LISBON, Dec 19 (Reuters) - Portugal's Galp Energia anticipates to start producing biodiesel and from waste in an industrial-scale system it is developing at its Sines refinery in 2026, the company, which is mostly an oil manufacturer and refiner, stated on Thursday.

Last year Galp participated in a 75%-25% joint venture with Japan's Mitsui to invest 400 million euros ($415 million) in the Hydrogenated Grease (HVO) plant, which will have a production capacity of 270,000 metric loads each year.

It will transform waste products, such as utilized cooking oils, into renewable biodiesel and biojet fuel, likewise known as sustainable air travel fuel (SAF), using green hydrogen produced by an electrolyser powered by wind or solar energy.

Galp said in a statement it received on Wednesday the 3 reactors to process biofuels, which will permit the HVO unit to "produce SAF and biodiesel in 2026 ... positioning Galp at the forefront of developing low-carbon solutions vital for the energy transition".

Galp is also investing 250 million euros in a 100 megawatt (MW) electrolyser unit to produce green hydrogen to power the refinery in Sines. ($1 = 0.9637 euros) (Reporting by Sergio Goncalves