- For years, Grolsch has been implementing energy-saving measures to reduce the energy consumption of beer brewing.
- One of Grolsch’s goals is to use as little natural gas as possible and to brew CO2 neutral beer in the long term.
- Grolsch has developed sustainability plans for the coming three years, which will include heat pumps.
According to Susan Ladrak, engineering manager at Grolsch, many energy-saving measures have been implemented in the new brewery. Nevertheless, the company managed to reduce energy production by another 30 per cent after commissioning, thanks to savings in the production processes that use cooling and heating.
During fermentation, Grolsch beer is cooled down to around 13 °C. During conditioning, the temperature must be lowered to -1 °C. Six compressors supply the cold. The cooling installation uses around 30 to 40 per cent of the total electricity requirement. Ladrak: “That’s a lot, and it’s why we keep looking for ways to improve.” For this purpose, the brewery has mapped out the cooling system for the first time: what about cooling demand, can the temperature be higher? “We have recently placed a new, more efficient engine on the compressor. We have also installed a variable-frequency drive. This has increased efficiency.”
The company has performed a data analysis to make a prediction model, in which the cooling demand is related to the number of compressors that must be switched on, in relation to the amount of energy consumption. “What is the most efficient circuit of compressors, for producing as energy-efficient as possible in a specific situation? That is the goal. We are even investigating the outside temperature and the energy consumption of the compressors. How can we adjust the settings of our compressors in such a way that we produce as efficiently as possible in both the summer and the winter?”, Ladrak says.
One of Grolsch’s goals is to use as little natural gas as possible. One of the options is to run the brewery on hot water instead of steam. Ladrak: “The temperature of that water must then be higher than 105 °C. The idea is to use hot water from the waste incinerator, and bring it to a higher temperature with a heat pump: from 105 to 135 °C. That is technically possible, but it requires a huge investment.”
Another option is using a heat pump to convert residual heat from the brewery into steam. That, too, is being investigated. This also applies to modifying other installations to run on electricity. “For some, this can be done at a limited cost – thousands of euros per installation – and a limited effort.” According to Ladrak, it becomes a lot more complex when modifying a gas boiler, as the demand for electricity then increases enormously. We must check whether the transformers are suitable, whether we have sufficient capacity and whether the electricity cables are thick enough.”
For the power capacity, Grolsch is explicitly looking outside the brewery. Together with Nouryon (the old Akzo) and Apollo Vredestein, the brewery is investigating the possibility of a regional heating network in Twente, connected to city heating. These are options for the longer term, Ladrak says. “It should not be the case that our processes run very inefficiently when we stop using natural gas.”
Grolsch has made sustainability plans for the coming three years. “Heat pumps are developing quickly. Something too expensive now might be affordable in a few years. We will see what the world looks like in three years and adjust our plans accordingly.”