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Dick’s also got a mechanical mountain to climb. He’s got a few short days to manufacture a high spinning windmill.

With its oil reserves dwindling, Dubai switches its sights to tourism, building the Burj al Arab, a 60-storey hotel in the...

See how South Africa's landscape changed in the build up to the 2010 World Cup.

Now it’s time for Dick and Jem to proudly reveal their new thoroughbred delivery vehicle to the expectant new owners.

The next morning, and the whole bike has to be stripped down to get to the heart of the problem.

It’s not nearly as much as Jem wanted so he’s ordered the best air motors he can find, but these motors are normally used...

Dick and Jem have come to this scrap heap to collect an old vehicle to recycle.

So they’re building a moped powered by fresh air. They’ll replace the petrol engine with an air motor and the gas tanks...

Fortunately they still have the oil they made earlier. So it’s time for the ultimate test: will that oil fire up the grain...

Is there anything else on the farm they can use to fuel the grain dryer?

Although the tank seems leak proof, Dick and Jem are taking no chances with their potentially explosive gas plant. They’ve...

Andy has tipped them off about a tank. They could fill this with cow slurry and use it as a digester to make biogas.

The Planet Mechanics are trying to save one of the world’s most beautiful cities – Venice.

They’re worried that the engine might not be strong enough but to get the boat onto the plane, Alberto will need to give it...

The solar-powered taxi takes forty minutes to travel from Certosa to the heart of Venice. Taking its time is fine for tourists...