Norwegian Energy Coast

Just beyond those islands is the North Sea,

which means that between here and home,

there's an awful lot of oil and gas.

Our North Sea gas may be running out,

but the Norwegians still have big reserves.

So, like asking the neighbours for a cup of sugar, we've had to come here.

This massive gas plant could be keeping you warm this winter,

because it's going to be supplying up to a fifth of Britain's gas requirements.

A fifth of the UK's gas -

that's the equivalent of supplying the needs of Scotland, Wales and Northern Ireland.

The gas lies 74 miles out to sea, nearly two miles below the waves.

It's gathered by platforms sitting on the seabed, then drawn through pipes

all the way to the processing plant here in Nyhamna.

I'm meeting the plant director, Bernt Granas,

to find out what happens before the gas is piped to us in Britain.

First of all we have to get rid of liquids. And it's a process that starts in these huge pipes here.

So when the gas comes ashore, it's not just pure gas.

It's sand, it's gas, it's water and it's antifreeze.

And how long does this whole process take?

From the gas when it arrives here on the beach, until it's on its way to the UK, it's 10 minutes.

10 minutes? And what about Norway, how much gas is used here?

-Oh, we hardly use any gas at all.

-So where do you get your energy?

We have hydro-electric power and for almost anything here,

and of course even this plant is running on hydro-electric power.

So you've got a plant here that's just cleaning up gas for

-export to Britain, but itself is powered by hydro-electric.

-Yes.

The Norwegians are fortunate.

They can fulfil many of their energy needs with hydro-electricity,

so they've hardly touched their gas.

But in Britain, we've become addicted to the stuff,

so now we're forced to go to extraordinary lengths to get it.

The gas leaves the plant here and begins its mammoth journey

all the way to Easington in Yorkshire.

746 miles in length,

this is the longest sub-sea pipeline in the world.

-So this is it. I can hear it.

-This is the gas you're hearing, gas going to UK,

70 million standard cubic metres every day,

making up one fifth of the gas need.

And how on earth do you go about laying a pipeline of that length across a seabed?

Well, it's quite impressive technology in a sense that

it's actually in 12 metre lengths, welded together, one by one,

and you put it on the seabed as you go,

and in the duration of two summers, you can do it.

I can hear this gas rushing through here at the moment -

how many more years do we have?

-Well, you have at least 40 more years.

-And are you still looking for more fields?

Always.

40 years - that's not long.

The world is facing up to the fact that we need alternative ways to harness energy.

But perhaps we can find some solutions to our future energy needs

using something else that we have in common with Norway,

our very long coastlines.

Wherever a river meets the sea,

you get a mixture of saltwater and fresh water.

The Norwegians' novel plan is to generate electricity

using salt and fresh water via a process called osmosis.

A good way to observe osmosis in action is to see how an egg

can be pumped up in size when it is immersed in fresh water.

Here are two ordinary hens' eggs.

First of all, I've placed them both in vinegar

to dissolve the shells away. What is left

is a bag of eggy fluid in a membrane.

All the shell has gone. Now, this one I've left like that as a control,

so we can see how big it was to start with.

The other egg I put in this glass of pure fresh water for 24 hours,

and you can just see the difference in size.

Just look at that.

So the membrane outside the egg is a semi-permeable membrane -

it allows water in,

but it doesn't allow the other substances inside the egg out.

So this is a good demonstration of osmosis.

The pressure in this egg is now quite enormous.

Water went in through my egg membrane, making it swell up.

'Now, exactly the same thing would happen

'if the fluid inside my egg was saltwater.

'It would still swell up, because the fresh water is drawn inside

'to dilute the most concentrated salty water.

'The pressure increases inside the egg, and harnessing osmotic pressure

'is the novel idea behind the Norwegians' power plant.'

-Hello.

-Hi.

'I'm meeting Stein Erik Skilhagen.

'He's created a model to show osmotic power in action.'

We have three chambers with saltwater,

and we have four chambers with fresh water.

So we've got alternating chambers of fresh and saltwater, and each one is separated by a membrane.

Yes, the pressure will increase and then, when it gets high enough,

it has to evacuate somewhere, and that's where we have this system.

-That's going to come out through these pipes here is it, and then turn our turbine?

-Yeah.

Inside Stein Erik's clever contraption

are four chambers of fresh water and three chambers of saltwater,

each separated by a special artificial membrane

similar to the skin around an egg.

Between the chambers, osmosis takes place, water forces its way

through the membranes from the fresh water into the saltwater chambers,

and that creates a pressure eventually forcing the excess

water out through these pipes and hopefully turning our model turbine.

Starting to get some drips coming through.

Oh, look at that, off it goes, that's really impressive.

And the water that comes out here,

that is brackish water, mixture of sea water and fresh water.

So that's spinning around nicely now,

so if you were to attach a generator to this you could make electricity.

We think this is going to be a very good way to produce new renewable energy.

The pressure osmosis can produce is enormous.

An osmotic power plant could harness energy equivalent

to nearly a 400-foot waterfall.

By exploiting this completely natural process, far more electricity could

be generated than from a conventional water wheel driven by the same river.

'The model may work, but scaling it up into a renewable resource

'to rival wind power is a big challenge.

'Full-scale power stations are still a long way off,

'but for me this is really surprising and promising science.'

If the Norwegian prototype works, then just imagine what that could mean for the UK.

We could look forward to a time when we could produce

clean, renewable energy from the fresh water and saltwater

that's so abundant along our coastline.