During the end of 2024 researchers from Sintef Ocean AS visited their ENOUGH-project partner Rørosmeieriet (demonstrator 2). Rørosmeieriet is the largest ecological dairy in Norway. The aim, together with Rørosmeieret, is to monitor the energy consumption in their processes and to improve their heating and cooling systems. Traditionally, the heating and cooling demands are covered through separate systems: a refrigeration system to cover the cooling demand, and a fossil-fuel or electricity-based steam boiler to handle the heating loads.
At Rørosmeieret, multiple CO₂ heat pumps have been installed to cover the cooling demand and partly the heating demand. The CO₂ heat pumps are installed to efficiently produce hot water on the hot side, while covering the cooling demand on the cold side. This system supplies the dairy to meet their thermal energy demand while also improving energy efficiency and reducing costs compared to traditional systems.
The rest of the heating demand requires higher temperatures, which is covered by an electric steam boiler. This electric boiler creates steam used for pasteurizing milk, yoghurt, and cream. Since this is a process that requires a lot of energy, and pasteurization requires about half of the heating demand, Sintef Ocean wants to investigate how installing a high-temperature heat pump will affect the energy reduction.
To do this, the researchers require more knowledge about the thermal demand of the system, which is gathered from installed energy meters. These instruments measure the energy consumption of the thermal management system and the heating and cooling consumption. This data is gathered to give an accurate representation of the system, which will act as a great tool to analyze the system performance and to develop further system improvements.
An issue, however, is that their heating and cooling demand typically don’t occur at the same time. This is something that they’ve considered and have therefore installed thermal energy storage systems for both heating and cooling to counteract this issue. Today, the dairy has installed multiple tanks for both types of demand, but based on data, it is seen that a larger thermal energy storage is required. This is one of the reasons why Sintef Ocean together with Rørosmeieret through the ENOUGH project want to consider cold thermal energy storage using phase-change materials to meet this demand using a compact solution. This technology will not only help the system meet their desired temperature, but it will also benefit the electrical grid by reducing their power peaks, as well as stabilizing the system by reducing the number of fluctuations that their system experiences throughout a production day.
Take a look at the Norwegian Dairy demonstrator to see how innovative energy solutions are improving efficiency and sustainability :
Authors: Lucas Köster and Jan Bengsch SINTEF Ocean