UPDATE 1-SP AusNet to raise up to $318 mln; cuts distribution

* One for four rights issue priced at A$0.78

* Offer priced at about 13 pct discount

* Funds to pay down debt, fund capital expenditure (Adds details, background)

PERTH, May 12 (Reuters) - Australian infrastructure firm SP AusNet (SPN.AX) plans to raise up to A$415 million ($318 million) through a rights offer to help fund a growth programme, but forecast a 32 percent drop in its distribution for 2009/2010.

SP AusNet, 51 percent owned by state utility Singapore Power, joins a rush of Australian companies seizing on a recent rally in shares to tap equity markets to overcome difficult credit markets.

The one for four rights issue is offered at A$0.78 a share, a 13 percent discount to SP AusNet's last traded price of A$0.90. The shares dropped 21 percent last year amid the global financial crisis and have fallen about 5 percent this year.

SP AusNet said in a statement the institutional component of the offer has been fully underwritten and will raise A$330 million, while about A$85 million could be raised from retail investors.

Singapore Power intends to participate for its full 51 percent entitlement under the offer, representing approximately A$211 million, SP AusNet said.

The group, which has a five-year plan to spend A$2.7 billion on its energy infrastructure network, said the funds raised would be used to pay down immediate debt, while new debt will be redrawn to fund capital expenditure.

The group on Tuesday also reported an 5.4 percent increase in 2008/09 underlying net profit from a year earlier to A$177.2 million. Final distribution was 5.927 cents, bringing total distribution for the year ended March 31 to 11.854 cents.

Reported net profit fell 6.7 percent to A$146.9 million.

It forecast 2009/2010 distribution at 8 cents per security, down 32.5 percent from a year ago. Capital expenditure in the year would rise about 18 percent from last year's A$471.5 million. (Reporting by Fayen Wong)