LISBON, Dec 19 (Reuters) - Portugal's Galp Energia expects to start 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 primarily an oil producer and refiner, stated on Thursday.

In 2015 Galp entered into 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 capacity of 270,000 metric heaps each year.

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

Galp stated in a statement it received on Wednesday the 3 reactors to biofuels, which will enable the HVO unit to "produce SAF and biodiesel in 2026 ... placing Galp at the leading edge of establishing low-carbon services vital for the energy shift".

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