Weber Sepp went into operation with an HKA 30 in September 2012. Due to increasing energy requirements, the system was upgraded from 30 to 55 kWel in October 2017. In 2018, the biomass gasification plant was expanded by a second to a total of 110 kWel, and in 2021 by a third. The CHP units were replaced by a large CHP unit with around 210 kWel. Re²'s flexible technology allows operators to choose the optimum output size and generate the amount of energy that the customer needs. With a thermal output of around 260 kW, the three wood gasifiers and the CHP unit supply 10 households and the company's own theater stadium with heat via a local heating network almost 700 m long. In addition, the wood chips required to operate the plant are dried in-house.
Heat for contract drying, electricity for municipal utilities
Weber Sepp also operates a contract drying facility for chips, square bales (hay/straw), grain maize, soybeans, etc. This is an additional source of income that the Re² biomass power plants offers the operator. In addition, the electricity produced of around 200 kW is remunerated by the Rosenheim public utility company in direct marketing.
Wood chips management
Weber's wood chip production is highly efficient. The entire plant is housed in a three-storey hall.
There are two drying systems:
On the one hand, there is a bunker dryer with an area of 60 m² for drying hay, maize and woodchippings, which is open at the front and can be driven over. Usually, 50 to 100 cm of dried material is laid out and delivered or collected by the customer immediately after drying. When drying the square bales, the bales are usually laid in a single layer. If there is an increased demand, the bales can also be laid in two layers thanks to the powerful blower. On the other hand, a moving floor dryer is located in the basement near the three wood gasifiers. The drying capacity of around 25m³ per day is geared to the fuel consumption of the three efficient HKA70 systems from Re². The moving floor dryer dries and continuously conveys the wood chips into an intermediate bunker. At the same time, the wood chips are sieved out on the conveying path. The fine particles are used as bedding by surrounding farmers, while Weber uses the long particles as firewood in its own kitchen oven. From the intermediate bunker, the wood gasifiers use the dry and sieved wood chips as required.
The storage container for the moist wood chips is fed at ground level. It extends into the cellar (where the moving floor dryer is located) and has a capacity of approx. 75 m³. The bunker is filled about twice a week. The concreted forecourt in front of the hall serves as a delivery area and, if required, as temporary storage. The screening of fine and long parts takes place on the upper floor of the plant and the dried wood chips are transported vertically upwards by an ascending screw conveyor for approx. 9 meters. After screening, the wood chips fall automatically into the intermediate bunker. The push floor dryer constantly demands the required conveying volume itself and is regulated by the fill level in the intermediate bunker and the automatically detected wood chip moisture. The wood chips are only conveyed further when they have reached the desired degree of dryness.
Weber Sepp's biomass power plant
The three HKA 70 gasifiers from Spanner Re² GmbH supply the large CHP plant with sufficient wood gas at a utilization rate of over 95% per year. Sepp Weber developed the feed of the wood chips from the moving floor dryer to the plant himself. According to the operator, the service costs for the plant are around one hour per day for the three wood gasifiers and the CHP unit. Added to this is the cost of the process for producing the dried wood chips and their procurement. Even the waste heat from the plant room is used to dry the wood chips in the moving floor dryer. The hot air from the dryer is extracted from the plant room through a generously dimensioned sheet metal duct.
