At the family-run bakery "Löwenbäcker Schaper" from Braunschweig, quality and regionality are top priorities both in their bakery and in their energy supply. Since 2019 they have been using a Spanner Re² energy system to generate electricity and heat from shredded pallets that accumulate in their business. Their energy concept stands for both sustainability and optimum added value.
In 1900, the great-grandparents of the current owner Thomas Schaper laid the foundations for the family-run bakery business. For over 100 years, a particularly responsible approach to resources has been cultivated and the focus has been on quality and regionality. It was therefore only logical for the Schaper family to opt for a sustainable solution when it came to energy supply. With the EnergyBlock from Spanner Re², the company has been generating electricity and heat from wood waste using the principle of combined heat and power (CHP) since 2019.
Shredded pallets as fuel for biomass power plant
The pallets produced in the bakery serve as fuel. These are processed into shredded chips with a shredder. The resulting fine material is also used as an energy source in the form of pressed pellets. This means that no material remains unused and the residual material, which was previously disposed of at a cost, now represents a profitable energy source.
"The fact that the plant is operated with wood from pallets rounds off our added value in the enterprise optimally and shows that one can use also an alleged residual material profitably with innovative concepts", so Thomas Schaper, owner of Löwenbäcker Schaper. Before the shredder chips are fed into the EnergyBlock the wood is dried fully automatically in a moving floor dryer to a water content of around 10%. With this residual moisture, an optimal wood gas conversion takes place in the biomass power plant. The gas is then converted into electricity in the CHP unit.
Primarily using own electricity
"With the EnergyBlock from Spanner Re², we generate an average of around 45,000 kWh of electricity per month, covering the biggest amount of our electricity requirements. In addition to our own use, we also feed electricity into the public grid," reports Schaper. "The plant, which is classified under the German CHP-Act, is eligible for a subsidy for the electricity generated from renewable sources. This not only reduces the energy costs in operation due to our own use, but we also receive a state subsidy for the electricity," explains Schaper.
Profitable hot water preparation for bakery with wood gasifier from Re²
Wood gasification generates heat as well as electricity. On the one hand, this is used to heat the production rooms and the workplace, and on the other, the heat flows into the moving floor dryer, which pre-dries the shredded wood chips. The demand for hot water in the bakery is considerable. Before the EnergyBlock was commissioned, a biomass boiler was used to supply hot water, which required around 55 tons of wood every year. With the new Spanner Re² system, the existing biomass boiler is only switched on at peak load times in the winter months. The heat generated by wood gasifier is now used for the hot water supply.
Project information:
- Plant: EnergyBlock with "HKA 70"
- Performance: 68 kWel, 123 kWth
- Automatic wood chips dryer
- Start-up: 2019
- Fuel: Shredded paletts + fine material processed into pellets
- Shredder and metal separator