9. A lemon-powered spaceship

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BBC Sounds, Music, Radio, Podcasts.

I'm Hannah Fry.

And I'm Dara O'Brien.

And this is Curious Cases.

The show where we take your quirkiest questions, your crunchiest conundrums, and then we solve them.

With the power of science.

I mean, do we always solve them?

I mean, the hit rate's pretty low.

But it is with science.

It is with science.

We are joined today in the Curious Cases studio, not only by me and Dara O'Brien, whose drink you can hear clanking in the background, but also by two pieces of fruit.

Yeah, I was going to make them add them to the cocktail, but I can't now.

Are they for scientific purposes?

I believe they are.

Did you ever make a battery out of these when you were a kid?

You're waving an orange at me.

I am.

Sorry, this is radio, isn't it?

Yeah.

Forget these details.

You can hear the noises, but can't see the pictures.

I did not make a battery out of that.

Sorry, I'm always terribly afraid of landing Ireland in any kind of stereotypical stance, but the potato thing we did, where you make a clock out of a potato.

A clock?

Yeah.

Yeah, you can put, like, I mean, because this is the acid, isn't it?

And now that I say it, it seems so much more obvious that we should have used lemons, but lemons clearly not as available when I was a child.

Their mainly used was a scurvy thing.

Yeah, you can make a clock out of the acid and potatoes.

Sorry, I mean, I'm with you on the whole vegetables being batteries, etc.

Yeah, yeah.

But the clock element?

Oh, yeah, like a digital clock.

It just needed a small amount of charge.

Right, so you actually need the electrical component.

No, no, I wasn't building like it wasn't like a chronograph.

It wasn't like we used a sundial.

Yeah,

we'd carve it into an arrow and then we'd place it so the shadow fell.

Didn't you want to hold it out?

Didn't everybody make, you know, did I make the pieces of a precision Swiss watch out of Potato and then put them all together?

Yeah, no, you're right, you really have done wonders for the stereotypes of Irish culture.

That's annoying.

Okay, all right, so we should have used citrus, but who had citrus in Ireland in the 1970s?

That's what you mean.

Like using the acid, is it?

Yeah, you can make batteries out of lemons, which is essentially what this programme is about.

But particularly, we had a really sweet question come in from Elijah Thomas who wants to know how many lemons would it take to power a spaceship oh wow this is gonna be a big number isn't it I hope so I mean if we find out it's just four

like four lemons that would be I think it sort of surely depends on the size of the spaceship you know

When you are confronted with a quest like this, of course the person to call is our old friend Randall Munro, the author of a book full of serious scientific answers to absurd real-world problems.

Hi.

Hi.

Hi.

Randall.

Okay.

Have you ever made any fruit-based batteries yourself?

No, I haven't.

I know it's a really common experiment in middle school chemistry class, but it was one of a couple of different things where I always heard about people making these for class, but no one ever told me, all right, this week your grade is based on if you can make a lemon battery.

I also didn't get to do a volcano that erupted baking soda and vinegar.

Feels like you missed out on a significant portion of the fun part of science at school.

Yeah, exactly.

But they still did make me dissect animals, which sort of put me off science a little bit for a while.

Because I think the dissecting animals is pan-cultural.

That goes across the globe.

Oh, no,

there was talk of it in our school, but there wasn't like a supply of frogs.

But the exploding volcano thing is such an American science fair thing.

And it must be because I grew up in a very geologically quiet region.

Like at no stage do they want to train kids to make models of volcanoes.

I don't think I'm going to do that either.

Thus far, I'm on zero out of three.

All right, so we asked you the lemon-based science question, though, Randolph.

Anything that you can offer to help us?

Well, because my background's in physics, I'm always inclined to think about things in terms of what amount of energy is available.

So if we're talking about using a lemon to provide power, you can throw them.

You can eat them.

Lemons have calories.

Not very many.

Not a lot of people eat enough just raw lemons to get calories from them, but the calorie energy density is pretty high.

You can burn a lemon if you manage to dry it out and get quite a bit of energy out of it that way.

And so I usually like to think about just a big picture, how much energy is here and then what are the ways to get at it.

I'm quite liking the direction you're going with this.

Although for a moment there in the middle, I thought you were going to suggest that we have an army of people, feed them exclusively on lemons and have them hurl the rocket into space.

Is that

I mean, you can calculate how efficient that is as a process.

It's easy to look up.

Sure, you could figure out.

If a person eats this many calories, they're doing this kind of exercise.

Here's how much work they can do.

You can figure out the calories in a lemon.

That's easy to look up.

You can chain all these numbers together, and you'll get an answer.

That's like, here's how many people pedaling could charge up a battery or pull back a spring and launch something.

That's one of my favorite things about science and about mathematics: is like the physics doesn't care if the question you're asking is ridiculous or not.

It provides you a way to get to the answer.

Whether it's ridiculous or not is a judgment that's up to you.

Have you done these kind of calculations before?

Not with a lemon specifically.

But in terms of how many people.

Yeah,

I almost feel like muscle power is something where the limitation is not usually the chemical energy.

It's the ability to convince that many people to work together.

How do you convince people to pedal on a bicycle, to run a mechanism while eating only lemons?

That feels like a management problem that's way beyond my ability to tackle.

Okay, so I don't know if we're going to go down that route.

I don't think we ever considered it.

I mean, my go-to was this is like a battery like you'd have in the gift shop of a science museum, that this is essentially what we're going for.

But the idea that we're just regarding lemons as a store of biomass in some way, that it just seems to be that we are in some sort of situation where all we have is lemons and a rocket and we have no more efficient.

This sounds like a dystopian view of the future.

Yeah, I mean, can we bury the lemons and have them turn into oil?

I mean, if all we're doing is any kind of thought experiment, then surely there are other ways we can create sump from our lemons and then process it into something explosive.

I mean, this is very true.

But okay, let's go back to the original sort of science experiment style.

Because, luckily for us, we have current Guinness World Record holder for highest voltage from a fruit battery, Professor Seiful Islam, who's here with us in the studio.

And a slightly, I feel desperately more, a really good job title, by the way, but just doesn't quite have that air title.

Yeah, Professor Paul Shearing from the School of Engineering Science at Oxford University.

See, that's great.

It just doesn't have the Guinness World Record stamp on it.

You research into emerging battery technologies, which often don't include lemons.

That's right, yeah, we do all kinds of flavours of different batteries, but they're not lemon-flavoured most of the time.

Is there one definition you'd give, what defines a battery?

Yes, we need two electrodes and an electrolyte.

So bit of science jargon in there, but we need a positive electrode, a negative electrode, and something in between.

Yeah, when you look, you get a battery and you plug it in, you see whether there's a plus and a minus, and you know that something is running from the plus to the minus to the minus to the plus.

But what's happening inside the battery?

Because I suppose as a kid, I just presumed everything is in one end there's nothing in the other end and it desperately wants to balance that out so all the electrons will run on the cable and they'll light your your bulb or they'll power the toy car or whatever inside that battery they've got ions moving from one electrode to the other and there's a chemical reaction going on from one side to the other in a primary battery like the double a in your remote control it just goes one way in a rechargeable battery in your phone a lithium-ion battery that can be reversed.

So it's like a shuttle between the two electrodes.

So actually, when you say what's inside, there's a good chemical reaction.

I think lithium is a really nice one because it's the smallest and lightest metal ion in the product table.

Basically,

it loses that one electron, goes round, that lithium-ion itself now, it's lithium plus, it's lost that electron, that now moves across from one electrode to the other.

So the negative bits going one way through your device, the positive bits going the other way through the battery.

Exactly, yeah.

Do they meet up again then at the other end?

Yes, in essence, yes.

Hey, pal, how are you doing?

Haven't seen you.

I've had a long, old journey, right?

Exactly.

Exactly.

They meet up at the other end.

What's lovely is that when you plug in your phone, you want to give it some more electrons, and that pushes the lithium-ions back the other way.

Ready to start the journey yet again.

Yes.

I like that idea of them both being at the edge of the battery and being like, okay, it's a race.

Ready?

Go.

You go your way.

I'll go there, Ace.

I'll get some stuff done that I'm not even sure is happening.

I'm totally unaware of it.

But when I come around, we meet up again, and there we go.

Yeah.

Okay, that's a much more vivid way to think about this.

But a lemon?

So if we take one lemon, and it doesn't really matter how big it is, you still end up with about 0.8, 0.9-ish volts, so a little bit less than one volt.

And you've got your two electrodes, so we've got a copper electrode, and we've got a zinc electrode.

You could use different types of metals, but we've got zinc and copper here.

So in this particular example, one electrode is losing electrons, and the other one is gaining them.

And so when we've got got the race around the circuit, it's the electrons that are being lost from one part and they're being gained by the other part.

So in the case of the lemon battery, we've got electrons that are moving to and from the electrodes, and we've got protons in the juice of our lemon, in our electrolyte, that's moving between one and the other.

So you've got a race between protons and electrons in the case of our lemon battery.

Do they also meet up the finish line again?

Not quite as neatly as the case of the lithium-ion battery, because it's a bit more complicated.

In the case of the lemon, what we actually do is we have a reaction at the zinc electrode which involves the zinc, but at the copper electrode what we're really doing there is we're evolving small quantities of hydrogen.

So you've got some protons in your lemon, in the acidic lemon.

Protons being the hydrogen.

Yeah, a hydrogen plus atom.

So atom of hydrogen which has lost an electron and therefore it's become positive.

So H plus is a proton.

So we've got lots of these H H plus protons in our acidic lemon.

And when they arrive at the copper electrode, they pick up that available electron, which is raced around the circuit, and then they generate a really small quantity of hydrogen gas.

So if we had a tiny little microscope, we might be able to see bubbles of hydrogen picking up.

That's great.

That's lovely, so.

But lemons themselves, I mean, it's not like they're not electrically charged, they're not sitting there buzzing with electricity.

When we put them into a circuit, that creates the whole thing, it creates this reaction.

We need these two dissimilar metals and the full circuit and the acid in the lemon.

Bring them all together and we've got a very basic battery.

And a very, very low power battery as well.

Really low power, yeah.

So again, if we get the voltmeter out, we can measure the voltage, we can measure the current, and from that we can calculate the power.

It's a really small amount.

How many lemons does it take to power up a little calculator?

So the little calculator that I've got in front of me, which is a really basic sort of...

desktop calculator would normally take one aa battery but if we want to do it on lemon batteries we've got to have three of them okay so can we just keep adding more lemons?

We did, yep.

Tell us about this world record.

I was invited and very honored and surprised to give the Royal Institution Christmas lectures.

And in one of those lectures, we're to talk about energy storage.

And we demonstrated that with a classic school experiment, a lemon battery.

And we wanted to show how a battery worked, and you can stick in a copper electrode and a zinc electrode and generate a voltage.

But I didn't want to use just three lemons to power a calculator.

We wanted to go very large and we did go very large we bought 1600

lemons we cut them in half and we generated 1400 volts based on that so that was a world record at that time I should add that two years after that a group in Denmark broke our record so I wasn't feeling bitter or sour about that but we the Royal Society

sorry Royal Society

approached me before COP26 said Seifel we want to do something around energy.

And I said, I want that record back.

So we then used 3,000 lemons and got to 2,400 volts.

But as we've just stated, the amount of power is minute.

That generated only two watts of power.

I mean, less than an ordinary light bulb.

But

I have got the world record for the...

highest voltage from a fruit battery.

If you ran your calculator off the lemons for a few hours, a few days, a few weeks.

the inside of the lemon, what's the plan?

Is it just not acid anymore?

Well, that is a good question.

And actually, one of these mankey old lemons that's sitting in front of me is an experiment that I did at the weekend, and you can see that the lemons become really kind of discoloured.

And if you were to look at the electrode as well, the electrodes become pretty mankey as well.

So they don't last for a very long time.

So you get a small amount of power for a really short amount of time.

So they don't make the best battery of the world.

This is not looking good for a dystopian future of eating only lemons.

Oh, yeah, just getting to that space shuttle as well.

Yeah.

Hang on, why lemons, though?

Are lemons the only fruits?

No, you could use oranges,

you could use a potato.

It doesn't even have to be a fruit.

I mean, the good thing about lemons and limes and oranges is that they're, as everyone knows, quite acidic.

So actually, that acid environment that we would think of as being a good electrolyte, obviously we find inside the citric acid in a lemon.

What about a pineapple?

Could do a pineapple.

I tried it with a strawberry at the weekend.

That worked pretty well as well.

So, yeah, I mean, anything that's got some level of acidity and those protons available,

you can make a batch.

Well, it's sour sweets, you know, those

tank fastics.

Yeah, tank fastics.

Or those toxic sludge those ones that kids.

Probably, you might

maybe sort of grind them up and dissolve them in some water if it was

acidic, yeah.

I think, Randa,

a future where everyone can only eat fizzy sweets is

probably gonna solve your management problem.

Yes, and my stockpile of sour patch kids will finally be useful for something other than rotting my teeth.

Right, you worked at NASA for a while, so you have been there when these spacecraft have been launched.

So do we have any idea of how much power we're talking about here?

The interesting thing is that powering a spaceship itself does not necessarily take a lot of power.

There are a number of spacecraft right now, and many of them use ion engines.

And those are very low power.

You're just sort of shooting electrons or charged particles off into space, but you can run it for a long time using the solar panels, and they'll produce just a very small amount of thrust.

But small amounts of thrust over a long time is plenty to get yourself around the solar system.

The big problem is getting off of the surface of the Earth.

Because to do that, you need a whole lot of power really quickly.

Because if you just do a small amount of thrust for a long period of time upward, you're not going to go anywhere.

People talk about building giant cannons, space elevators, this project involving propelling spacecraft with nuclear bombs, but all of those are still theoretical.

Because chemical rockets, rockets, the fuel we use, kerosene, which has about the same energy density, I think, as some dried foods, those fuels have just more energy density in a smaller amount of space than anything else that we can build a rocket with.

Even with the high energy density of rocket fuel, we are barely able to get rockets into space.

You see a rocket sitting on the launch pad, and most of what you're looking at is fuel tanks because the rocket is mostly fuel and only a small payload.

I was thinking about this recently that like if you have a planet that had just surface gravity that's twice as high as Earth's and there are planets like this that we are finding in other solar systems now, a planet with just surface gravity just a little higher than Earth would make chemical rockets not just hard, but maybe impossible to get off the surface with.

So how much Paul, for example, has how much power does a typical spacecraft use?

So I did a bit of googling, looked up on NASA at the space shuttle, which has obviously now been retired, but according to NASA, 44 million horsepower, which you can convert to watts or kilowatts, but yeah, 44 million horsepower is what it takes to get the space shuttle off the ground.

So we know what it is in horsepower.

What is that in watts?

So 44 million horsepower is about 32, 33 million kilowatts.

Kilowatts, okay, so that's 32 million thousand watts.

That's that's right.

And then the other figure we had for watts earlier on was for 3,000 lemons, you created how many watts of space?

Just two watts.

Two.

Okay, I'm going to write those two narrows down.

I'm going to put a greater than symbol between them because 32 million thousand watts is bigger than two.

Yeah, yeah, by some distance.

Yeah.

Just for anyone who's a bit rusty on their mentality.

Yeah, yeah.

So how many lemons is that?

So back of the envelope calculation, I reckon it's about 138 trillion.

Oh, okay.

Okay, how many lemons are there in the world?

So I also looked this up as well, and I reckon, according to some statistics website, there are about 21 million tons of lemons that are grown every year.

And if you think that every one of those weighs about 50 grams, it means that we need 329 years worth of lemon production.

I think it's worth it.

I think let's do it, everybody.

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Randall, can I come to you on this?

If we decide as a planet to move all of our production to lemons,

can you foresee any other problems with this?

No, no, I think that sounds like a great idea.

I tried taking, there's that miracle fruit that you can get that makes sour things taste sweet.

It's like a tablet that dissolves.

I tried that, and if you do that, you can eat a raw lemon and it tastes okay, but I think it's still not great for your teeth.

The only way I've enjoyed eating pure lemons is when they're like candied or caramelized and you know you've added a fair bit of sugar to them.

So I would think you're going to use a large chunk of the planet for growing lemons, but we also, I think, we want some sugar cane or some other, you know, sorts of sugar so that we can add that to the lemons and make them more palatable.

Because if I'm eating lemons for 300 years, I'm going to have to add a little bit of seasoning to them.

Surely sugar is more energy dense than lemons.

Yes.

Yes.

We're not proposing, I don't think, Randall, that you eat the lemons.

It's just 300%.

Oh, no, no, no, no, no, no, no, no, no, no, no, no, no, it's worth your lemons in order to power our space.

So I'm concerned.

I know that these lemons are being grown for use in

but if you've given over all of the world's agriculture to growing lemons, you're going to have to start eating it.

The people, those of us who are working on the project, at least,

are going to need to eat something.

I mean, look, you wouldn't have to.

We should be pictured regularly, happily munching on lemons.

You can use a fraction to have some gin and tonics just to keep the

that we got a section of the quinine production.

How much of the planet should we give over to tequila?

That's right.

Yeah.

This is all well and good, but there is a slightly more serious point here because we were talking about kerosene earlier.

How are we going to power rockets and spaceships in the future when we're trying to move away from that type of technology?

That is a really good question.

And batteries are wonderful.

They're good for lots and lots of things.

You know, see more electric vehicles on the road powered by lithium-ion batteries.

People increasingly are looking to how we can use lithium-ion batteries, maybe in things called E-V-TOLs, which are electric vertical take-off and landing vehicles.

They're like electric helicopters.

But actually even an electric helicopter needs a lot less power and energy compared to a space rocket.

Getting a space rocket launched and out into orbit is one of the most energy-intensive activities that we can possibly imagine.

It's going to be an awfully long time before we get any type of electrically powered rocket, let alone one that's powered by Lemon batteries.

But we will see batteries in other aerospace applications.

So actually people send up batteries all the time to the International Space Station.

So once you're there, it's the batteries accepting the energy from the solar panels on the International Space Station that keeps everything working.

Every satellite that we have up in orbit, they've got batteries on board.

When we've got Mars rovers, they take up batteries with them that can then keep them running during the time that they're roving around on the Martian surface.

But in terms of the primary power for a space rocket, I think it's going to be rocket fuel for a long time.

What is the problem here?

Is it that you could do it with batteries, but they'd just be too big to be able to take off?

You get into this kind of vicious circle because you need a lot of energy.

So then you've got a lot of batteries, but the battery is way too much.

And because you're carrying all that extra payload, then you need even more batteries, et cetera, et cetera.

And you just don't get close to the type of energy density.

So we would measure energy density in watt-hours per kilogram, so the amount of energy that we store per unit weight.

And you just don't get close.

You're at least an order of magnitude, maybe a couple of orders of magnitude lower in terms of current sort of cutting-edge battery technology than you need to be.

So wait, what do you get from lithium-ion batteries?

Well so lithium-ion battery that you would get in a vehicle would be about 250, 300 watt hours per kilogram.

Kerosene I think would be about 20 times higher.

I mean we've seen drones tick off

on batteries.

A personal jetpack type thing would that work with electric power?

So you're right, yeah we get lots of drones and you know you can buy like toy drones from

wherever and they're getting bigger and bigger and you're getting surveying drones and I think that people have demonstrated actual passenger helicopters powered by electricity.

Jet packs, I don't, I've not seen one.

The ones that I have seen actually have small handheld jet engines which look terrifying right?

You've literally two jet engines and you're pointing them at the floor.

But in terms of ones powered by electricity, I've not seen any.

If you look at the really small like trainer aircrafts that you see in little airfields sort of buzzing around, Historically they would be powered by piston engines, but you can buy now off the shelf almost electric powered fixed wing one or two seater planes and actually as the battery technology gets better and the airframes get lighter and lighter we see more and more of those applications in aerospace so it's it's not just helicopters it will be fixed wing planes and they're getting bigger and bigger but we will hit up against a bit of a limit in terms of how heavy the batteries are and how big the plane can be.

So is our limit say when we get to jumbo jet type planes?

We're a long way from jumbo jets.

I think we'll get to a place in the not too distant future where you'll get planes that can fly London to Amsterdam for example but London to New York that's a really big ask that's an awful lot of batteries and an awful lot of energy and power required in that journey.

Could we have like solar powered planes?

So following on from what Paul just said, there are those same planes because you think of batteries as an energy storage device it actually stores energy.

So you could have on the wings and there have been some gliders we have the wings are solar panels and we mentioned the kind of satellites, mentioned the Earth station station above the skies.

Some of them have these massive solar panels and actually just storing energy straight into batteries.

So the combination of solar with batteries is quite exciting.

It's an area of research that I'm doing.

The technology, surprisingly, is there.

It's sometimes to do with economics, just to get the cost down.

But we want, obviously, the next generation is trying to convert more energy.

from solar from the Sun but also storing as much as we can in a smaller volume in a smaller mass, and that's the excitement.

Sometimes we are going beyond lithium-ion and going beyond what current technology is.

Well, I mean, frankly,

there's one thing I learned today, it's that lithium-ion is pathetic.

20 years old.

You can't say that.

You've got looking at a laptop there and you've got your own mobile phone without those.

There's a lot of headroom though before we get to Kerasi.

That's what I'm hearing.

When you say we're getting there with this technology, do you think there will be one day where you can sort of jump on a solar-powered flight?

I think in the near future unlikely, but who'd have thought, let's say, 20 years ago, that all of us would have not a mobile phone, but a mini supercomputer almost strapped to their left or right hand.

So in terms of advancement, that has been disruptive technology, and we couldn't have predicted that.

And that still uses the rubbish lithium-ion?

Yes, that still uses the rubbish-lithium-ion.

But is the model that we should think of probably like hybrid cars, something that would alternate between the two sources?

You've got solar panels on your wings.

Once you're in flight, can you, could you operate the internal services of the plane on that electricity?

It's important here to distinguish between what's possible in a kind of demonstrator prototype and the sorts of planes that one of us would get on at Heathrow Airport.

In the sense of, you know, a prototype that has solar panels on the wing and a really lightweight battery, people have done this.

They've done really long flights with lightweight batteries, big solar panels, enormous wingspans on these planes.

But it's not something that I would willingly strap myself to, and it's certainly not something that we're going to get 300 passengers from Heathrow to JFK on.

So there's

a really...

Strap yourself to a space rocket though, to be fair.

Well,

I wouldn't want powered by 11 batteries for sure.

But yeah, so I think

it's a question of distance, but also a question of scale.

And particularly in the aerospace industry, as you would expect, there's a huge safety concern there as well.

So they're a relatively conservative industry in terms of the technologies that they adopt.

But we do still need to to get better battery technologies in a hybrid form or in a pure electric form in order to start chipping away at some more of those aerospace applications.

And I will speak up for the lithium-ion battery because actually

I'm a big fan of the lithium-ion battery.

You have to consider as well that when you've got a fuel like kerosene or petrol, you're burning it.

So you have a really inefficient process.

You're burning the fuel to then put in the engine to then make the wheels turn or the engine move to fly the plane.

When you've got a lithium-ion battery, you're storing electricity, you're putting into an electric motor.

you have a much more efficient system.

So actually even though you say storing a lot less energy, you make the energy work much harder for the job that you're hoping it to do.

So yeah, I'll speak up for the lithium-ion battery.

I mean of course it's the best that we've got right now but we can do better in the future can't we Paul?

We're working on lots and lots of different flavours batteries and the wonderful thing about being in electrochemistry is you can look at the periodic table and think I can almost take pretty much any two elements in a periodic table, put them together, measure the potential, work out if I get a a good battery or a bad battery.

Lithium-ion is the current sort of champion technology, but we've got other batteries which we're exploring, like sodium-ion batteries, where sodium can be cheaper and more available, or solid-state batteries, or lithium-sulphur batteries, which have a higher energy density.

So, we're always chipping away at what the next technology will be.

And the wonderful thing in batteries is that matchmaking in the periodic table, we can think of lots more combinations.

Is all of this

a materials question?

There are materials we have yet to discover that could make these problems go away.

Materials are key for step advances.

We haven't always discovered the best materials.

Some of the materials that we discover aren't good enough or just too costly or even actually producing too much CO2.

Another thing to defend lithium-ion on is in terms of

the lithium-ion emissions.

If you look at battery experts, of course we're going to defend ourselves.

It's CO2 emissions.

You know, if you're burning fuel, I mean, you're just creating creating lots of CO2 emissions.

So there are a lot of factors in trying to discover new materials, but it is a big factor, is it materials discovery indeed?

If we're talking about being, you know, ecologically aware and odd, what did you do with the 3,000 lemons?

About five of them for gin and tonics.

The others, we went to a biofuel company and they used it for composting.

So they weren't wasted.

Good.

They weren't wasted.

And anyone who was wondering that for the entirety of the programme, you can now rest easy.

So I think we will, at this point, say thank you very much to our guests professor saiful islam professor paul sharing and randall monroe

i think we've sort of answered the question

yeah i think we we we knew the answer anyway we did no

um i think the answer is not a hard no it's just a very very very soft no okay you gotta give us 329 years to grow enough lemons then

close down all industry yeah just just entirely lemon based for the sake of one rocket yup which you know may or may not fail Yeah, yeah.

I mean, like, you know, I mean, I think sometimes things are worth getting behind, you know?

You know, I think it would be, you think it could be like a moonshot kind of moment?

It seems like a lack of ambition on your part, Darren, Brian.

Yeah.

What if it was potatoes?

Would you be more excited?

I would, because you can prepare potatoes like eight great ways.

Irish mixed grill.

No, I'm just saying, I'm just saying, a bit of dauphinoise, a bit of...

Not mash, not mash, but all the other ways are generally great.

I think you're absolutely right.

And I think that the great conclusion of this episode should be potatoes are

greater than lemons.

Greater than lemons and all less than kerosene.

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Hello Anne Brancock and I'm Robin Ince and we are back with a new series of The Infinite Monkey Cage.

Robin, in 15 seconds or less, can you sum up the new series of The Infinite Monkey Cage?

Yes, I can.

Do you want to learn how to win every single board game you ever play, including Monopoly and Cludo?

Do you want to know about alien life coming from Glastonry?

Do you want to know about The Wonder of Trees with Judy Densham?

And do you also want to know about the unexpected history of science with Rufus Hound and others at the Royal Society?

How is it unexpected?

I don't know, which is why it's unexpected.

It's unexpected to me.

It might not be to the listeners.

The Infinite Monkey Cage.

Listen first on BBC Sounds.

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