What indicators help detect energy losses in an industrial plant?

Detecting energy losses requires more than reviewing the total bill: you need to know where, when, and under what conditions energy is consumed. A reliable baseline and indicators tailored to the process help distinguish inefficiency from an increase explained by higher production, shift changes, or environmental conditions.

Checklist for locating abnormal consumption

1. Define what you are going to measure

Define whether the analysis covers the entire plant or only specific areas, lines, or auxiliary services. Include the relevant energy sources—for example, electricity, gas, or steam—and specify the analysis period. Also check which equipment and processes are excluded: an unclear boundary can conceal consumption or make comparisons invalid.

2. Check data quality and establish a baseline

Gather bills, meter readings, and, where available, production, operations, and maintenance data. Verify that the periods match, that there are no missing or duplicate readings, and that the units are consistent. If the available data only show the plant’s total monthly consumption, they will be useful for an initial assessment, but may not be enough to locate the source of a deviation.

Use a period representative of normal activity as the energy baseline. Note important changes that could affect the comparison, such as modifications to equipment, schedules, or production volume. The baseline is not a consumption target: it is the reference point against which performance is assessed.

3. Break down consumption by source, process, and equipment

Break down consumption, to the extent permitted by the data, by energy source and by area, process, or equipment. The aim is to prevent aggregated data from concealing differences between zones. Initially prioritize uses that account for a significant share of consumption or whose operation is critical; the analysis may reveal that different equipment requires different indicators.

If there is not enough measurement, identify where an additional reading would add value. Submeters or monitoring systems can help separate consumption that currently appears combined, but their usefulness depends on the data being reviewed and linked to actual activity.

4. Relate energy to activity

Absolute consumption does not always show whether a process is performing better or worse. Depending on the operation, compare it with variables such as:

• Energy per unit produced or per tonne processed.
• Energy per operating hour, batch, or cycle.
• Consumption relative to production volume, where the relationship is relevant.
• Variables that affect demand, such as outdoor temperature, load, or operating time.

A specific consumption indicator can increase even when total consumption falls, for example, if production decreases. That is why it is helpful to review total consumption and the normalized indicator together, and document which variables have been used. There is no single indicator that is valid for every plant: it must usefully represent the process being assessed.

5. Track indicators over comparable periods

Compare shifts, days, or months with similar activity conditions. Review trends and deviations from the baseline, but do not automatically attribute every difference to a loss: it may be due to changes in the product, schedule, production load, or equipment operation.

Where possible, set a monitoring frequency that allows variations to be detected in time. A monthly analysis can show general trends; higher-resolution data can help investigate brief events or changes associated with schedules and operating cycles.

6. Look for signs of avoidable consumption

Pay particular attention to:

• Consumption outside operating hours or during shutdowns, compared with what the operation requires.
• Demand peaks or repeated increases at specific times.
• Persistent changes in the consumption of a piece of equipment or an area without an obvious operational explanation.
• Deviations between lines or equipment performing comparable tasks, taking their differences into account.
• Losses or inefficient operation indicated by operational and maintenance records.

These signs help guide an investigation; on their own, they do not confirm a fault or its cause. Check them with production and maintenance managers and against the state of the process before deciding on an intervention.

7. Rank measures by feasibility and value

For each opportunity identified, estimate the potential savings using the available data and record the required investment, the conditions for implementing the measure, and its possible effects on operations. Distinguish operational adjustments from measures requiring equipment changes or investment. Prioritization can consider, at a minimum, estimated savings, cost, technical feasibility, and impact on production, quality, and maintenance.

Do not present a preliminary estimate as guaranteed savings. After implementing a measure, compare performance with the baseline and take into account any activity changes during the period.

How it fits into ongoing energy management

The process of measuring, analyzing, acting, and checking results is also part of energy management systems, such as the ISO 50001 framework. The standard provides a structure for managing improvement systematically; it does not require a specific technology or a fixed percentage of savings.

Energy audit or management obligations depend on the applicable regulations, territory, consumption, and characteristics of each company. It is advisable to check the requirements in force in each case: a general guide to indicators does not, by itself, determine whether an organization is required to conduct an audit or implement a management system.