Penrith could become the home of a $500 million redevelopment which would include the construction of a new roofed stadium on the land currently occupied by Sportingbet Stadium and the adjoining harness racing track.

It is understood the ambitious proposal is being driven by Penrith city, Harness Racing NSW and politicians including local MP Stuart Ayres, who is also Fair Trading Minister.

Possible face lift: Sportingbet Stadium currently occupies the area where a proposed $500 million development would take shape. Credit:Getty Images

The finishing touches are being put on a master plan for the 35,000-seat stadium, which is expected to cost $300-$500 million. Its success hinges on the proposed Badgerys Creek airport.

The stadium could be used by NRL teams, the Western Sydney Wanderers, the Penrith Emus rugby union club and other local sporting teams, and could host concerts and events.