(Adds further detail on offer and previous offer, and director...

(Adds further detail on offer and previous offer, and director recommendation from paragraph 2)

March 4 (Reuters) - Australian renewable energy generator Genex Power Ltd (GNX) said on Monday it had received a non-binding proposal from Japan's Electric Power Development 9513.T for the shares it does not already own at an offer price of A$0.275 each.

The cash offer values the Brisbane-based firm at about A$380.9 million ($249 million) and represents a 48.6% premium on its last close from Friday.

The Japanese firm, which owns a 7.7% stake in Genex, had previously made an offer to buy the company at a price of A$0.240 per share, Genex revealed.

An independent committee of the board of directors of Genex had determined the earlier offer undervalued the Australian firm.

The committee has unanimously determined the new offer is in the best interests of Genex shareholders, the company said. ($1 = 1.5323 Australian dollars)