Poo used to create electricity
Imagine if your house was powered by poo... Well, that could actually happen in the future because of a clever idea being used at a sewage works.
At Beckton sewage treatment plant, they turn our waste into 'poo cakes', which they then use to power the building.
They do it by taking all the poo and wee and putting it into a machine that squashes it into dry poo cakes.
The cakes are then burnt in a furnace to produce steam, which then powers a turbine to create electricity.
It might sound cool, but Hayley thought it was pretty disgusting at the sewage plant.
She said: "It stinks - the whole plant smells a bit like a mixture of red peppers, cauliflower and sick - nice!
"And on top of that I actually held a pice of the poo cake. Now I like cake, but this is one piece of cake I would not like to eat with my tea!"
A machine at the plant
Sewage plant manager Harjeet Singh said the process was "totally green".
Before poo cakes, the plant pumped all its poo waste into the North Sea. Incredibly, a boat loaded up with sewage left every two minutes.
Now, all that's left is four lorry-loads of ash a day, which is created when the waste is burnt. Mr Singh said they were looking into ways of getting rid of the ash in an environmentally-friendly way.
Beckton sewage plant takes in poo and wee from homes in London, Berkshire, Oxfordshire, Hertfordshire and Surrey.