JAKARTA, July 24 (Reuters) - Indonesia, the world's most significant palm oil manufacturer, is evaluating fuel with a view to increasing to 40% from 35% the share of palm-oil blended into biodiesel next year, the energy ministry stated.

If executed, the B40 mandate could increase biodiesel usage to up to 16 million kilolitres (KL) next year, the ministry said, from 13 million KL estimated to be consumed in 2024.

"We hope the trials could be finished in December, so that full execution of B40 could be brought out in 2025," energy ministry senior official Eniya Listiani Dewi said in a declaration on Tuesday.

The Indonesian Biofuel Producers Association (APROBI) said the market had the capacity to satisfy B40 demand, with installed capability expected to increase to 20 million KL yearly next year from 18 million KL now.

"However we will require more basic materials to meet B40 need," Ernest Gunawan, the secretary general of APROBI told Reuters on Wednesday.

The biodiesel market would need 13.9 million metric lots of unrefined palm oil to produce 16 million KL biodiesel next year, from the 11 million loads needed this year, he included.

Indonesia's biggest palm oil association GAPKI said a decrease in exports implied there would suffice raw materials to provide the B40 required for now.

But the industry would need to assess "which one would be better", GAPKI chairman Eddy Martono stated, referring to the possibility an increase in exports would make providing the domestic market less viable.

Indonesia's palm oil output is estimated to reach 54.4 million heaps in 2024, a 2.26% boost from in 2015, while exports are anticipated to decrease by 2.47% to 29.5 million tons as domestic usage rose, driven by biodiesel mandate.

The ministry had actually tested the biodiesel, blended with 40% of palm oil, on a train for the very first time earlier today, while preparing to test the B40 mix on agriculture machinery, power plants and in the shipping market, it stated. (Reporting by Bernadette Christina and Dewi Kurniawati; Writing by Stanley Widianto; Editing by John Mair, Savio D'Souza and Barbara Lewis)