Algae Carbon Capture: Make Your Own Algae Tank & Absorb CO2

[CCatalyst]

I've noticed a lot of interesting replies, but I also want to point out a few ideas as well.

Can't we use algae in tandem with other renewables like solar and wind? Put it like this, are there solar panels out there that can absorb only green light and allow the rest of the light to pass through? Because here is my idea. We would use the solar energy to run the air pumps to provide the carbon dioxide from the atmosphere and the compression sequence. Also, this provides additional power for charging a lithium battery. When the sun goes down, the battery powers all of these processes as well as a grow-light that gives off red and blue light to keep the photosynthesis going even after the sun goes down.

Could that help? Let me know and keep me informed.

 

[Ivan Seeking]

I've noticed a lot of interesting replies, but I also want to point out a few ideas as well.

Can't we use algae in tandem with other renewables like solar and wind? Put it like this, are there solar panels out there that can absorb only green light and allow the rest of the light to pass through? Because here is my idea. We would use the solar energy to run the air pumps to provide the carbon dioxide from the atmosphere and the compression sequence. Also, this provides additional power for charging a lithium battery. When the sun goes down, the battery powers all of these processes as well as a grow-light that gives off red and blue light to keep the photosynthesis going even after the sun goes down.

Could that help? Let me know and keep me informed.

It certainly appears to make sense to power some low-load electrical devices using solar power. Why go from sun to algae to fuel to generator to electricity, when we can go sun to cell to electricity? However it is important to remember that a solar cell comes with a carbon footprint. So one needs to think carefully about the energy that went into producing and distributing any hardware used. And how long will that hardware last. This must be factored into the efficiency of the farm.

As for running lights powered by stored energy, think about the efficiency. We go sun, to solar cell, to battery, to light, to algae. The efficiencies go as approximately 25% for the solar cell, let's say 80% for the battery, and assume LED lighting at 90%. That brings the efficiency of producing the light down to 18%. And in all likelihood, the algae won't be as productive using artificial lighting because LEDs don't produce full-spectrum light. Now factor in the carbon footprint for the hardware and estimate the life expectancy of each component. Batteries don't last long so I would bet the carbon footprint for the batteries kills any advantage.

You also have to factor in cost. What does it cost to purchase and install the hardware to provide artificial lighting? How long will that equipment last? Now add that amortized cost to the cost of producing fuel and you likely lose the competitive advantage at the pump.

It is very easy to start unintentionally hiding costs and carbon emissions when you introduce additional hardware.

Speaking of hidden costs, another big reason for ocean farming is to avoid land taxes! Taxes on the land could be a significant or even a game-ending cost.

 

[Rive]

We go sun, to solar cell, to battery, to light, to algae. The efficiencies go as approximately 25% for the solar cell, let's say 80% for the battery, and assume LED lighting at 90%. That brings the efficiency of producing the light down to 18%. And in all likelihood, the algae won't be as productive using artificial lighting because LEDs don't produce full-spectrum light.

That's actually a boost. I don't know specifically about algae, but most plants does not really need yellow. So if you leave that out then you can spare a good deal of energy.

Battery kills the deal, that's for sure. But in food production just solar panels and LEDs can make a decent work. One problem with winter is not just temperature, but the length of the day (as the length of the time with sufficient light) and the intensity of light too. With adding artificial boost (at morning and twilight just as long as PV can still sustain this) and in periods with clouds it can keep your greenhouse ticking.

Of course, regarding energy balance it's a complete disaster. But fresh vegetables sells good at winter.

 

[CCatalyst]

It certainly appears to make sense to power some low-load electrical devices using solar power. Why go from sun to algae to fuel to generator to electricity, when we can go sun to cell to electricity? However it is important to remember that a solar cell comes with a carbon footprint. So one needs to think carefully about the energy that went into producing and distributing any hardware used. And how long will that hardware last. This must be factored into the efficiency of the farm.

As for running lights powered by stored energy, think about the efficiency. We go sun, to solar cell, to battery, to light, to algae. The efficiencies go as approximately 25% for the solar cell, let's say 80% for the battery, and assume LED lighting at 90%. That brings the efficiency of producing the light down to 18%. And in all likelihood, the algae won't be as productive using artificial lighting because LEDs don't produce full-spectrum light. Now factor in the carbon footprint for the hardware and estimate the life expectancy of each component. Batteries don't last long so I would bet the carbon footprint for the batteries kills any advantage.

Keep in mind the solar panels above the algae only absorb the green light during the day. The blue-red grow lights, which do not cover the entire spectrum, only run at night. This way we have both day and night coverage. Plus aren't lithium batteries the best we have at service life and storage?

Also, can I buy a sterling engine that can run on any fuel? Like vegetable oil from the algae?

 

[Ivan Seeking]

Also, can I buy a sterling engine that can run on any fuel? Like vegetable oil from the algae?

I would think any fuel requirement for demo devices would be fairly specific

 

[Ivan Seeking]

Here is an important calculation to consider. Someone please check my math. Let's assume that we have an algae farm that produces 4000 gallons of fuel per acre-year at 50% efficiency. That means we need 2000 gallons of fuel to power the farm for each acre of algae, per year.

Biodiesel has about 119,000 BTUs of energy per gallon. That comes out to about 126 megajoules per gallon. At 2000 gallons per acre per year for power, we get about 252,000 megajoules per acre-year. With 31,557,600 seconds per year, we have 252,000 megajoules per 31.5 megaseconds, which gives us a constant power supply of about 8000 watts per acre.

We have 43,560 square feet per acre. So that means we can use no more than 0.184 watts per square foot to run the farm.

Running the farm includes the growth and processing of the algae, and the energy needed to convert oil to biodiesel, or to make ethanol. It also includes the energy losses in the diesel engines and generators, where at best we can hope for around 35% efficiency. In other words, we really only get 35% of those 2000 gallons in electrical energy used to run the farm.

 

[Ivan Seeking]

On the up side, we are using that "lost" 65% of those 2000 gallons to "generate" nitrogen fertilizer, for air purification, to produce pure water, CO₂ to accelerate growth, and a percentage of the pressure and volume of gases needed for aeration (which also helps to provide agitation).

 

[Rive]

...we can use no more than 0.184 watts per square foot to run the farm.

I did not check it in details, but sounds about right, on par with other plant-based industries. You dropped the plowing but got the circulation and such.

That's why I think that this kind business should not be about having high energy yield (and especially not about having electricity). It should be about having fuel (chemical energy) in usable form (definitely not freely interchangeable with electricity), and having 'side products' as food or feed (well, these may be the primary product, actually).

On side note, by my opinion those existing 'energy plantations' are in the same trap. Energy harvesting should be done integrated with the other agricultural activity, and not as main business. That just makes them dependent on government donations.

If somebody wants to 'save the planet' then please do and propagate an integrated system for agriculture. Otherwise - please just plant trees.

 

[Ivan Seeking]

That's why I think that this kind business should not be about having high energy yield (and especially not about having electricity). It should be about having fuel (chemical energy) in usable form (definitely not freely interchangeable with electricity), and having 'side products' as food or feed (well, these may be the primary product, actually).

Solar cell technology has made so much progress that it makes more and more sense to use solar to help power a fuel farm. And you are right! The point is to store energy in the form of fuel, not to produce electricity. And the practicality of solar cell power is literally changing year by year. The advances there have been on par with the history of the transistor.

However, in order to produce fuel from algae, you really need a source of CO₂. If the carbon comes from an algae fuel, then the farm is carbon neutral in that regard. But if you simply mask carbon emissions from a factory or similar by using them to grow algae for fuel, then the farm is NOT carbon neutral. It would make more sense environmentally to sequester the carbon. However growing algae for fuel is not practical without a concentrated source of CO₂. You likely can't grow the algae fast enough to be profitable.

By producing your own power onsite using fuel from algae, you not only power the farm, you also have the needed source of carbon neutral CO₂.

There is also the issue of nitrogen fertilizer. I don't know if you can solve that problem without the diesel engines. That solution is pure elegance.

Oh yes, and as for your comments about a farm serving multiple purposes, there is nothing that can multitask like algae! That is part of what makes it such a great fuel option.

As they say in the Exxon algae commercial, "You wouldn't believe the potential it shows". That's the truth!

 

[Rive]

if you simply mask carbon emissions from a factory or similar by using them to grow algae for fuel, then the farm is NOT carbon neutral.

Well, I don't think so. Regarding the algae farm itself, as long as the energy balance of the farm is covered while the CO2 balance is in the negative, it's production is carbon neutral.
It does not matter where and how the loop is closed (don't have to know where the fuel is used, the food is eaten). Just concentrate only on the farm.

There are lot off gimmicks around the CO2 and green quota business so some skepticism is absolutely right, though.

By producing your own power onsite using fuel from algae, you not only power the farm, you also have the needed source of carbon neutral CO2.

Well, that's not so simple. You can make a loop within the local carbon usage, but that won't cover the output of the loop. That should come from somewhere (concentrated) too.

Nitrogen is OK, though, since it comes from the air (used in the diesel). But if you have food/feed as output, you need to cover the nutrients of those as input.

there is nothing that can multitask like algae!

Well, since it's a single cell organism it has to store fat and sugar locally. But I think there are advantages in specialized plant tissues too. Crop does need far less processing than algae...

I believe once the GMO hysteria passed genetic engineering will has a lot to say in this business.
But till that, having a 'GMO-free' sticker on some fuel stations would bound to happen

 

[Ivan Seeking]

Well, I don't think so. Regarding the algae farm itself, as long as the energy balance of the farm is covered while the CO2 balance is in the negative, it's production is carbon neutral.
It does not matter where and how the loop is closed (don't have to know where the fuel is used, the food is eaten). Just concentrate only on the farm.

There are lot off gimmicks around the CO2 and green quota business so some skepticism is absolutely right, though.

There is a lot of work focused on using carbon twice. The idea is to use the emissions from factories to accelerate algae growth for fuel. And while that does reduce the overall use, it doesn't eliminate the carbon from the factory. That just passes through the algae and fuel and eventually into the atmosphere.

Well, that's not so simple. You can make a loop within the local carbon usage, but that won't cover the output of the loop. That should come from somewhere (concentrated) too.

You can only output as much carbon as you input. The fuel doesn't magically release carbon by burning it. It can only release carbon the algae absorbed. As long as no fossil fuels were used to supply the carbon for algae growth, as long as that carbon was already in the ecosystem of the planet, then we are not adding any new carbon to the atmosphere.

Nitrogen is OK, though, since it comes from the air (used in the diesel).

The nitrogen comes from the air. But the diesel engines do a great deal of work to produce the oxides of nitrogen. However we have already accounted for that energy loss so we don't pay twice. Also, nitrogen fertilizer comes with a relatively large carbon footprint

For nitrogen-based fertilizers, the largest product group, the process starts by mixing nitrogen from the air with hydrogen from natural gas at high temperature and pressure to create ammonia. Approximately 60% of the natural gas is used as raw material, with the remainder employed to power the synthesis process.

https://www.fertilizerseurope.com/fertilizers-in-europe/how-fertilizers-are-made/

But if you have food/feed as output, you need to cover the nutrients of those as input.

The sun does that for us along with the carbon, nitrogen, oxygen, and hydrogen.

 

[CCatalyst]

Well people keep saying we have trouble if we scale it up. But what if we DON'T scale it up? Would it be more efficient then? After all, this is a DIY forum. SO does anyone have any ideas about that tank to use, how often I should circulate air through it, how I extract the oil through algae, and most importantly what type of algae I should use?

 

[Rive]

Well people keep saying we have trouble if we scale it up. But what if we DON'T scale it up?

As a DIY project, you can (will) just neglect plenty of cost items and requirements while it is already satisfying to produce some lamp oil or some sushi nori (honestly, I don't know what kind of food-like stuff an algae enthusiast would prefer).

If you scale this up, it'll (it should!) produce quality assured standardized product and it is expected to be profitable, with a positive energy (negative carbon) balance. Quite an engineering project. A garden pool with some plastic foil won't suffice.

Consequently, as DIY it's unlikely to have negative carbon footprint: not without the required kind of in-depth engineering. It'll nothing to do with saving the planet.

 

[Ivan Seeking]

Well people keep saying we have trouble if we scale it up. But what if we DON'T scale it up? Would it be more efficient then? After all, this is a DIY forum. SO does anyone have any ideas about that tank to use, how often I should circulate air through it, how I extract the oil through algae, and most importantly what type of algae I should use?

Just the opposite, based on my two years of research and a team of highly qualified experts, it is impossible to do this at small scale with a negative carbon footprint. Success depends on the economy of scale. And this isn't for amateurs. It is highly complex. You will just end up with a big stinky mess.

 

[Ivan Seeking]

You might start researching the market to see who is actively developing biofuels. Try to get a job or internship with one of those companies. Start studying. Figure out how to contribute in a practical way. Here are a couple of companies that are active

https://www.algenol.com/sustainable-products/?category=ndustrials
http://solazymeindustrials.com/

See also
https://en.wikipedia.org/wiki/List_of_algal_fuel_producers

 

[Rive]

And this isn't for amateurs. It is highly complex. You will just end up with a big stinky mess.

I've been wondering how can an amateur identify the algae. If you grow - for example - carrots, that's simple. You have either carrots or something else. But for algae, all you get is a green goo. How do people (youtubers, to be precise) determine which (composition of) algae is that?
Or it's just the usual hope/ignorance mix?

 

[BillTre]

You can buy pure strains from aquaculture suppliers, or maybe get them from researchers.
Good technique is required to maintain the purity.

If you want to start from something you have, you could try making pure strains from the presumed mix you have now.
Making a clone from a single cell would be one way.
Identifying what you have would probably require a microscope, maybe some dyes.

 

[Ivan Seeking]

You can buy pure strains from aquaculture suppliers, or maybe get them from researchers.
Good technique is required to maintain the purity.

If you want to start from something you have, you could try making pure strains from the presumed mix you have now.
Making a clone from a single cell would be one way.
Identifying what you have would probably require a microscope, maybe some dyes.

UTEX [University of Texas at Austin] is a major supplier of pure algae cultures. That was where I purchased my cultures
https://utex.org/

Maintaining a pure strain is one of the biggest challenges. You can have the DNA tested. But there are other methods. There are over 30,000 identified species of algae. This is one of the challenges for the fuel industry - which one do you use? Even a major supplier like UTEX only has a handful of species.
https://utex.org/collections/living-algal-strains?sort_by=relevency&page_num=2

 

[Ivan Seeking]

Botryococcus Braunii is considered to be the beginner's strain. It can allegedly produce yields of oil up to 75% by weight.

 

[BillTre]

How do you harvest the oil, from mashing up the cells?

 

[Ivan Seeking]

How do you harvest the oil, from mashing up the cells?

The early efforts involved using an olive press. That is one of the tools you need to produce fuel at $50 a gallon. Far more advanced techniques are used now ranging from the use of solvents, to ultrasound, to supercritical extraction methods. Economically and efficiently removing the oil from the algae is one of the ongoing challenges for reducing processing costs.

 

[CCatalyst]

The early efforts involved using an olive press. That is one of the tools you need to produce fuel at $50 a gallon. Far more advanced techniques are used now ranging from the use of solvents, to ultrasound, to supercritical extraction methods. Economically and efficiently removing the oil from the algae is one of the ongoing challenges for reducing processing costs.

So THAT is why it is so expensive. I guess it makes sense now.

I've been thinking about a way how you can grow algae and use solar energy in the same location. The solar panel absorbs all light (or as much as possible) except for the green and yellow wavelengths. This is also useful for greenhouses as well. So does anyone know what material does this?

 

[Ivan Seeking]

So THAT is why it is so expensive. I guess it makes sense now.

I've been thinking about a way how you can grow algae and use solar energy in the same location. The solar panel absorbs all light (or as much as possible) except for the green and yellow wavelengths. This is also useful for greenhouses as well. So does anyone know what material does this?

Plants don't absorb much green light. That's why you see it reflected.

https://algaeresearchsupply.com/pages/lighting-for-algae-cultures

Each strain has a unique PAR fingerprint - Photosynthetically Active Radiation.

 

[sophiecentaur]

I suggest you plant some trees instead.

Some plants are pretty efficient at carbon capture but, at the end of their productive life, the trees need to be felled and stored, to make room for more trees.

The stored trees must be stored under conditions that will stop them decomposing again and releasing all the stored CO2. Fill the old coal mines with wood? Not a high enough density to do the necessary. Problems problems.

Instead they let their greed blind them

It's easy to blame someone else (big business) but, for decades, we (the public) have ignored the situation and not even considered changing our lifestyles to help with the problem.

Let's face it, we have been "blinded" by our comfortable life styles and by the convenience of carbon based energy. When do we ever fight against the marketing? Any government that tries to alter our life styles gets voted out PDQ. (If I am pointing a finger then it's at myself as much as anyone else)

 

[Rive]

The stored trees must be stored under conditions that will stop them decomposing again and releasing all the stored CO2. Fill the old coal mines with wood? Not a high enough density to do the necessary. Problems problems.

Only, if you are obsessed with carbon capture. If you are just about using the wood (replacing something else with wood) then it'll be at least carbon neutral. Worst case: you have some carbon neutral firewood.

Still beats a pool (cement, bricks) with plastic foil (fossil oil) and water (pumped mostly by fossil energy source) what would (maybe) produce some sushi nori.

 

[sophiecentaur]

Worst case: you have some carbon neutral firewood

Which is really not a good enough target, if we are seriously intent on improving things. If you want to have an effect, grow the trees, store them and wear thicker clothing.

 

[Ivan Seeking]

Some plants are pretty efficient at carbon capture but, at the end of their productive life, the trees need to be felled and stored, to make room for more trees.

The stored trees must be stored under conditions that will stop them decomposing again and releasing all the stored CO2. Fill the old coal mines with wood? Not a high enough density to do the necessary. Problems problems.

It's easy to blame someone else (big business) but, for decades, we (the public) have ignored the situation and not even considered changing our lifestyles to help with the problem.

Let's face it, we have been "blinded" by our comfortable life styles and by the convenience of carbon based energy. When do we ever fight against the marketing? Any government that tries to alter our life styles gets voted out PDQ. (If I am pointing a finger then it's at myself as much as anyone else)

Algae is far more efficient at carbon capture. You can grow it in the deep ocean and then let it die and sink. The captured carbon will be trapped by the high pressure and low temperature. Techtonic motion carries the algae underground where it is eventually converted to petroleum. That's how we got a good percentage of the petroleum we have used in the first place.

The fastest growing algae can double in mass in 18 hours. While most algae does not grow that fast, almost all strains double in mass in no more than a few days to a week.

 

[Rive]

Which is really not a good enough target, if we are seriously intent on improving things. If you want to have an effect, grow the trees, store them and wear thicker clothing.

On DIY level it's still better option than growing sushi nori.

While on industrial scale, trees and algae are simply not mutually exclusive. You can have them both (with both having their own different side benefits).

 

[sophiecentaur]

On DIY level it's still better option than growing sushi nori.

Does that include the transport cost of shop bought sushi? lol.

 

[Rive]

Yes. The 'initial investment' absolutely makes it so.

If you (DIY) plant a piece of corn (in some free soil), you have no initial investment to speak of. Same for a tree. Same for every soil based plant. You just get a free lunch, almost literally.

But growing (edible) algae requires quite an effort and materials to be invested. Just to make it carbon neutral during running is difficult (that's what's most of this topic is about). Getting back the initial investment (it's still about the 'invested' carbon footprint!) is even more difficult.

So: sorry, but if it's about 'saving the Earth', then you are still better of with ordering that occasional sushi nori.
If you want, you can also compare the carbon footprint of importing your few pieces of tropical fruits vs. growing them in a greenhouse.
Of course it's even better to not eat tropical fruits (no sushi), but that was not listed here as option.

 

[sophiecentaur]

Of course it's even better to not eat tropical fruits (no sushi), but that was not listed here as option.

I don't fancy the idea but we should probably all get used to eating a more medieval diet. In-season veg is very limited in wintertime but very low carbon.

 

[Rive]

Well, kind of. But I don't think it's that dramatic. As cooking goes international and we are getting better with preserving food there are plenty of new and interesting foodstuff becomes available locally (as farmers catching up). Some things will likely become luxury (again), but the variety may still increase.

Of course, only if people makes the effort. Nothing will affect a lazy breaded meat - mashed potato diet

Sushi is also not exactly a good example. If it's about healthy food and not about saving the planet, then the negative carbon footprint is not needed for growing algae and it can become industrial pretty fast, anywhere, locally.

Depends on the focus and demand.

 

[sophiecentaur]

As cooking goes international

It's not the cooking that matters. It's where the food comes from. People just assume everything is available from everywhere. That is not a sustainable attitude toward resources.

 

[Ivan Seeking]

It's not the cooking that matters. It's where the food comes from. People just assume everything is available from everywhere. That is not a sustainable attitude toward resources.

What if all food transportation was carbon neutral?

 

[Rive]

It's not the cooking that matters. It's where the food comes from.

Sure. But farmers do catching up.