Algae carbon capture

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But it is fairly easy to make some oil... at $30 a gallon
Yeah, if somebody has some talent for chemistry then it can be done even from chickens :approve:

I was finally able to produce a model that was energy net positive but it was painstaking.
Quite a feat, I would say :bow:

Really rare to care about such 'small' details.
 
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Ivan Seeking
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And then, the carbon footprint. One would think that the lesson of other biofuels (many of them with bigger carbon footprint than classic oil) got learned by now.
I sort of derailed this thought with my comments about energy. But they are essentially the same problem. If the system is truly energy net positive then it is likely carbon neutral. By closing the system and only powering the farm using fuel produced onsite, the idea of stealing energy and leaving a carbon footprint is mostly moot. But all inputs to the system have to be considered. And nitrogen was a big one!

And as it turns out, in my own efforts the generator engines become critical components of the system in several ways. For example, in addition to the nitrogen supply for fertilizer from the NOxs produced, we can capture additional CO2 needed to accelerate algae growth. The engine's high temps and pressures also act as an air purifier and kills any potential biological contamination. Everything coming out of the exhaust can be captured and recycled for the next batch of algae. This all helps to eliminate or reduce energy losses.
 
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Note also that the generator exhaust is significant. In all likelihood, half of the fuel produced is needed just to run the farm. So on the average, half of everything from the last crop is being burned in the generator engines and fed to the current crop as nutrients.

It may be reasonable to use the biomass [fiber] from the processed algae as another source of nutrients and energy through combustion. But that is also a high-quality feed for cattle. Either way an algae farm at scale will produce vast quantities of biomass that can be used or sold.
 
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It may be reasonable to use the biomass [fiber] from the processed algae as another source of nutrients and energy through combustion. But that is also a high-quality feed for cattle. Either way an algae farm at scale will produce vast quantities of biomass that can be used or sold.
Difficulties at every corner. If you remove biomass from the loop, you need to replace the relevant nutrients (at a cost of increased footprint).
If you don't utilize the surplus biomass, then you run on deficit.
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:
 
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Difficulties at every corner. If you remove biomass from the loop, you need to replace the relevant nutrients (at a cost of increased footprint).

That is mostly carbon, oxygen, and hydrogen. So again the biggest concern is a water supply.
 
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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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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.
 
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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/
 
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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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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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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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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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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.
 
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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?
 
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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
 
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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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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).
 
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...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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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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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 o_O
 
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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.
 

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