BOFFIN Simon Webb has been given a seal of royal approval for his super green machine.

Simon and his Macclesfield company Accelerated Compost have created a new generation of composting machines - and they have been road-tested by Prince Charles.

The firm was asked to demonstrate its latest model to staff at Sandringham in Norfolk.

Simon was surprised when the heir to the throne appeared himself - and tested the machine with the remains of a full English breakfast.

Simon explained how his invention works and peeked inside the royal composter Prince Charles already rents from the company.

He said: "There was lots of toast, tomatoes and beans, quite possibly the remains of a fry-up, but nothing anyone of us wouldn't have. There were no Champagne corks or anything like that."

Dad-of-one Simon, 36, said he chatted with Charles for 45 minutes about environmental issues and he would love to offer him a job.

He said: "He was so knowledgeable about composting and all the legislation surrounding it, if I could have employed him I would have done."

After the metting Charles told Simon he wanted four more of the machines to install at Buckingham Palace.

A Clarence House spokeswoman could not confirm or deny what Charles has for his breakfast as `it is not something we consider to be part of his public life' - but she did add that he takes a close interest in environmentally-friendly measures.

Former automotive engineering student Simon and his dad John, 79, came up with the idea for the composter in 1998.

It uses natural bacteria and woodchip to break down waste and was patented in 2003.

The firm's current range of machines can transform between 600 and 7,000 litres of waste a week into compost.

Salford University bought one in February 2007 and says it is considering getting more to deal with all campus food waste.

Simon said: "It was a very great privilege to install one of our composters at Sandringham and I was delighted."