Horizon (1964–…): Season 50, Episode 12 - The £10 Million Challenge - full transcript

For 50 years, Horizon has
provided us with an insight

into the very best
of scientific discovery

and technological innovation
from around the world.

Our films have featured some
of the biggest names in science

and brought you the latest
advances in everything from medicine

to computer technology -
space science to biology.

As the 21st century marches on,
the world faces a whole new set

of scientific challenges.

To celebrate Horizon's
50th anniversary,

we're inviting YOU to get involved.

The question is,
if you had £10 million



to make one change to the world,
what would that be?

This week, a Prize Fund is launched
to help solve one key problem

facing our society today.

And we want you to decide
what that is.

We've put together a team
to help you choose.

From antibiotic resistance,
to carbon emissions from planes...

I wasn't expecting that!

..from our thirst for fresh water,

to our hunger for food
to feed the world.

They do provide a satisfying crunch.

And from the burden posed
by dementia care,

to the difficulty of life
in a wheelchair.

Everything I use
is in the lower cupboards.

Don't like wasabi! All the stuff
I don't like's at the top!



Which of these is most in need
of ten million pounds?

It's your choice.

And that's not all,
because if you or your team

are sitting on an idea
which could solve the problem,

that £10 million could be yours.

This is the Royal Observatory,
Greenwich -

a place of huge importance
in the history of science.

And it's where the story of today's
Prize Challenge started

300 years ago.

1714 saw the launch of
perhaps the most famous

science prize in history -
one that put Greenwich,

and British science,
on the map for ever.

Just like the new prize,

it was prompted by the need for
science to solve a grave problem -

one that faced every sea-faring
nation on earth.

300 years ago,
naval navigation was perilous,

because when they were out at sea,
far from any landmarks,

it was extremely difficult
for sailors to know precisely
where they were.

That problem caused one of
the most tragic accidents

in British naval history.

On one terrible night in 1707,
four ships sank

near the Isles of Scilly,
with the loss of over 1,400 lives.

The sailors died because
they couldn't work out

exactly where they were.

The hardest task of all
for any navigator was to work out
their longitude.

To calculate their position
around the globe, in theory

all they needed to know was
the time difference

between where they were and London -

every four minutes would translate
into one degree of longitude.

But in practice,

it was virtually impossible to keep
track of the time back in London.

The clocks of the period
were pendulum clocks,

and as soon the ship started
to pitch and roll in the waves,

you can see it would've been
very difficult to keep good time.

But ocean travel was booming
in the 18th century -

something had to be done
to make it safe.

Parliament appointed
a committee of scientists -

the Board of Longitude -
to solve the problem.

And in desperation
they appealed to the nation,

offering a reward of £20,000
for the best solution.

That cash prize,
worth several million today,

became the catalyst for one of
the most world-changing innovations

in the history of technology.

Now, a new Longitude Committee
has been formed,

to oversee a prize offered by Nesta,
the UK's innovation foundation.

But the prize can only be offered
for one of the six problems

on tonight's short list.
And that's where you come in.

In this programme,
we'll be revealing

the details of those six nominated
challenges for the first time

and then asking you to vote

to decide which of the challenges
is worth the £10 million.

Your decision will launch
a five-year search

for prize-winning solutions
that could change the world.

Let's look at the first problem
on our list.

Bacterial resistance to antibiotics
has been a growing problem

for decades, and now poses
a very real threat to our health.

It presents a nightmare vision
of the future,

in which the health of practically
everybody alive on the planet

is at risk in a way that it hasn't
been for almost a century.

Since Alexander Fleming discovered
penicillin over 80 years ago,

it's been estimated
that antibiotics have saved

more than 80 million lives.

But now, there are some bacteria
that we're defenceless against.

Every year in the UK,
5,000 people die

because antibiotics can't kill
the bacteria they're infected with.

Looking at the problem
of antibiotic-resistant super-bugs,

here's Liz Bonnin.

Antibiotics have only been
widely available for 70 years or so

but the effect they've had
on our lives is nothing short
of extraordinary.

In that time, life expectancy
has increased by 20 years,

thanks in large part to
the dramatic reduction in deaths

from all sorts of infections
and infectious diseases.

Without antibiotics, modern medicine
as we know it wouldn't exist.

Routine operations would be
life-threatening

and everything from hip replacements
to chemotherapy and organ transplants

would simply be impossible.

But it seems the heyday is over.

Infectious bacteria
are becoming increasingly resistant

to the antibiotics we rely on
for protection.

We urgently need to preserve this
cornerstone of modern medicine

and to do that we need to understand
why resistance is on the increase.

I've come to Birmingham to meet
Professor Laura Piddock -

a specialist
in antibiotic resistance.

So, Laura, how can bacteria become
resistant to the antibiotics

that have been so effective
against them for so long?

OK, so it's best demonstrated
if we look at this plate here.

So you can see the bacteria
growing on the top of the agar,

and there's a disc in the middle
that's got antibiotic in it,

and the antibiotic is coming out
into the agar

and there's this clear zone
that's killing all those bacteria.

OK, so that's how antibiotics work?
Yeah.

But if you look very closely,
you can see there's little dots,

little colonies,
that have grown up overnight

so they are antibiotic resistant.

And the way that's happened is
they have a mutation in one gene

that now allows them
to resist that antibiotic.

And if we take one of those
resistant colonies,

and then do them on this plate
here...

One dot of that,
grown out on this agar?

Yeah. And you can see that
it's grown right up to the disc

with the antibiotic,
there's no zone of inhibition.

And that's it, a completely resistant
strain of bacteria to that drug.

And that drug becomes obsolete,
that's the end of its working life.

Yes. So what have we done
to contribute to this resistance?

Well, we're awash with antibiotics.

We need to stop using them
as much as we do,

not just in human medicine, we need
to stop using them in animals,

as much as they are, we need to stop
using them in the home.

We want to make sure patients get
the drugs when they need them,

but what we don't want to do is
have people using them

when they're just absolutely
unnecessary.

It's clear we need to halt
our excessive use of antibiotics.

50 million courses of antibiotics
are prescribed in UK hospitals

and GP surgeries every year.

And the trouble is,
up to half of those prescribed

are probably unnecessary.

If we could develop
a quick and easy way to tell

the difference between viral
and bacterial infections

then the use of antibiotics
could be dramatically reduced.

You can see we're on
a busy ward here.

We have sick patients
coming in all the time.

And it's often quite difficult
to work out clinically

whether they have a serious
infection or not.

That's the real challenge.

We often give antibiotics just
in case there's serious infection.

What we really need is
good strategies to be able

to deliver antibiotics to
the patients who really need them

with confidence
they have a bacterial infection

and not some other condition
or a viral infection.

So how do you go about discerning
between a viral infection

and a bacterial one?

It can be very difficult

but we are helped
with various blood tests

and there's a relatively new
blood test, a biomarker

called procalcitonin, and we can
use that in conjunction with

our clinical assessment
of the patient

to try and help us establish if the
patient has a bacterial infection.

Doctor Dryden is trialling a new
technique to measure procalcitonin -

a molecule found in the blood
which rises in concentration

when you have a bacterial infection
but not if you have a viral one.

I'm not on the ward for long
before a test is necessary.

We've just seen a very sick lady.

It's difficult to make a clear
diagnosis in this patient.

She could well have pneumonia
and septicaemia

but equally it may not be due
to a bacterial infection.

By using a biomarker like
procalcitonin that can help us

make a decision whether this patient
needs antibiotics or not.

After just 90 minutes,
Doctor Dryden gets the results.

We have just done the test
on the patient we saw

and the procalcitonin level
is below the cut-off.

So I presume you are not going
to administer antibiotics.

We held off the antibiotics
on the ward round this morning

and we'll continue to hold off.

We will continue to monitor her
and keep a close eye on her

and if her condition changes,
we may change that decision.

But at the moment,
she doesn't need antibiotics.

Because of this test, the hospital
has been able to have

the antibiotics it prescribes
when diagnoses are unclear.

But the equipment remains bulky
and expensive.

And as most antibiotics
are prescribed by GPs,

the test is nowhere near
fast enough.

Speed is absolutely of the essence
in the community.

If you think about how short
a consultation is with the GP,

a GP sees a patient for 10 minutes,
that has to be done
within that 10 minutes.

So, it's an exciting
time for the research

for the technology of these types
of tests, but how urgent is this?

I think it's really important
to develop this as soon as possible.

We know antibiotics in the past
have saved more lives

than any other drugs.

If we don't preserve
our antibiotics, or find new ones,

the future of medicine
is really in doubt.

Our massive overuse of antibiotics
across the globe is crippling

one of the most effective weapons
we have against infection.

We urgently need a solution

because this will affect
all our lives in the future.

If this subject is picked
for the Longitude Prize,

potential winners will need
to develop

a cheap, rapid test
for bacterial infections

that can be used easily by doctors
and nurses all over the world.

Getting a rapid diagnostic so that
we know we are treating bacteria

and ideally the right bacteria, will
save lives every day of the week.

We believe
the technology is out there

if only the little different
bits of technology

were put together in a black box
to make it work.

Our next nominated challenge
will demand revolutionary advances

in medical engineering
but has the potential

to transform the lives
of those affected in many ways.

Over the last few decades,
our ability to help people with

all sorts of physical disabilities
has moved on in leaps and bounds.

But our ability to help people who
are paralysed doesn't go much beyond

offering a wheelchair - just as
we would have done decades ago.

And there are 50,000 people
in the UK who are paralysed.

The loss of mobility
and independence that results

can be an enormous challenge
both physically and emotionally.

But for many people,
technology can play a crucial role.

Investigating paralysis,

here's Dr Saleyha Ahsan.

I'm a doctor
and I used to be an army officer.

In 1997, serving in Bosnia,
I saw someone

who had just lost their leg
after stepping on a land mine.

Watching him come to terms
with the reality of his future

as an amputee was something
that I've never forgotten.

He had this haunted,
lost look on his face.

And he knew at that moment
that his life was going to be

changed for ever.

Of course, injuries like that
are not confined to the battlefield.

Every eight hours, someone in the UK
becomes paralysed.

I'm meeting someone
who knows only too well

how easily our lives can be changed
in an instant.

Everything that I use
is in the lower cupboards.

I can just reach some of these

but not that easily.

You won't reach that wasabi.

No, don't like wasabi. The stuff
I don't like is at the top!

'Sophie has been in a wheelchair
since a road accident in 2003.'

I fractured my skull, my cheekbone,

apparently my eye
fell out of its socket.

My jaw was broken.

My collarbone was snapped
and my spine was damaged.

Basically, on impact
I was paralysed.

At the moment, the possibility
of repairing spinal injuries,

whether through surgery or stem cell
therapy, is a long way off.

Could engineering
and robotics help instead?

Sophie is helping to trial
a remarkable new device

designed by Richard Little.

It offers her the chance
to stand and walk independently.

This was extremely surreal for me
when I first got it.

To be able to select
the option of stand.

LOW MECHANICAL WHIRRING

Gosh. Do you feel quite steady?

Yeah, I do, which is amazing.

Just seeing your face now,
you've really lit up.

Can I see you walk?

Of course you can see me walk!

It may be slow and bulky

but the exoskeleton can transform
perspectives.

Oh, my God. The view.

Had you not seen the view?
No, not seen the view. Seriously.

Oh, wow! There's my car!

I can open the window!
I've not been able to do that.

For Sophie, a practical,

simple exoskeleton would also
help her physically.

You can live a healthy life
in a wheelchair. I mean...

But the time... The toll it takes
on your body is bad.

Small things. I've noticed
a slight scoliosis in my spine

and just from sitting because I am
sitting every day all the time.

That'll be straightening out
your core and everything. Exactly.

Richard, tell me about the amazing
technology that's gone into this.

It looks a simple device
on the outside

but it has 29 microcomputers
on-board all talking to each other,

managing the different systems
so there's a lot goes on behind it.

Sophie's increased mobility, the
physical changes she's experienced -

not to mention her joy -
is humbling to see.

But if paralysis is chosen
to be the Longitude Prize,

technologists will need
to develop exoskeletons

that are smaller, lighter and faster.

The hope is also that people
who can't use a joystick

to control one
could just use their thoughts.

Doctor Tom Carlson is honing
mind-control technology by trying

to move a robot
using his brainwaves.

So, Tom, you're going to be
controlling that little robot

with your mind. That's right, yes.

We've chosen 16 key electrode
positions over the motor cortex.

This is the part of the brain
that deals with me

trying to move my limbs.

To mimic the scenario of someone
who is completely paralysed,

Tom will control the robot,
not by moving his arms

but by thinking about moving them.

So, let's start this.

Oh, my God. He's walking.

As I keep this bar in the middle,
the robot goes forwards,

if I imagine moving my left hand,
the bar goes to the left

and the robot turns left. And that
is all coming from your brain.

You're thinking about it. Yes.

That's amazing.

Whilst you're talking to me,

are you still thinking about
moving left and right? Of course.

If I don't, the robot
will be running away.
I thought men couldn't multitask!

'It takes a lot of concentration
to control the robot.'

And you have cleverly stopped him
from walking into the cupboard.

No, he's going
to go into the cupboard!

Another problem lies in isolating
Tom's directional intentions

from the surrounding interference.

So, these signals are
very, very small.

The scale we're looking at here is
just an order of a few microvolts.

If I clench my teeth...

Oh, my word. Yes.

They completely saturate, so
when we are processing the signals

we have to filter out
all of this noise

so we can understand what's really
going on and ignore the rest.

There's no harm in a robot
bumping into a cupboard,

but developing this technology
to the point that paralysed people

can safely control exoskeletons
using their minds is a long way off.

To get this out into the real world,
onto the streets,

I think you're looking at decades.

As a doctor, I'm fully aware
that when I have a patient

who's paralysed, there's really
little I can do for them

apart from offer support.

But imagine if ultimately,
through robotics,

and better understanding of the
brain, we could find a way to bypass

a broken spinal cord,
and help a person to walk again.

If paralysis is chosen
as the Longitude Prize,

the challenge will be to invent
a system that gets closest to giving

paralysed people the same freedom
of movement that most of us enjoy.

We're asking the world

to solve the problem of paralysis.

And the great thing is
we don't tell you how to do it.

It could be engineering.
It could be neuroscience.

It could be biology.

You might find a new way
to grow new nerves.

We don't know.

The next problem on our list
of nominations is malnutrition,

a subject that regularly
hits the headlines.

But the tragic events that prompt
such media attention

are just the tip of the iceberg.

Beyond disaster-related famine,

climate and soil type
can leave people

with permanently restricted diets.

And of course
social issues like poverty,

education and illness play a part.

As a result, over 800 million people
around the world are undernourished,

with children the worst affected.

The vast majority are
in developing countries,

where one in seven
of the population suffers.

But it can affect us all.

In fact, just here in the UK,

over three million people
are either malnourished

or at risk of malnourishment,

with the cost of
ensuing health problems

running into billions of pounds
every year.

Malnutrition is a problem
that affects the whole planet.

Dr Michael Mosley asks how close
science is to finding a solution.

When you hear the word
malnourishment,

you probably think of natural
disasters, droughts, emergency aid.

But, in fact, malnourishment
is much wider than that.

They may not be starving to death,
but worldwide there are millions

of people who lack vital nutrients
in their diet.

120 million don't have
enough vitamin A

and many of those will go blind.

An astonishing billion,

maybe two billion people around
the globe are iron deficient,

which means they feel tired
and listless a lot of the time.

If you don't get enough vitamin C
in your diet, you get scurvy.

If you don't have enough calcium or
vitamin D, then you develop rickets.

One of the biggest problems
is a lack of protein

which can cause
a condition called kwashiorkor.

Now, much of our protein
comes from meat,

but livestock farming
can't feed everyone.

One option for
a more sustainable solution

is being explored
here in the Netherlands.

Scientists have teamed up with
the chef to cook me the sort of meal

a celebrity stuck in the jungle
might eat.

Good morning. Good Morning.

I like quiche, but I've never
had a mealworm quiche.

I keep on thinking they're
about to wriggle, come to life.

There's something of
a novelty value to my meal.

Thank you. Great.

I'm going to, sort of, tuck in.
Bon appetit.

Just when I cut into it,
suddenly you see them, falling out.

Ah!

It's delicious.

Entomologist Marcel Dicke
is serious about eating insects.

What, sort of,
is the nutritional balance?

What have you got here in the way of
fat and protein, things like that?

50% protein,
but, especially important,

the minerals are very high -
zinc, iron, magnesium.

In terms of composition, it's
similar or even better than beef.

So I could get more iron
from eating insects

than I could from eating beef?
Yes, definitely.

'Insects aren't just nutritious.'

They do provide a satisfying crunch.

'They're more efficient
to farm than livestock,

'which makes them more sustainable.'

For producing 1kg of beef,
we need 25kg of feed.

For producing 1kg of
similar quality insect meat,

you need only 2.2kg of feed.

Right, so that's 10%. Only 10%.

'Marcel's team helped compile a UN
report showing that farmed insects

'produced fewer greenhouse gases
and less ammonia than cattle.'

'They need less water and land, too.

'And 20,000 insect farms in Thailand
show it can be done cheaply.

'The numbers all add up,

'but there is still one thing
getting in the way.'

Well, the major barrier
in the Western world is here,

psychological, people need to get
used to it and I understand that.

If food technologists could find
a way round our squeamishness,

insects might become
more than a curiosity in the West.

But they aren't our only hope.

When it comes to easing
global malnutrition,

there is one area of research where
the potential is almost limitless,

and where they have recently
also made huge advances.

Unfortunately, it is also
incredibly contentious.

It is the genetic modification
of crops.

In the US, more than 80% of corn,
soya bean and cotton

produced in 2013
was genetically modified.

Here in the UK, you'd be pushed
to find any GM food in the shops.

But there's lots
of research going on,

because, as well as
increasing yield,

GM can make food more nutritious.

This is Rothamsted Research.

Now, it is the longest running
agricultural research station

in the world,

and the aim of this place is to get
the most out of the crops we grow.

This remarkable Camelina plant
contains omega-3 fish oil,

a vital nutrient thought to protect
against heart disease and cancer

and to assist brain function.

Now, it isn't found
naturally in plants.

But it is found
in oily fish like salmon.

That's the root of a major problem,

which Johnathan Napier
is trying to solve.

The global fish stocks
that we have at the moment

are sufficient
to provide our population,

our seven billion mouths, with about
a teaspoon full of fish oil a week,

whereas we probably need
at least double that, maybe more.

The situation's so bad
that a recent US survey attributed

over 80,000 deaths a year
to fish oil deficiencies.

So we're interested in
trying to develop

an alternative, sustainable
source of fish oils.

And these are our GM Camelina
plants that we've engineered

to accumulate omega-3 fish oils.

Now that is pretty weird.

So this, presumably,
this is the oil you produce, is it?

Yeah, so... How much is this?

I think in terms of the amount
of time and effort to produce it,

it's tens if not hundreds of
thousands of pounds. Per litre?

Oh, yeah. You'll have to get
the price down before you sell it.

Can I have a sniff?
I promise not to swallow.

You can have a sniff of it, as long
as you don't... Not to taste, yeah.

Hold it to your lips and drain it.
I would...

It's not at all fishy.

I mean, it's, sort of,
if anything, slightly cabbagy.

Camelina is a brassica species

and so it would have
a slightly cabbagy smell.

It is very strange, realising
that I hold in my hands there

something that could have quite
a significant impact on the future.

There are years of field trials
and legal debate ahead

for crops like this.

But it does show what
could be achieved.

I have seen two very
different approaches

to the problem of malnutrition -

genetically-modified crops
and insects.

Now, both could contribute
significantly in the future

or perhaps solutions will come from

some completely unrelated
area of research.

By 2050, there'll be nine billion
people on the planet.

To feed them, we need to
double food production.

Vote for food to be
the subject of the Longitude Prize

and the challenge will be
to create a historic innovation.

Something that offers everyone
enough to eat that's nutritious,

sustainable and delicious.

It could be immensely exciting.

You know, we're talking about
innovations that could

change the world, and if you look at
the history of innovations in food,

you think about
things like irrigation,

things like refrigeration,

things like fertilisers,
industrial fertilisers.

These have quite literally
changed the world

and changed the way
the human race has developed.

One thing that links each
of the nominated problems

is that a world-changing solution

needn't come
from renowned scientists.

Back in the 18th century,

as astronomers struggled to solve
the Longitude problem,

the Board appealed to
the British public for help.

And that was where a man named
John Harrison came in.

He wasn't from a university,
or a big engineering company -

he was a lone carpenter
and clock-maker from Yorkshire.

Harrison was convinced
the solution to the problem lay

not in astronomy,
but in inventing a clock

that would keep perfect time at sea.

I've come to the Horology Workshop
at Greenwich,

to find out how he solved
the problem -

with his revolutionary
Marine Chronometer, H4.

This is H4. This is H4.

Wonderful, it does look like
an oversized pocket watch.

Absolutely.

People are often confused,

thinking it would've been worn
in an enormous waistcoat pocket.

This wasn't Harrison's first attempt
to solve the problem.

For over 25 years,

he'd set his sights on designing
a clock that could handle

life at sea. After all, watches at
the time were hopelessly inaccurate.

It was to Harrison's great credit
that he was the one who

realised that was the wrong course
and that he needed to rethink

the technology completely, that's
when he started looking at watches.

He asked himself - why don't watches
keep time well? And he realised

there was a very specific reason and
that he could get round that reason.

Would you like me to open it up
and show you? Yes, please.

It's very exciting to see this.

It's beautiful.

If you think that's beautiful,
prepare to be astonished.

It's a wonderful thing.

Oh! Wow! Look at that.

Isn't that something?
Incredible! That's really beautiful.

It's OK to start it
if you'd like to hear it?

Yes, please.

I won't wind it very much.

That should do it...

To start it, you have
to give it a swift swing...

There it goes. Yeah.

Wow!

So what was so special
about the timekeeper,

what was Harrison's breakthrough?
His improvement was

the specification of the large
oscillating wheel, the balance.

In a clock, the oscillator is
the pendulum,

but in a watch, the oscillator is a
little wheel that swings to and fro.

You can see it flashing away through
the holes in the engraving. Yeah.

Harrison was the first to recognise
that with this balance

you needed to have large swings,

that is, not just swinging
through a few degrees,

but big circles of swings,
if you get me,

and also fast,
it has to swing very fast.

In H4 the balance swings
five times a second,

so that's really thrashing away
in there.

So moving it around on a ship

you're not going to disturb
that movement in the clock?

Yes, but received wisdom was
you must not do this.

Every trained professional watchmaker
had been told as an apprentice

never design a watch like this.

So Harrison was knowingly going
against perceived wisdom,

so it required someone prepared
to think completely outside the box

to enable him to succeed.

On its maiden voyage to the West
Indies, after nine weeks at sea,

Harrison's clock was accurate
to within just five seconds,

well inside the target of almost
two minutes for such a journey.

And though it was several more years
before he convinced the Board

that H4 wasn't a fluke,
he finally received

over £23,000 in prize money,
rewarding 43 years of work.

Thanks to John Harrison's clocks,

countless lives have been saved
at sea ever since.

It really was
a world-changing innovation.

It cemented Britain's position as
a global power, allowing sea trade

to flourish, and played a part

in fixing Greenwich at the centre
of world time once and for all.

This is the international meridian
or zero longitude line.

Now I'm in the Western hemisphere,

over here
I'm in the Eastern hemisphere.

300 years ago, a clockmaker from
Yorkshire changed the world.

Can the new Longitude Prize inspire
someone else to do the same?

In its report
published in April this year,

the Intergovernmental Panel
on Climate Change made it clear

that the world faces
an enormous challenge.

If we're to avoid dangerous
climate change in the 21st century,

we need to cut global
greenhouse gas emissions by 70%.

The effects of climate change
are already being felt.

And by raising sea levels,
changing our weather patterns,

and affecting our ability
to grow food,

climate change will
leave its mark on all of us.

And there'll be no single
solution to this problem -

it will demand multiple
technological innovations.

Most urgently we need to tackle
the world's top three

sources of emissions -
energy, industry and transport,

which alone accounts
for 13% of emissions.

Dr Helen Czerski is
investigating flight.

Ten years ago this would've been
a revolutionary vehicle.

Because this is an electric car.

Today, electric cars are entering
the mainstream.

Offering the potential
for road travel to be carbon-free.

But one form of transport
is miles behind

when it comes to
low carbon innovation.

And that is air travel.

If you're in one of those,
you know you're burning jet fuel.

And there are tonnes of carbons
belching from those engines.

If we're going to hit
current emissions targets,

just one return flight across
the Atlantic would use up

a passenger's entire
annual carbon budget.

To keep up with our appetite
for flight,

we need a low carbon alternative.

There aren't many yet.

But in Slovenia,

one family-owned company has been

experimenting with carbon-free
flight, on a small scale.

Launched in 2012,

The Taurus Electro won't be replacing
Jumbo jets any time soon,

but it's one of the most
eco-friendly planes in the world.

What is it that's
so special about this plane?

Well, there's no fuel involved
with this aeroplane at all.

it's an electric-powered aeroplane
that takes energy

from the battery and moves about
by using this little electric motor.

This is the battery.
It's really small!

It's really small!

It may seem small, but it carries

about tenfold of what
a car battery would -

and it's only three times the size.

In fact we're using the highest
energy density batteries

that are available on the market.

We're starting to see
lots of electric cars on the road,

why aren't there more
electric aircraft?

Because it's much more difficult -
the aeroplane has to lift the weight

of the battery pack, plus the
aeroplane and the people up aloft.

Well, let's see what it can do.

OK, electric aircraft, here we go.

It's so smooth.

The batteries contain enough power
to get the aircraft up to

an altitude of 2,500 metres.

At which point
we go into economy mode.

ENGINE DROPS OFF

Oh, God. Stop the engine.

SHE LAUGHS NERVOUSLY

I wasn't expecting that!

Actually, now we are a glider.
Right!

At the push of a button, the engine
shuts down, the propeller tucks away,

and the plane becomes a glider.

It really is carbon-free flight.

But with only an hour or so's
battery life in total,

you can't get very far without
thermals providing extra lift.

That's no use for a passenger plane
which needs to fly

anywhere in the world.

And bigger batteries would just add
weight and demand even more power.

The flight today was just
two people on a fun trip,

but what we want

is to transport hundreds of people
for hundreds of miles.

And the problem with scaling up
this technology is that

the best batteries we can foresee
just can't do that job.

Another approach to the problem
might be to abandon batteries

and explore completely new
power systems.

Like those being developed to drive
the next generation of spacecraft.

ENGINE ROARS

Here in Oxfordshire,

a team of engineers are developing
a revolutionary engine.

Its fuel has greater energy density
than batteries or fossil fuels.

It runs on liquid hydrogen.

How much better is hydrogen
than other available fuels?

It's about two-and-a-half times
the calorific value

per kilogram of a hydrocarbon.

Which means that gives you
the best fuel consumption

possible for the engine.

This isn't just about
getting into space,

you can use these ideas
for commercial flight as well.

Yes, and such a vehicle could fly
halfway round the world at Mach 5,

which would reduce the journey time

to Australia from something like 24
hours down to about four-and-a-half.

You'll just have time to drink
a few gin and tonics

and watch the movie,
then you'll land.

So it's got the power for a passenger
plane, but the real bonus is

that burning hydrogen leaves an
exhaust of almost pure water vapour.

So why isn't hydrogen used
to power our planes normally?

Because it's incredibly expensive
is the simple answer.

You've got to make
the hydrogen somehow,

and then you have to liquefy it.

And the liquefaction absorbs
a lot of energy,

and that makes it very expensive.

Sadly, it's not just the cost.

To make hydrogen fuel in the first
place relies mostly on fossil fuels.

And that means carbon emissions.

We need a cheap, clean hydrogen
source before this technology

can truly offer
carbon-free passenger flight.

It's just over 100 years since humans
first achieved powered flight,

and for all of that time it's been
powered by fossil fuels.

But now, there are hints
that it could be different.

There are new ideas - battery
technologies, hydrogen, biofuels -

and all we need is
a spark that will take us on

to a revolution in air travel
and give us carbon-free flight.

If you choose this problem as the
subject of the Longitude Prize,

the winner would need to build
a plane that can fly from London

to Edinburgh at a comparable
speed to today's planes -

with no carbon emissions.

The selection of flight was partly

motivated by the fact that it is
a challenge that can be

addressed by small
groups of creative individuals.

It doesn't require vast resources

to try and make
a different sort of aircraft.

The world's population is still
growing at an alarming rate.

In fact, there are nearly
twice as many people

alive on the planet today
as there were when I was born,

placing the planet's
precious natural resources

under ever-increasing pressure.

In its 2014 report,
the Intergovernmental Panel
on Climate Change

identified the supply
of fresh water

to the global population
as an area of major concern,

and the World Health Organisation
has predicted that by 2025

half of the world's population will
be living in water-stressed areas.

Professor Iain Stewart is
looking at the immense challenge

of supplying the world
with fresh water.

There's a reason
we call Earth the Blue Planet.

There's a lot of water on it.

Something like a billion
trillion litres in fact.

Of course, only a tiny proportion
of that is water clean enough

that you can drink
or put on your crops.

97% of it is sea water, full of salt.

And if you try and drink that,
the consequences can be fatal.

The obvious solution is to convert
this vast water resource

into something you can drink, by
separating the water from the salt.

But that isn't
quite as easy as it sounds.

So this is a solar still,
which is designed to take the heat

of the sun and convert dirty, salty
water into lovely drinking water.

It's basically an inflatable bag,
and I'm going to fill it with

a blend of water, salt and coffee
for an authentic muddy look.

I know it doesn't look nice.

But now we just let
the sun do its work.

Under the sun's heat,
pure water evaporates inside.

It condenses on the lid,
and eventually collects in the bag.

Of course, there's only
one real test of all of this.

Well, that's all right really. But
actually, there's not a lot of it.

We've had about five hours
of pretty constant sunshine.

And that's the problem really.

Generating fresh water
from saltwater using just

the energy of the sun
is a slow business.

It might be OK for occasional use,
but for a permanent supply,

we need a lot more energy.

Even here in London
engineers are turning to sea water

to boost dwindling water supplies.

This is one of the most advanced
desalination plants in the world.

This is where it all starts.
This is the Thames.

London is up there,
and the sea's down here,

so this water is really
pretty salty.

The water itself gets sucked up
by these huge pipes here,

up to 220 million litres every day.

Once all the muck has been filtered
out, the real job begins.

But instead of evaporation, this
place relies on pure brute force.

So, Simon, how do you get
the salt out of the water?

We've got to force
the water from the salty solution,

and we use these membranes
to do that.

So these rolls here...is kind
of what's in these tubes, is it?

Absolutely, we've got
about 10,000 of these on site.

And that's exactly what's
in each one of these tubes.

So how does this work then?

So you've got
the salty solution,

and it works its way
through the membrane,

and really, you get the clean water
coming out through the centre.

So this is where it ends up then,
is it?

Down that kind of tube there?
Absolutely.

The system is fighting against
a natural process called osmosis,

which normally drives water INTO
salty solutions, not out of them.

It's fighting that process
that takes all the effort.

So, if you think,
the normal pressure

in a car tyre is about,
what, two bar? Yeah.

This is about 84 bar -
40 times higher, the pressure,

to force the salty solution
against this.

It's the cost of actually providing
the pressure behind that,

that's the challenge.

At these pressures, the valuable
membranes quickly clog up with dirt,

making drinking water from here
around about 15 times

more expensive than regular water.

We desperately need
a cheaper, more efficient way

to convert large volumes.

No-one's found the answer yet.

But here in Gibraltar,
engineers are trying something new.

Peter? Yes? Hi.
You must be Iain.

'This new system separates
salt from water by

'taking advantage of osmosis,
rather than fighting it.

'And it can handle
18,000 litres a day.'

So what's actually going on inside?

If we could cut one of them open,
what would we see?

What you'd see inside of these
is some hollow fibres.

So this is a hollow fibre membrane.
These are tubes?

These are tubes.
Very, very fine. Oh, like hair.

Sea water flows
on the outside of these fibres,

and through the fibres we pump
what we call draw solution.

'That draw solution's the key,

'because it's more concentrated
than sea water.'

So, by the natural process
of osmosis,

we draw across, effectively,
almost pure water.

I guess the point is that
there's really no energy involved.

In this step there's very little,
it just happens naturally.

'It's a step forwards, although
for now, they still need to use

'pressure to separate
the water from the draw solution.

'Overall, it's more efficient,
but only just.'

OK, so let's have a...

Slightly nervous! Shouldn't be.

No, that's really nice.

'New systems like this are setting
the scene for a revolution

'in water treatment, but the real
goal is still a long way off.'

So the big question is,
is there an even better way

to take the almost limitless
supplies of that stuff

and turn it into water we can use?

'Fresh water is increasingly
precious yet essential.

'If this is the problem you choose
as the most important to tackle,

'then the prize will be awarded
to whoever can create a cheap

'and environmentally
sustainable technology

'to produce fresh water
anywhere in the world.'

You just have to read headlines,

whether it's in Beijing
or California and so on,

to know that the existing
fresh water infrastructure is

really under colossal strain
and we need some radical

new approaches to plumb the planet
in a fundamentally different way.

An undeniable benefit of
modern medicine is that all of us

can expect to live longer.

But an ageing population
brings challenges of its own,

in particular the task of caring
for those living with dementia,

including its most common form,
Alzheimer's disease.

According to the Alzheimer's Society
the number of people living with

the disease is set to double
in the next 25 years,

placing an immense burden
not just on the healthcare system

but on individuals, on their
families and care networks.

'As many as 50,000 people are
expected to leave work this year

'to cope with the demands of
caring for sufferers.

'Finally, Dr Kevin Fong
investigates how technology

'might also help with
this imminent crisis.'

Hello! Hello! Hello, how are you?
Fine, good, come in. Do come in.

'I've come to see Anne Delve.'

Anne. Hello, nice to see you.

'Five years ago, she was
diagnosed with dementia.'

Things aren't quite right sometimes

but you have to get that
in the right place in the head.

'Her sister Joy has moved in
to give her constant care,

'and their mother Joan also helps.'

For Anne, I think knowing that
she was ill was hard initially,

but also, when you've got to accept
that you've got to have help,

as with anyone with any kind of
illness, it's really hard.

Yeah, because, I used to...

used to go anywhere. Mm.

Erm, but, you know,
that's how things are.

It's the loss of independence,
isn't it?

'For people with dementia, even
simple chores can become difficult,

'as memory fades
and decision-making gets harder.

'But encouraging the keep-up
of everyday tasks

'can help slow the decline.

You've got the tap here
for the sink. Yeah.

D'you remember how to turn it on?
No.

If you want to turn the tap on,

you'd use the little switch here,
d'you remember? Just over there?

You can do that, and pull it
towards you. Just pull it.

I suppose I could. Give it a go.
I'm not going to burn myself.

No, that's cold water.

And then you can wash the cups up
for me, is that all right? Yes, yes.

You don't mind, do you? No.

Shall I wash this off now, then?
Yes, Anne. Leave this on here?

Do you want to put it on the
drainer? That's it, Anne, brilliant.

'While many people with dementia
have to move into care homes,

'sufferers are normally much better
off in a familiar environment.'

It seems important for you
that you're at home and not

somewhere else...
I think so, definitely.

..being looked after by strangers.
Yes, definitely.

That is great for Anne's health
and her wellbeing

because we're carrying on doing
what is normal in the home.

'But this sort of care can be
a huge burden on the family,

'so the hope is that
technology might offer help.

'At Birmingham University,

'researchers are one step closer
to the ultimate answer.

'A robot carer. He's called Bob.'

Bob can learn, in somebody's home,

where they typically leave their
newspaper or their slippers or

their keys, and use the information
so he can quickly find things.

Object located.

And you can see that
what he's done is

he's found the keyboard
and a bottle.

Bob can monitor
the positions of people,

so we're looking to detect,
has someone fallen over?

And also remind people or
notify carers that someone's

forgotten to take their medicine
or they haven't got up
at the time they should,

or they're getting up
at the time they shouldn't,

so they've gone out and walked
around in the middle of the night.

'With today's technology,
Bob's abilities are restricted.

'Stairs are a problem,
it doesn't have useful arms yet,

'and its decision-making is limited.

'For now, domestic robots are still
the stuff of science fiction.'

Of course, these things are
a very long way away.

Things are maturing
at different rates in robotics,

but one day we'll be able to
put these things together.

'Another approach
scientists are exploring

'is to make the home itself
part of the caring system.'

Pretty ordinary looking kitchen.
Tell me what's special about it.

OK, so, physically it's meant to be
unremarkable in that it's

meant to be like the sort of kitchen
you might have in an everyday home.

We've got sensors in the utensils,
sensors in the appliances

and sensors in the worktops
themselves to give you

a little bit of a nudge
at an appropriate time.

Well, let's have a look at making a
cup of tea in this automated kitchen.

So, kettle on.

The kettle itself has a sensor in
that measures how much water

is in there, so it knows that
you've got enough for a cup of tea.

The cups have a sensor in.

Open the tea caddy to get a teabag.

And as you've just seen there,
our environment's reasoned

that our kettle's boiled, our cup's
out, we're making a cup of tea.

And it knows that
we want to go for a teabag,

and I'm assuming
you can't instrument that as well.

Well, actually, we do in this case.

So we use sensors
in the teabag's tag here.

Pour hot water into the cup.

'With sensors attached to
everything I need to make a cuppa,

'the computer guides me
through every step...'

Pour some milk into the cup.

OK. There you go. It wants me to
get on with making your tea, yeah.

'..and monitors what
I'm doing all the way.'

And so it knows that
that's a stirring action,

it's seeing that through
the motion of the accelerometer.

Whereas if you put
the sensor down...

I'll just leave it there. ..it'll
know that you're not stirring.

That's pretty impressive.

'This system gives us a glimpse of
what technology could make possible.

'But the reality is
it doesn't yet have

'the artificial intelligence needed
to replace a human carer.'

Dementia is one of the most difficult

and devastating problems that we
face in science and society today.

We're a long way from any meaningful
treatment, much less a cure.

But in the meantime there's the hope
that technology might allow us

to live our lives as fully
as possible for as long as possible.

Come on. All right.

'Most of us will know
someone with some form of dementia

'during our lives,
and it's a growing problem.

'If this gets your vote,

'then the challenge to potential
winners will be to develop

'an affordable technology that's
truly capable of giving independence

'to people living with
the condition.'

It's a cruel disease, as you
watch the person you love change,

and you lose them,
but you still want to support them.

We can't throw the money at a human
caring system, so we need to think

about how we can use technology
and smart devices to enable them

to live on their own with dignity
for longer.

Carbon free flight,
paralysis or food?

Dementia care,
fresh water or antibiotics?

'Six vital problems facing us today,

'but only one can benefit from the
£10 million Longitude Prize Fund.'

We want to get the whole country
involved in deciding

which of these challenges
the £10 million prize fund should be

offered for,
and in just a few moments,

when this programme finishes,

you can cast your vote
by text or online.

'and lots more information
on the challenges too.

'Voting will close at 7.10pm on
the 25th of June with the result

'announced live on
The One Show that night.'

It may take several years

but eventually someone somewhere
will come up with

an effective solution
to the challenge you choose,

and a genuine claim
to the new Longitude Prize.

300 years ago, that someone was
a clockmaker from Yorkshire.

This time, could it be you?