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 constructing at its Sines refinery in 2026, the business, which is mainly an oil manufacturer and refiner, said on Thursday.

In 2015 Galp participated in a 75%-25% joint endeavor with Japan's Mitsui to invest 400 million euros ($415 million) in the Hydrogenated Vegetable Oil (HVO) plant, which will have a production capability of 270,000 metric lots each year.

It will transform waste materials, such as utilized oils, into sustainable biodiesel and biojet fuel, also called sustainable aviation fuel (SAF), using green hydrogen produced by an electrolyser powered by wind or solar power.

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

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