LISBON, Dec 19 (Reuters) - Portugal's Galp Energia anticipates to begin producing biodiesel and biojet fuel from waste in an industrial-scale unit it is constructing at its Sines refinery in 2026, the company, which is mostly an oil producer and refiner, said on Thursday.

Last year Galp participated in a 75%-25% joint endeavor with 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 change waste products, such as utilized cooking oils, into renewable biodiesel and biojet fuel, also known as sustainable aviation fuel (SAF), utilizing green hydrogen produced by an electrolyser powered by wind or solar energy.

Galp said in a declaration it received on Wednesday the three reactors to process biofuels, which will enable the HVO system to "produce SAF and biodiesel in 2026 ... placing Galp at the forefront of establishing low-carbon solutions vital for the energy shift".

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