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

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

"We hope the trials could be completed in December, so that complete application of B40 could be brought out in 2025," energy ministry senior official Eniya Listiani Dewi stated in a statement on Tuesday.

The Indonesian Biofuel Producers Association (APROBI) said the market had the capacity to satisfy B40 need, with installed capacity anticipated to rise to 20 million KL annually next year from 18 million KL now.

"However we will require more basic materials to satisfy B40 demand," Ernest Gunawan, the secretary general of APROBI informed Reuters on Wednesday.

The biodiesel industry would require 13.9 million metric lots of unrefined palm oil to produce 16 million KL biodiesel next year, from the estimated 11 million lots required this year, he included.

Indonesia's greatest palm oil association GAPKI stated a decline in exports indicated there would suffice raw materials to supply the B40 mandate in the meantime.

But the industry would require to evaluate "which one would be better", GAPKI chairman Eddy Martono said, describing the possibility a boost in exports would make supplying the domestic market less practical.

Indonesia's palm oil output is approximated to reach 54.4 million lots in 2024, a 2.26% boost from in 2015, while exports are expected to decrease by 2.47% to 29.5 million loads as domestic intake rose, driven by biodiesel mandate.

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