TOKYO, May 31 (Reuters) - Japan's biggest power generator JERA is in talks with companies at home and abroad including resource majors, shipping companies and local electric utilities to build a global supply chain for ammonia as a fuel, its president said on Monday.

Ammonia is used for fertiliser and industrial materials, but is also seen as an effective future energy source, along with hydrogen. It does not emit carbon dioxide when burned, though its production creates emissions if it is made with fossil fuel.

JERA, a joint venture between Tokyo Electric Power and Chubu Electric Power, aims to achieve net zero emissions of carbon dioxide by 2050 and 20% use of ammonia at its coal-fired power plants by 2035.

It has already signed a memorandum of understanding (MOU) with Norwegian ammonia maker Yara for the delivery of emissions-free ammonia as fuel for electricity generation in Japan, following an agreement with Malaysia's Petronas to discuss collaborations in ammonia and other energy areas.

"We are also in discussions with various companies, including resource majors, state-owned companies, shipping companies, domestic electric utilities and plant manufacturers," JERA President Satoshi Onoda told a news conference, without giving names of the companies.

"We will strive to build a green ammonia supply chain by continuing to promote alliances worldwide from both supply and demand sides," he said.

JERA plans to begin a demonstration project to develop technology to co-fire ammonia and coal at a 1 gigawatt (GW) commercial coal-fired power plant.

In an effort to expand its renewable power assets to 5 gigawatts (GW) by 2025 from 1.2 GW as of March, JERA said it and its partners Equinor and Electric Power Development Co (J-Power) submitted a bid this month for three offshore wind power projects in Akita, northern Japan.

Separately, JERA has begun an environment assessment process for two other offshore projects, one off Ishikari Bay in Hokkaido and another in Tsugaru in Aomori, northern Japan, it said. (Reporting by Yuka Obayashi Editing by Mark Potter)