News: ORG UPDATE 1-Origin Energy posts 46% plunge in first-quarter APLNG revenue on lower prices

(Adds APLNG output details, electricity sales and gas volume figures, comments on LNG prices)

Oct 30 (Reuters) - Australia's Origin Energy (ORG) said on Friday first-quarter revenue from its stake in the Australia Pacific LNG (APLNG) project fell 46%, hurt by lower realised prices for its oil and gas.

The Sydney-based power and gas retailer said spot LNG prices started to recover in September due to improving global gas demand and it expected prices to recover further in the second quarter.

Gas from Origin's share at the APLNG project was sold at an average price of $5.81 per metric million British thermal unit (mmBtu) in the quarter, 40% lower than $9.67 last year.

APLNG is a joint venture between Origin, ConocoPhillips COP.N and China's Sinopec 600028.SS , and it is the largest producer of natural gas in eastern Australia.

Origin Energy said sales in its energy markets business were largely in line with a year earlier, while gas volumes slipped 7%.

Origin's share of revenue from APLNG reached A$373.9 million ($266.6 million), compared with A$688.3 million a year ago. The figure also missed brokerage RBC's estimate of A$429 million.

Output at the project rose 3% to 64.2 petajoules (PJ), and came slightly ahead of an RBC estimate of 63.2 PJ.

($1 = 1.4027 Australian dollars)