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Earth Power Science Technology

Researchers Propose Solar Methanol Island Using Ocean CO2 (arstechnica.com) 251

A PNAS paper published this week outlines a plan to establish 70 islands of solar panels, each 328 feet in diameter, that sends electricity to a hard-hulled ship that acts as an oceanic factory. "This factory uses desalinization and electrolysis equipment to extract hydrogen gas (H2) and carbon dioxide (CO2) from the surrounding ocean water," reports Ars Technica. "It then uses these products to create methanol, a liquid fuel that can be added into, or substituted for, transportation fuels. Every so often, a ship comes to offload the methanol and take it to a supply center on land." From the report: The researchers estimated that we would need approximately 170,000 of these solar island systems to be able to produce enough green methanol to replace all fossil fuels used in long-haul transportation. While that seems like a lot, it's theoretically possible, even if we restrict these systems to ocean expanses where waves don't reach more than seven feet high and there's enough sunlight to meet the system's yearly average need.

Still, the authors admit that this is just the description of a possible prototype: whether it's practical to build or not will depend on the cost of the technology that supports the system, as well as the cost of competing forms of energy used in transportation. Cleaning and maintaining this equipment in a marine environment is also a concern, and the researchers admit that there may be room for alternate setups (like making another fuel instead of methanol) that might make more economic sense. For now, though, it's a compelling idea to avoid additional fossil fuel extraction that is within reach using existing technology.

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Researchers Propose Solar Methanol Island Using Ocean CO2

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  • Good idea (Score:5, Interesting)

    by Errol backfiring ( 1280012 ) on Friday June 07, 2019 @06:14AM (#58724060) Journal
    Well, this is a good idea. Especially ships can be rather polluting. In other [duurzaamnieuws.nl] news (article in Dutch about all cruise ships world wide polluting ten times more than all the European cars together), ships appear to use more dirty fuel than cars. There is therefore a lot to win in pollution by ships.
    • Re:Good idea (Score:5, Interesting)

      by AmiMoJo ( 196126 ) on Friday June 07, 2019 @06:22AM (#58724066) Homepage Journal

      Why bother with floating solar islands when you can just use floating wind turbines? The tech already exists and is now starting to get deployed on a large scale, in difficult environments like the North Sea.

      Build enough turbines that they can provide base load due to geographic distribution (there is always enough wind blowing over a wide area). When there is excess wind use it to extract hydrogen from water. It's inefficient but who cares, the energy is almost free. Then you can run vehicles that can't go battery electric on hydrogen instead, the only emission being water.

      • by crow ( 16139 )

        They're talking about putting these where the waves don't get very high, so I suspect that also means the winds generally aren't that strong in these locations. But you certainly have a point that the same idea works with other power sources. You could even put in a nuclear reactor like those found in submarines or aircraft carriers. It mostly boils down to economics.

        • It mostly boils down to economics.

          Yeah, that's the problem. Everybody asks if it's worth the money. They never ask if it's worth the effort.

      • by Shaitan ( 22585 )

        We likely need both with your proposed solution only using excess energy. The wind solution involves moving parts so will be far less durable. Wind turbines also disrupt wind patterns and that could be a problem over the course of time. That is probably a wash since obviously the solar solution would impact ocean heating and therefore currents. Lastly wind turbines are bird slayers.

        • Wind turbines also disrupt wind patterns and that could be a problem over the course of time.
          For this kind of mental problem I suggest: a beer and less writing on /.

        • by AmiMoJo ( 196126 )

          Anything at sea involves moving part, which are less of a problem than seawater and salt anyway.

          • by Shaitan ( 22585 )

            "Anything at sea involves moving part"

            Or an anchor. But those parts are in common between the two solutions and generally less sensitive than the bearings in the turbine itself.

            "which are less of a problem than seawater and salt anyway"

            They aren't isolated problems. The seawater and salt are also a problem for continued operation of the turbine itself. Including building up and clogging it so that it introduces additional friction that would reduce output and could even freeze the turbine. The solar panels

      • It's inefficient but who cares...

        Do you really need it explained to you that the math matters?

      • Why bother with floating solar islands when you can just use floating wind turbines?

        Why bother with floating solar panels or floating wind turbines when we can use floating nuclear power plants?

        • by AmiMoJo ( 196126 )

          Floating nuclear plants are more expensive to build and operate. Also you can't get insurance for them.

      • It's inefficient but who cares, the energy is almost free.

        The energy may be free but the windmills are not.

        The windmills cost money and so the electricity and hydrogen produced will cost money. This cost must compete with other sources for these products. If it cannot produce at competitive prices then it will not be profitable. Without profit the process cannot find investors or keep employees.

        If wind power is so cheap then why do the windmill owners demand so much in government subsidies? I say end the subsidies since they think it's so cheap we can use it f

      • The paper also raises the wind turbine issue. Either would work.

        When there is excess wind use it to extract hydrogen from water. It's inefficient but who cares, the energy is almost free.

        Well, they want to combine the H2 gas with CO2 to (a) pull CO2 out of the ocean, (b) make a liquid (methanol) that's easier to handle than a gas and (c) works in liquid fueled engines already, avoiding the need to convert to new engine types.

        Then you can run vehicles that can't go battery electric on hydrogen instead

        Thei

    • Well, this is a good idea.

      Is it really? Because it doesn't sound like a very good idea. I have no idea how this proposal will prove to be economical and it doesn't sound like the people proposing it have given the matter much thought either. Not to mention it only is a viable solution if it is substantially cheaper than extracting hydrocarbons out of the ground and that seems very unlikely.

      • Well, this is a good idea.

        Is it really?

        Yes, because it produces liquid fuels and there's a whole demographic of holdouts who refuse to buy electric vehicles because can't be refuelled in a couple of minutes.

        • by jwhyche ( 6192 ) on Friday June 07, 2019 @09:52AM (#58724800) Homepage

          Yes, because it produces liquid fuels and there's a whole demographic of holdouts who refuse to buy electric vehicles because can't be refuelled in a couple of minutes.

          While there are a few that fall into this category, but mostly its a good ideal because it can replace fossil fuels in vehicles where electrification isn't practical. Such as long haul trucks. The energy density just isn't there, yet, to store enough electricity in batteries for long haul trucks to be practical using this method. I imagine the same can be said for ships and aircraft.

          Contrary to wishful thinking heat engines are not going to completely go away anytime soon. There will always be those places where they will be more practical than electric. Best to find a cheap environmental fuel for them as soon as possible.

          • There will always be those places where they will be more practical than electric.*

            * For a finite value of "always".

        • there's a whole demographic of holdouts who refuse to buy electric vehicles because can't be refuelled in a couple of minutes.

          That's mostly just in your head. Viable electric cars are nearly brand fucking new and so far, there's only one serious player with mere three models, two of which are luxury models (!). This is entirely a manufactured controversy and you've swallowed it hook, line and sinker. In the end, this situation remains orthogonal to any feelings and emotions involved; supply and demand of vehicles [and the energy required to operate them] will be the determining factor.

        • Yes, and those guys are idiots.
          In 50 years combustion engines will only be in antique cars and probably military. Only very few privately owned will remain.
          You basically only have strong reasons to have one in places like Alaska and Siberia.

        • Yes, because it produces liquid fuels and there's a whole demographic of holdouts who refuse to buy electric vehicles because can't be refuelled in a couple of minutes.

          Liquid fuels also have a substantial energy density advantage over batteries. A Tesla 3's 75 kWh battery pack (270 MJ) weighs 480 kg [slashdot.org], for a specific energy of 0.56 MJ/kg.. Gasoline has a specific energy [wikipedia.org] of 46.3 MJ/kg, or nearly two orders of magnitude higher. Methanol is 19.7 MJ/kg. Some of this advantage is lost due to the ~20% efficienc

    • by dargaud ( 518470 )
      Just read a paper that estimates to pollution from ships to cause 260 000 death PER YEAR ! I re-read it several times as I first thought it was a typo. And some people complain about nuclear power plants...
    • ships appear to use more dirty fuel than cars

      Big ships have huge engines with steam preheaters to soften up viscous, unrefined, cheap, nasty oil so they can burn it. It's so bad they have rules near ports they have to switch to better fuels because it causes so much pollution.

      But they are working on it
      http://www.imo.org/en/MediaCen... [imo.org]

    • But you don't need to synthesize methanol for that. You just need to ban sulfurous fuels on ships. That's still way cheaper.
    • Well, this is a good idea. Especially ships can be rather polluting. In other news (article in Dutch about all cruise ships world wide polluting ten times more than all the European cars together), ships appear to use more dirty fuel than cars. There is therefore a lot to win in pollution by ships.

      Wouldn't it be cheaper and easier just to go back to sailing ships for most cargoes? It's not like we send much of anything by sea that is time-critical....

    • Not all pollution is the same. SOx emissions especially are almost irrelevant to the environment providing we don't release them in a concentrated form in a population centre. Unfortunately it's the SOx emissions that are compared to cars which is sensationalist bullshit given that cruiseliners are pretty damn bloody horrid with CO2 emissions and other pollution that matters as well. But as usual the media jumps on the worst number and cries foul!

      Anyway I learnt something today: duur=expensive, so I didn't

    • Depending what you call "pollution", a single cruise ship produces as much pollution as 1 million cars.

  • Economics? (Score:5, Interesting)

    by sjbe ( 173966 ) on Friday June 07, 2019 @07:34AM (#58724274)

    A PNAS paper published this week outlines a plan to establish 70 islands of solar panels, each 328 feet in diameter, that sends electricity to a hard-hulled ship that acts as an oceanic factory. "This factory uses desalinization and electrolysis equipment to extract hydrogen gas (H2) and carbon dioxide (CO2) from the surrounding ocean water," reports Ars Technica. "It then uses these products to create methanol, a liquid fuel that can be added into, or substituted for, transportation fuels. Every so often, a ship comes to offload the methanol and take it to a supply center on land.

    Ok let's stipulate for the sake of argument that this is technologically possible. It still doesn't explain the economics of it and that isn't a trivial concern. It doesn't matter AT ALL if they can build the thing if it doesn't have an economic payback within a reasonable period of time. Gut feeling is that I have a hard time seeing something like this actually turning a profit.

    Here are several of the reasons why I'm dubious of the economics
    A) Anything on the ocean necessarily involves a LOT of upkeep and by extension cost
    B) It's not at all clear how efficient this process is at doing what it claims
    C) It's going to be complicated to design, build and operate and complexity = cost
    D) It's not clear what problem this solves that would not be more economically solved via other (simpler) methods
    E) How exactly is mining CO2 from the ocean and releasing it into the atmosphere going to mitigate climate change given that we aren't going to stop pulling hydrocarbons out of the ground any time soon. (because it's almost certainly cheaper than this "solution")

    While that seems like a lot, it's theoretically possible, even if we restrict these systems to ocean expanses where waves don't reach more than seven feet high and there's enough sunlight to meet the system's yearly average need.

    Is there actually a place on the ocean where the waves never get higher than 7 feet? That seems improbable to me. It would have to be near a coast and frankly if it depends on oceans staying placid I think it's doomed from jump street.

    • How exactly is mining CO2 from the ocean and releasing it into the atmosphere going to mitigate climate change given that we aren't going to stop pulling hydrocarbons out of the ground any time soon. (because it's almost certainly cheaper than this "solution")

      A percentage of atmospheric CO2 we release is dissolving into the ocean, rather than acting as a greenhouse gas. It's one of the few things that is making global warming not as bad. However, it's also turning into carbonic acid as it dissolves, which

      • A percentage of atmospheric CO2 we release is dissolving into the ocean, rather than acting as a greenhouse gas. It's one of the few things that is making global warming not as bad.

        No, it's one of the things that is making climate change not as bad YET. The ocean does not have infinite capacity to absorb CO2 and there appears to be evidence we are or soon will be exceeding the carrying capacity by some meaningful amount if we desire to keep the climate close to what it is now.

        Therefore, pulling the CO2 in the ocean may be even more important pulling it out of the air, although the CO2 can move between the two.

        Correct which is why this technology makes little sense because we need to be leaving it in the rocks where it already was or finding ways to put it back there. Moving CO2 between the water and air accomplishes

  • This batch of ivory tower thinking is in desperate need of some common sense.

    The objective is to turn seawater into methanol. Why do you need to be somewhere in the the ocean to do this? Is there a fear that this can only be done in international waters?

    They actually propose building floating solar power plants. This adds a lot of expense and complexity for little or no gain. It adds expense as saltwater will greatly increase maintenance costs. The fact that they are on the ocean greatly increases costs as you can't readily fix them. It is inevitable that storms will damage them and knock them loose from moorings where they will become an environmental hazard. They also want to build their desalination processing plants on the water.

    A dose of common sense increases the feasibility and reduces the cost of this proposal by an order of magnitude.

    Simply build the plants near the seashore. You can run a pipe to the ocean to get saltwater and run power lines from solar power plants on land to provide power. You can then run a pipeline to export the methanol. You can run a second pipe to export a byproduct of the desalination process called fresh water. You could even be environmentally smart and put the plant somewhere where there is a shortage of fresh water. There is absolutely no real world benefit to putting this operation on the ocean.

  • It's just an idea. It's not intrinsically unworkable if the technology supports it. If not feasible right now, perhaps in the future.
  • In South India they describe a process to catch cranes. All you need to do is to put some butter on the head of the crane. The sun will melt the butter and it will drip down and blind the crane and other waterfowl. They will be easy to catch once they are thus blinded.

    This technique is very similar. Floating solar panels, then make hydrogen and then make methanol and use it in infernal combustion engine delivering 30% efficiency. Yay! Victory.

    The battery prices are crashing. Halving every seven years, and there is no end in sight. Already on-ground solar plus storage is displacing peaker power plants. The battery electric cars are cheaper than gasoline cars in the F and E segments (>100K and > 50K). They have TCO parity in D segment (>35K). Price parity is expected in two years. TCO parity in C segment (>25K) at the same time. Why go through this complex process?

    • The battery prices are crashing. Halving every seven years, and there is no end in sight.

      And CPUs are doubling in speed every 18 months! Exponential growth is great but unsustainable.

  • Green energy is great but the cost (energy supplied in the process) and maintenance (long-term commitments) of them is often greater than nuclear and other forms of dense energy production.

    This sounds like a great concept but having worked technology for oil platforms, it's by no means simple. The wind itself is so filled with salty moisture that even without getting anything wet, things just rust out and between the chemical environment and the vibrations of the oceans even the solder joints in sealed boxe

  • Putting 100m square patches atop a living ocean will affect the ecosystem around them. This same problem exists with most land-based solar arrays; they affect the amount of sun received by whatever is behind them. Solar roofing is a more workable idea, since that shading by the solar array is already a function of the roof.

    Pulling CO2 that would normally be absorbed and converted to oxygen and plant matter will affect the ecosystem. Pumping atmospheric CO2 though a biomass of algae, then converting that to

  • Comment removed based on user account deletion
  • Fantasy miracle tech after fantasy miracle tech. Denial after denial. Just so we do not have to change anything. It will not work. Conditions will already get unpleasant on this planet. Unless emissions are drastically lowered, they may become deadly.

  • The late-great chemist George Olah outlined strategies and processes for what he termed "The Methanol Economy". Good to see some others continuing that work.

    https://www.technologyreview.c... [technologyreview.com]

  • Methanol is a crap fuel. It has the same problems as ethanol, notably the low energy density and hygroscopicity, plus it is horribly toxic. Just getting enough of it on your skin can cause blindness.

    If we want alternatives to current fossil-based motor fuels, we already have them. The gasoline replacement is called butanol [wikipedia.org], and the diesel replacement is called green diesel [wikipedia.org]. They can be made from algae, which we should be able to produce cost-effectively in open raceway ponds, at current oil prices. It's not as profitable as fossil fuels, but we need to stop using those whether they are profitable or not.

  • by rbrander ( 73222 ) on Friday June 07, 2019 @12:11PM (#58725586) Homepage

    The answer to every "Why Don't They" question has the same answer: Money. - R. Heinlein

    Well, no kidding it's all about the cost. If the cost isn't "compelling", then the idea is not. I'm also not sure why this has to be floating around on the ocean, vastly complicating maintenance of the panels. We have these "pipe" things that can suck up water a ways out from shore and pull it in, and there are large chunks of the earth that have big flat spaces near a shore.

    The fundamental proposition is to convert the 50,000 big ships in the world, mostly cargo carriers, to burning methanol, which can have several sources. It's a fair idea. It's economics are not "compelling", though, by existing means of production, much less an experimental new one.

    The existing ones leverage some chemical energy stored in the feed stocks, such as wood chips or corn or farm wastes; one that depends 100% on energy inserted into basic molecules by electricity is unlikely to make cheaper ethanol that we already have, at a guess.

    And what about the whole ethanol idea to start with? The "hydrogen crowd" are already pissed that they aren't getting hydrogen cars because batteries have seized the market, there. Any chance for the hydrogen fans in big transport engines?

    One thing does seem likely to me: even the 3% (?) of carbon emissions that come from those 50,000 ships have to be reduced somehow, and I doubt we're building 50,000 little nukes. (A cargo ship only runs on about 25,000 HP, I think, under 20MW, hardly worth a nuke.) I'm guessing it'll be either methanol or hydrogen.

    • by rbrander ( 73222 )

      Yoicks, ships are getting bigger. 80,000 HP is getting common. Still not enough to justify a nuke, though, especially tens of thousands of them.

  • Combustion engines are the past. Only an idiot would use electricity from solar power to make hydrocarbons, instead of using the electricity directly.

  • What else floats in the ocean and uses sunlight to extract CO2 from the water? Plankton [wikipedia.org]. With zero maintenance and R&D costs, even.

    Before we kill ourselves trying to come up with a technological solution for removing CO2 from the atmosphere, let's not forget that a natural one already exists. We just have to stop clear-cutting forests, start replanting more trees than we cut down, and bury the used trees to prevent them from releasing their extracted carbon back into the atmosphere as CO2 (wood an
  • It's carbon-positive. It takes vast amounts of energy for electrolysis to extract hydrogen from water, and vast amounts of energy to desalinate it, too. Then you're going to produce yet another 'fuel' that you burn, releasing CO2 back into the atmosphere? Nothing 'green' here at all.
    We need solar, wind, and nuclear power. Stop burning things, it's counter-productive.
  • What power density is this proposed to achieve? They're starting with solar, about 20% efficient, but only if the array is constantly maintained with a constantly running cleaning system to remove the salt spray that'll coat the panels, then using the power for desalinization, which needs a tremendous amount of power, and electrolysis to hydrogen, also a low-efficiency process, then conversion to methanol, which will also further reduce power output. Putting a few 1% efficiency conversions after electricit

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