© Fleischwaren Berger GesmbH & CO KG, ca. 1.00 m² Flachkollektoren bei Fleischwaren Berger (AT)

Flat-Plate Collectors at Fleischwaren Berger GmbH & CO KG

Fleischwaren Berger is an Austrian family business with a history going back to the year 1890 when Michael Berger opened his first butcher’s shop. Today the business is managed in fourth generation by Rudolf Berger with its domicile still being in Sieghartskirchen. Currently Fleischwaren Berger has 500 employees and a sales volume of 125 million € (2012).

80…100 tons of meat are delivered to the company Berger daily and are mainly produced to ham and sausage-products. The company uses ca. 10 GWh electricity each year for the production, 50 % of that for the cooling system, and additionally 14 GWh fuel oil for the company’s thermal energy demand. Thus, the company spends around 2 million € for energy per year.

In order to save energy costs and contribute to preserving fossil fuel resources, the company decided to build a solar process heat plant. The plant was designed and installed by SOLID and taken into operation in the end of July 2013. The initial plan to install the system on top of the production hall has been discarded due to the rooftop’s insufficient load capacity. Instead, the collector field with 1,067 m2 of area was installed on an open field next to the production site as depicted on the photo above.

Improved large-scale flat-plate collectors with an area of 12 m2 each were used for the collector field. Besides a thicker insulation on the backside, the collectors are equipped with a second cover made of a heat resistant foil beneath the glass cover. The collector field has a maximum performance of around 0.6 MWth.

The heat produced by the collector field is stored in a 60 m3 buffer tank which is designed for a pressure of 4 bar and heated up to a temperature of up to 110 °C. Out of the tank the heat is used for two different processes: preheating of the boiler feed-water and the production of warm-water, which is predominantly used for cleaning processes. The picture on the right-hand side shows a hydraulic of the solar process heat plant at Fleischwaren Berger.

© Flachkollektor Fleischwaren Berger
The 1.067 m² collector field heats up the 60 m3 buffer tank, which supplies heat for the processes of heating up boiler feed-water, warm-water production, and air-drying in the ventilation plant.

The company has a feed-water demand of ca. 2.7 m3/h which is mainly caused by the direct use of steam for ham and sausage cooking. The required fresh-water is pre-heated to ca. 30 °C after the water treatment by heat recovery from the cooling system and subsequently heated up to ca. 95 °C by the solar thermal plant. The remaining heat demand is supplied by the steam boiler.

The company’s high warm-water demand of 7 m³/h results mainly from the high cleaning demand to ensure hygienic production conditions. Additionally, the warm-water circuit is used for drying the ventilation system in order to avoid too much humidity. For that purpose, the fresh-water, preheated to 30 °C, is heated up by solar heat to up to 70 °C.

The system provider SOLID guarantees Fleischwaren Berger a yearly solar yield of 500 MWh (~470 kWh/m2bruttoa). Considering the plant’s overall costs of 738,500 € including the integration costs and a duration of use of at least 20 years that makes for a solar heat price of ca. 75 €/MWh (without funding). However, since funding from the Austrian large-scale plant incentive programme and an additional regional funding could have been used, the funding rate was at 65 %, reducing the solar heat generation costs for Fleischwaren Berger to 27 €/MWh. Due to the high thermal energy demand, the solar coverage rate is at roughly 5 %.

Thanks to the solar process heat plant, the company Fleischwaren Berger saves ca. 62,500 l of fuel oil a year and preserves the environment by greenhouse gas emissions of 163 tons.