of the two oxygen double bonds on the carbon atom.

And you can do that by chemical means or by

a biological process, and that's where the Archea come in.

So, is this a viable economic, model

for producing renewable natural gas, this upgrading?

And the answer is in some political geographies it is.

And this is a, a map of part of Europe that you'll see here.

And each of the the green dots here represents a site

where there is an upgrading facility where this carbon dioxide is either

being stripped from the biogas or the carbon dioxide is being upgraded

to methane and there's an injection site into the natural gas grid.

So basically you're taking biologically produced methane

and you're injecting it into the grid.

How are we providing the energy to do this?

Well you say well that's great but you've gotta spend energy to

upgrade that biogas or the carbon dioxide component or that biogas into methane.

If the energy is produced from a fossil fuel you're actually loosing because

you gotta burn that fossil fuel in order to generate the energy, but if

you use a renewable source such as wind or a photovoltaic power, you're actually

using a renewable source of energy to

power this reduction of the carbon dioxide.

And these two graphs here just show you

two environments where this one in Germany, which

is actually a projection based on the amount

of wind power that's going to be generated in Germany.

And this one for Denmark, which is actually current, the current situation.

Where you see the red line is actually the demand of power that is available.

And in this case, the blue line is the amount of wind

offshore energy that's being produced, and the yellow line is the photovoltaic.

You can see here it's periodic over days.

Seems true here in Denmark where the red is the

demand curve, and the green is the wind power production.

So in any instance where you see the height of

the curve of either the yellow curve or the blue

curve is above the red curve it means you're producing

more energy than you're actually using that there's demand for.

And the argument that is being used

in these political geographies is you can take

these excess energy now and rather than

running it to ground you can actually store

that energy in renewable natural gas by

taking the carbon dioxide component of biogas and

converting it to methane and making effectively natural

gas that you can inject into the grid.

And you can burn it where you're not

producing enough renewable energy to meet your demand.

Now, this is a commercial activity that's only begun to be used now in Europe.

It has potential for many other political geographies,

but the Europeans are actually pioneering this effort.

And this is, the other side of this curve,

which is the natural gas curve, which just shows

in the UK or in Denmark what the gas

production sources are and I'll highlight just Denmark here.

And you can perhaps look at these, graphs at your leisure.

But you can see that the natural gas, which is this mustard colored

area here, is actually in decline and projected to decline over time in Denmark.

The natural gas grid is built with sufficient capacity to manage

this, this is the projected consumption line is, and so as

natural gas is being pumped out of the earth declines, the

question is, can you produce enough additional gas to meet demand?

And these two green curves are curves that are saying,

yes, we can do that by biogas and by biogas upgrading.

So this is a graphical representation of what the solution might

be to this problem that you saw on, on the previous slide.

And that is to take wind energy and when it's not needed

for, for demand, for running toasters and recharging automobiles.

By running your washing machine and your dryer

and your dishwasher, is you can take that

gas and you can store it and reuse

that gas either in gas-fired power plants or you

can put it back onto the gas grid where it can be used for transportation fuel, or

for for chemical synthesis or any of the

other demand uses for natural gas on the grid.

And the process by which we imagine that can be carried on today is electrolysis.

That is where the power that comes from the

wind and the solar energy produces hydrogen and oxygen.

And we use the hydrogen in a biochemical methanation process, which you see here.

So this is the means of

producing renew, renewable gas via biocatalytic methanation.

Again, you can do this chemically as well.

In our case, we have a biocatalyst, which is the archaea.

And we simply use an electolyzer that runs on the renewable

energy, we use the archaea to go through a methanation process.

You can see this is actually exothermic so we produce some heat which is a byproduct.

The net reaction also produces oxygen which can be sold or

can be actually used in some chemical processes or for oxy-combustion.

So we have three inputs.

Water, which you can get from the municipal grid.

Low cost re-stranded electricity from renewable resources.

And carbon dioxide from biogases, from fermentation, or from

any other, any other source where it's actually concentrated.

And the outputs are this pipeline-grade renewable gas, which is

now completely renewable from its carbon source and its energy.

Oxygen which can be used for industrial medical applications and heat

which actually can be used locally in many cases in these facilities.

So this Archea is a biological catalyst which is

being used for this and this is just a table

that shows you all of the characteristics of the

Archea and I would just point out two characteristics here.

One is that they're highly efficient in

that they don't capture much energy for themselves.

They give most of the energy back to us.

And the second one is that on the mass balance basis

they effectively take all the carbon monoxide that would give them and

turn it into a product for us which is the methane and

they use very little of the carbon for their own biomass production.

Those are how we, how we envision the archea would be used and this is just

a summary slide to show you that, if you can find carbon free energy and CO2, we

have a biological process that can make completely

renewable natural gas to put onto the grid

so that we don't need to pump as much, fossil carbon outta the, out of the Earth.

Thank you.

Biogas Part 1

Our Energy Future

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