Automation refers to the utilization of software and hardware to carry out tasks that are typically performed by humans. In the context of brewing, which has historically been a manual batch process, automation has become increasingly prevalent in recent times. Even small-scale breweries, brewpubs, and dedicated homebrewers have adopted automated processes.
The primary advantage of automation is that it frees up brewery operators to attend to other tasks while the operations run “hands free.” Additionally, automation can lead to reduced labor requirements. Consistency is another benefit, as automation eliminates errors that are inherent to human involvement, such as forgetfulness, lack of oversight, or variations between different operators.
Simple automation can be as straightforward as using a computer chip with one input (e.g., from a temperature probe) and one output (e.g., a cooling valve). More complex automation involves a programmable logic controller (PLC) with multiple inputs and outputs, a personal computer (PC) with a human-machine interface (HMI), communication cables connecting the PLC to the PC, and various hardware components integrated throughout the brewing process. The operator selects and executes a program stored on the PC, which is then loaded onto the PLC. Once loaded onto the PLC, the program runs independently of the PC.
Each program consists of a series of steps, developed by computer programmers under the guidance of brewing authorities. Each step may also include specific parameters that must be met before proceeding to the next step. In an automated brewhouse, multiple programs run simultaneously and often in synchronization with one another. The purpose of the program is to replicate the actions previously performed manually by the brewer. For example, to open a valve, the PLC sends an output signal to a pneumatically actuated butterfly valve. If a proximity switch fails to detect successful valve opening within the specified time, a fault alarm is typically displayed on the HMI, prompting operator investigation.
To achieve automation, various sensors are necessary to replicate manual processes. These sensors include those for detecting empty pipes, monitoring pressure differentials and head pressures, converting pressure into vessel levels, and measuring temperature (each process requires different sensor types).
A proportional, integral, derivative (PID) controller plays a crucial role in automation. It is typically employed in processes requiring precise control rather than simple on/off or open/closed operations. As the PLC issues commands to hardware components, the PID controller continuously monitors the results and makes small adjustments if deviations from the target occur. This constant adjustment occurs as long as the controller is engaged.
PID controllers are commonly used in several brewhouse processes. Examples include controlling steam valves for hot water and wort boiling, managing lauter speed and differential pressure for lautering efficiency, and regulating the wort cooling valve to control the flow of ice water through a heat exchanger for wort cooling. Depending on the brewhouse’s budget and specific applications, PID controllers may find other uses such as yeast pitching and turbidity measurements.
For experienced brewers, transitioning to automated systems can be challenging but necessary. As small breweries expand and aim to produce multiple batches of beer wort per day, automation becomes essential for continued growth. Once the automated programs are optimized and all functions meet expectations, the desired operations can be consistently executed. Automated programs do not alter themselves, and brewers who are new to automation learn to trust and appreciate its benefits. Well-designed systems provide high flexibility and enable brewers to make necessary changes and easily program new recipes.