Podcast episode

Seaweed: the next big thing in sustainable agriculture? w/ Scott Spillias, Uni of Queensland – EP188

Seaweed is being advanced as a potentially important future food source, the greater farming and consumption of which could avoid environmental impacts associated with other agricultural production, especially of beef. Scott Spillias has recently submitted a PhD thesis at the University of Queensland on seaweed farming, and he’s been getting a lot of attention regarding his findings on seaweed’s potential. Show host Gene Tunny and Tim Hughes talk with Scott about the potential of using seaweed as an alternative food source. 

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What’s covered in EP188

  • The importance of plant-based foods in our diets. (1:36)
  • The market for plant-based foods is growing. (9:39)
  • Estimating the environmental impact of food production – the Economist’s banana index. (14:03)
  • Scott’ Spillias’s research on seaweed farming. (27:27)
  • How do you farm seaweed? What does it involve? (30:04)
  • Where can we grow seaweed in Australia? (35:14)
  • Seaweed has the potential to remove 2.6 billion tonnes of CO2 from the atmosphere per year. (40:02)
  • What kind of seaweed is growing in the world? (44:49)
  • How does seaweed farming prevent biodiversity loss and climate change? (49:50)

Links relevant to the conversation

Scott Spillias’s UQ page:

Australian ABC News article on Scott’s research “Seaweed researchers find bright future for underwater crop”:

Guardian Australia article on Scott’s research “Food, feed and fuel: global seaweed industry could reduce land needed for farming by 110m hectares, study finds”:

Economist article featuring the banana index:

A different way to measure the climate impact of food | The Economist

UN and World Bank reports on food and climate:

Chapter 5 : Food Security — Special Report on Climate Change and Land

What You Need to Know About Food Security and Climate Change

Review of scientific evidence on “Risks and benefits of consuming edible seaweeds”:

Please note the key message of the above review:

“If the potential functional food and nutraceutical applications of seaweeds are to be realized, more evidence from human intervention studies is needed to evaluate the nutritional benefits of seaweeds and the efficacy of their purported bioactive components.”

Seaweed: the next big thing in sustainable agriculture? w/ Scott Spillias, Uni of Queensland – EP188

N.B. This is a lightly edited version of a transcript originally created using the AI application It may not be 100 percent accurate, but should be pretty close. If you’d like to quote from it, please check the quoted segment in the recording.

Gene Tunny  00:06

Welcome to the Economics Explored podcast, a frank and fearless exploration of important economic issues. I’m your host Gene Tunny. I’m a professional economist and former Australian Treasury official. The aim of this show is to help you better understand the big economic issues affecting all our lives. We do this by considering the theory evidence and by hearing a wide range of views. I’m delighted that you can join me for this episode, please check out the show notes for relevant information. Now on to the show. Thanks for tuning into the show. In this episode, I’m talking about a bit of a quirky topic with Tim Hughes. My colleague at Adapt E1conomics, Tim helps me out with business development. We’re talking about seaweed. So a little bit quirky. Yeah, but there’s a reason for it. And I might just have a brief chat with Tim about that. Tim, good to be chatting with you. Yeah. Good to be here, Gene. So Tim, we had a conversation with Scott Sebelius at University of Queensland, he’s been doing a PhD on seaweed. And there is a logic to looking at seaweed because there’s this conversation going on about what future food sources are. That’s where a couple of different reasons. So you thought this would be a good topic, didn’t you to cover?

Tim Hughes  01:36

Yeah, I think it’s really relevant because there’s clearly a huge increase in the demand for meat, certainly in places like China, where the the amount of meat per capita has has gone up remarkably, over the last 20 years. And but around the world in general, and this has been well documented the pitfalls and the dangers for the environment, in that mass production of meat. So there’s a lot of plant based foods or, you know, meat alternatives, for instance, that are coming through, which, you know, there’s a lot of good research to show that that can help the situation. Remarkably, and also be good for us. Like, you know, I don’t think there’s any nutritional advice out there that says to eat less fruit and veg, maybe a bit less fruit but on the whole It’s like eating plants is good for us.

Gene Tunny  02:28

Well, according to Kelly Starrett, oh, we’ve got to eat 800 grams of fruit and vegetables each day, isn’t that right? That’s right. Yeah. optimal health. Now that’s, that’s a challenge.

Tim Hughes  02:38

It’s a really good is excellent book built to move has just been out recently. And I think he borrowed that from someone else. I can’t remember who originally came up with that. But it’s, it’s worth sharing. Because yeah, it’s a very simple premise of having 800 grams a day of plant food. And so the premise being is like, because it’s very easy to just go for the stuff you like, if you’re like kiwi fruit, for instance, if you have 800 grams of kiwi fruit, well, you’re gonna get sick of it. So the idea with just 800 grams and not putting any stipulation on what it is, is that people will generally mix it up a little bit, just to get that variety. But if you want a direction with it, the direction would be to get a good array of colours, primarily vegetables, and some fruit and 800 grams a day is a good target

Gene Tunny  03:30

Right, okay. So I thought this would be okay, this is a bit of a quirky topic, but I think it is relevant. And it’s, it’s something that we should look at on this show or consider on this show. Because, well, food security is incredibly important. And this is another way we could help improve food security, I mean seaweeds and other possible source of macronutrients as they call it. So it’s got some protein in it has an ad. And then there’s some mean carbohydrates, I suppose.

Tim Hughes  04:01

Yeah, I’m not too sure if the nutritional constitution of the different seaweeds but I know, they always score highly on the nutritional scores as in, they’re not high in fat, they have no fairly high vitamin content. But it’s what you can do with it. And this is where one of the questions that comes into I guess that there’s only so much seaweed, I guess that in its raw state or cooked state that people would eat, but it’s the opportunity of using it and processing it to create other foods. That is where a lot of the opportunities are. But it’s also where a lot of the questions are as to well depending on those processes. And you know how healthy the final product would be, because any process generally degrades the food quality or the nutritional quality at some point. Our friend Paul Taylor, who we listen to quite a bit he’s he’s got a really cool way of looking at food which is low a chai, which is low human interference and So if it’s an ingredient and not full of ingredients, and it’s generally good to eat. And so when we look at something like seaweed or kelp or whatever, it’s great. But then we do have to really consider the processes that then it might have to go through before it ends up on the plate as whatever it is. Because there’s, yeah, it’s probably reasonable to expect we’re only going to eat so much kelp or seaweed.

Gene Tunny  05:21

Well, well, yeah. So this is what I want to talk about. And think about, because this has been pushed by certain bodies and such as well, UN and other international organisations. They’re arguing we need to, to eat more plant based food, more plants, essentially. And seaweed is one of those potential foods. And so I thought, well, this is interesting. But and, and the reason that these bodies and I’m not saying whether this is good or bad at this stage, the reason that these international organisations are doing that is because they’re concerned about the contribution of, of agriculture currently for the food that it produces the contribution of that to climate change. They’re concerned that well, this is a major source of greenhouse gas emissions, I think it accounts for on one estimate. Well, looks like it’s a bit, there’s a wide range. In the IPCC report on chapter five on food security, about 21 to 37%, of total greenhouse gas emissions are attributable to the food system. That’s a fairly wide range, I guess that shows how much uncertainty there is about all of this stuff, right. I mean, you know, it could be a fifth or it could be over a third, we, we just don’t know, but I guess it’s hard, because you’ve got to think about the impacts on the land and what it means for vegetation, and also transporting the food to all of the, the emissions involved in that. So

Tim Hughes  06:52

Yeah, and the other thing is like, I mean, I think it’s great, personally, because I think any exploration of securing different plant based foods for human or animal consumption is a good thing. And it needs to be, you know, researched thoroughly and taken seriously. But it is interesting that, you know, this could be done on a scale, because it now this is going to have to take a certain amount of space in the ocean. And so that’s going to be obviously a consideration as to where and how, but it’s certainly not beyond the realms of you know, it’s certainly not a barrier, we have a lot of ocean to use.

Gene Tunny  07:32

And this is what Scott’s research is on. So we’ll talk about, we talked, we talked about that with Scott. Yeah. So that was, that was really interesting. So I might just read from this UN report. But what the UN writes are theirs on their website, I’ll put a link in the show notes, alternative proteins, such as plant based meat and dairy substitutes, insect based proteins and cell based cultivated meat, provide promising prospects and are attracting growing demand financial investment and technological innovation. So there’s all of this research going on and r&d into these alternative food sources. Now, we don’t want a situation of course, where the UN or even our own governments tell us you must eat. It’s so you must eat cricket. So you must eat seaweed. We don’t want that at all, where we that we believe in, in freedom and liberty on the show for sure. So we don’t want that. My take on this would be to the extent there is a concern with the existing food system and contributions to greenhouse gases, and we need to do something about that, then the way to do it is get the policy settings, right. If we can get an international agreement on a carbon price, for example, that’s one way that you could do it. If you’re worried about land clearing for agriculture, then you could you could have things like biodiversity offsets, or that sort of thing whereby they have to try and improve the condition of the land somewhere else, or, or try and protect species somewhere else. Yeah, there are these sort of mitigating or offsetting actions that could be taken that we could require farmers to undertake so I think, so I wouldn’t want to have anybody telling us you’ve got to eat this, this seaweed or you have to eat crickets. But it’s about getting the policy settings right and and assuming that there will be action on greenhouse gases and we will be decarbonizing and we there will be changes over the next few decades, then look, it’s fair enough that there are people like Scott researching seaweed.

Tim Hughes  09:39

Yeah. And I think that the market is really strong in determining these outcomes. Like a lot of people want to eat clean, they want to eat healthily. And there is concern about you know, the amount of meat being eaten so, and it’s not to say that meat shouldn’t be eaten. That’s a choice for the individual. But the amount of meat that has been eaten And it’s certainly of question to the environment and also to your own health. I mean, there’s only, you know, there’s only so much meat that we should eat, I guess. And it shouldn’t be a choice. But I think a lot of people are really interested and willing to try these new plant based foods, you know, plant based meats, but especially if the company can show that they’re doing the best they can towards sustainability, ethical farming methods, etc. People care about that. And I think that market will drive the popularity of a lot of this research and a lot of the companies who might come into the market, because there’s a hunger if you like for, for these solutions, you know, a lot of people want to want to see these foods on the shelves.

Gene Tunny  10:47

We are seeing them on the shelves. Now, Coles and Woollies aren’t really the plant based. Yeah, and it’s good, you know, based meat. And

Tim Hughes  10:55

it’s not cheap, you know, which is one of those things that I guess with scale, the price can come down from that, because it’s hard to pay more for a lot of these, these foods, but if they can be really shown to be highly nutritious, and tick all those boxes of sustainability, etc. I think there’s the market will drive the success of those companies.

Gene Tunny  11:19

Yeah. And on seaweed, there was a study I found, while I was preparing for this, that I think there’s some evidence that seaweed can help reduce some health conditions like if you eat enough of it, and apparently it’s in one in five Japanese meals. So sushi, for example, it’s in sushi, isn’t it? So I won’t have the wrap. Yeah. But apparently, it’s in one in five Japanese meal. So they eat much more of it than we do. And I think that’s what Scott’s looking at. Well, what if Western countries started eating? Or seaweed was making the same contribution as it does in say, Japan? Or perhaps China? Or Yeah.

Tim Hughes  11:57

And to be fair, like him, I’m coming from a very, you know, from a Western background, I guess, like, we don’t eat seaweed in our house as a general thing. And undoubtedly, there are loads of ways to eat natural seafood and a really great way that happens in different countries around the world. That’s part of their staple diet. And so in many ways, it’s just being open to try new things. And yeah, and generally, the closer it is to its natural state, you know, the state that it was when it was harvested, it’s going to be better for you. So there are certainly options there that can be, you know, good healthy options for us to use straightaway.

Gene Tunny  12:32

Yes. Look, I mean, this isn’t a health podcast. So I can’t comment on that. I mean, I think that’s probably true. I mean, the more process something is, the more likely it is to be bad for you. And, and this is why that study, if I remember correctly, I’ll put a link in the show notes is saying that, where you have a diet that has a lot more seaweed in it, the people are less likely to have conditions like diabetes, for instance,

Tim Hughes  13:00

I mean, I am coming from my background in the health industry. With this, I do bring some, some background into it. And it’s, you know, it is that thing of like, yeah, if you can eat these foods, or going back to Paul Taylor, you know, low human interference, then it’s generally going to be good for you if you have something like seaweed before it gets processed.

Gene Tunny  13:22

So Paul Taylor’s got the Mind, Body, Mind Body, Brain Project, Mind Body Brain Project podcast, which is really good. We both enjoy listening to it. Yeah, he’s great. Not actually friends with Paul to

Tim Hughes  13:37

say that, because we talk about him often, as we do with several other podcasts that we listen to. So yes, friends, and

Gene Tunny  13:45

we would love to have him on the show. So if you’re listening for and you want to come on the show, and you know, we’d love to have you on to chat.

Tim Hughes  13:51

But it’s back to the good science. That’s so yeah, sure. It’s not advice, but check out. Paul Taylor, and Andrew Huberman is also really good with nutritional based information. Yeah.

Gene Tunny  14:03

Yeah. So I just wanted to in this intro, I just wanted to give some reasoning for why we’re talking about seaweed just seems like a bit of a quirky thing to have on an economics podcast, but there is a some logic to it. And it’s all part of this thinking about what’s the impact on the environment of the food we eat. And the economist, the international newspaper comes out of London, that that had a recent article that I found really interesting, a different way to measure the climate impact of food. I’ll put a link in the show notes, but it’s probably paywalled. And what they did, did I tell you about this they they estimated the impact of food in terms of bananas, so they compared food, different types of food with bananas. Indexing greenhouse gas emissions to a single food gives a sense of how different foodstuffs rank. Unfortunately for carnivores, beef is bad for the environment, no matter how you slice it. Producing one kilogramme of Minsk causes as many emissions as 100 kilogrammes of bananas, call it a banana score of 109. Adjust for nutritional value and Beast, banana score, it’s a hard one to say, boost banana score falls to 50 for one calorie of beef mince causes 54 times as much carbon emissions as one calorie of banana by protein at scores seven. Okay, so it’s that’s a really cool way of looking at I like that. Well, there’s some great charts in the in that article. So it’s worth it’s worth looking at the economist is renowned for coming up with these quirky ways of looking at the issues. So they had the Big Mac Index, I think, I don’t know if they still do it, I’ll have to check. I haven’t read a physical edition of The Economist in years, I get to digitally and just look at the the articles that that are of interest. But they had this thing called the Big Mac Index, which compared the cost of living in different countries based on what a big man Oh, okay. Yeah. Okay, now trying to use that as an indicator of whether exchange rates are overvalued or undervalued. I think that’s what they’re doing, if I remember correctly. Yeah, so they’re good at quirky things like that.

Tim Hughes  16:13

I mean, as for this subject, being relevant to economics, I think it’s really, it’s really relevant, because, you know, the direction that’s going in it is to try and do these new plants on scale, which can absolutely make a difference, you know, to people’s health and to the back pocket,

Gene Tunny  16:32

potentially. So that’s why it’s one of the things I wanted to, that’s one of the things I think we need more information on is just what will this cost? And in terms of calories, I mean, meat is, although it’s it’s, it can be expensive, but it can be a good way of getting your well the protein, it’s a good way of getting protein in whereas how much seaweed would you have to eat to get an equivalent amount of protein? And that’s where I think the problem is that what’s the cost of that? Will we actually want to do it? Well, will our tastes adapt? I think that’s one of the problems with these. Thinking that we could move to an insect based diet or, or a plant or a plant based diet more broadly, I think there are going to be barriers to doing that.

Tim Hughes  17:23

I think it’s only ever going to make up a part of the daily intake, you know, as any food would. Yeah. But certainly protein is one of the hardest ones to fit in like going back to Kelly’s Tara and his book. He talks about 1.6 to two grammes of protein per kilo of body weight. I think I’m sorry, that was Paul Taylor. And but it’s actually it’s comparable with what Kelly Starr is has in his book. Yeah, it’s funny because he is all about grammes of protein, two pounds of body weight, so it sort of flips over the measurements, but it’s quite a lot, you know, I come to get that amount of protein in from food is is tricky. So that’s where supplements can come in. And sometimes that, you know, that’s where the protein supplements are really useful to be able to boost your protein intake. Because it can be Yeah, it’s harder to do with purely food. Do you mean protein powder? Yeah, protein powder was a supplement is a good way to to boost that, okay. And that’s largely from milk, but you can get it from plants and also pea protein. And you know, there’s, there’s proteins from all over the place. Yeah, that will suit pretty much everyone, you get vegan proteins that have been processed in a way that’s vegan friendly. So it is it can be done. But clearly, there’s a process with it.

Gene Tunny  18:42

One other thing I should mention, and my colleague, Steven Thornton has mentioned this to me in the past, and I can’t remember if I’ve spoken with Steven on this show about about it or not. I have to look through the archives. This is pushed to have lab grown meat. Have you heard about this? Yes, the hub, which I think would be great, because one of the problems with the plant based meat is that it doesn’t have the texture or you just know it’s not meat. Whereas this new the lab grown meat, it’s it’s actually me, but you don’t have to raise you don’t need the actual cattle for the you grow it in a lab. And that’s more arguably more humane or, you know, it’s it’s more ethical to do that.

Tim Hughes  19:29

Yeah, there were a couple of I’m going from memory here and the, from when I looked at it, and that was released a year or two ago. I remember reading about there were two main sources, there was a protein that had been isolated, which could be synthesised to be like meat. And so that was like, fairly straightforward. They were growing that in the lab but the other one involved taking cells from a cow foetus for instance, and then growing it from that. So different ethical sort of origins. And also, you know, I think people might be a little bit uncertain about, you know, people still have ethical considerations when they want to have these foods. And so yeah, there was, it was early days in the lab grown meat, and I’m not too sure where it’s progressed to now. But that’s where the plant based meats come in pretty well, because ethically, there’s nothing really that some too funky that’s happened in the origins, because we all care at the end of the day. I mean, I’m sure most of us care about, you know, for instance, if we are going to eat meat that we would like that animal to have had as good a life as possible before it’s been, yeah, mercilessly slaughtered. You know, but because I mean, there are instances, for instance of beef production where the animals never see the light of day. Peter Singer was talking about that recently. Yeah, he mentioned that. And so ethically, yeah, it’s not great. And

Gene Tunny  20:52

doing poultry production.

Tim Hughes  20:54

There’s poultry, I think it was mentioned about cows as well, based on such scale, where it’s just this, they don’t have any outdoor time or space, I’d have to

Gene Tunny  21:04

look into that. I mean, that was not like we do it in Australia. I mean, we have this was overseas, they spend a few months or however long it is in a feedlot. And then before they go

Tim Hughes  21:13

to the abattoir, but in an ABC article,

Gene Tunny  21:16

I’m not sure whether be efficient. I mean, that it anyway, I mean, I’ll have to look into that. I wasn’t aware of that. I know that I think that’s an issue with the chickens, some chickens that

Tim Hughes  21:27

kind of that kind of those farming practices. No. So it is that thing, ethics has a big part behind the meat. Anyway, for sure.

Gene Tunny  21:36

Just on the chickens, the chalks, that’s a really, they’re really, they’re a lot better for the environment than than beef. So if we can switch to eating a lot more chicken, and I like chicken. So I think that’s, that’s fine, that would improve things that would be good for the environment. And so maybe that’s what we do, we see a lot more poultry. But I think the way to do it, I mean, because people aren’t going to follow any directive from the UN, the UN says, oh, you should eat more seaweed or whatever. Not that they’re explicitly saying that, but they’re hinting at that sort of direction, that we should have more plant based food, rather than the government saying you should do this. If we get those policy settings, right, then people will be incentivized, or they will naturally move to food that is better for the environment, if we are properly pricing, the impact on the planet, the co2 emissions, then, as I’ve talked about, on this show, before, we’re going to make sure everyone else is doing it. Because there’s no point Australia wearing a hair shirt, or Australia, or another major agricultural producer, there’s no point us undertaking these measures if if other countries aren’t doing the same thing. So that’d be the one caveat I have on that.

Tim Hughes  22:55

And I think with that, because it’s a similar scenario to coal, for instance, isn’t it? And I think when technology takes you beyond the point, so for instance, when in the instance of coal, when it’s cheaper to produce renewable energy than it is to dig coal out of the ground, then that’s when people will follow suit. And I guess the same would happen with food, you know, food can be produced economically on a scale, that’s healthy, that’s of no great harm to the planet, people will go towards that when it becomes affordable and available enough.

Gene Tunny  23:28

Yeah, yeah, exactly. And maybe that’s what we need to see, to see happen. Yeah, I mean, it may be that there’s this flywheel effect are there are these economies of scale that they discover as they start doing this in, in life on a larger scale with seaweed, I mean, it looks like Scott and people like that are looking into opportunities to where seaweed could be grown. And then there could be a demand for it to industry starts expanding seaweed production, and then their costs go down. And that reduces the price of seaweed over time. And that could help that leads to additional demand.

Tim Hughes  24:06

So I guess, with government, if they were to champion or back those kinds of projects, and that’s where maybe, you know, their biggest input could be, you know, in making those circumstances in those conditions as available and smooth as possible. And that could also attract, you know, new investment into regions. So there’s no reason why not, you know, so governments can be influential in that regard.

Gene Tunny  24:30

Yeah, well, apparently Australia’s got quite a lot of favourable locations for seaweed growing, which is one of the things we learned from Scots. It’s

Tim Hughes  24:37

got a big coastline. Got a lot of a lot of coast.

Gene Tunny  24:41

Exactly. Okay. So not such a quirky issue, after all, but again, I just want to reinforce we’re not saying you must eat seaweed. We’d never say that. We’re saying that this is it’s one of these alternative food sources that is becoming well there’s a lot more interest in it now because have concerns over environmental impacts of our existing food production system? And also concerns about health. And there are people well, particularly rich role of the Rich Roll podcast. He’s a big believer in the plant based diet. Yeah, I’d find it challenging. But I wonder about the nutritional benefits of it, I can’t see how you can have a balanced diet without me. But then again, I’m not a nutritionist, and this is not a health show. And so that could be a discussion. Well, that’s a discussion for one of those shows, or we’re gonna have that discussion. Outside of the podcast in.

Tim Hughes  25:39

I think it’s relevant. It’s okay, like people shouldn’t be changing their habits on what we say. But I think it’s part of the discussion. And as part of that discussion, it’s, yeah, 100% people can generally do much better by eating more plants, you know, like, ritual is a good example of that,

Gene Tunny  25:57

relative to where we are at the moment that if we’re consuming too much, too many too much meat or too much junk in our diet, then certainly swapping that with plant based food or plants or seaweed, for example, or that probably is a good news. Well,

Tim Hughes  26:15

that’s just one of the premises behind the 800 grammes of plants a day is that if you eat that much, then you’re less likely to eat, or have the appetite to have other highly processed junk food around that. So naturally cuts down the amount of processed food that you would have. So it’s fairly, you know, it makes good sense

Gene Tunny  26:35

to him. Very good. Well, we should get on to the conversation with Scott. Let’s do it. We’ll play that. And, Tim, thanks for the conversation again. Thanks, Jim. Okay, we’ll take a short break here for a word from our sponsor.

Female speaker  26:51

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Gene Tunny  27:20

Now back to the show. God smelliest Welcome to the programme.

Scott Spillias  27:27

It’s nice to be here. Thanks for having me. Of course. Yes.

Gene Tunny  27:29

It’s good to have you on. Tim, came across an article mentioning your work your research work on seaweed recently and thought it would be great to have you on the show for a chat. So Tim, what was it about that article that that interested you? And made you want to chat with Scott?

Tim Hughes  27:49

Yeah, it was really interesting. You know, we’ve talked before about new sources of food for humans or animals or, you know, as a fuel source and seaweed that I’d heard of before, but not spoken about in the scale that you had been researching Scott with your team? So yeah, maybe you’d like to tell us a little bit about what you’ve been doing? Sure,

Scott Spillias  28:12

yeah. Well, I’m doing a whole bunch of work on seaweed farming and trying to understand kind of what the, I guess Sustainable Development implications of farming seaweed on a large scale would be for the planet, you know, how we can use seaweed to address some of the global challenges that we hear, talk about things like climate change, and food security and energy security, things like that. So PhD that I’m just completing now is covers a wide range of topics. But yeah, the article that was published recently, what we wanted to know is we wanted to kind of see what it would look like from a global perspective, if we were to farm seaweed, almost on a similar scale that we use the land to produce things like food, feed and fuel. And so what we basically did was we came up with a few different scenarios of seaweed use, aiming at looking at those kinds of those things food, feed and fuel. And we use a big economic model called glow biome, which is the global biosphere management model, which is located at a Yassa, which is a research institution and in Vienna. And we basically, what that globe globe icon does is it looks into the future looking at population growth and consumption in different regions. And it basically predicts where you would need to grow certain amounts of food or feedstock to match to meet that consumption into the future. And so we made the scenarios we looked at where seaweed could possibly be produced in the ocean, how much can be produced, and then said, Okay, well, what if we were to, instead of relying completely on the land to provide for the growing global consumption, what if we instead use seaweed for some of that supply? And then we looked at how that would affect potentially potentially land use, climate impacts things like that.

Gene Tunny  30:04

Right? That’s fascinating is go Casca. I’d love to ask a couple of questions. One, how do you farm? Seaweed? What does that involve? Because you’ve got seaweed growing in the, in the ocean, but how do you, you’re doing it in a specific area? And do you have a handoff? What’s it involve? And second, what does the research say about where we could grow it here in Australia?

Scott Spillias  30:29

Yeah, certainly see where you can grow seaweed and a whole bunch of different ways. And to be honest, that actually kind of depends on what kind of see where you’re growing. See where it is? A pretty general term, almost as general is just saying, Wait, can we grow plants? So how do we grow plants, you know, there’s 1000s, of different species of seaweeds, and they all have their kind of unique characteristics, both in terms of what we can use them for, but also in terms of what you would need to do in order to cultivate them. And in some, in some cases, seaweed can actually be quite complicated to cultivate, they have pretty complex life histories. But in some ways, they can also be a bit simpler than like terrestrial crops. For instance, you know, on land, if you want to farm corn, you often have to put in a lot of things like fertilisers and pesticides, water, seaweed, if you’re growing in the ocean, you don’t, you shouldn’t have to input any of those things. So basically, all you need to do is put the soil things out there on the line, and hopefully just grow in places where there’s enough nutrients, you don’t need that water, anything like that. So, of course, the kind of complicated thing. And like I mentioned, there’s two main ways. Seaweed is often grown these days, oftentimes, people so in places like Indonesia, or in Africa, people grow seaweed tend to tend to grow seaweeds, and kind of intertidal areas where you can walk out, stick some sticks in the sand or the mud in the bottom of the ocean, but some strings, some lines between them and grow the seaweed on that. That can have some implications for whatever habitat was there before. But there’s a lot of research these days going into floating farms. And this is something that’s already practised in places like China and Japan and Korea, where you actually have kind of floating lines or rafts that are attached to the bottom, and you’re growing seaweed on lines at the surface like that. And that, you know, you can imagine takes a bit more infrastructure. And certainly, if you want to have a platform that’s going to last for a while it can, it can require quite a bit of investment in materials from that perspective. So yeah, so your second question. Yeah, go ahead.

Tim Hughes  32:38

Because that I’m just intrigued by the, it seems like there’s a few different size or scales, that this can be done, obviously. So I think I saw in your article or the article that I noticed your work, the sort of smaller farmers doing what you were saying, like with the estuaries, you know, putting lines out in a in a small way for their own sort of little income, which is great. But I’m intrigued by what the bigger operations would look like. And if that means then that, you know, it’s the shipping free area that you know, I imagined, any shipping going through that would would cause a lot of damage. Is that the case? Like is that is that one of the big challenges is selling off those areas?

Scott Spillias  33:18

Yeah, I’m not 100%. Sure. I think though, there are definitely a governance issue. And that’s something where that was, that’s something that we had, we could definitely learn a lot. So here in Australia, where seaweed farming is almost non existent at the moment, growing but not like, very small. We can definitely learn a lot from places like China and Korea and Japan where they have been doing this for a long time. Yes, you’d probably want to separate those areas in the ocean from things like marine traffic. It’s, it’s kind of an interesting question, to what extent we can integrate seaweed farming with other marine uses, though, and certainly in places like Europe, there’s a lot of work going into understanding how we can integrate seaweed farms with things like offshore renewable energy, recognising the fact that, you know, if we’re gonna be putting more things like wind turbines in the ocean, which is a certainly a growing industry, then if you already have that infrastructure there, why don’t we just string some lines between the wind turbines basically, and grow some seaweed on them. And so I think, for me, that’s pretty exciting. And that’s definitely something that we need to figure out. Because if we’re going to be investing in this industry on a large scale, and figuring out how it’s going to not compete with other marine uses is going to be a big challenge. And I think an integrated way is going to be the best use of marine space.

Tim Hughes  34:39

And what sort of size of those farms in China the the bigger commercial spaces, what sort of area are we talking?

Scott Spillias  34:46

I mean, off the top of my head, but couldn’t give you an exact figure, but they’re very big. So some bays are completely full of seaweed farms and in many cases, it’s not just seaweed farms, but it’s also I like bivalve farms, and sometimes fish farms. But yeah, certainly you can. You can go on Google Earth and look at some satellite images and zoom in on some coastal areas of China, and they are just absolutely full of seaweed farming. Right. Right.

Gene Tunny  35:16

Wow. And what about in Australia? Where could we grow seaweed? Scott? Yeah. So

Scott Spillias  35:22

when Australia those in our analysis, we find that Australia has a very large amount of potential certainly compared to other regions. Some of that might be a bit biassed just by the species that we actually incorporate into our analysis. And also could also be biassed by the fact that we rely on historical observance of observations of seaweeds. And so there’s a lot more kind of science and recording of those kinds of things happening in places like Australia and Europe and the US. But that being said, yeah, there are lots of places and I think we could probably, you know, there’s heaps of different endemic species of seaweed here in Australia. And like I was saying before, there’s a huge variety of seaweed species with a huge variety of uses. And I suspect that for almost anywhere, any coastal area in Australia, you could find a seaweed that would probably grow there. Whether or not it’s the right seaweed that you want to grow for your given market or anything like that may not necessarily be the case. But there’s a lot of seaweed species here and a lot of a lot of coastline. And not just coastline, but a lot of space in our exclusive economic zone. If we can kind of crack that nut of building offshore farms. So yeah, lots of potential. At the moment. There’s a lot of research happening in Tasmania, where I’m based now into growing seaweed, South Australia. There’s a lot in Queensland, it’s starting to pick up there’s a few in New South Wales, but it’s definitely starting to pop up all over the country,

Gene Tunny  36:50

Ron, and once the seaweed that’s been produced in China, so what’s that been used for? What is it being used for food and how and how is it processed? How is it prepared? And I mean, what does it taste like? I mean, if you can tell us something about that. I mean, that’d be great. Yeah.

Scott Spillias  37:08

I haven’t been to China myself yet. But yeah, pretty sure most of the seaweed that’s being grown in East Asia, a lot of its being used for food. So things like noise. So when you buy, you know, your sushi or whatever, that’s probably some of that’s coming from China. Probably some of it’s coming from Korea and Japan. But yeah, I think globally, food is still one of the main uses of seaweed biomass. If you look at places like Indonesia, where the seaweed industry has grown dramatically in the last couple decades, a lot of that seaweed is actually being used. A lot of the biomass is being used for the hydrocolloid industry. So not necessarily for food, per se, but it’s being processed, and kind of thickeners. So like Carageenan are being extracted from it, and used and sold on for incorporation into other processed things. What does it taste like? Yeah, I mean, yeah, like I was saying, there’s lots of, there’s lots of different seaweed species, and they’re all pretty different. And so they’re all processed in different ways and can be used for different things. And I think, for me, that’s what’s really exciting about all this is that, you know, when we think about seaweed, we think about seaweed, as this one thing that really, it’s this huge, diverse group of things. And I think it’s this diversity that we haven’t really, fully come to understand, we have a pretty good understanding of the diversity of terrestrial crops, and things that we can use terrestrial crops for. And I suspect that seaweeds could be just as diverse and certainly if we put in the time and investment to develop, and domesticate different seaweed species, then we might find that they can be incredibly useful for a wide variety of things.

Tim Hughes  38:49

I was gonna ask as well, Scott. So you mentioned there’s a diverse range of seaweed? Do they have a similar sort of macronutrient build up? Or are they all very, very different, but primarily with proteins and say, omega threes, you know, some of these quite expensive, macronutrients to, to grow or to farm on terra firma? What does the macronutrient look like? In seaweed generally?

Scott Spillias  39:17

Yep. Yeah, that’s a great question. Yeah. I’ve only looked specifically at that we use 34 species in this recent study. And we looked at the nutrient profile of those. And we found there to be a huge amount of diversity in those 34 species. And so I suspect, if you were to look at even more than the ones that we looked at, you’d find just as much diversity and it’s also one of those things where, even within a single species, there’s probably going to be a huge amount of diversity just based on the conditions that it’s grown in. The nutrients it has available to it, how much sunlight it gets, things like that. Yeah.

Tim Hughes  39:55

For instance, with in going to windy this algae farm So, that have been done commercially. And omega three is one of the main sort of

Gene Tunny  40:07

that’s the aspirations, right? Yeah. trialling it at the woods group is trialling at the moment there, which

Tim Hughes  40:14

is great. And I’d be able to get that from a plant essentially, or allegations. So the potential for farming for these, you know, harder to produce macronutrients protein, definitely a big one would be a huge benefit, obviously, the the impacts of farming for beef and chickens, etc. That’s one of the issues that the seaweed potentially can help with. And I saw that there was a 2.6 billion tonnes of co2 removed, or that has the potential to remove 2.6 billion tonnes of carbon dioxide from the atmosphere per year. Is that right?

Scott Spillias  40:53

Sort of so in our analysis, that number is coming from we looked at what would be the mitigation potential compared to a baseline of feeding every ruminants on Earth with this diet that incorporated asparagopsis, which is the red seaweed that recent research has shown if you include it in the diets of ruminants, it reduces the amount of methane they emit. Right? Okay, we should definitely treat this number with a lot of caution and understand that, that is a would be a logistically, very difficult thing to do. And, you know, just remembering that, it’s, first of all, it’s gonna be very difficult to grow that amount of seaweed, even though it’s a relatively small amount, especially compared to the other scenarios we looked at. We definitely difficult to grow that amount of seaweed, but then also, just bringing that seaweed to livestock can be difficult, remembering that a lot of livestock doesn’t spend most of its time within feedlots where it can be easy to administer kind of special diets. That also number also comes from this fact that we project that to 2050 and compare it to a baseline scenario. And so in the baseline scenario, we’re expecting that ruminant production will increase drastically over today. And so if there are changes in kind of the amounts of, you know, the rate at which we’re consuming livestock or anything like that, that might change.

Tim Hughes  42:18

Yeah, yeah. Yeah. Cool. Thank you.

Gene Tunny  42:20

So yeah, it’d be good Scott, just to get a sense of what you modelled and the other shifts the changing pattern of consumption. So are we changing? So humans? Are we changing what we eat? Are we substituting are we bringing in some seaweed? And then we’re, we’re taking out some, some beef or poultry, we’re replacing that. And then, I mean, I understand the what’s happening with the cattle. But you know, what’s happening with humans in terms of our diet? What are you modelling?

Scott Spillias  42:55

Yeah, thanks for asking. Yeah, we, it’s a pretty simple shock that we incorporate into our model, we basically assume that every person on earth will consume seaweed out of it, right, or about 10% in their diets. So that’s a huge increase over what most of us certainly in the western world are, are consuming. People in kind of East Asia, probably eat seaweed at the highest rates, and even the probably the maximum would be somewhere around 2%. And so, you know, that obviously represents a huge increase. And we, we justify that in our in the research by making the case that I’m certain we could all incorporate more seaweed into our diets. And that could be kind of raw seaweed kind of in the same way that you would eat it in sushi, right? You’re actually eating seaweed itself. But it could also be if seaweed is used as a feedstock in some sort of industrial process in the same way that we use corn or soy, where we grow those things, and we break them down into their constituent nutrients. And then we incorporate that into a variety of foods. So just like, you know, you go to the grocery store, and you buy, you know, some packaged food, now thinking that it’s full of corn, but actually, it’s like 90%, corn, you know what I mean? And so, if seaweed were to be incorporated in that way, then we suspect that we could get up to higher rates of inclusion in our diet, so wouldn’t necessarily need some sort of cultural shift. But it would require kind of the economics to align. And also those, those processes to be developed to make that possible. Yeah.

Gene Tunny  44:31

And what did you find about the economic Scott? I mean, how in terms of cost per calorie, how does seaweed compare with other with other foods? Are you modelling an improvement in a reduction in that cost over time? How have you modelled that plays?

Scott Spillias  44:49

Yeah, great question. Yeah, we actually, we declined to do that. So it’s a it’s a very simple, a very simple modelling exercise. So we didn’t want Don’t make any assumptions about that just because we didn’t want to make any hard assumptions about we had to make an assumption, of course, because because there is going to be such a diversity in terms of where the seaweed is grown, what kind of seaweed you’re growing, the quality of it, all those things. So we make the very simplistic assumption that in our model, at least, we make the very simplistic assumption that see, we will reach some kind of price parity with the things that it’s it’s replacing. Of course, that’s not going to be true. But that at least gives us a very general baseline from which to start to understand kind of some of these impacts.

Gene Tunny  45:36

Right. So at the moment, would it be more expensive? Is that?

Scott Spillias  45:39

Probably yeah, at the moment, it would probably be more expensive. And I think, certainly in places like Australia, yeah. But we suspect that as as we develop this industry, and it becomes more sophisticated than that price may come down. And it also just depend on to what extent governments around the world want to support these industries. And if they get subsidies, or in the same way that we subsidise farmers all over the world, in different places.

Tim Hughes  46:05

You mentioned corn before, Scott. So are we talking that this may be possible to replace some high fructose corn syrup? Is that one of the possibilities for seaweed?

Scott Spillias  46:17

I can’t speak exactly to that, because that’s not my area of research. But I suspect it could. And there are certainly lots of people who are researching with different things we can do with seaweeds. And we’re finding that they’re very versatile in terms of what we can use them for. We can turn see we did a whole bunch of different fuels, we can create ethanol from seaweeds the same way we can. Corn. So yeah, it wouldn’t surprise me if we can also create high fructose seaweed syrup.

Tim Hughes  46:45

And I just want to seem like a silly question, because we’re talking about seaweed here. But are there any freshwater varieties that may be viable options? Or is this all purely saltwater plants? No, yeah, that’s

Scott Spillias  46:56

a great point that there’s definitely there’s heaps of freshwater allergies. And again, that’s not my focus of research. So I don’t know. But yes, there’s lots of freshwater algae that could almost certainly be explored for these kinds of different applications. Yep. Cool.

Gene Tunny  47:12

And do you know if anyone is making ethanol out of from seaweed? Scott, are there any? Any?

Scott Spillias  47:21

I couldn’t say if there is a lot of commercial, commercially viable operations, but that it’s a very active area of research. Not just ethanol, but also like Bio Oil. And people are looking at making aviation fuel from seaweeds. Yeah. So yeah, there’s been there’s a lot of exploration happening.

Gene Tunny  47:42

Right. And so it’s got potential, because there’s just so yeah, there are so many places we can grow it, I suppose, aren’t there, if you think about it.

Scott Spillias  47:51

Yeah, and some spirits species are just very fast growing. And so you can get really high yields. And because there are so few inputs, depending, you know, if you’re in the right place, then you could get really high productivity, really high biomass.

Tim Hughes  48:07

Can I ask Scott as well. So Australia, certainly has had a history of introduced species wreaking havoc on the local landscape, introduce plants have just run riot and animals etc. are there any risks with seaweed, but the same kind of issues are being introduced to areas where there may not have normally been, you know, the impact on you mentioned before that the onScale? Clearly the be an impact of some sort. But as far as displacing natives, plants and native marine life?

Scott Spillias  48:40

Yeah, absolutely. That’s a very real and serious concern that we should take very seriously. There have been heaps of seaweed introductions all over the world that have led to exactly that. Even just this, this asparagopsis that is becoming very interesting and popular and exciting because of its anti myth, antigenic properties. A species of that has been introduced in the Mediterranean where it’s highly invasive. So I think any successful implementation of seaweed farming will be done using locally endemic species, and will not include spaces that are being shipped in doing that could be could run a huge risk when there are also examples of introduced seaweeds being cultivated safely. However, you know, you just run a huge risk in doing that to introducing things into the marine environment that could cause lots of problems.

Tim Hughes  49:38

And is there any governance internationally at this stage with with cultivating seaweed

Scott Spillias  49:43

in terms of like preventing those kinds of things? Yeah. The governance around this is pretty weak at the moment. I can’t I don’t know a whole lot about the international space. But you know, in Australia, I’ve spoken to a bunch of folks in the industry here and in government and it’s Generally recognise that there’s a lot of work that needs to be done in terms of getting the government governance in place. So that, you know, we’re making sure that we’re not running the risk of causing environmental damage, but also just making sure that we’re making it accessible for people to get started in this industry. I’ve also heard from people who are really interested in growing seaweed in whatever place they are, and they’re finding that there’s just so much red tape associated with it. And even just in Australia, state to state there’s a lot of there’s different regulations, you know, I don’t think necessarily that we should make any kind of fast track kind of thing for putting seaweed farms into the environment. Because I think we do need to be very cautious about where we’re putting them. And I think there are going to be places that are going to be much better than others. And there is damage that can be done from farming seaweeds in the marine environment. But I think we do need to make it possible for people to get involved. And I think there’s a lot of potential for good to come from them. So hopefully, we can start to introduce or just get our heads wrapped around how we can allow people to get into the market.

Gene Tunny  51:08

So Scott, the takeaway from your study, is it that, and this is from a UK, the UQ media release. So basically, it says expanding global seaweed farming could go a long way to addressing the planet’s food security, biodiversity loss, and climate change challenges. So I understand the food security, because there’s another potential food source, climate change challenges. Well, that’s from the seaweed being used as feed for cattle. What’s the How does it prevent biodiversity loss,

Scott Spillias  51:46

basically just comes from the assumption that if we’re, if we’re farming more in the ocean, then we hopefully won’t need to farm as much on land. And so we already know that land use change is one of the main drivers of biodiversity loss on lands when you change, of course. So if we can relieve some of that pressure, then hopefully we can maintain some of those last remnants of pristine habitat for land. ecologies, that’s that’s also a strong assumption that we shouldn’t. We should also question, you know, if we’re growing lots of seaweed in the ocean, there’s no guarantee that we’ll be growing less things on land. But we’re hoping that that’s what does happen. But we also need to be careful about, you know, growing seaweed in the ocean, we’ll also have biodiversity impacts. This is a hotly debated topic at the moment in the space and the extent to which seaweed farms will provision habitat for marine organisms. I think most people accept that seaweed farms will be their own unique habitat, which may harbour some things, certainly things that grow on seaweeds, but those aren’t necessarily going to be valued by people who are growing or farming the seaweeds. You know, if you have fouling, you have little things growing on your seaweed that could decrease its quality as a as a product. But then there’s also the hope that, you know, if you have lots of seaweed growing in the in the marine environment, it could be habitat for fish, which could improve fisheries. But we haven’t really come to a firm conclusion on the extent to which that happens. And also, it’s just going to depend on where you put these seaweed farms, you know, if you’re putting a seaweed farm in a highly productive area, that’s a place that’s already highly productive, it’s probably going to make it a little less productive, because it’s seaweed farmers are going to be a simpler kind of ecosystem in the same way that, you know, a tree plantation on land is a simpler ecosystem than an old growth forest. But if you’re putting a seaweed farm in a place where there’s not a lot going on already, then it could, it could provide some biodiversity benefits. So there’s definitely a lot more research that needs to be done in that space.

Gene Tunny  53:54

Right. And one final question for me is, is seaweed more climate resilient? That I know there’s a concern that with climate change that will affect the yields of some crops? Is, is this a reason that we might want to switch to seaweed? Yeah, that’s such

Scott Spillias  54:11

a good question. That’s something I’m really interested in. And I don’t have a good answer for that, either. i My suspicion is that might be the case. At this point, it’s just speculation. And that’s something I’d really like to look into further. You know, when I think about some of the main threats from climate change for our food systems, you know, thinking about droughts or thinking about floods, both of which have major implications for growing crops, neither of those things are going to have much impact in the marine environment. If you have a food system that’s diverse, that incorporates terrestrial production and marine production, my feeling is that that’s going to be a more resilient food system all around. So because if your crops on land are suffering, maybe you have your crops in the ocean that are doing okay, now, there threats like marine heat waves can impact seaweeds negatively their diseases, seaweed diseases that are exacerbated by rising temperatures. But but same so if we have a marine heatwave in the ocean that’s affecting our marine crop that maybe there’s a, we have a chance that our terrestrial crops are doing okay. So my feeling is that having more diverse food systems will provide climate resilience. That’s not to say necessarily that seaweeds are more resilient than terrestrial crops. But I think the combination of both is the key here.

Tim Hughes  55:30

I see on that note, Scott, I know, historically, they’ve been kelp forests disappearing from a lot of places where they’ve been for many, many years. Is there an opportunity with this research to replace or replenish those kelp forests?

Scott Spillias  55:45

Yeah, there’s a lot of research going into that right now. Here in Tasmania, that’s very, very active, hopefully, I guess is the short answer. Yeah, we know that. Warm water is not good for many kelp species. And that’s why we’ve lost a lot of kelp. But we also lost a lot of kelp to other kind of human pressures. But yeah, we’re there’s a lot of research into that space, since hopefully, we can keep kelp kelp forests into the future.

Tim Hughes  56:09

Yeah. It’s it’s great research. And it was one of the things he had going back to your original remote, trim it to the article is, it’s so good to see. Yeah, well, we might be able to get a more diverse range of food and is potentially a very healthy food as well, like, you know, it’s a natural, it’s a natural plant. Really interested to see what happens next. So where can people go to find out more about this guy?

Scott Spillias  56:36

So yeah, I would just say keep an eye out for the news. There’s a lot of really exciting work being done in this space by not just me, but many other collaborators, University of Tasmania is doing a lot of really interesting work. That’s the thought I guess all I would say on that. Well, we’d

Tim Hughes  56:49

love to have a chat in the future as well as things develop, because it is a really interesting space. And yeah, it’s, you know, we wish you well with it, because I think it’s a really a great area to be researching. And hopefully, it’ll come to some kind of commercial fruition at some point not too far away. Yeah,

Gene Tunny  57:07

I was just, I was wondering, just finally, another thing occurred to me with the harvesting of Scott, how do you do that? Is that by hand? Is it manual?

Scott Spillias  57:17

It’s done in a few different ways. I think, these days, a lot of it is being done by hands too. Yeah, I think there’s probably a lot of room for improvement or automation in that in that in that area. Just off the top of my head. I’m just thinking about where how it’s done in different places. And yeah, for the most part by hand.

Gene Tunny  57:37

Yeah. Yeah. It’s just interesting. I might look into that, too, because of how that affects the economics of it. It’s fascinating and yeah, okay. Well along. Yeah, that’s great. Scott. Yeah, really appreciate your time. Tim, did you have any other question? No, that

Tim Hughes  57:51

was it. I really appreciate your time with this. Scott. I know you’ve had this conversation a few times. You’re very prolific with your, with your media requests. So thank you for granting us are one and yeah, really looking forward to hearing more?

Scott Spillias  58:06

Oh, it was absolutely. My pleasure. Thank you guys. So much really interesting. questions and conversation.

Tim Hughes  58:11

Cool. Good. Thank you.

Gene Tunny  58:12

Okay, thanks. That’s good. All right. Hey, thanks for listening to this episode of economics explored. If you have any questions, comments or suggestions, please get in touch. I’d love to hear from you. You can send me an email via, or a voicemail via SpeakPipe. You can find the link in the show notes. If you’ve enjoyed the show, I’d be grateful if you could tell anyone you think would be interested about it. Word of mouth is one of the main ways that people learn about the show. Finally, if your podcasting app lets you then please write a review and leave a rating. Thanks for listening. I hope you can join me again next week.


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