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Power Upgrades

Solar Power Could Become a Catalyst For a Major Synthetic Fuel Upgrade (interestingengineering.com) 144

Posted by BeauHD from the greener-fuels dept.
An anonymous reader quotes a report from InterestingEngineering: As global carbon emissions that stem from fossil fuels keep adding to our ever-growing climate change issue, energy companies have turned their focus on renewables to generate fuel. One of those companies is Synhelion from Switzerland. The company harnesses the energy of the heat of the sun and converts the collected carbon dioxide into synthetic fuels, in turn offering a green and sustainable solution. The system is quite genius. Synhelion uses a mirror field filled with heliostats to reflect the radiation of solar power. The radiation is then concentrated in the solar receiver and turned into clean, high-temperature process heat at around 2.732F (1.500C). Next, the produced heat is turned into a CO2 and H2O mixture in a thermochemical reactor. The end product, the syngas, is then turned into gasoline, diesel, or jet fuel with a gas-to-liquid technology process. What makes this sustainable is the fact that the company's thermal energy storage (TES) saves the excess heat after each process which keeps the operation going 24/7.

And how does the solar receiver work? The company says the technology is inspired by nature. To reach ultra-high temperatures, the solar receiver mimics Earth's greenhouse gas effect. The chamber is filled with greenhouse gases that are usually water vapor or water and CO2 mixtures. After solar radiation collected with heliostats enters the chamber, the black surface of the chamber absorbs the heat, thermalizes, and re-radiates it. The greenhouse gas then absorbs the thermal radiation, acting as a heat transfer fluid (HTF), which can, later on, be turned into any type of liquid fuel. And liquid fuels are easy to transport which makes them low-cost compared to their solid counterparts. When there's no sun, the HTF flows through the TES in the opposite direction to recover the previously stored thermal energy. The hot HTF from the storage drives the thermochemical processes in the reactor that keeps the operation working. "The company states that through this technology, it can provide fuels at a cheaper price with a 50 to 100 percent lower carbon footprint compared to fossil fuels," the report adds. "In addition to Synhelion's aligned motives with the Paris Agreement's CO2 reduction targets, it is supported by larger industries looking to cut their emissions -- and eventually achieve net-zero -- by 2030."
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Solar Power Could Become a Catalyst For a Major Synthetic Fuel Upgrade More

Solar Power Could Become a Catalyst For a Major Synthetic Fuel Upgrade

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  • Don't use thousands separators. They are only confusing.

    Equally, don't simply copy and paste to generate summaries. Fucking summarize, you lazy fucks.

    • Re: (Score:2)

      by HiThere ( 15173 )

      I disagree, though I agree that the use of '.' as the separator is confusing. Either ' or , would be better. (Or various unicode symbols could work, but not on this site.)

      • The . is the correct separator in some locales. The apostrophe denotes minutes, whether of time or rotation. The comma is the only marker that makes sense, but it is not universal to all locales. The best solution is to omit them completely from websites with an international audience, although I suppose as a second-best solution I would accept commas as slashdot is run by people in and hosted in the USA.

        • The apostrophe doesn't denote minutes; the prime symbol does. And as to whether the comma "makes sense", I've always found it peculiar that people in the US prefer to make the most important separator the least conspicuous one. To me the exact opposite would "make sense".

  • Unit economics? (Score:5, Interesting)

    by memory_register ( 6248354 ) on Friday September 17, 2021 @08:12AM (#61804139)
    The process all sounds well and good, but if their synthetic fuels are 10x the price of oil, this will not make a lick of difference. I will wait until they share some actual cost data; generally when that sort of math is not shared, it means the idea is (currently) too expensive to matter.
    • Umm, it is very early in this research. Give them a little time. Hydrocarbons are fantastic energy storage liquids. Think of them as batteries without a body.

      • Battery tech isn't going to stand still either, though. In the end, what will really matter is if the process has less energy loss than the battery based equivalent.

        • It's not just about efficiency, airplanes in particular can't get around the issue of density. (Both energy per-mass and per-volume).

        • >what will really matter is if the process has less energy loss than the battery based equivalent

          Well, that and...
          - The price per kWh of storage - liquid fuels are GREAT at that, since storage is essentially just an unpressurized tank.
          - The energy density - which is especially relevant for long-range transportation uses. And where hydrocarbons are about 50x better than the best batteries, with no significant battery improvements on the horizon.

          There's plenty of situations where storing energy as synthet

    • Every idea starts as too expensive. Renewables were unaffordable for years, until they actually got cheaper, and that's of course assuming we continue to subsidize fossil fuels, and we allow everyone gathering and selling fuels to write off climate change as "not their problem", and letting the hurricane, wildfire drought etc.. victims and tax payers be the ones to take the costs from climate change.

    • Re:Unit economics? (Score:5, Interesting)

      by slack_justyb ( 862874 ) on Friday September 17, 2021 @08:45AM (#61804257)

      Well take this [priceofoil.org] (but with a grain of salt because of who wrote the report) report and it indicates that subsidies for oil are a rate of about 7 to 1. If this process can reach of a price of 5x oil, then it's got enough margin to become competitive with oil should those subsidies end. Which I think given the current climate about climate change, ending oil subsidies might be on some people's radar. Maybe not tomorrow, but I'm thinking it is becoming a slightly more real proposition that we may see sometime in the future governments just simply stop investing so heavily in oil. Oil has become a bit of a sticky topic and the whole fighting for it, sending tax dollars into it, and the sometimes having to clean it up.. Well I think it is fair to say that some people aren't seeing it as the "good trade" as it once was. Solar to fuel is going to have it's share of clean up issues and what not, but I believe that the "trade" for the "issues to fuel" that come with it are reaching a more palpable state in the public's mind.

      You're right that it does come down to cost on these kinds of things and these kinds of processes that turn solar into fuel are not there yet. But it is also important to remember that the price of oil we see is heavily subsidized and that the true cost of oil is a lot higher and thus if we subsidize these kinds of processes at the same rate, then they can "hypothetically" become as cheap as oil, at least to the consumer.

      The over arching thing here is, cost is a complex topic, because the true cost of things gets hidden from consumers by government intervention. So if we are going to talk cost of A versus cost of B, inevitably we have to bring up subsidies. But not to distract from your point, you've got a correct point. Cost is very important for people for fuels.

      • Re: (Score:2, Informative)

        by RemindMeLater ( 7146661 )
        Ugh.. about 120 million barrels of oil are used per day. Currently $71/barrel. So that's $8.5 billion being spent on oil per day. Your link is alleging that governments are subsidizing oil to the tune of nearly $60B/day or $21 trillion per year. That seems very unlikely.

        The fact remains that oil -- coming free out of the ground -- is the very lifeblood of our civilization. Nothing else comes close. Renewables aren't even keeping up with new energy demand growth.

        • Your link is alleging that governments are subsidizing oil to the tune of nearly $60B/day or $21 trillion per year. That seems very unlikely.

          Have you seen the US military budget, or heard about our awesome Middle Eastern Adventures (tm)?

        • Not sure about OP's sources, but one thing to keep in mind is that not all subsidies are in the form of payments to the recipient. Alternate subsidies include:

          - Industry-specific tax breaks: those "cost" the government a massive amount in lost revenue that any other industry of the same size would be paying.

          - waivers permitting/lack of regulations prohibiting damage to the commons (e.g. via pollution, deforestation, or anything else that harms an asset benefiting the common welfare) Every dollar of enviro

        • That seems very unlikely.

          Like I said, take with grain of salt.

          The fact remains that oil -- coming free out of the ground

          Hold up now. Have you seen the lengths we need to go to, to get aforementioned "coming free out of the ground" resource? You can say the paper is presenting hyperbole. But once you also start doing it, it kind of ruins your argument.

          Nothing else comes close. Renewables aren't even keeping up with new energy demand growth.

          You're right, but at the same time, we're not even working renewables at the rate we work oil. People in the 90s had zero issues tossing tens of billions down on oil projects. We're not even close to that kind of investment in renewables

        • Re: (Score:2)

          by ceoyoyo ( 59147 )

          There's nothing free about getting oil out of the ground. In some places it is fairly cheap, but those places are hell holes. In other places it's quite expensive, and it's debatable whether the result produces more energy than it requires to dig it up and deliver it.

      • Re: (Score:2)

        by e3m4n ( 947977 )
        the thing to remember, also, is that this is not green energy, despite the articles claim. At best its neutral energy, which is a distinction. It is certainly better than release long-term-captured carbon, but it is still re-releasing carbon back into the atmosphere. We are now at a point where we need to start doing some long-term-capture ourselves. Another thing I see missing from a lot of discussion is the stored energy in the ocean temperatures.

        One of the biggest concerns about rising global temps is

        • Re: (Score:2)

          by ceoyoyo ( 59147 )

          According to your definition, solar, wind, hydro, geothermal, etc. are not green either. They're "merely" neutral.

          Ending net carbon release into the atmosphere, particularly for something like aviation where we don't have a realistic alternative to carbon based fuels, is a big deal.

          There's not a whole lot of point in carbon capture while we're still digging the stuff up and burning it. It's like bailing out a boat with a teaspoon while there's a big hole in the bottom.

          • If we stopped burning all long term carbon, right now, no more ever, only neutral sources, it would not be enough to reverse the levels we have. For some duration of time we need to be net negative, not neutral, not net positive.

            Btw, wind, solar, nuclear, are primarily green because they do not produce or release carbon, even short term carbon recently captured. I agree this is a big deal for some applications. I also think if they create synthetics using OTEC turbines its effect will be even more signif

      • Those people play fast and loose with the definition of "subsidy."

        A profitable industry pays taxes to the U.S. Treasury (for example: Exxon sent $9.53 billion to the Treasury in 2018), but when dealing with a subsidized industry, money flows in the other direction.

        An example of a truly subsidized industry is Amtrak. About $2 billion every year is transferred from the U.S. Treasury to Amtrak so it can continue to operate. That is on top of state subsidies. 17 state legislatures transferred a total of $234

        • Re: (Score:2)

          by MrL0G1C ( 867445 )

          $2 billion is peanuts compared to the $141 billion the US spends on roads annually. Oil's subsidies come in the form of tax breaks, money does not have to flow in the other direction for a subsidy to be in effect,

    • Re: (Score:2)

      by larwe ( 858929 )

      The process all sounds well and good, but if their synthetic fuels are 10x the price of oil, this will not make a lick of difference

      Remember, there's two ways to fix that - either make their fuels 10x cheaper, or tax fossil fuels to be 10x more expensive. If the technology is scalable and offers an immediate step change in net emissions, it is conceivable that governments could mandate it, at least as an additive, the way ethanol is mandated right now. What I'm more interested in, theoretically of course, is how compatible these fuels are with standard dinosaur juice - both from the "can you use it as an additive or does it have to be p

    • Re: (Score:2)

      by Rhipf ( 525263 )

      Right from the summary:

      The company states that through this technology, it can provide fuels at a cheaper price with a 50 to 100 percent lower carbon footprint compared to fossil fuels

      So if they can actually produce the synth fuel "at a cheaper price... compared to fossil fuels" I doubt that you will need to pay "10x the price of oil" unless someone is taking excessive profits.

      • Re: (Score:2)

        by larwe ( 858929 )

        So if they can actually produce the synth fuel "at a cheaper price."

        This is the piece I don't trust as it's unproven. The cost may be an acceptable cost for the net environmental benefit, I can't really speculate on that. I am simply going through various stages of belief here: 1) believing that it can be done, 2) believing that it can be done at scale, 3) believing that it can be done at scale and cost effectively. I don't understand the chemistry involved here but I wonder if it produces sufficiently long-chain hydrocarbons that it would be compatible with existing refine

        • Re: (Score:2)

          by Rhipf ( 525263 )

          Since they are building the hydrocarbons from H2O and CO2 they could theoretically by pass the refining process and just produce gasoline (or propane or whatever) directly.

    • Since the raw materials are nearly universally available, the entire cost is probably in producing and maintaining the equipment. Something that is expensive now could be much cheaper when you factor in economy of scale.

  • I fully expect this will be a more complicated version of corn ethanol - where "green" fuel is nothing but oil-based fuel spent elsewhere in the production chain.

    • >"I fully expect this will be a more complicated version of corn ethanol - where "green" fuel is nothing but oil-based fuel spent elsewhere in the production chain."

      Case in point, the article says nothing about where they are obtaining the CO2 they are using in this process. How was it obtained? What was used to produce it? How much energy did that take to create/transport?

      It also doesn't give any hints as to quantity. It might be neat, but if a huge plant produces only a few thousand gallons a day,

      • They are hinting at it: they mention a 50-100% lower carbon footprint compared to fossil fuels. The difference is the energy required to build, maintain and run the facility (not much) and getting the H2O and CO2 for the process. So it's close to 100% if you have some means to get CO2 using nothing but solar power.

      • Re: (Score:2)

        by HiThere ( 15173 )

        There are LOTS of sources for CO2. I don't think extracting it from the atmosphere would be cost effective, though. But final costs are a real problem. They seem quite optimistic, but this is a PR release.

      • Re: (Score:2)

        by larwe ( 858929 )

        Case in point, the article says nothing about where they are obtaining the CO2 they are using in this process

        It's almost not relevant to this early research, but in fact the obvious place to source large amounts of concentrated CO2 is from sequestration projects. Your power plant pumps out CO2 as it burns MagicFuel(tm) (or oil). Instead of pumping that into a cave somewhere, you push it off to the reconverter array. In theory this could be colocated with the power plant (but doesn't need to be - you can transport it in a pipeline or with trucks that are also powered by MagicFuel(tm)). So it basically converts oil

        • Re: (Score:2)

          by Rhipf ( 525263 )

          without the cost and physical/environmental footprint of battery storage.

          Wouldn't your power plant be bigger and probably more expensive than a battery storage unit?* From what I have seen the Tesla mega-battery units aren't all that huge and most (all?) gas/oil/coal power plants I have seen are quite huge.

          • Re: (Score:2)

            by larwe ( 858929 )

            Wouldn't your power plant be bigger and probably more expensive than a battery storage unit?* From what I have seen the Tesla mega-battery units aren't all that huge and most (all?) gas/oil/coal power plants I have seen are quite huge.

            I was assuming that the power generation plant itself already exists (along with at least some onsite storage for liquid or gaseous fuel reserves), and that we're just talking about the incremental footprint of the converter thingy. But even so I'm pretty sure - without looking up any numbers - that a week's generation feedstock in oil occupies a lot less volume than the equivalent wall of batteries. Not to mention it doesn't self-discharge.

    • Re: (Score:3)

      by nickovs ( 115935 )
      Corn ethanol does provide some incremental improvement over fossil fuels, since a significant part of the energy comes from the sunshine that grew the corn, but it was never a great solution. That said, it had two significant things going for it: the chemical processes used were well understood and mature and it was easy to sell the idea to voters in the mid-West of the USA. The solution here is quite different. Using a catalyst to reverse normal combustion process O2 + CnHn -> CO2 + H2O + heat, so that

      • Re: (Score:2)

        by sinij ( 911942 )

        Corn ethanol does provide some incremental improvement over fossil fuels, since a significant part of the energy comes from the sunshine that grew the corn

        Citation required to substantiate claim that 'significant' part of the ethanol derived from corn comes from sunshine. I suspect such accounting forgetting to account for fertilizer, farm equipment used to plant and harvest, transportation of corn and only starting to account from 'already there' corn in 'already there' plant to come up with a break-even numbers.

        • Re: (Score:3)

          by nickovs ( 115935 )
          Happy to provide citations. Ethanol already had a Net Energy Value around 1.3 way back in 2002 according to the US Department of Agriculture [energy.gov], taking into account fertiliser, mechanical farming, inputs into the conversion process and transportation, and they noted at the time that efficiency has been rising steadily as processes improve. A survey of more recent studies [ethanolproducer.com] from 2016 showed average NEVs of between 1.52 and 1.73 with the best producers getting 2.27 without considering the useful energy that can
    • I can't speak to the larger supply of ethanol but the I'm from corn country. The farm vehicles are universally adapted to run on ethanol there and the ethanol is made from husks and other waste plant material and the actual corn ends up sold or used to feed livestock.

      • Re: (Score:2)

        by larwe ( 858929 )

        I can't speak to the larger supply of ethanol but the I'm from corn country.

        Me too (SW IN represent!), though not a farmer. My understanding is that the ethanol from waste plant fiber products (cellulosic ethanol) is more expensive to produce, due to lower yields per ton of feedstock. The ethanol that's used in gasoline is made from the sugars in the corn itself, and one side effect of that is that it competes directly with corn sold for food. (Yes I know the cattle feed grades of corn are not used for human food, but the fact remains that ethanol production affects food pricing ht [epa.gov]

        • Central Illinois here, maybe 1 1/2hr down the road from Terre Haute.

          It's just an anecdote (a 25yrs dated one at that) but pretty much every farm I'm aware of actually uses a bit of both, with most of the material being the fiber products and a certain amount of corn added to top up the sugar content. But to my knowledge none of them weren't actually selling ethanol. They just produced it to use on the farm and, since most of them didn't actually denature it, to give their kids nasty hangovers.

          • Re: (Score:2)

            by larwe ( 858929 )

            But to my knowledge none of them weren't actually selling ethanol. They just produced it to use on the farm and, since most of them didn't actually denature it, to give their kids nasty hangovers.

            Right, this is just a "use everything but the squeal" philosophy. If you can cut down your fuel purchases by turning some of your unsaleable plant product into burnable fuel, you do it. I always wondered if the ATF actually came to inspect registered ethanol fuel stills, since the denaturing thing is little more than a pinky swear otherwise :)

      • ...to run on ethanol there and the ethanol is made from husks and other waste plant material and the actual corn ends up sold or used to feed livestock.

        Really? That's the first I've ever heard of commercial scale ethanol from cellulose. Way back in 2000, when fuel ethanol was taking off, that was always the plan: use corn (kernels, the bit something might eat) as a way to bootstrap the industry. While that was spooling up, develop a way to ferment cellulose. A commonly listed feedstock was going to be switchgrass because it's easy to grow on land which isn't suitable for crops.

        My understanding is no one ever actually developed a way to ferment cellulose.

  • The problem with concentrating solar solutions (Score:5, Informative)

    by K. S. Kyosuke ( 729550 ) on Friday September 17, 2021 @08:21AM (#61804161)
    The problem with concentrating solar solutions remains: they only work reasonably well in areas with very low cloud cover. If you get *any* clouds, they get beaten by flat PV panel solutions. That limits them geographically in a significant wat, whereas just connecting large areas of a country using a grid and feeding a chemical plant with electricity is something you can do pretty much anywhere. So while thermodynamically the "directly heated" high-temperature solutions like this one make sense for fuel synthesis, the logistics of moving massive amounts of fuels across the Earth will still be here.

    • Re: (Score:2)

      by HiThere ( 15173 )

      This isn't generating electricity, this is process heat. For that solar cell->electricity->heat is much less efficient than just solar radiation->heat. It won't work well on cloudy days, but the idea is to produce fuel, so it could be set up in the Sahara desert, or on the Arabian peninsula, or the Kalahari, or the Mohave, or ... well, there are lots of places around the world. We've got a lot of experience in storing and moving hydrocarbon fuels.

      • Could be a solar pond as much as a mirror, and less fragile. But deserts already have different uses like food [youtu.be], or just altering them [youtu.be] in general which could effect climate.

      • This isn't generating electricity, this is process heat

        Read again; I didn't say anything about this being *generating* electricity. This is about synthetic petrochemicals, of course.

        For that solar cell->electricity->heat is much less efficient than just solar radiation->heat.

        The alternative path to hydrolysis is electrolytic, not thermal, so you would never use the same plant, only heated by electricity. Your alternative is an electrochemical plant of a different design.

        • Re: (Score:2)

          by HiThere ( 15173 )

          Well, if you change that much, I can't compare them. There would probably be LOTS of different tradeoffs that I've got no idea about.

          • The point was that in most regions of the world, there's no comparison necessary; the concentrating plant just won't work ~90% of any year.

            • Re: (Score:2)

              by HiThere ( 15173 )

              But because it's manufacturing hydrocarbon fuel, it doesn't need to be located in every corner of the world, only in a few places where it would work optimally.

              It's not as if it's competing against electric generation. Hydrocarbon fuels will continue to be nearly optimal for several mobile purposes. Airplanes don't really have a decent alternative to pick one example.

              • But because it's manufacturing hydrocarbon fuel, it doesn't need to be located in every corner of the world, only in a few places where it would work optimally.

                Those "optimal places" may not necessarily be the places Europe wants to politically or economically depend on.

                It's not as if it's competing against electric generation. Hydrocarbon fuels will continue to be nearly optimal for several mobile purposes. Airplanes don't really have a decent alternative to pick one example.

                But I've never said they won't continue to be nearly optimal for these purposes. Of course you'll need hydrocarbons for many things.

    • Re: (Score:2)

      by Rhipf ( 525263 )

      the logistics of moving massive amounts of fuels across the Earth will still be here.

      I guess we should have spent the last 100+ years figuring out this problems so that we would have a system in place by the time this solar synth fuel production becomes practical. 8^)

    • I doubt it can compete long term with PV. Heliostats have a much higher minimum requirement of materials per m2 than PV IMO.

      When PV gets really cheap is when it stops being mounted on steel construction and simply rolled out onto the soil.

    • Re: (Score:2)

      by AmiMoJo ( 196126 )

      It's not like oil is available just anywhere either.

      • True, but why wouldn't you at least try a solution that removes a part of the need for bulk global shipping? (And the occasional environmental disaster when a tanker with 500kt of oil sinks...)

    • The problem with concentrating solar solutions remains: they only work reasonably well in areas with very low cloud cover.

      This does not have to be a continuous process. You can make syngas on sunny days, and store it to use later, when it is not sunny.

      So while thermodynamically the "directly heated" high-temperature solutions like this one make sense for fuel synthesis, the logistics of moving massive amounts of fuels across the Earth will still be here.

      I would have thought moving massive amounts of fuels across the Earth is something we know how to do quite effectively. We have tankers and pipelines. The infrastructure is already there.

      • This does not have to be a continuous process. You can make syngas on sunny days, and store it to use later, when it is not sunny.

        You can do that with PV as well, and perhaps even better given the load curves. Furthermore, in winter, you can do the same thing on windy days instead. Certainly in Switzerland and its surroundings, this will work better then concentrating solar, especially in winter.

        I would have thought moving massive amounts of fuels across the Earth is something we know how to do quite effectively. We have tankers and pipelines. The infrastructure is already there.

        Yes, and the you have to send aircraft carrier groups into the Persian Gulf every decade or so, and deal with tankers sinking (and polluting the environment) every now and then as well.

  • Could they add a bit more marketing speech? I don't think it was enough to incentivize the potential VCs here in the Slashdot crowd.

  • Does it pass the smell test? (Score:5, Insightful)

    by 140Mandak262Jamuna ( 970587 ) on Friday September 17, 2021 @09:12AM (#61804361) Journal
    Often fossil fuel companies fund these "research" for the purposes of grabbing tax incentives meant for renewables and to create PR and spin doctoring.

    So first we dig through to see if there is any coal/natural gas involved. At the first glance it does not seem to be so. A simple thermal solar plant uses the same field of heliostats to concentrate solar radiation in the form of heat. Typically they get hot enough to melt salt but not higher. Here by making the collector gas, adding the same green house gases it raises the temperature to 1500 C. Need to make sure, the decimal points in the summary are confusing.

    After raising the temperature to 1500 degree, there is a missing step, seen many times in slashdot. 1 Something. 2 Something Else. 3 ... 4 Profit?.

    Heat alone does not create any synthetic fuel. Electrolysis does. Photosynthesis does. Not plain heat. Plain heat, higher temperature improves the efficiency of heat engines. Thus it can be a simple efficiency improver for solar thermal powerplant producing electricity.

    Its true electricity can make synthetic fuels. But PV panels make electricity directly. So why this?

    In summary good thing: It does not seem to be FF created FUD, misdirection or cash grab.

    Probable: Some overhyping of something to fuddle duddle angel investors and venture capitalists looking for the next unicorn. Got to check mark every buzzword people of grepping for. Synthetic fuel is one of them. Looks like.

    • Iâ(TM)m a little curious as to how they get to fuel from hot soda water myself.

    • A quick Google search says that a Ni or Cu catalyst could help with splitting H2O and create preferential conditions for bonding that H2 with the carbon. Usually people leave the secret sauce out of their press releases until the ink on the patent is dry. Gives less time for another company to swoop in and construct a parallel method that avoids the patent.

      • Hope you are right.

        Heliostats to concentrate solar thermal radiation.

        Runaway green house due to water vapor and CO2

        1500 C.

        Catalyst break H2O and creates CxHy and O

        Best of luck to them. Hope they succeed. There are applications where only liquid fuels have the required energy density. Sea, air and heavy duty trucking. So a clean green synthetic fuel machine would be nice.

    • Heat alone does not create any synthetic fuel. Electrolysis does.

      How about coal gas [wikipedia.org]?
      C (s) + H2O (g) -> CO + H2 (endothermic water gas reaction)

      One of the complaints about "green" hydrogen fuel cell technology is that the above process is far from carbon neutral. Electrolysis of water, using electricity from renewable resources, would be a preferred way of making "clean" hydrogen fuel, but I think the old water gas process is still the main industrial process.

      I am not sure how CO2 reacts with H2O to create hydrocarbons. Water is fiercely reactive at high temperature. T

    • What they are doing sounds pretty similar to the Fischer-Tropsch process [wikipedia.org] -- which requires thermal energy (heat) as an input, not electrical energy.

      But I do not appreciate the hyped way the summary was written ("The system is quite genius").

  • Okay, so I left a bottle of Coke in the sun all day. Do I put it in my gas tank now?
  • The biggest advantage liquid fuel has is energy density. Up to this point, for any transportation sector, road, non-electrified rail, sea or air, there simply was no alternative.

    Battery electric cars are now competitive at some price range but not all. But the trend is clear, in 10 years BEVs will be cheaper, and given the other advantages lots of people would switch. Enough to reduce the economy of scale of gasoline production and distribution. Gasoline will get into vicious cycle (loss of economy of sca

    • Tricking startup investors. Saying synthetic fuel probably translates to light alcohols see https://en.wikipedia.org/wiki/... [wikipedia.org], then lengthing the chain - something that costs - which is why ethanol is not upgraded or converted. The most efficient use of solar array heat, is to make cement. The cheapest fuel product comes from burning waste. Second most cost effective is re-refining waste oil, be it car oil or chip oil. Then Brazil and sugars to ethanol, powered by natural sunlight. Not far behind is using

    • we can put overhead electric cable over a 30 mile stretch of a highway and trucks going at 60 mph can use pantographs like electric train and pick up enough juice to go another 200 miles in 30 minutes/miles

      That's impressive, I would have though that much current with that much speed and vibration, there would be crazy friction and arcing and the electrodes would be worn down in no time.

      • Seen bullet trains? or TGV? They transmit enough power to haul a trainset above 200 mph. We are talking just 60 mph here.

        Dont imagine a bumpy road surface with worn down by heavy trucks and heavy braking. This lane with overhead line will be super smooth concrete, trucks running on cruise.

        Of course there are issues, not easily solved, that's why we don't see much talk about them. Even small cars want to charge at 128 kW or 256 kW at super chargers. Trucks would like to charge at a minimum of 1 MW. How m

    • The biggest advantage liquid fuel has is energy density. Up to this point, for any transportation sector, road, non-electrified rail, sea or air, there simply was no alternative.

      Battery electric cars are now competitive at some price range but not all. But the trend is clear, in 10 years BEVs will be cheaper, and given the other advantages lots of people would switch.

      That seems optimistic. Last I heard, liquid fuels still have something like 10x the energy density of batteries (although I don't know what happens when you factor in the weight of the engine and motors).

      People have been beavering away at making more energy dense batteries which recharge faster for years and as far as I can tell, the state of the art has barely budged. Cost has improved, to be sure, but not energy density or recharge rate.

      • Model 3 long range weight: 4250 pounds
        Model 3 stated range: 315 miles

        BMW 340i weight: 3684 pounds
        BMW 340i range: 395 miles

        Yes, batteries are heavy, but more-or-less offset by the weight of a big engine, transmission, gas tank, drive shaft, differentials, exhaust etc. Remember that while liquid fuel might be more energy dense, the combustion engine itself is not at all efficient at extracting that energy because heat is a waste product - somewhere around 20% efficiency.

        Burning that same fuel in a thermal po

  • As seen on TV (Score:3)

    by RogueWarrior65 ( 678876 ) on Friday September 17, 2021 @10:57AM (#61804677)

    https://youtu.be/Mb_8DJF6Hp0 [youtu.be]

  • In my physics course we called that "sunlight". Who wrote this crap?

    The technology is interesting though.

  • I joke. I joke... kind of. After all that transformation, what kind of net are we getting? And a thermochemical reactor is needed? Are we getting more out of this than we would out of the reactor heating up organic gunk and making that into hydrocarbon fuel? Or shooting the power into batteries?

    So, color me skeptical.

    • And a thermochemical reactor is needed? Are we getting more out of this than we would out of the reactor heating up organic gunk and making that into hydrocarbon fuel?

      Why not forget about a thermochemical reactor at the temperature of molten steel, and just go with the organic gunk? The biochemistry works at normal ambient temperature. The chemistry is bloody unlikely, but it works. You take two stable chemicals, carbon dioxide and water, add some enzymes and sunlight, and get useful carbohydrate fuel, plus highly useful oxygen as a by-product. It took ages for chemists to learn how to extract oxygen by artificial means, because it is so reactive that it grabs onto almos

  • It seems like a much better end use of this sort of technology would be to replace the use of fossil fuel in large scale processes. The production of fertilizers and cement together use more than 15% of all our energy. They also require some unit ops at greatly elevated temperatures (and pressure for the Haber process), and can largely be situated in locations that would be good sources for solar power.

  • nuclear (Score:3)

    by backslashdot ( 95548 ) on Friday September 17, 2021 @03:21PM (#61805399)

    Nuclear is the best way to do this, if only it didn't trigger hysteria in the ignorant masses.

  • I can't help but wonder how many birds are going to get roasted when they fly into the zone of concentrated sunlight near the collection tower. This has been an issue with other solar concentration projects [sciencealert.com].

    And don't get me going about windmills ...

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