The Role of Industrial Automation in Reducing Energy Consumption

Using less versus using better

There are two broad ways automation helps with energy. One is making running equipment more efficient, by tuning and matching output to demand. The other, which is the subject here, is simply using less: not running things that do not need to run, and limiting use when it is costly or constrained. The two overlap, but separating them is helpful because they call for different tools.

Idle shutdown

Equipment frequently runs with nothing to do. Conveyors move empty belts, compressors idle, pumps recirculate, and exhaust fans and heaters operate in unused areas. Automatic idle shutdown addresses this with simple logic:

• Timers that stop a machine after a set period without activity.
• Sensors that detect whether material, a product or a person is present.
• Production signals that tell auxiliary equipment to stop when the line stops.
• Schedules based on shifts, weekends and planned downtime.

Several points need attention when designing this. Restart time should be acceptable, since a machine that takes ten minutes to come back may be left running by operators anyway. Some equipment suffers from frequent starts, because motors heat up during starting and some machines need warm-up, so limits on the number of starts per hour should be respected. And certain equipment should never be shut down automatically, such as safety-related ventilation or cooling for hot processes. Manufacturer manuals and process engineers define what is allowed.

Load shedding and demand limiting

Utilities often charge not only for energy but also for peak demand. Plants may also face limits on their connection or temporary requests from the utility to reduce usage. Load shedding is the practice of switching off or reducing less important loads for a limited time when total demand approaches a threshold.

How it typically works:

1. A meter tracks the facility’s demand.
2. A controller predicts or detects when demand will pass a set limit.
3. Loads are ranked in advance, from least to most important.
4. The controller reduces the lowest-priority loads first, then restores them when demand falls.

Loads that can often be paused briefly with little harm include some water heaters, battery chargers, certain ventilation, and processes with thermal inertia such as refrigerated storage or some ovens. The ranking must come from people who understand the process, because a pause that is fine for one load can damage product or equipment in another. Where this saves money, it is primarily about reducing peak charges, which may not reduce total energy used; the effect depends on the tariff.

Monitoring that prompts action

Automation also reduces consumption indirectly by watching for abnormal use. Possible alarms include:

• consumption outside normal range for the current production level
• equipment running outside its scheduled hours
• a compressor loading more than usual, which may signal a leak
• a motor drawing more current than before, which might mean friction or a failing component

Data from IIoT sensors and meters can feed these checks, and maintenance teams can use the alerts to investigate before a minor fault becomes a costly one. Reports also support people in making routine decisions with better information. This data-driven approach overlaps with predictive maintenance, since changes in energy draw can be an early sign of wear.

Matching supply equipment to use

Central utilities such as compressed air, steam, chilled water and vacuum often have the most to gain. Automated sequencing can shut down surplus compressors or boilers when demand is low. Pressure or temperature setpoints can be lowered when conditions allow. Valves or branches serving unused areas can be closed automatically. Fixing compressor air leaks remains important because automation can only reduce so much when waste is constant.

Practical cautions

• Never compromise safety or quality. Energy-saving functions must not override protective devices, alarms, interlocks or regulatory requirements. Changes should be reviewed through formal change control.
• Avoid nuisance behavior. If automation shuts a machine down at awkward times, operators may bypass it, and savings vanish. Involve them in designing it.
• Document the logic. Plant staff need to understand why equipment stops and restarts, so they can troubleshoot.
• Test and verify. Measure consumption before and after to confirm that a new scheme works as intended.
• Mind cybersecurity. Remote or networked control raises security considerations that should be handled with the site’s IT and controls specialists.
• Expect varied results. Plants with plenty of idle running benefit most, whereas those already running tightly have less to gain.

Choosing where to start

Identify the loads that run when there is no production, find what stops them being switched off now, and automate the easiest cases first, usually lighting, ventilation and auxiliary equipment on fixed schedules. Add demand limiting if the electricity tariff has a significant peak charge. Then use monitoring to keep finding new opportunities. For details suited to a particular plant, consult a qualified controls or energy professional; this article is general information only.