Some 13 billion plastic bottles are thrown away in the UK alone each year and, as a bottle takes around 700 years to break down, they will be there for some time.

But plastic can be recycled, indeed it is already turned into a multitude of objects; polyester fibres which can be spun into fabrics, new containers and so on, although recycling, of course, uses yet more energy.

Now a machine invented in Japan and installed for a year-long pilot project in Canada is turning waste plastic into oil, which can be used for heating fuel or diesel.