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 blended into biodiesel next year, the energy ministry said.

If carried out, the B40 mandate might increase biodiesel usage to approximately 16 million kilolitres (KL) next year, the ministry stated, from 13 million KL estimated to be consumed in 2024.

"We hope the trials could be finished in December, so that complete implementation of B40 could be performed in 2025," energy ministry senior official Eniya Listiani Dewi stated in a declaration on Tuesday.

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

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

The biodiesel industry would require 13.9 million metric loads of crude palm oil to produce 16 million KL biodiesel next year, from the estimated 11 million heaps required this year, he added.

Indonesia's biggest palm oil association GAPKI said a decline in exports meant there would be enough raw products to supply the B40 mandate in the meantime.

But the market would require to assess "which one would be more important", GAPKI chairman Eddy Martono stated, referring to the possibility a boost in exports would make providing the domestic market less feasible.

Indonesia's palm oil output is to reach 54.4 million loads in 2024, a 2.26% increase from in 2015, while exports are expected to decline by 2.47% to 29.5 million loads as domestic consumption increased, driven by biodiesel required.

The ministry had actually tested the biodiesel, blended with 40% of palm oil, on a train for the very first time earlier this week, while planning to test 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)