Potato processor shares success with sustainability
German company Agrarfrost offers processed potato products, including french fries, specialty potatoes, potato chips and flakes. European processors have worked to align themselves with the environmental goals passed by their home countries, especially the United Nations’ Sustainable Development Goals passed on Sept. 25, 2015.
Agrarfrost’s efforts, explained Anne Schlewitt, include using 100 percent green electricity, implementing zero-energy potato storage and using heat recovery technology.
With regards to storage, Agrarfrost was looking for something that would keep potato stock cool when in storage without utilizing too much energy.
“To produce throughout the whole year, potatoes need to be stored from September to June,” said Schlewitt. “In order to maintain good quality of raw material, we need to ventilate and cool the potatoes during this timeframe.”
To do this they built a new potato storehouse with a capacity of 40,000 metric tons. In order to neutralize the energy balance in the storehouse, the company installed a 900-kilowatt peak (kWp) solar power plant on the roof. They also made improvements to the roof and wall insulation to reduce energy loss. Furthermore, they installed variable capacity fans, and indoor transportation belts to avoid energy loss through open doors.
The improvements were so great they actually now produce more energy than they use. The potato storage consumes 792,000 kWh per year, but the solar power plant produces 810,000 kWh per year. According to Schlewitt, by using electricity produced from renewable resources the company has been able to reduce CO2 emissions by 1790 tons per month.
The third measure that Agrarfrost found important for reducing energy use and CO2 production was heat recovery. Since 2011, the company has run five heat recovery projects with a total investment of over 10 million euros (nearly $12 million). In one of the projects, Agrarfrost combined two different production lines: the heat recovery for the french fry and potato chip production lines.
“We got remarkable effects for efficiency,” said Schlewitt. “The second interesting aspect about this project is that we are not only using the heat for the blancher or the dryer or indoor heating, but we can also generate cold from the heat. We use the heat to generate cold for cooling the product.”
Through the project, Agrarfrost was able to save 24 GWh per year of thermal energy.
– Melanie Epp, contributing writer