Example of Agrana Fruit Germany GmbH

Two gas-fired steam boilers are operated by AGRANA Fruit Germany GmbH at their site in Constance, which generate steam for the process heat and for sterilising the fruits. Depending on the base material and temperature, about 20-30 standard cubic meters (Nm3) of biogas is generated per hour with a heating value of about 6-7 kWh/Nm3 in an anaerobic reactor. By installing a new gas burner in one of the two steam boilers, a large part of the accrued biogas is now used instead of natural gas for generating steam. Before the modernisation, the gas was burned using an excess gas burner. The annual consumption of fuel was reduced by 290,000 kWh and the costs by about € 10,000. By installing a multi-fuel burner system, a speed controller and a O2 and CO-driven flue gas control for the new gas burners, additional savings of about 160,000 kWh could be achieved. The implementation of all these measures resulted in an annual reduction of fuel consumption by 448,000 kWh and reduction in cost by € 19,300. The CO2 emissions were reduced by about 109 tons mainly due to the elimination of natural gas as fuel. The return on capital of this energy saving investment is 30 percent.

Reduction in energy consumption

448,000 kWh / year

Energy savings in percentage

4.2 %

CO2 reduction*

109 tons / year


€ 65,000

Cost reduction

€ 19,300 / year

Return on capital

30 %


* The following equivalent values as per Gemis are the basis for all the examples: Natural gas 244 g CO2 / KWh.

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