Bigger may not always be better but when it comes to solar power generation it's a plus. The rooftop photovoltaic power installation at the Milan trade fair will cover around 270,000 square meters (2.9 million square feet) and have a peak installed capacity of at least 18 megawatts. This will put it ahead of the biggest existing rooftop solar plant at General Motors in Zaragoza in Spain, which has a peak capacity of 12MW.

Five contractors will be given the opportunity to bid to build the plant at an estimated cost of ∈70–80 million (USD$99–113 million). The installation is expected to be completed by mid-2010.

Ferrucio Ferranti, CEO of Sviluppo Sistema Fiera, a unit of the Milan fair group, said: “The winning bid will be the one that offers us the highest rental."

The winning developer will pay the Milan trade fair rent and in return will be able to sell the power generated. After 20 years the plant will become the property of the trade fair.

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