FORMER MANCHESTER United chairman Sir Roy Gardner has taken a stake in Mainstream Renewable Power, the latest venture fronted by Airtricity founder, Eddie O'Connor.

When Mr O'Connor launched the business earlier this year, Sir Roy, who has also chaired British utility Centrica, was named as a non-executive director.

Returns recently lodged with the Companies Registration Office show that he has taken 166,666 shares in Mainstream, out of a total of 45.5 million, giving him around one-third of 1 per cent in the company.

Sir Roy, who lives in Hertfordshire in southern England, is a well-known figure in British business.

In one of his more high-profile roles, he chaired Manchester United plc during the period when the US-based Glazer family launched its successful bid to buy the club and take it private.

Mainstream Renewable Energy's returns show that Mr O'Connor is the biggest shareholder, with 30 million units, or just under 66 per cent.

Last month, Mainstream announced that the investment arm of British bank Barclays paid €20 million for a 15 per cent stake in the company, valuing it at a total of €133 million.

This puts a price tag of €86 million on Mr O'Connor's holding. When the company launched, he revealed that he had invested €30 million of the estimated €50 million he made from the sale of Airtricity to Scottish Southern Energy.

The returns show that Mainstream executives Torben Andersen and Fintan Whelan hold 200,000 and 1.6 million shares in the company respectively. Director Fintan Drury holds 333,333 units.

Mainstream plans to invest in alternative energy projects in Ireland, Europe and around the world.