19 thoughts on “Carbon capture idea”

  2. I don’t know, whenever you see a bunch of AI / “machine learning” hype about growing pond scum in plastic tubes, I start to get a vapor-ware vibe. Keep in mind that these boxes are “more efficient than trees” because they use artificial lighting. If you surround trees (or any fast-growing plants) with artificial grow-lights, they get a lot more efficient per acre too. I suspect these boxes are Musk-model businesses, depending on some state regulation, subsidy, or credit that a building owner can get by plugging them in and siting them near the HVAC exhausts.

    On the other hand we could turn some giant lakes into huge stagnant (and otherwise dead) algae-ponds with some pesticide treatment to keep down the mosquitos and probably suck up megatons of carbon. Don’t tell the Europeans! They’ll revive a revision to Sorgel’s Atlantropa plan and dam the strait of Gibraltar and turn the whole Mediterranean into the world’s largest carbon sink.

    As far as crops go, eventually we’ll reach a natural-limits plateau of increasing yields per acre as we reach the end of selecting breeds that can take up more nitrogen fertilizer to the point of “burn” toxicity untill 100% of their nitrogen needs are outsourced to the (CO2 producing) chemical industry, freeing up photosynthesis energy for synthesizing carbs and protein. Ironically, higher CO2 levels are increasing yields and reducing irrigation requirements (just ask any greenhouse grower). There is some recent evidence, however, that, correcting for weather volatility, the trend since 1940 has already started to flatline for many crops. European wheat yields are more or less what they were 20 years ago, and rice is in a similar situation in many major growing regions.

    There is still plenty of unused or inefficiently-cultivated arable land in Africa though, and that’s where most of the new food will be needed anyway.

      • Beware of perpetual motion machines. Unless this thing is powered by carbon-free energy, the net carbon reduction is probably also negative.

    • ..and turn the whole Mediterranean into the world’s largest carbon sink.

      Sink is the key technology missing from these plans that involve an increase global biomass production. The Black Sea already has a deep dead zone. Whether or not this area is enough is irrelevant without a plan to precipitate the carbon out of the system. What biomass can you grow at a rate faster than the accumulation of atmospheric CO2 and sink/bury/treat it so it doesn’t decompose back into CO2 and do it all cost effectively? The type of biomass and where it is grown is only important if it involves stopping the resulting hydrocarbons from converting back into CO2.

      Algae bioreactors, azolla seas, and greening North Africa fit into the normal carbon cycle. We need to solve the sink.

      • When simple aquatic life dies the remains often literally sink down to the cold bottom where decomposition is slow and pressure high so the CO2 released tends not to bubble up very much. If it’s deeper than 3000 meters, the CO2 will become liquid denser even than high-pressure salt water, so stay at the bottom, which is why “ocean storage” is one proposal out there.

        Some big, deep lakes in craters over volcanic formations absorb and hold onto a lot of CO2 coming out of the vents to the point of super-saturation but even then, with apparently only very slow release to the atmosphere, so calm water can hold a lot for a long time.

        Unless there’s an earthquake or eruption, in which case it suddenly bubbles up and releases all at once like shaking up a can of soda.

        That’s what happened at Lake Nyos in Cameroon in 1986 just a few months after Chernobyl, in a natural event that probably killed more people than the nuclear incident, but which most people never heard of. There was a seismic event, the lake released a huge amount of CO2 (and some other toxic gases) at once, and, being denser than normal air, the cloud descended on the locals and by asphyxiation quickly killed nearly 2,000 people and a bunch of animals.

        The French helped install giant straws from the bottom to the top of the lake, which, once primed and got going, carry on by themselves spontaneously with nothing more than “effervescence” energy to continue the glow and de-gas the lake.

        Then they discovered that Lake Kivu was also super-saturated in the same way, and was 2,000 times bigger than Nyos. They put giant straws in there too. Historically, it looks like Kivu had some kind of similar event about every millennium or so, and one can imagine that those must have seemed terrible and supernaturally epic disasters to anyone who experienced it on the margins and survived it or who saw the aftermath.

        • I think you are making my point. The critical component in any intervention designed to offset CO2 emissions is removing carbon from the system (i.e. the sink). It is obviously possible otherwise we wouldn’t have fossil fuels to begin with.

          Schemes designed to increase biomass production alone are not solving the core issue.

  3. This is great marketing that targets customers who wish to signal their concern for the environment. The question remains whether there is anything technically newsworthy behind the marketing language.

    Besides the fact that this technology has zero climate impact without sequestration (i.e. prevent the CO2 resulting from the decomposition of the algae from re-entering the atmosphere) the article and company press release do not mention the key factors that would indicate true innovation (say cost per ton of converted CO2 or efficiency in converting sunlight to biomass compared to other natural/domesticated autotrophic systems). Ultimately this is about sunlight and chlorophyl and the forest comparison feels like arm waving, especially if the comparison is between aquatic algae and terrestrial C3 plants. As a rough first estimate, the technology has to produce algae that is significantly cheaper (eventually orders of magnitude cheaper) than the cost of an equivalent barrel of oil and this is before factoring in the cost of sequestration.

    Bioreactors for autotrophs may be an important technology for carbon capture but I’ve read nothing to indicate any kind of innovation in this particular bioreactor beyond the creative use of buzz words. Perhaps that information can be found somewhere else.

  4. I looked at the energy efficiency of trees, photo synthesis. It converts about 3% of the sun into usable plant energy (sugars). There is some dispute here. A solar panel can produce electricity with almost 20% efficiency, but the electricity is unstable, needs separate storage.

    Combine the two, a solar powered bioreactor., The bioreactor need efficiency above 6% or so to be viable and cover equipment costs. In other words, take a forest of trees, cur them down and use them to build a wodden bioreactor and build solar panels. Find the equivalent capital costs in tree wood, subtract off the 3% add on the 6%, and subtract the construction costs in units of wood (your basic raw material).

  5. Even if — especially if — this works as well as claimed, it will go nowhere. Environmentalists never show any interest in such proposals. Environmentalism is about imposing restrictions, not about obviating the need for restrictions.

    • You need 400 million to cover our transportation needs, if the co2 can be captured with something like 10% equivalent total solar equivalents. Meaning, total cost energy at the vehicle.

      My numbers are ball park, not close, but I did this calculation a few times. Electric gets collection energy at 20%, but the extra energy cost to store it is a nightmare of capital investment. I think electric, used on the spot, to remove CO2 is the best current technology, in units of CO2 removed vs land area used. But how is the CO2 stored? Ignoring storage, I can envision and energy machine that removes the CO2 equivalent to photosynthesis at 30%, but I do into count the electrons being spun into usable energy, the co2 sits somewhere for free; a bad assumption, like assuming lithium mining is free. But given my error, the number of acres needed is much less, maybe 200-300 million. Then let us assume the acres available include off shore floating systems, then my acreage of land can go as low as maybe 100 million acres.

      I make the case that we should focus on artificial lungs, replace the Amazon with concentrated CO2 mechanical breathing machines. Each nation willing to devote maybe a fifth of land area.

  9. My plan, above, to build artificial CO2 lungs has one other advantage, it interrupts and control the carbon cycle, we can pick the temperature we want over 20 year periods. The formula is acreage in CO2 out, and that is how to price carbon. The best approach is either solar direct to CO2 removal; or Solar direct to algae fuel.

    The cost in terms of energy input is converted into acres of equivalent solar electricity, for example, then acres is a great measure of CO2 efficiency, what is the equivalent artificial lung size. Mankind ultimately chooses glacial, sunny, or mid cycle. A great deal of GDP devoted to carbon management.

  10. Is total farmland actually decreasing? Like, worldwide? I assumed that it’s constant or expanding, but it’s contracting in some places (e.g., the US) and expanding in others (e.g., Brazil).

  11. Hmmm. I like trees. I like looking at trees. I sort of like the idea of planting trees – take the sixth graders out, let ’em hold some seeds and push a shovel into the ground and get a little dirt on their hands — kind of a social bonding thing, like maybe conservatives ought to approve of. A bunch of kids staring at metal sided boxes on rooftops being told they’re looking at “bio-reactors” isn’t the same thing. And we’ve got lots of room in this country to plant trees.

    Another thing. Most trees in cities are pretty dinky things — twenty, maybe twenty five feet tall. That’s a policy, I gather — they’re shrubs really, intended to grow up quickly, but just so far. Keep the root space small, keep the height on a par with the dinky buildings around them, keep the branches out of overhead wires, aim for uniform size and uniform spacing, and so on. Maybe it’d be a idea to allow thirty foot high trees, or even bigger — more leaves, bigger trunks, lots more CO2 storage, probably not too much more cost.

    I suppose it’s easier to drop bio-reactors on rooftops than to get the average city council to change its tree height regulations.

Comments are closed.