The investment in the new RNG/ biomethane plant amounts to more than €4 million, a quarter of this sum will be spent on modernising the existing infrastructure and biogas plant. One of the reasons why Catalonia's second-largest dairy producer is able to allocate a budget of this magnitude is that the biomethane sales had already been contractually secured at an early stage. The green gas is to be marketed as climate-friendly fuel via an energy service provider.
"We view this AD plant as an environmental investment, as it allows us to cut our own greenhouse emissions almost to zero and generate additional income from biomethane," explains Juan Bautista Pons Torrades, Managing Director and owner of Torre Santamaría.
The cattle farm in the province of Lleida is a trailblazer in other areas. For example, Torre Santamaría was one of the first to introduce the well digestible A2 milk. Moreover, in 2019, the business was the first dairy cattle farm to be certified by the Lactalis Group in recognition of its animal welfare efforts. The dairy group Lactalis purchases some 22 million liters of milk a year from Torre Santamaría and sells it under various brands.
"To produce this amount of milk, we keep 2,300 dairy cows and 2,100 calves on an operating area of 14.2 hectares," says Torrades.
Every year, some 60,000 t of input substances accumulate for use in the biogas production. Cattle manure accounts for about 90 percent of the substrates. Bedding consisting of ground straw as well as silage leftovers are also fed into the digester. Currently, WELTEC is setting up two additional stainless-steel digesters for the digestion of all residues on the farm. Each of the digesters has a height of 6.30 m, a diameter of 26.87 m and a capacity of 3,573 m3.
"After processing the biogas generated in the digesters, Torre Santamaría feeds 300 standard m3/h of biomethane into the natural gas grid," reports Mark Kornweibel, the Spanish sales partner of WELTEC BIOPOWER.
According to Kornweibel, the existing 250-kW cogeneration power plant will continue to be operated despite the transition to RNG production. The farm is thus able to cover its own demand for power, heat and hot water.
After the new plant is finished in summer 2021, Torre Santamaría will continue to satisfy its demand for energy from its own raw material. Moreover, the plant operation enables the Catalans to shoulder their corporate social responsibility and maintain a healthy balance between environment, social concerns, economic factors as well as security of food and energy supply.
