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hello and welcome to technically speaking where scientists and Engineers come together to chat about a common interest share knowledge and satisfy some curiosity I'm Antonia today I'm joined by Jasmin and Sophie to talk about methods of hydrogen production and why it's become a popular topic of discussion to start off with a little introduction from yourself Jasmin how is hydren relevant to what you do in your work yeah so I do a lot of research into decarbonization specifically ways of
achieving Net Zero and for quite a few sectors hydrogen is going to be really important in terms of reducing greenhouse gas emissions I've had a look at hydrogen as well and trying to put together a few different companies Net Zero strategies and some there is no alternative for high temperature heat apart from hydrogen y pretty much well I want to say widespread hygen's not widespread yet yeah it's an issue like currently hygien production is still quite limited so scaling up to what is
needed for large scale use is going to be an issue but there are lots of different ways of producing hydrogen yeah Sophie is this is your first time on the podcast could you introduce yourself and how hyren is relevant to what you're doing so I work in the nuclear industry as a chemical modeler one way of producing hydrogen potential is using nuclear power plants yeah I've in my team done a little bit of modeling looking at that and um yeah really interested in the how nuclear can play
its uh role into this fuel type nuclear is another I want to say future technology some people are uncertain about to what scale it will be so it's interesting to pair something else that is kind of an uncertain thing obviously quite um a new area of research yeah I mean I guess we've had nuclear power for well longer than I've existed so it's not as totally new but um Ever Changing new technology is coming out at the moment so it's definitely exciting field
to be in at the moment why do you think hydrogen and nuclear are an interesting topic for people to research now so yeah it's a really exciting time um in the nuc industry has been a bit of Renaissance um how we can help use it to reach Net Zero so it's really an interplay between Renewables and nucas seems to be the way forward to achieve that yeah in terms of hydrogen as we've mentioned already there's a lot of parts of Industry that are hard to move away from fossil fuels that need a source
that's not just electricity based but also in terms of manufacturing chemicals as well so pairing the two together and reducing the amount of carbon emissions is it's interesting science but it's also really important for the future of the world I guess Jasmine where have you seen a need for hydrogen in ter of like current amounts of hydrogen it's mostly in chemical production as well as in other industrial processes like Iron and Steel making uh it's also been used a
little bit in transport so like in the early 2000s we had hydrogen fuel cell Vehicles which kind of became fell out of popularity CU electric cars became all the range all the range or all the range cuz I thought hydrogen had all the range sorry I had to get that pun in um yeah and in future uses of Hy it will be in industrial decarbonization so decarbonizing processes that need high heat demand we might see some in transport specifically for like heavy Goods Vehicles another application for
hydrogen would just be in just making like synthetic fuels because things like the aviation sector it's going to be really hard to decarbonize and we did have two guest speakers on the previous episode who talked about the um startup that was making a sustainable aviation fuel that uses hydrogen yeah that's the water e fuels episode yeah and another potential use of hydrogen in the future is actually in electricity so renewable energy sources so wind and solar
sometimes they produce excess or Surplus electricity so you need a way of storing it and I'll turn to batteries is to just convert that electricity into hydrogen and then we can use that hydrogen to generate electricity yeah I mean that's a really good point if you think about hydrogen and hydrogen bonds they're some of the strongest bonds that exist actually the use of hydrogen is is to store energy it's not as you would think of with fossil fuels where it's a fuel
where you you just dig out the ground and there you go you burn it so yeah that's the real way to think about of hydrogen as well is it's a way of transporting energy from one form to another and locking it in to use obviously energy is an increasing market demand for hydrogen but it's not at the moment so do we know what portion of hydrogen is used in the various different applications like chemicals versus metal definitely petrochemicals um so ammonia methanol would be the two
biggest uses for hydrogen right now they account for over 60% of the market right now for hydrogen that's actually lower than I thought I thought it was all going to be for ammonia and then therefore fertilized production what you call ammonia production petrochemical ammonia no but hydrogen produced from natural gases would be classed Under the Umbrella of petrochemicals that makes sense to me the one other use that we've not really mentioned is the use of liquefied hydrogen in space launches I
suppose because they make such a small amount of the demand for hydrogen but maybe in the future it will be more common if we mine on on the moon but before we get there let's talk about actually how are we producing hydrogen right now currently there's like four different ways of producing hydrogen the main one is from fossil fuel so depending on if you use coal or natural gas um that can be called black brown or gray hydrogen I think we we should explained so people have come up with this
rainbow of calling hydrogen kind of like people saying electricity from Renewables is green yeah electricity even though it does it physically is not a different color yeah neither is this hydrogen is not physically a different color it's just the way that people have decided the colors indicate a different synthesis route if you add on carbon capture storage to your fossil fuel hydrogen and that then becomes blue hydrogen the other ways of making hydrogen currently is using electrolysis
so again depending on the type of electricity that you use the color can change renewable electricity I window solar that can be called Green hydrogen although if you use solar it can also be called yellow hydrogen there's lots of different colors and there's actually no consistency in some of the labeling if you paraliz a hydrocarbon basically pyy biomass so pyy means if you heat it in the absence of oxygen it's called turquoise hydrogen the two ways of making hydrogen right now are in
refineries so that's usually your gray hydrogen or your blue hydrogen and the other way of making hydrogen it's a byproduct of the chloro Alkali industry when you're electrolyzing sodium chloride Solutions and you end up with hydrogen as a byproduct how do you get hydren from coal or fossil fuel in Coal you do something called gasification so you produce a sing gas that's a mixture of carbon monoxide hydrogen and I release some water VOR and some other gases in it and you then just separate
out the hydrogen from the same gas mixture for natural gas you do something called steam methane reforming where you basically break the bonds between the carbon and the hydrogen and I believe you also end up with some Co in that process as well and how do people separate these gases so effectively that you can get hydrogen and separate from another gas that Co sorry carbon monoxide you have something that's called a pressure swing absorption which will separate out the hydrogen from
other things that are being produced is it they have different preferential absorption rates to an absortion medium yeah cuz it depends on the affinity for the different molecule and what the absorbent material is and that's a similar process for caral capture storage isn't it yeah so you you've got like one set to get the hydrogen and then you have another set to get the carbon monoxide SL the CO2 if we didn't have that second step we would just be emitting the CO2 into our atmosphere
yeah basically so it's almost as if it's the same as if we burnt the fossil fuel right yeah so that's why unabated so without carbon capture and storage for coal or natural gas based hydrogen is pretty bad and that's why you want to add CCS onto it I guess that brings us on to why the green and pink SL yellow hydrogen the renewable and the nuclear electrolysis Roots may be better coming to what electrolysis is what we're looking at here is breaking apart a
water molecule to form your hydrogen gas and your oxygen gas through the use of electricity again the strength of um ho bond in in water is really strong it's like abnormally strong so it's quite a unique thing that water is liquid at the temperature and pressure that it is yeah definitely that is what makes life on on earth water and it's interesting properties and extreme hydrogen bond networks that occur so yeah it's a interesting molecule although it's very
small and looks quite innocent so yeah so that's that's what the electrolysis is doing and if you think about breaking apart a bond basically you're providing energy to to overcome the strength of that interaction now there's two ways you can kind of go about that you can either use purely electricity to power that electrolysis reaction or you can add a little bit of heat in there and that will weaken the bonds slightly which means you need less electricity to
break that molecu part typically when we do think about using some of the electrolysis methods in some of the other applications so when we're using renewable electricity or typically when we do do think about nuclear electricity as well it is just using just electricity and we're not thinking about any thermal properties but with nuclear especially as we move potentially to newer designs of reactors such as high temperature gas cooled reactors the idea is well we've already got really high
temperatures going on why don't we take advantage of this instead of it being an unnecessary byproduct that we then need to deal with later why not actually utilize it so yeah there's a lot of different potential designs of electrolysis Technologies out there that could really utilize this so at the moment that's really steady research on alkaline electrolysis where slightly weaken the with having potassium hydroxide or another alkaline solution but essentially it's electricity that
breaks that water apart but there's new technologies such as solid o oxidized electrolysis that means that we can start using some of those thermal properties because we use steam instead of water okay so I was going to ask what kind of temperatures are we talking when we say higher temperature water electrolysis that is a question to kind of solve of at what point to does this all come together within a reactor design but as long as we've got boiling water that that's what will help the
process go which is definitely very well achieved and how hot is a nuclear reactor or the high temperature nuclear reactors like just just for a scale like is it as hot as the sun with the high temperature gas cooled reactors which is the technology that we're looking at to couple with about 750 950° C so you can see that's definitely going to produce steam well that's interesting in traditional fossil fuel burning boilers you can get heat recovery of the flu
gases but if we are losing that then we kind of lost a source of heat in a way I guess the pro of thinking about moving to what is referred to as pink or yellow hydrogen with nuclear is that you can use the heat from that process and you can use the electricity directly from nuclear as well or potentially from other sources if you if you so should want to but the idea of coupling it is to use that electricity as well and it not produce CO2 like our fossil fuel
plants would is is this something we could couple with small modular reactors or is this like much more the large hinkly Point C scale reactors good question I think the idea is if we're going to be coupling hydrogen production it's probably going to be on the larger scale um it just makes sense of economy and the infrastructure needed to to do it as well it's probably much more sensible for our normal size hly Point C reactor sizes but I'm not ruling it out
I definitely can't say no to smrs small modular reactors ever playing that role yeah I just bring it up because one of the challenges is where hydrogen is going to come from if we need it everywhere and do we BR build hydrogen networks are we using hydrogen to transport hydrogen to then use elsewhere because hydren pipelines aren't a thing like our natural gas pipeline good question I I don't have an answer on the the future of smrs producing hydrogen but it is that interesting thing of the
economics of of hydrogen production of when do you use your reactor to make the hydrogen and when do you make use it just to make electricity and that is a big question to be answered when we're looking at the economics of using any process to make hydrant particularly uh for my background nucleus there's a lot of modeling that's been done on that in my team but widely in the the industry as well what implications do you think this has on the work that you're doing
Jasmine decarbonization industrial hubs could be something that could be more applicable or more usable for some industry especially if they're located close is to a nuclear facility because an issue with hydren is just how to transport it there is quite a bit of research that's gone into how to transport hydrogen there's different ways that you could do it pipeline is is an option and there is actually work to convert gas pipelines into hydrogen pipelines but you can also do other
things like you could liquefier and then transport it that way or you could store hydrogen in things called metal organic Frameworks or you can also convert hydrogen into what's known as a liquid organic hydrogen carrier which is a chemical uh that contains hydrogen which will release the hydrogen when you do make changes to the temperature or pressure so there's lots of different ways of moving hydrogen but right now hydrogen is is produced really close to where it's used just because
transporting gets really expensive right now but if we do see like a really big increase in demand obviously there's going to be greater needs for both hydrogen production as well as ways of transporting it and the challenge of transporting it is because it's the smallest molecule that exists so if you have leaks in like equipment that's transporting it that's a bit of an issue but also hydrogen is a bit of an weird molecule because it has different properties to other gases for most gases
the temperature increas es when you compress it but the hydrogen it's the opposite it actually gets colder what yeah no I don't know why I didn't know that so pry Weir thing but also the main thing about why hydrogen is going to be really tricky to transport is that it's a really dangerous gas flammability cuz it has a much higher flammability range than natural gas so even at very low concentrations it will combust but even at very high concentrations it can
combust I can't remember the exact range but it's much higher than methane and other flammable gases and we found a way of making natural gas smelly so we can actually detect it a bit easier with the naked nose but the thing is you need to find a chemical that doesn't react with hydrogen because hydrogen is very uh reactive which is actually another issue for pipelines because they call it embrittlement don't they yeah because hydr is really reactive so you need to
use a material that is not going to degrade from having to like carry hydrogen just a whole host of complications to find the answer to yeah um that might be a future episode so I suppose if we were to use nuclear do we call it thermochemical production using the heat as well as electricity to break PL water into hydrog how far along are we with doing that because I've not heard of this technology before in terms of how ready this technology is to go on the market it it's it's not it's not
there yet it's not something you could buy off the shelf and and know it will 100% work tried tested with a nuclear power plant so um there's a lot of research that needs to be done there to kind of improve that as well um and yeah so I think probably if anyone's familiar with these technology Readiness gradings um trls it's probably about a six so it you can kind of see it's not at the point where you're ready to deploy oh so TRL 6 it's almost somewhere where people would invest in
it because it's kind of proven enough technically it works but the actual economics and making it physically happen is what needs developing yeah no well I I definitely agree I I guess I just wanted to make the point it's not something that you can buy off the shelf but it's still some research but we're at a point yeah where some exciting stuff could be happening TRL or technical Rance level six that's basically means you have a prototype system that works yeah so TRL 7 would be
an actual demonstration pilot plant and then basically anything after that basically you're going industrial scale yeah so it's not quite ready yet but how do you think this will change energy use or chemical production if we did have wider scale hydrogen production yeah if we have more hydrogen then there's going to be more ways that we can use it in the future So currently for the UK at least it's predicted that most of the hydrogen is going to be used in industry
as well as maybe a little bit in transport and electricity but we could see it for other things we could see more chemicals being made using hydrogen if we can get lots of green hydrogen or hydrogen from thermochemical splitting cuz right now a lot of chemicals are based on fossil fuels so we need a way of making chemicals that don't involve fossil fuels and this kind of links to our biobased Plastics episode but we couldn't make plastic from hydrogen directly could we no have to convert it
you need a source of carbon but it's possible yeah it's possible that's good yeah and I think we Ted on energy storage before because hydren is kind of an energy storage Medium as opposed to a direct energy source yeah so I think one of the biggest challenges with the way our electricity generation is going is we have a lot of Renewables which are intermittent in its production if we have more nuclear we have that base load energy but anything to actually respond to
Peaks uh what we what we call um like demand response we we wouldn't have unless we had something like hydrogen and other storage methods right yeah yeah exactly here's the question if we talk about using hydrogen for high temperature stuff or fossil fuels for high temperature stuff do you think carbon capture store storage is going to develop faster than any of the Greener ways of producing hydrogen that's a good question not sure like there's already carbon capture and storage being used on
Industrial scales and right now capacity is definitely a lot higher than what capacity is for electrolysis and green hydrogen production but I think in the future there's going to be a lot more green hydrogen but I think there will still be a place for CCS but maybe not for fossil fuels probably for Bio energy just because in the run up to 2050 and you want to be at zero you really do need to have phased out a huge chunk of your fossil fuel usage so that means no
more gas coal and oil yeah I guess just to add to that that if you arguing that if we can get carbon capture let's just carry on using fossil fuels is there's a lot more than just the CO2 emissions when you think about fossil fuels it's the fact do we want to keep digging these things out the ground and work more and more harder to do so yeah even if carbon capture does get to that great point I I think that we shouldn't be saying no to producing hydrogen in a
more green or pink way yeah I think this is something we've not Ted on which is actually where's the water for electris is going to come from yeah that's a really big concern that's something that needs a lot more research into because you can use desalinization for sea water cuz hypothetically there's lots of sea water but then you have issues around that because like you need to you need industrial scale in desalinization specific especially in places that have
lots of renewable capacity but very little fresh water supplies I the Middle East you could use like you could use other water sources but then You' be competing with other water uses so like domestic water uses industrial water uses so you could end up with competitions for Water Resources so it's something that really does need a lot more looking into definitely cuz I mean it comes to the economics of it as well if you are doing desalinization then you're going to have
to have the input energy to do that in the first place does it out away the energy that you produce yeah exactly and store in hydrogen so yeah and I've heard that the purity of water also matters so we couldn't just directly use Sea waterer for electrolysis we have to remove the salt yeah so we're basically competing for potable or drinking water potentially yeah which is also a concern that people have for the future yeah I mean it's also a it was also an issue
with biofuels cuz it's like food versus energy so now it's like water versus energy and I think that's it when we first you know first idea about hydrogen is yeah it's um a very strong bond so we're just using it to Star Energy but the pro is water's everywhere like you said it's the question is well is the right water everywhere so and then also yeah we produce a nice gas at the end that's could be cyclic and it's not going to produce any horrible of a side products but yeah how do we how do we
transport it so there's still some big questions on all that I think this was that was the perfect wrap up for this episode so unintentional but glad I did it and we might touch on this topic again in the future thanks for listening the views expressed in this podcast belong entirely to the person that said them did not represent any industry or organization if you enjoyed listening to these views it would really help us out if you could rate US leave a review and
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