GIANT fan parks could recoup more than half of the £15m expected to be spent by Derby to stage the football World Cup, if it is chosen as a host city.
And a potential 15% share from tournament ticket sales could be used to help fund a £26m extension to Pride Park Stadium to bring it up to World Cup standards.
Experts at the city council have been using financial data from the 2006 World Cup in Germany to work out the economic benefits to staging the global tournament in 2018 or 2022.
The estimated figures have been adapted to fit with what Derby has to offer. They suggest involvement in the World Cup could bring in as much as £100m in revenue and investment to Derby.
Around £9m of this would be generated from fan zones and live sites, where supporters would also be able to watch games on giant screens.
Each area, such as Darley Park and the Racecourse, would be likely to have live music, food courts, fun fairs, fan football tournaments and wireless internet access.
Richard Williams, city assistant director for regeneration, said it was clear the costs of hosting the prestigious tournament could be more than recouped.
He said: "Take the fan fest sites, which is only one aspect of the bid. We agree with the Football Association that two sites will cost £2.9m and this forms part of the £15m we expect to spend.
"But we have calculated a combination of admission charges into the sites, such as £2.50 from about 30,000 visitors a day, and sponsorship, advertising and franchising, will bring in income of £6m.
"The income from live sites could be about half that of the fan fest sites, hence the £9m.
"We've been incredibly cautious with the figures but they do add up and it makes you aware of the amazing economic benefits of hosting the World Cup."
Derby is one of 16 cities campaigning to be part of the FA's bid to bring the World Cup to England for the first time since 1966, with only 12 cities likely to be chosen.
If picked, more than 200,000 football fans are likely to pass through Derby during the tournament.
Derby would also have to spend £26m adding permanent and temporary extensions to Pride Park to increase its capacity from 33,000 to 45,000, as required by world football's governing body, FIFA. Discussions are still taking place on how the £17m for the permanent element and the £9m for the temporary section of the stadium would be found but the council said it might include a new leisure complex within the legacy extension as a way of recovering other costs.
A lease arrangement with Derby County on the additional 5,000 seats which would remain is another possibility.
A potential £2.25m from Derby County's 15% share in World Cup ticket sales could also contribute to the stadium costs.
City councillors voted on Wednesday to underwrite Derby's £15m bid and, on November 26, Derby will submit its finished bid to the FA. A decision on which cities will be included in the bid to FIFA will be made in December.