This page is fully or partially automatically translated.
Make an appointment with
So that you can make an appointment, the calendar will open in a new tab on the personal profile of your contact person.
Create an onsite appointment with
So that you can make an onsite appointment, the appointment request will open in a new tab.
Halving of the mains power supply
Photovoltaic systems are a sensible investment for breweries, as the electricity yield over the year is parallel to the beer output. This practical example shows how the efficiency of such a system could be optimised by storing energy in surplus periods and how it could be realised economically with the budget of a small medium-sized brewery.
The new refrigeration centre in the brewery's former ice cellar Initial situation
The storage cellar cooling of the 1st Dampfbierbrauerei Zwiesel had previously been implemented by a Linde NH3 direct evaporation refrigeration system with evaporation condenser. The condition of the system, the lack of automation and the insufficient cooling capacity led to increased energy consumption and problems with temperature control, especially in summer, as well as to a hygienically unsatisfactory situation, as owner and senior manager Dr Dieter Pfeffer explains.
Preparation and implementation
In 2017, an energy consultation conducted in advance by the company "FS industrielle Energieberatung" had revealed a savings potential of approx. 35.2 MWh/a. The on-site analysis by the company Trane Roggenkamp also assessed the savings potential as correspondingly high. The decision for a new automatic refrigeration system was therefore imperative for brewery boss Dr Pfeffer from a technological, technical, safety-related and financial point of view.
The installation of the new brewery cooling system began in April 2018 in the brewery's previously unused ice cellar. This meant that the old cooling system could continue to run, so that only a short period without cooling had to be bridged during the changeover. Since the beginning, the new system has been running fully automatically and without failure. The automation and adjustment of the system's control can be viewed and parameterised from anywhere and at any time via the web browser-based visualisation.
The renewal of the refrigeration system resulted in the following improvements:
- Full automation of the cooling operation;
- drying of the storage cellars;
- no icing of the coolers;
- fast and precise cooling of the fermentation vats and relief of the (actually) too small ice water basin;
- reduced electricity demand of the cooling system by over 30 MWh/a, despite lower and more constant cellar temperatures.
The condensers of the new refrigeration plant The new plant
In order to meet the brewery's budget, a cost-optimised series refrigeration machine was used, which is operated with four capacity stages and two independent refrigeration circuits with scroll compressors.
Generously dimensioned, dry condensers (not subject to the federal ordinance on evaporative cooling systems, cooling towers and wet separators) dissipate the waste heat quietly and efficiently to the environment. High-pressure malfunctions are virtually excluded due to condensation temperatures of up to a theoretical 67 °C.
Keeping an eye on overall efficiency
Evaluation
The brewery's beer output has been constant since 2017 and was also maintained in 2020 due to an increased proportion of bottled beer. In contrast, the electricity demand for the cooling supply has fallen by almost 36 per cent since 2017, as forecast, although the new system has permanently called up a significantly higher cooling capacity. In 2022, Dr Pfeffer also plans to connect the wort cooling system to the new refrigeration system using a glycol ice storage tank, which he expects will further reduce energy costs.
Despite the aforementioned savings, the total energy consumption from the grid was high. This resulted in high electricity costs and a poor carbon footprint. In addition, power peaks led to very high provision costs from the energy provider.
Generating own electricity
"We agreed that we could only counteract this problem by using self-generated and self-consumed solar power through a photovoltaic system," Dr Pfeffer reports.
After this decision was made, the new photovoltaic system with 84 kWp was put into operation in June 2020. The brewery's own electricity generation and use of the photovoltaic system (PV system) alone reduced the brewery's grid consumption by a further 60 MWh/a. In addition, the brewery was able to feed about 15 - 20 MWh/a into the grid.
Beer battery: Maximising the use of your own electricity
With the existing Trane Roggenkamp equipment, a PV surplus control was implemented in 2021 or the existing control logic was expanded. During the day, the surpluses from the PV system can be stored directly in the storage cellars - the beer battery - in the form of cold via the power-controlled refrigeration machine. The storage cellars are thus slightly supercooled (down to - 2 °C air temperature). In the example of the steam beer brewery, 340 kWh can be thermally stored at full storage volume (3000 hl) if the beer itself is cooled 1 °C lower.
The refrigeration machine transports the PV surpluses to the storage cellars up to its capacity limit. If the solar radiation increases, the output of the refrigeration system also increases dynamically and thus the power consumption. The shading of the PV system, which took place around midday, was perfectly compensated for by the system.
Due to the surplus control, the room air temperatures drop - depending on the solar radiation - to as low as - 1.5 °C in the room for about 5 - 6 hours and rise again to the set temperature during the night. In most cases, no further cooling is necessary at night.
The photovoltaic system installed on the brewery's roofs in 2020 Halving of the mains power supply
Taking into account the energy savings of 32.8 MWh/a, the use of own electricity by the PV system of about 60 MW/a and the extended use of own electricity by means of the surplus control of 15 MW/a, the electricity consumption from the grid has been reduced from 211 583 kWh/a to 103 783 kWh/a, i.e. by about half.
Economic efficiency analysis
Conclusion
In addition to the lower power consumption, the significantly improved consistency of the cooling is at least as important an advantage of the new system. This is reflected in the refinement and continuity of the brewery's product quality.
The increasing appeal of local beers among the population also brings new challenges for every brewery. Future-oriented and environmentally focused technology plays an essential role here and has an extremely positive effect on the brewery's image these days.
Tobias Schlögl from Trane Roggenkamp is convinced that glycol-based, indirect cooling systems with low refrigerant quantities are the future. He advises paying attention to auxiliary energy needs and questioning stalled processes.
