This weekend the new Wembley Stadium will host its first full capacity event as Manchester United and Chelsea clash in the FA Cup Final. But to get there, there's an awful lot that's gone on first.

The technology needs of the new stadium are varied. Under the four acre moveable roof section and the 133 metre-high arch is one of the most technologically advanced stadia in the world.

For example, there will be 35 miles of heavy-duty power cables running through the stadium. These will cater not only for general needs but also for the huge amount of power needed to broadcast the stadium's events around the globe.

Two giant widescreens bookend the new stadium - each the size of 600 domestic television sets. Screens in football stadia have come a long way since a Sony Jumbotron was installed at White Hart Lane in 1995.

Microsoft is a founding partner of the new £798 million arena. It'll be involved for at least the next four years providing software and systems. For its £5 million, the software giant will also get its name above the entrance and 100 billboards around the ground. The company gets exclusive use of the stadium for one day a year until 2010 as well. Bit of a shame Vista 's UK launch was before the stadium was handed over to the FA in March then.

The FA's stadium operator, Wembley National Stadium Limited (WNSL), says that the stadium is expected to have over two million visitors per year.

"Wembley Stadium plays a unique role in British life - it's a national icon that has inspired generation after generation of young people with the dream of playing and performing at Wembley," says Microsoft's UK marketing officer Nick Barley.

The new stadium also has an 'official supplier' deal with npower . It'll be the first UK sporting venue to be powered using renewable energy.

And then there's the broadcast of the Cup Final itself. As well as the usual BBC1 and Sky Sports showings, both Sky Sports HD and BBC HD will be carrying the Cup Final in high definition. But the BBC will be providing the pictures as the host broadcaster.

"High definition is growing, but so far it's seized the nation's imagination a bit less than some pundits expected. The BBC's first full HD broadcast was the World Cup 2006, and there's a handful of HD channels available on the Sky platform and cable," muses the BBC's director of sport Roger Mosey.

"In the UK we're in a position where most people who have it love it - but it's some way from being a mainstream proposition."

Amazing scale

The scale of the structure is incredible. With a span of 315 metres, the arch will be the longest single span structure in the world. Whereas the old Twin Towers were 35 metres tall, the new roof is 52 metres above the pitch. It has a massively bigger footprint too - 103,000 square metres compared to 40,500m square metres.

The fixtures and fittings have also demanded much attention. London Bridge-based industrial design firm Curventa Designworks created touchscreen information terminals for the new stadium. They're designed to promote the 10-year Club Wembley seat packages and other information about the venue.

For visually impaired supporters, the new stadium will boast major technological advantages such as a radio system to transmit commentary to all parts of the ground.

One of the key challenges for the new stadium was actually nothing to do with technology at all: grass. Wembley is all about the pitch. And the major problem was keeping it as green as the national stadium's pitch should be. The pitches at many club grounds - notably Old Trafford and Stamford Bridge - have suffered as stands have been built ever higher. And increasingly large swathes of grass remain in near-permanent shadow.

This doesn't just make for a bad pitch. It also means that watching matches is difficult as TV cameras struggle to cope with the contrast of shade and bright sunshine during games.

The stands at the new Wembley stadium are higher and closer to the pitch than ever before. To top it off, the pitch is 4 metres lower than the old one. To meet the challenge, the new design was computer modelled to minimise the impact of shade on the pitch. The result? At 3pm on Cup Final day only the two southern corner flags will be in the shade - if the sun manages to shine, of course.

In the pink

The modelling mimicked the effect of sunlight on the stadium. Though it obviously didn't predict that some of the seats would go pink as they did last week . Air flow and movement were also looked at. The roof can be moved quickly in the event of inclement weather too. A speedy 15 minutes is the closing time of the four acre moveable section.

The total roof area is 11 acres - most of which hangs from the 133 metre-high arch. The 315 metre arch supports all the weight of the southern part of the roof and two-thirds of the other half. It has been designed to glow rather than shine. Light pollution has been greatly considered in the design process of the stadium, while crowd noise will be kept within the bowl. Concert sound has also been minimised - though until George Michael sings his first line on 9 June, we won't fully know the effect.

The most striking and highly visible feature of the new stadium will be the 133 metre tall arch that sits above the north stand. The steel arch is 315 metres long and will become the longest single roof structure in the world. It will be visible right across London.

Another benefit of the computer modelling is that seat views can be looked at. Many clubs now give ticket holders the ability to see the virtual view from their seat in the ground. And Wembley is no exception.

Computer modelling was also used to look at crowd behaviour. Crowd Dynamics is a company run by University of Warwick Mathematics researcher Keith Still. Still has developed some revolutionary mathematical tools using a part of Chaos Theory called Orchid Fractal Analysis. He uses this to provide extremely accurate models of how crowds behave. His company specialises in producing crowd simulation software and virtual reality models for crowd analysis.

On the track

More technology was used to plan out how the stadium could host a world-class athletics event as well as football. Football stadia with athletics tracks are generally accepted to be less atmospheric than those where fans are closer to the pitch.

Architects HOK Sport and Foster and Partners got round this by designing a removable prefabricated platform that can be placed over the lower part of the bowl - hence the low pitch. The platform will cover some of the seats but it creates the increased space needed for a 400m track. The platform would take "a few weeks to install and remove," according to Wembley sources.

However, one area where Wembley won't take advantage of technology is in its ticketing - which promises to remain rudimentary. The FA refused to replace 1,600 FA Cup Final tickets issued to Liverpool fans for last year's final at the Millennium Stadium after they were stolen from a Post Office van.

The FA claimed there was no way to distinguish between the originals and their replacements. And the problem is set to continue at the new Wembley despite the millions spent on the project. By contrast, all World Cup and European Championship tickets now include a scanable chip.

At the time a WNSL spokesman told The Guardian : "We are working on a number of solutions but ultimately we will not be able to guarantee that the same problem won't occur in the future."