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

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

It will change waste materials, such as utilized cooking oils, into renewable biodiesel and biojet fuel, also referred to as sustainable air travel fuel (SAF), utilizing green hydrogen produced by an electrolyser powered by wind or solar energy.

Galp said in a declaration it got on Wednesday the 3 reactors to biofuels, which will enable the HVO system to "produce SAF and biodiesel in 2026 ... positioning Galp at the forefront of establishing low-carbon solutions necessary for the energy transition".

Galp is likewise 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