Alternative energy sources in milk processing
Companies with long-term plans have to reduce their dependence on fossil fuels due to the operational risk they represent. They are a finite, scarce resource controlled by a small minority and will be subject to increasingly strict restrictions in the foreseeable future as a result of their negative impact on the environment. At Emmi, we have been testing the suitability of alternative energy sources for industry use for almost 20 years.
Renewable energy sources are not new territory for us. In 2000, the Biedermann organic dairy in the eastern Swiss municipality of Bischofszell was the first Emmi site to switch to environmentally friendly wood chip-fired heating. Over the last decade, various alternative energy sources have proved successful in milk processing:
- Where: Bischofszell (Molkerei Biedermann), Emmen, Hatswil (Käserei Studer) (all in Switzerland)
- Interesting facts: The biggest challenge with using wood as an energy source is logistics. If large quantities of wood are required, these often have to be transported over long distances. Although burning wood does generate CO2, it is the same amount as the tree absorbs from the air when it grows, making wood carbon-neutral by definition.
- Where: Bever (Lateria Engiadinaisa), Bischofszell (Molkerei Biedermann), Hatswil (Käserei Studer), Saignelégier (all in Switzerland), Nüziders (Austria), Dechow (Gläserne Molkerei) (Germany), Sebastopol (Redwood Hill Farm & Creamery), Petaluma (Cowgirl Creamery), Platteville (Emmi Roth USA) (all in the USA)
- Interesting facts: Solar energy can be harnessed in two ways: either photovoltaic cells can be used to produce electricity, or solar collectors can be deployed to generate heat directly. Photovoltaics has become widespread in recent years. However, it has a low level of efficiency (around 20 %) and its value to businesses mainly depends on funding. In Switzerland, for example, the payback time for a photovoltaic system is currently around 15 years. Heat production using solar collectors, meanwhile, achieves efficiency levels of up to 50 %, but such systems cannot be operated economically in the industry at the present time. This is likely to change in the coming years.
- Where: Dagmersellen (Switzerland)
- Interesting facts: Product remains are always left over in machines and pipelines during milk processing, which then enter wastewater after cleaning. In countries where wastewater entails costs – such as Switzerland – pre-cleaning of the water may in some circumstances make sense. In doing so, the organic waste can be fermented into biogas, which in turn can be converted into a source of energy using a microgas turbine. Inhibiting factors are the high level of investment, the proximity to residential areas and the required technical know-how.
- Where: Landquart
- Interesting facts: The heat generated from the burning of general waste is usually fed into a district heating network. Connecting industrial plants to such networks is therefore of interest, since they have a year-round need for this heat. Critical factors in such projects, however, are the routing of pipes and the substantial costs of the pipelines.