OLYMPIC SPECIAL..ALL ABOUT THE CAULDRON

Olympic cauldron built in 'Bond-style gadget workshop' says architect as organisers vow to make giant flame carbon neutral

• Thomas Heatherwick surprised unique design given go-ahead by 2012 chiefs
• Fuelled by natural gas which is pumped through each of its 204 petals stems
• Petals made from steel using acid treatment that gives it 'bad black' colour
• Organisers working with EDF energy to ensure all emissions will be offset
• Rehearsals carried out at night to keep details a closely guarded secret
• Entire structure weighs just 16 tonnes. Cauldron in Beijing was 300 tonnes

By Daily Mail Reporter

The lighting of the Olympic cauldron at last night's opening ceremony was, if nothing else, wonderfully unique.

The giant flame's design was so sophisticated the studio where it was crafted looked more like James Bond's gadget workshop, its architect revealed today.

Thomas Heatherwick said he was pleasantly surprised when the idea to have 204 separate petals come together to form one giant flame got the go-ahead from a range of officials including Prime minister David Cameron and London 2012 chairman Lord Coe.

Going green: Each of the 204 petals is fuelled by natural gas, which means energy consumption can be reduced significantly and the flame will still burn brightly

Measuring just 8.5 metres high and weighing 16 tonnes, it is far smaller and lighter than ones from previous events. The one lit in Beijing four years ago weighed a staggering 300 tonnes.

Mr Heatherwick, who developed it at his Heatherwick Studio in Kings Cross, London, said: 'We were aware cauldrons had been getting bigger, higher, fatter as each Olympics happened and we felt we shouldn't try to be even bigger than the last ones.

'This incredible event has 204 nations coming together, so we had a child from each country bringing these copper polished objects in.

'At the end of the Games, this cauldron will dismantle itself and radiate back down to the ground and each of those copper pieces take away by each nation and put in a national Olympic cabinet somewhere.'

Blooming marvellous: This series of photographs shows each of the 204 copper and steel petals of the Olympic cauldron being lit before being lifted up to form one giant flame

The London Organising Committee of the Olympic Games (Locog) requested the flame be powered by natural gas, which is pumped individually through the stems of each petal.

A spokeswoman told MailOnline: 'The multiple burners means that the burn-rate is flexible.

'The gas flow can be reduced very significantly - this means we can reduce our gas consumption from 100 per cent down to 15 per cent.

'We are constantly monitoring the flow rate to ensure the minimum quantity of gas is burned.'

Locog is also working with energy company EDF to see that all of the carbon emissions will be offset.

Intricate engineering has gone into the design to ensure the flame does not go out, in any 'unforeseen circumstances' it will relit by the 'mother flame' kindled in Olympia, Greece.

 The copper petals, created to be 'very small and humble objects', were made using traditionally skilled craftsmen of the sort who used to roll sheet metal to make body parts for car makers such as Bentley, according to Mr Heatherwick.

He said: 'It is like the biggest gadget that anyone can make in a shed but this shed is the most sophisticate shed in Harrogate.

'It was like the Bond gadget workshop.'

More than a billion people who watched globally along with the 70,000-plus crowd inside the stadium saw the unique petals being carried by each of the children as they accompanied each Olympic team into the stadium for the athletes' parade.

The rods which make up the stem of the cauldron are made of stainless steel with a heat and acid treatment that makes it a colour called bad black, which is actually slightly blue.

The petals are copper and the entire structure is about 8.5 metres tall and will be moved from the centre of the stadium overnight tomorrow.

It will move to the end of the stadium where the huge bell was struck to signal the start of the opening ceremony.

Like the cauldron the London 1948 organisers used when the Olympics were last staged in the capital, the cauldron will stay alight inside the stadium rather than being pitched above it.

The cauldron design team used the fact that the athletes' parade is a long event, lasting at least 90 minutes, to retrieve the elements from the centre of the parade and discreetly fix them to specific spots on the cauldron.

Practice had to be done at night as the lighting of the cauldron had to be kept secret.
Rehearsals were held in the north of England, but were switched to the stadium nearer to the grand event.

Mr Heatherwick said: 'It had to stay a secret. We had to wait until the dancers had gone home so it was about 3am - that was the time that it (the stadium) was available for use to use.'

The seven teenage up-and-coming athletes who made up the final torchbearers had 45 seconds to light the cauldron. There was then a 45-second wait before it all lifted into place.

By the time the first ring was in place the last one was lifting and coming together. 'So it was like a dandelion seed being blown - but it seemed to work, which was a huge relief,' Mr Heatherwick said.

Mr Heatherwick said he and artistic director Danny Boyle, the mastermind behind the opening ceremony, wanted something that was not about being bigger than the last Olympic cauldron, in Beijing, but was about the people involved in bringing it together.

This is one of the reasons why is was set in the centre of the stadium with the parading athletes surrounding it.

He said: 'We were thinking about this incredible object with 204 nations coming together. It was a challenge but it did not feel enough to design a different shaped bowl.'

The cauldron will be split up at the end of the Games and each piece will be returned to a competing national Olympic committee (NOC).

Mr Heatherwick said: 'The cauldron will dismantle itself and come back to the ground. These pieces will be taken away by the NOC.

'They will be these heated elements, maybe they will get buffed, but everyone will have a piece.'

Heatherwick Studio was established in 1994 by Mr Heatherwick, an Honorary Fellow of the RIBA and a Senior Fellow at the Royal College of Art.

He is the recipient of honorary doctorates from four British universities – Sheffield Hallam, Brighton, Dundee and Manchester Metropolitan.

He has won the Prince Philip Designers Prize and, in 2006, was the youngest practitioner to be appointed a Royal Designer for Industry.

He has served on numerous judging and advisory panels and has given lectures, tutorials and talks at the Bartlett School of Architecture, London’s Victoria and Albert Museum and Yale University.

The opening ceremony, put together by Oscar-winning director Danny Boyle, had been cut to three hours to ensure athletes did not get stranded and left unable to get home.

It was only when organisers put the final rehearsals together that they realised it would run too late for public transport.

But some viewers were miffed that it still didn't finish until gone 12.30am.

Ben Wilson tweeted: 'A great opening ceremony for @Olympics last night. But I am very tired this morning as it was a late finish.'

Darren Huckerby ‏added: 'Not a bad opening Ceremony, late finish though!'

Olympics Minister Hugh Robertson previously denied the cut had been forced because of problems with the G4S security firm who failed to employ enough guards for the Games.