Chemical/Paint Algae Carbon Capture: Make Your Own Algae Tank & Absorb CO2

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Concerns about climate change are driving interest in algae carbon capture as a potential solution for CO2 absorption and biofuel production. While creating personal algae tanks is a popular idea, experts emphasize that individual efforts may have minimal impact on global carbon levels. Large-scale algae farming is complex and requires significant resources, with economic feasibility being a major challenge. The discussion highlights the need for innovative approaches, such as closed bioreactors and ocean farming, to effectively harness algae for carbon capture and fuel. Ultimately, prioritizing carbon footprint reduction remains crucial in addressing climate change.
  • #31
Rive said:
It may look good on first sight to incorporate the cattle into the loop, but bringing back the nutrients through manure into the loop is difficult since you have to avoid the biological contamination of your pools.

Compost heaps and the heterogeneous nature of soil life can cover up so many trouble in classical agriculture :doh:

Yes, the use of something like animal fertilizer is impractical. The bacteria would run amok and contaminate the entire system. If the fertilizer is sterilized then you have probably just killed your energy budget.

Algae can be used to remediate contamination but that likely isn't going to be a high-yield strain.
 
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  • #32
Ivan Seeking said:
That is mostly carbon, oxygen, and hydrogen.
Cattle just burn carbohydrates, but does not really live on it: the nutrients (missing from the pool) makes the difference.
If you can have (only) carbohydrates (you can sufficiently separate them), then maybe you can aim for alcohols instead, and keep the (still mostly sterile) nutrients within the loop.
 
  • #33
Rive said:
Cattle just burn carbohydrates, but does not really live on it: the nutrients (missing from the pool) makes the difference.
If you can have (only) carbohydrates (you can sufficiently separate them), then maybe you can aim for alcohols instead, and keep the (still mostly sterile) nutrients within the loop.

On the fatty acid side of things, some groups were having luck migrating the oil out of the algae without having to kill the algae. I believe they were using ultrasound. I have not heard of anything along those lines for the sugar. Also, I don't know how that affected later yields.

The biomass remaining after removing either sugar or oil is a source of protein.

Seaweed and microalgae are considered a viable source of protein. Some species of seaweed and microalgae are known to contain protein levels similar to those of traditional protein sources, such as meat, egg, soybean, and milk [3,4]. Algae use for protein production has several benefits over traditional high-protein crop use in terms of productivity and nutritional value. Seaweed and microalgae have higher protein yield per unit area (2.5–7.5 tons/Ha/year and 4–15 tons/Ha/year, respectively) compared to terrestrial crops, such as soybean, pulse legumes, and wheat (0.6–1.2 tons/Ha/year, 1–2 tons/Ha/year, and 1.1 tons/Ha/year, respectively) [5]. Terrestrial agriculture already requires approximately 75% of the total global freshwater with animal protein in particular requiring 100 times more water than if the equivalent amount of protein was produced from plant sources [6,7].
https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5447909/
 
  • #34
CCatalyst said:
Is it not true that if we were to bring our net carbon dioxide output to zero, we would still be past the point of no return? The carbon dioxide in the atmosphere is still causing elevated temperatures, resulting in more forest fires, resulting in more carbon dioxide, resulting in more elevated temperatures, resulting in more forest fires and so on?
I strongly suspect that the first, or one of the first attempts at geoengineering to reduce warming, will be to release substances into the upper atmosphere that will reflect some percentage of sunlight away before it can cause any warming of the planet. I remember that Alcoa Aluminum had a patent on a bright-white aluminum oxide powder that can be added to jet fuel. The jets fly at 30,000+ feet and release the powder in the engine exhaust. At that point the powder is light enough to stay aloft for up to two years or so. I did a quick search to find a report on that and didn't spot it yet.

What follows is from a recent effort to explore this technology. Environmental concerns have temporarily stopped the testing planned but this is just one example. This idea has been debated and planned for probably 30 years now.

Scopex is intended to better understand one form of solar geoengineering: injecting substances into the air to reflect some of the sun’s rays back to space and thus reduce global warming relatively quickly.

Solar geoengineering has long been a subject of intense debate among scientists and policymakers, often seen as a desperate, potentially dangerous measure that could have unintended consequences
https://www.nytimes.com/2021/04/02/climate/solar-geoengineering-block-sunlight.html

We may soon decide that the risk of not reducing warming is greater than the risk of spreading aluminium oxide, or other compounds, all over the planet.

Can we reflect sunlight to fight climate change? Scientists eye aerosol shield for Earth.​

https://www.space.com/global-warming-aerosol-reflector-block-sunlight
 
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  • #35
Despite the early stage of the research, the working group maintains that aerosol intervention appears to be a relatively attainable method of cooling Earth. "The costs and technology needed to reflect the sun's heat back into space are currently more attainable than other climate intervention ideas like absorbing carbon dioxide from the air," the working group said in a statement.
https://www.space.com/global-warming-aerosol-reflector-block-sunlight

As for the core problems, as mentioned one essential problem is that the free market does not lend itself to fighting climate change. When push comes to shove, people generally choose the most economical option. On the average, people won't voluntarily pay twice the price or more for a carbon-neutral fuel. And industry and commerce depend on competitive energy prices in order to compete with foreign producers - the global market is capitalist.

I was convinced back in 2008 that with a WWII sized effort, for the price of an Iraq war, we could convert a significant percentage of the energy supply to carbon-neutral algal fuels, in five years. But we are still too busy arguing about what is and is not real. The problem is not the science. The problem is political. So maybe that is the real answer here. After doing what you can personally, the best way to fight climate change is to win hearts and minds. We need the majority of the population to support the needed changes. And we need a clear plan that takes economic realities into account.

In my opinion, fuels derived from algae are the best carbon-neutral fuel options. And we must have carbon-neutral fuels. There is no practical path to a solution without them.
 
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  • #36
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.
 
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  • #37
CCatalyst said:
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.
 
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  • #38
Ivan Seeking said:
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.
 
  • #39
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?
 
  • #40
CCatalyst said:
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
 
  • #41
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.
 
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  • #42
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).
 
  • #43
Ivan Seeking said:
...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.
 
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  • #44
Rive said:
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!
 
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  • #45
Ivan Seeking said:
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.

Ivan Seeking said:
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.

Ivan Seeking said:
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 o_O
 
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  • #46
Rive said:
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.

Rive said:
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.

Rive said:
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/

Rive said:
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.
 
  • #47
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?
 
  • #48
CCatalyst said:
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.
 
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  • #49
CCatalyst said:
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.
 
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  • #50
  • #51
Ivan Seeking said:
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?
 
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  • #52
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.
 
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  • #53
BillTre said:
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

 
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  • #54
Botryococcus Braunii is considered to be the beginner's strain. It can allegedly produce yields of oil up to 75% by weight.
 
  • #55
How do you harvest the oil, from mashing up the cells?
 
  • #56
BillTre said:
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.
 
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  • #57
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?
 
  • #58
CCatalyst said:
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.

1632020150621.png

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

Each strain has a unique PAR fingerprint - Photosynthetically Active Radiation.
 
  • #59
Rive said:
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.
CCatalyst said:
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)
 
  • #60
sophiecentaur said:
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.
 

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