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Power

Redox-Flow Cell Stores Renewable Energy As Hydrogen (ieee.org) 75

An anonymous reader quotes a report from IEEE Spectrum: Hydrogen is a very good carrier for this type of work," says Wei Wang, who is the chief scientist for stationary energy storage research at the Pacific Northwest National Laboratory in Washington. It's an efficient energy carrier, and can be easily stored in pressurized tanks. When needed, the gas can then be converted back into electrical energy via a fuel cell and fed into the grid. But water electrolyzers are expensive. They work under acidic conditions which require corrosion-resistant metal plates and catalysts made from precious metals such as titanium, platinum, and iridium. "Also, the oxygen electrode isn't very efficient," says Kathy Ayers, vice-president of R&D at Nel Hydrogen, an Oslo-based company that specializes in hydrogen production and storage. "You lose about 0.3 volts just from the fact that you're trying to convert water to oxygen or vice versa," she says. Splitting a water molecule requires 1.23 V of energy.

In a bid to overcome this problem, Nel Hydrogen and Wang's team at Pacific Northwest joined forces in 2016, after receiving funding from the U.S. Department of Energy's Advanced Research Projects Agency-Energy. The solution they've come up with is a fuel cell that acts as both a battery and hydrogen generator. "We call it a redox-flow cell because it's a hybrid between a redox-flow battery and a water electrolyzer," explains Wang. A redox-flow battery, in essence a reversible fuel cell, is typically made up of a positive and negative electrolyte stored in two separate tanks. When the liquids are pumped into the battery cell stack situated between the tanks, a redox reaction occurs, and generates electricity at the battery's electrodes.
Compared to normal flow batteries, the new redox-flow cell exhibited a charge capacity of up to one ampere per square centimeter, a ten-fold increase. "It was also able to withstand 'several hundred cycles' of charging, which has never been demonstrated before in hydrogen ion flow batteries," the report says.
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Redox-Flow Cell Stores Renewable Energy As Hydrogen

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  • As usual, the risky basic research is being done at public expense, and the safe investment is made by the private company to keep the majority of profits for themselves.

    And we wonder why a growing percentage of Americans live in poverty.

    • Re: (Score:1, Offtopic)

      by blindseer ( 891256 )

      As usual, the risky basic research is being done at public expense, and the safe investment is made by the private company to keep the majority of profits for themselves.

      And we wonder why a growing percentage of Americans live in poverty.

      I heard a clip out of a standup routine by, if I recall correctly, Norm Macdonald about the hypocrisy people feel about "big business". In this clip the observation was made that "big pharma" is evil until they come along to save your life. "You say this costs $200 per pill? Okay, I'll take all you have."

      Nobody trades down. "Big oil" isn't stealing from anyone because people willingly trade their dollars for the fuel that will allow them to get to work, school, a hospital, get food, or whatever. The go

      • Illegal immigrants tend to bring...disease.

        You're going to need a citation on that one. For example, last time I checked, New York and Washington had more cases of measles than Mexico did.

        • You're going to need a citation on that one. For example, last time I checked, New York and Washington had more cases of measles than Mexico did.

          You think that maybe there's fewer cases of measles in Mexico because the people with measles come to the USA for treatment?

          Where have you been for the last three months that you need a citation? Have you not seen the news? Just to show I'm not blowing you off I'll give a citation.
          https://thehill.com/opinion/im... [thehill.com]

          Undocumented aliens would be wise to stay out of the United States.

          I just thought I'd grab that line out of the article for emphasis. You hear that illegal aliens? America is a bad place. We are full of disease. There's no work here. People are racist, sex

          • You think that maybe there's fewer cases of measles in Mexico because the people with measles come to the USA for treatment?

            No, I think there are fewer cases of measles in Mexico because they get vaccinated.

            • Most school districts in the US force children to be vaccinated for MMR before they are allowed to be enrolled in any school.
              • And yet you have to admit we've had measles resurgences because people don't vaccinate their kids, for various reasons.
            • No, I think there are fewer cases of measles in Mexico because they get vaccinated.

              Vaccinations are not 100%. I say we build a wall to keep out those trying to get into the USA illegally to keep them from getting infected.

              Again to all those thinking of coming to the USA illegally, the USA is full of infected people. If you come here you run the risk of catching something very bad. In fact you should all be building walls to keep Americans out. Because Americans have measles.

              • by Layzej ( 1976930 )

                the USA is full of infected people. If you come here you run the risk of catching something very bad

                That is true. Before we closed the border with the USA, 70% of Canadian infections were from people who had visited the USA. The problem in the USA was becoming apparent to Canadians before it was obvious to Americans.

              • I asked you for a citation, you didn't give me one. You gave a citation to something unrelated.

                Either prove that illegals are bringing diseases into the US, or admit you were wrong. You have no other choice.
                • Either prove that illegals are bringing diseases into the US, or admit you were wrong. You have no other choice.

                  Of course I have another choice. I can call you an ignorant ass.

            • I think there are fewer cases of measles in Mexico because they get vaccinated.

              Measles vaccination rate in Mexico: 97%
              Measles vaccination rate in America: 92%

              Measles vaccination rates by country [worldbank.org]

              • by gweihir ( 88907 )

                I think there are fewer cases of measles in Mexico because they get vaccinated.

                Measles vaccination rate in Mexico: 97%
                Measles vaccination rate in America: 92%

                Measles vaccination rates by country [worldbank.org]

                And: Level needed for herd-immunity: 97%. The US rate of 92% is far too low.

            • by gweihir ( 88907 )

              You think that maybe there's fewer cases of measles in Mexico because the people with measles come to the USA for treatment?

              No, I think there are fewer cases of measles in Mexico because they get vaccinated.

              Indeed. Poor people in poor societies tend to understand that vaccinations save lives and when they can get them, they do.

              • by Layzej ( 1976930 )
                Plus Mexico has public health insurance. The shots are free. In the USA they can cost up to $652.
          • in Mexico because the people with measles come to the USA for treatment?
            Pople living in Mexico, so poor that they can not afford the vaccine, most certainly can not afford any treatment in the USA ...

            • by gweihir ( 88907 )

              in Mexico because the people with measles come to the USA for treatment?
              Pople living in Mexico, so poor that they can not afford the vaccine, most certainly can not afford any treatment in the USA ...

              Indeed. They can most certainly not afford US health-care. The very idea is utterly disconnected from reality. The very idea shows a lot about the person suggesting it, but not about reality.

      • by cusco ( 717999 )

        I remember hearing a story of how the government needed tanks for WW2

        Yeah, it's just a story, probably made up by the Libertardians. Profit has always been the reason for selling war materials ever since the weapons were made of stone. General Smedley Butler wrote 'War is a Racket' in 1935, well before your phantasmagorical tanks. I highly recommend it.
        https://ratical.org/ratville/C... [ratical.org]

        Of course, it isn't put that crudely in war time. It is dressed into speeches about patriotism, love of country, and "we must all put our shoulders to the wheel," but the profit

        • by blindseer ( 891256 ) <blindseer.earthlink@net> on Tuesday April 14, 2020 @02:04AM (#59944144)

          I'm sorry, did you have a point? Of course their profits went up. That's what happens when production goes up.

          I remember when Hilary Clinton made a big point on how she wanted to raise taxes on those eeeeevil oil companies because they made too much money from gasoline sales. The smart people pointed out that this didn't punish them, they just passed that cost onto consumers.

          Then the Democrats wanted a "windfall tax" on the oil companies because they made "too much" money. But when it actually came to putting this into law they could not decide on how much was too much. No matter what they specified as "enough" profit the oil companies could simply manage their costs to stay under it and the government would get nothing.

          But these big companies are greedy? Is that it? Well, aren't you greedy for expecting them to produce products for you for no profit? Aren't you profiting from their work then? Again, nobody trades down. When you give dollars for gasoline then you profit off that. The people that drilled for the oil, refined it, and brought it too you, all want some of the profit. What gives you the right to take more than your fair share in this?

          But no, these people are bad. They only profit off of government research by selling the drugs developed with your tax dollars. Well, there's a cost for the research which we all benefit from in some way or another with fewer people sick or dead. There's a different cost in producing the actual medications, and that needs to be paid for. If there's no profit in selling these life saving drugs then maybe they will just go into drugs where there is more profit. Like perhaps ED treatments, birth control, vitamin supplements, and whatever that the wealthy are willing to pay for.

          Claiming someone makes "too much" money is just greed and jealousy. Using the government to take this is just legalized theft.

          • by cusco ( 717999 )

            Hilary Clinton? Whose husband sent US troops to Colombia to guard Occidental's oil pipeline for no charge? Sorry, but [Citation Needed]

            Since you want to be obtuse the point was that your cute little anecdote about the tanks was BS, as is your economic theory.

      • You say this costs $200 per pill when last month they were only 20 cents, but now you've bought the patents? Okay, I'll take all you have because I will die otherwise

        FTFY. Big business in itself isn't evil, at best it is amoral. And making profit is fine. Even so, individual execs in big business often do some pretty evil things in order to increase their profits.

        In this case, GP's point is that this private company isn't funding the research, that risk is assumed by the public. The patent and profits however go to the private company. I couldn't glean from TFA if that's true, but it is often the case in partnerships like these.

    • What incentive is there for people to move out of poverty when they receive money from the government for food, utilities, housing, medical costs, child care for being poor?
      • oh gawd, that ignorant generalised old idea is still being spouted.
      • You answered your own question. Those being given money are still in poverty. I guess you're a privilaged white arsehole who has never been in poverty before, it's really the only way someone can come up with the throught you just had.

    • The poverty rate has been falling [census.gov]. Makes the rest of your statement kind of hard to consider as a rational statement...
    • Once we as a society decided that we should outsource as much production overseas as possible, because you know, profits and efficiency the ball was set in motion. (After all, factory work is so easy, anyone could do it. Why should they make a princely wage when a chinaman will do it for pennies on the dollar? Besides I live in a nice suburb, the poors and browns can just fend for themselves.)

      Having consumers use price as the ONLY metric just finished the job. Once that inevitable race to the bottom was s

    • As usual, the risky basic research is being done at public expense, and the safe investment is made by the private company to keep the majority of profits for themselves.

      And we wonder why a growing percentage of Americans live in poverty.

      We Privatize the Profits and Socialize the Losses - Losses Such as the Cost of Research.
      Former Secretary of Labor Robert Reich said America is a hotbed for socialism, but for the rich and not the poor. "It's socialism for the rich. Everyone else is treated to harsh capitalism."
      In the 2007-2010 Great Recession, the government subsidized weak and failing firms, and the taxpayer pays the tab. It's called "Lemon Socialism." https://en.wikipedia.org/wiki/Lemon_socialism [wikipedia.org]

      Fair Warning: the following is what

      • Isn't rampant consumption the problem not the consequence?
        • Isn't rampant consumption the problem not the consequence?

          Depends.
          The problem now is a pandemic, and our responses to it have had the consequence of spurring a rampant worldwide financial crisis, massive unemployment, hunger, and homelessness.

    • As usual, the risky basic research is being done at public expense, and the safe investment is made by the private company to keep the majority of profits for themselves.

      The public reward is having new products like this invented and brought to market, so they can purchase it if they feel it will help their work and lives.

      When you buy a product, you're doing so because you will profit from it (if it was a good purchase). e.g. A carpenter who decides to buy a hammer does so because he can use it to make

    • And we wonder why a growing percentage of Americans live in poverty.

      Only those of us who can't be bothered to do a quick google query.

      Those of us who do the google query notice that while poverty rates vary year to year, they're about half what they were back when I was a kid. And that's with a definition of poverty that's changed several times since I was a kid...

  • What is becoming finally clear, is that there are two recharge able battery markets. The fixed energy store, one that does not, that can be heavy and large and number of efficient energy charges and discharges is the most important. This versus the mobile market, where the battery moves, where compactness and light weight have to take priority.

    Renewable energy is about to get a major boost as more focus shifts from mobile rechargeable batteries to fixed in place batteries. Both of course mean, fossil fuels

    • Renewable energy is about to get a major boost as more focus shifts from mobile rechargeable batteries to fixed in place batteries.

      No, they won't.

      Batteries that can be used to fill in for intermittent energy can also be used for large steam based power plants to follow load. In both cases the solution for now is the use of natural gas single cycle turbines. These can be brought on line quickly but they burn twice the fuel for the same electricity as combined cycle turbines. But combined cycle turbines use steam power to make them so efficient and, again, steam power has a problem of following changing loads.

      Solar power is already qu

      • " If we are going to be honest about the cost of solar power then we need to add in the cost of the storage and/or backup. After that it's not so cheap."

        Yes but creating a battery is a one-off capital cost and a not continuous one like a fossil fuel.
        • Re: (Score:3, Insightful)

          by blindseer ( 891256 )

          Yes but creating a battery is a one-off capital cost and a not continuous one like a fossil fuel.

          Said the person that does not understand levelized cost of energy.

          The LCOE takes into account the cost of the fuel. When measured on LCOE rooftop solar costs more than natural gas peaking, and utility scale solar costs more than combined cycle natural gas.
          https://en.wikipedia.org/wiki/... [wikipedia.org]

          Both utility scale solar and combined cycle natural gas will need something like natural gas peaking power or batteries to match supply to demand. If there are batteries cheaper than natural gas peaking plants then you ar

          • by ras ( 84108 ) <russell+slashdot ... rt DOT id DOT au> on Tuesday April 14, 2020 @05:27AM (#59944574) Homepage

            Just in case anybody believes this rant:

            utility scale solar costs more than combined cycle natural gas.

            Actual figures from the link he quotes as his source: https://en.wikipedia.org/wiki/Cost_of_electricity_by_source#Lazard_(2019)_2 [wikipedia.org]:

            • Solar PV—Thin Film Utility Scale min:$32 max:$42
            • Gas Combined Cycle min:$44 max:$68

            As for:

            When measured on LCOE rooftop solar costs more than natural gas peaking

            True, but irrelevant. People who install rooftop don't pay LCOE. They pay retail - something like 3 times LCOE + wholesalers margin. Surprise, surprise, multiply any of nuclear / fossil by a factor of 3 and it's more expensive than rooftop. Maybe that's why people are installing rooftop?

            The figures for home batteries vs grid batteries are also effected by retail by wholesale price. Its true grid batteries for bulk storage don't make much sense. But combine that 3 fold price difference with Elon's (in fact almost everyone's) prediction of $100/kwHr 5k cycle batteries, and suddenly they are looking good - $.20 / kwHr good. $.20 doesn't wonderful - but it costs $0.30 to buy nuclear at retail.

      • In both cases the solution for now

        I stopped reading when you said "solution for now" in reply to the parents comment about the future. You clearly are having your own conversation in your head. You must be, because if you were having a conversation with someone else you'd have shilled for nuclear energy by now.

        • Re: (Score:2, Insightful)

          by blindseer ( 891256 )

          I stopped reading when you said "solution for now" in reply to the parents comment about the future.

          Then you missed the point that any technology can have more than one application, or solve more than one problem. Natural gas turbines are used to match load to supply regardless on if the supply varies, as is the case with wind and solar, or the demand, as is the case with steam power unable to match shifting demand over the day.

          A battery will in effect be a replacement for natural gas turbines. That is assuming they can bring the cost of these batteries below that cost. When or if that happens then the

      • These can be brought on line quickly but they burn twice the fuel for the same electricity as combined cycle turbines.
        Nope.
        You want to say: a combined cycle plant can reach up to 60% efficiency. And gas turbine alone only 42%

        What you ignore: every steam powered plant can only reach about 42%.

        steam power has a problem of following changing loads.
        That is simply wrong. Most load following plants are steam powered. You again mix things up because you don't know what load following means. Gas turbine are prima

      • by Socguy ( 933973 )
        Not quite. Solar has a lot of runway yet to continue to come down in cost. It won't be that many more years till solar is hands down the cheapest. In the interm, solar can afford to be slightly more expensive because it generates power that's more valuable due to the fact it's generated at a time of day where prices are the highest. Wind right now is the cheapest form of generation in most places hands down. Storage helps but you don't need as much storage as folks think. Wind and solar are complement
  • Fuel is storage (Score:2, Insightful)

    by blindseer ( 891256 )

    What is likely still the cheapest means to store electricity for on demand use is with a tank of natural gas. Natural gas that can be used to fuel a turbine connected to a generator.

    What might be cheaper than that in some locations is the use of a hydroelectric dam, the water behind the dam is an inherent energy storage device required for the operation of the dam. A dam that we already know how to raise and lower power output relatively quickly, and can be used to store energy with relatively little loss

    • by AmiMoJo ( 196126 )

      This sounds nice until people realize that it's really hard to keep the molten salt hot on solar power alone.

      No that just means they didn't build enough collectors. Even on a cloudy day it's not dark like night time, right? You just need more mirrors to harvest the available energy from a wider area.

      Wind and solar power takes a lot of land. Either will require something on the order of one square meter for every 10 watts.

      You think a 25kW wind turbine needs 2.5 square kilometres to itself?

      In reality turbines are generally placed about 5-6 rotor diameters apart, geography permitting, and all of the land that isn't part of the base can be used for other stuff.

      • No that just means they didn't build enough collectors. Even on a cloudy day it's not dark like night time, right? You just need more mirrors to harvest the available energy from a wider area.

        It's not just the area, it's the temperature. The sun only gets so hot, and if the temperature of the sun available is not hot enough through the day then losses at night could mean the salt solidifies. Or at least the plant produces no power.

        You think a 25kW wind turbine needs 2.5 square kilometres to itself?

        It appears it needs far more than that.
        https://www.withouthotair.com/... [withouthotair.com]

        In reality turbines are generally placed about 5-6 rotor diameters apart, geography permitting, and all of the land that isn't part of the base can be used for other stuff.

        I did specify the possibility of using the land area for both wind and solar power. Because wind power gets somewhere on the order of magnitude of 10 W/m^2, as does solar, even if you combine t

        • by AmiMoJo ( 196126 )

          It's not just the area, it's the temperature. The sun only gets so hot, and if the temperature of the sun available is not hot enough through the day then losses at night could mean the salt solidifies.

          Um... That's not how solar collectors work. They don't reflect heat from the sun, they reflect light.

          It appears it needs far more than that.

          No, your link says they need to be spaced 5 diameters apart, not that you need to dedicate a vast amount of land just to a wind turbine and nothing else.

          Anyway a 25kW turbine with a blame diameter or 14m (e.g. https://en.wind-turbine.com/wi... [wind-turbine.com]) would therefore need to be 70m from other turbines. Let's use squares to simplify packing, that means 140m2. Not 2,500m2 or "far more" as you claim.

          Your own link comp

          • 70 meters by 70 meters is an area of 4900 square meters. If there is a 25 kW windmill in this area then that's a bit more than 5 W/m^2. Then we have to take into account the capacity factor. There's other matters to consider as well. The point is that 5 W/m^2 is a good order of magnitude number. The link I gave says 2.2 watts but then that was making assumptions on the speed of the wind and such. Assuming a capacity factor of 0.3 and 2.2 W/m^2 is optimistic.

            Your comments on solar power makes no sense.

  • by blindseer ( 891256 ) <blindseer.earthlink@net> on Tuesday April 14, 2020 @02:38AM (#59944242)

    I keep hearing people talk about the possibility of a hydrogen based economy. This is obvious nonsense because hydrogen is not an energy source, it's merely a means to store and transport energy.

    Let's assume that this use of hydrogen as a means of energy storage and transport is what they mean by "hydrogen economy". Perhaps the obvious question is what it stopping them? It's not like we don't know how to produce it. We do know how to produce hydrogen but not do so cheaply. Perhaps this technology allows for hydrogen production cheap enough to use as a fuel.

    One problem holding hydrogen back as a fuel is a means to convert it into useful energy. A fuel cell is nice but this is not likely practical for making cement, making an airplane fly, or getting satellites into space. In these cases it's just easier to burn it for heat.

    This then comes to another problem, storing the hydrogen. Hydrogen is not very energy dense. Liquefying it is only really practical for rockets, where the physics dictate that liquid hydrogen really beats out many other fuels and the economic considerations are very unique. Even then there's plenty of cases where people prefer kerosene or methane fuel. In rockets and airplanes this kerosene might be highly refined but it's still kerosene. For things like cement kilns they don't much care about the purity of the fuel, or even what fuel they burn, so hydrogen might be useful but still the problems of hydrogen liking to embrittle many metals is problematic.

    As it turns out we know how to store hydrogen in liquid form that is easy to transport and store. In a form useful for aircraft, rockets, and even heating fuel. That is to attach hydrogen atoms to strings of carbon atoms. These strings might vary in length to optimize for different properties, and we know how to separate them out and mix them together for these properties.

    In short, the hydrogen economy will look a lot like the petroleum economy. The difference being that instead of drilling for hydrocarbons from the ground we will make them from onshore wind, hydro, geothermal, and nuclear power. The hydrogen from this process will likely be far more valuable as an industrial feedstock for chemical production than to use for producing electricity.

  • Classical electrolyzers work with a KOH electrolyte, which is a base, not an acid. They also don't require precious metals.
  • I think people are missing the point here as a Fuel cell has been created that stores electrical energy as Hydrogen
    and in a reversible reaction can convert this Hydrogen back into Electricity , this is all in one device.

    As long as you have have enough storage for the Hydrogen gas you could store alot of energy in this Fuel cell.
    • I think people are missing the point here as a Fuel cell has been created that stores electrical energy as Hydrogen
      and in a reversible reaction can convert this Hydrogen back into Electricity , this is all in one device.

      As long as you have have enough storage for the Hydrogen gas you could store alot of energy in this Fuel cell.

      I believe people are missing that this doesn't need to take power from renewable energy.

      I took a tour of a pumped hydro storage facility operated by the Tennessee Valley Authority. They use this facility for both daily and seasonal variation in demand. When there's the daily morning peak they open the gates and get more power out of the dam, and again for the evening peak. Over night they pump water back into the lake behind the dam. Where are they getting this energy? They tell us here: https://www.t [tva.gov]

      • I believe people are missing that this doesn't need to take power from renewable energy.

        I think the reason the subject says it stores "renewable" energy as hydrogen is because fossil fuel is already stored energy. It sits there as coal for a million years until you're ready to burn it.

        Reservoirs with pumped hydro are a great source of energy storage, but only if you have a reservoir handy.

        • I think the reason the subject says it stores "renewable" energy as hydrogen is because fossil fuel is already stored energy. It sits there as coal for a million years until you're ready to burn it.

          Perhaps that is one way to read that. Not sure that's where they were going with it. It turns out that fast acting storage, like the big batteries Tesla has been selling, is useful for coal power. That big battery in Australia was built as an aid for all the windmills that they have out there but when a large coal plant had a problem the batteries saved the grid from an outage.

          Reservoirs with pumped hydro are a great source of energy storage, but only if you have a reservoir handy.

          Sure, but it's not like it's a lack of storage that is holding back solar power. We had cheap storage on the grid for decades an

      • There is a series of 4 dams in AZ that does the same thing. Lets them handle larger runs without dumping their storage potential. Really cool. I think its the salt river or something.

    • by AHuxley ( 892839 )
      The good part is a nation will no longer need to import metal, oil from different nations.

      No more supporting faiths of war, war lords, juntas, monarchies, the export demands of 3rd and 4th world nations.

      Domestic hydrogen production. Japan will sell the hydrogen ready van, truck, SUV, car design.
      Freedom for a lot of nations who have to keep buying car battery packs, oil, fully import expensive new all battery car designs.
      Hydrogen production and quality hydrogen car engineering from Japan. Freedom.
    • I think people are missing the point here as a Fuel cell has been created that stores electrical energy as Hydrogen and in a reversible reaction can convert this Hydrogen back into Electricity , this is all in one device.

      No, we get it. They've developed an energy storage device, functionally equivalent to a rechargeable battery. It has the fun property that it stores it's energy as hydrogen gas so its storage capacity is easy to vary. Neat trick, I'm sure there are places where it's useful. You still need to get the energy from somewhere which might be fossil fuels, solar, wind, hydro, or nuclear, all the usual suspects.

      What many seem to be getting in the weeds about is which energy source you'd use if you had an economical

  • There's a great article at Vox by David Roberts that runs the numbers for how cheap grid-scale storage of gigawatt-hours would have to be to make the overall combination of wind/solar and storage an affordable base-load equivalent. Turns out to be $20/kWh of storage capacity, about a tenth the cost of Li-On batteries right now.

    https://www.vox.com/energy-and... [vox.com]

    It does note that simulating 95% capacity is vastly easier, over $100/kWh, which is coming for Li-On in another generation. (GM is claiming, I thi

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