The power of the laser source is not the same as the amount of electricity consumed by the machine. A 12-, 20-, or 30-kW fiber laser delivers a specific optical power for the beam, but it requires more electrical power to generate that power—and in addition to the laser itself, the cooler, drives, CNC control, exhaust system, and compressor also consume energy.
One of the parameters used to describe the efficiency of a power source is wall-plug efficiency, i.e., electro-optical efficiency. In measurements published by the manufacturer for randomly selected Raycus 12 and 20 kW laser sources—used in STIGAL laser cutters—this efficiency exceeded 37%. This is a good, competitive result for a high-power industrial fiber laser. However, this value applies only to the laser source itself, not to the entire fiber laser cutting machine and all associated equipment.
What does “wall-plug efficiency” (electrical-to-optical efficiency) mean?
Wall-plug efficiency (WPE) describes the ratio of the optical power generated by a light source to the electrical power it consumes. Simply put:
Wall-plug efficiency = laser optical power ÷ electrical power consumption × 100%
If a laser source achieves 37% efficiency, this means that approximately 37% of the electrical energy consumed is converted into laser beam power. The remainder is lost—mainly as heat and due to losses in the power supply system and pumping modules.
At first glance, 37% may seem like a small figure, but several successive energy conversions take place within the light source: electricity powers the pump diodes, which generate pump radiation, which is then converted into a usable beam. Losses occur at every stage. Higher efficiency means that less electrical energy is needed to achieve the same optical power—and less heat needs to be dissipated by the cooling system.
Is a Raycus source efficiency of over 37% high?
For a high-power industrial fiber laser, an efficiency exceeding 37% is a good level of energy efficiency. By comparison, published data on standard fiber lasers typically show values in the range of 25–35%. A result above 37% therefore demonstrates that Raycus lasers efficiently convert the energy they consume into beam power.
High electro-optical efficiency is also one of the key advantages of fiber technology over older systems, including CO₂ sources. However, this does not mean that every fiber laser cutter automatically results in low operating costs—the outcome also depends on the laser source power, cutting time, machine utilization rate, and power consumption of other equipment.
Raycus has published the results of measurements taken on randomly selected 12- and 20-kW continuous-wave sources, taking into account the actual optical power and the total electrical power consumed by the source. However, one should not assume that every source—regardless of model, generation, or power—achieves exactly the same value. Efficiency depends, among other things, on the source’s design, pump modules, operating temperature, and load. Therefore, we should treat a level above 37% as a confirmed result for the tested 12- and 20-kW sources, rather than a single fixed figure for the manufacturer’s entire product line.
How much power do the Raycus 12 and 20 kW units consume?
Given the optical power and efficiency, you can roughly calculate the power consumption of the light source:
- 12 kW power source with 37% efficiency: 12 ÷ 0.37 ≈ 32.4 kW,
- 20 kW power source with 37% efficiency: 20 ÷ 0.37 ≈ 54.1 kW.
These are calculated values for the source itself—they do not reflect the power consumption of the entire machine. The energy consumed by the cooler, drives, CNC control system, exhaust system, compressor, and other equipment must be added to this figure. Actual power consumption also varies throughout the production cycle: the laser does not always operate at full power, and the program includes piercing, travel between contours, sheet changes, and idle periods.
How significant is a difference of a few percentage points?
For light sources with power ranging from a dozen to several dozen kilowatts, even a few percentage points of efficiency can have a noticeable impact on power consumption. For example, for a light source with an optical power of 20 kW:
| Source Efficiency | Calculated electrical power consumption (20 kW source) | Difference from 37% |
|---|---|---|
| 37% | ≈ 54.1 kW | — |
| 30% | ≈ 66.7 kW | + ≈ 12.6 kW |
| 25% | ≈ 80.0 kW | + ≈ 25.9 kW |
A heat source with 37% efficiency would therefore, theoretically, consume about 12.6 kW less than a 30% efficiency source and about 25.9 kW less than a 25% efficiency source. This difference becomes significant during intensive multi-shift operation—lower power consumption by the source also means less energy converted into heat and a reduced load on the cooling system. The calculations demonstrate the extent to which efficiency affects the system’s energy and heat requirements (they do not imply that the entire difference is absorbed solely by the cooler).
The power of the laser source is not the power consumption of the entire laser cutter
A power rating of 12, 20, or 30 kW refers to the optical power of the beam—it is not the connected load or the average power consumption of the entire machine. The total power consumption of a fiber laser cutting machine consists of several power-consuming components.
Raycus laser source
One of the largest consumers of energy during active cutting. Power consumption depends on the set power, electro-optical efficiency, and load. The laser does not always operate at its full rated power—the parameters vary depending on the type and thickness of the material, the piercing technology, and the geometry of the contours.
Laser Cooler
It dissipates heat from the source, the head, and other components. Its heat removal capacity depends, among other things, on the laser load, the temperature in the hall, the set coolant temperature, and the system design. The higher the source’s efficiency, the less energy is converted into heat—which can reduce the load on the cooler, although the ratio may not be exactly the same.
Drives and Motion Systems
Axle servo drives, lifting systems, shuttle tables, and automation. Instantaneous power consumption increases during acceleration and braking; for large working areas, the weight of the components, the length of the travel distances, and the required dynamics are important factors.
Exhaust, Filtration, and Compressor
An exhaust fan (more broadly: fume extraction and filtration) removes fumes and dust; its airflow depends on the fan’s power, system resistance, the condition of the filters, and the control method. If compressed air is used as the auxiliary gas, the compressor’s air consumption must be taken into account—since the compressor is often located outside the machine, its consumption is not always reflected in the cutting machine’s specifications (see the guide on selecting auxiliary gas for more information).
Controls and Other Equipment
CNC control systems, industrial computers, electrical cabinets, safety systems, area lighting, and material-flow automation equipment. Many of these systems also operate during breaks between active cutting operations.
Connected power, maximum power draw, and energy consumption
When comparing laser cutters, it’s important to distinguish between three values that are often confused.
Connected load
It specifies the requirements for the electrical connection and protective devices. It must account for the possible load on the entire system, which is why it is usually higher than the average power consumption during normal production.
Maximum intake
It shows the instantaneous power demand under specific conditions—it does not reflect energy consumption over the entire shift.
Energy consumption
Expressed in kilowatt-hours, this figure shows the actual amount of energy consumed over a given period. This value affects the bill and should be related to the number of parts, sheets, or batches produced. A machine with a high rated power does not necessarily draw maximum power at all times; on the other hand, low instantaneous power consumption does not guarantee a low cost per part if the process takes significantly longer.
Instantaneous power consumption does not reflect the cost of manufacturing a part
A higher-power laser can draw more energy at any given moment, but it can also complete the job in less time. Therefore, a higher power output does not necessarily mean proportionally higher energy consumption per workpiece.
Energy consumption per part = average power consumption of the entire system × part production time
While a higher-power fiber laser significantly reduces cutting and piercing times, energy consumption per workpiece may decrease despite higher peak power consumption. The result depends on the type and thickness of the material, the length of the contours, the number of holes, the assist gas, the machine’s dynamics, and the nesting. For parts with a large number of short sections, small holes, and frequent changes in direction, the machine’s dynamics—rather than the power of the laser source—can be the limiting factor; in such cases, higher power will not proportionally reduce production time.
What factors affect the energy efficiency of laser cutting?
The wall-plug efficiency of the power source is important, but the efficiency of the entire process depends on other factors as well.
Order Processing Time
The shorter the production run, the less time the heat source, cooler, exhaust system, and other equipment are in operation. A faster process may be more important than low instantaneous power consumption alone.
Selecting the Power of the Source
The power should be appropriate for the materials, thicknesses, and types of parts produced at the facility. If the power is too low, it slows down the process; if it is very high but not fully utilized, it does not always yield the expected benefits.
Technical Specifications
Incorrect cutting speed, torch position, power, or gas pressure increase energy and gas consumption without improving edge quality. The technology should ensure stable, repeatable cutting and the shortest possible cycle time.
Nesting and Material Utilization
Proper placement of parts shortens travel distances, reduces the number of cuts, and improves sheet utilization—while also affecting material costs, machine runtime, and energy and gas consumption.
Production Organization
The machine also consumes energy while waiting for material, unloading parts, or preparing a program. Efficient loading, unloading, and material flow reduce downtime and increase the number of parts produced per shift.
How can you accurately compare the energy consumption of cutting machines?
A comparison is meaningful only for the same manufacturing task: the same material and thickness, the same part layout, comparable quality requirements, the same auxiliary gas, and the same method of calculating production time. It is advisable to measure consumption at the machine’s main power supply, and to account for external equipment (compressor, nitrogen generator, independent exhaust system) separately.
Practical indicators include:
- kWh for retail,
- kWh per sheet,
- kWh per meter of cut,
- energy consumption for the entire batch,
- cost of gas per batch,
- the total cost of producing a correct part.
The most reliable criterion is not the cost of the laser source itself, but the total cost of producing a part that meets quality requirements—we discuss this in more detail in our guide to the operating costs of a laser cutter, as well as in the sections on materials and optics.
How does STIGAL analyze energy consumption and cutting costs?
When selecting a fiber laser cutting machine, we analyze not only the power and efficiency of the Raycus laser source, but the entire production process. We take into account, among other things:
- the machine’s power consumption and the operation of the power source and cooler,
- the power consumption of the exhaust fan and the compressor,
- the cost of gas in O₂ CUT and N₂ CUT technologies, and the possibility of using compressed air,
- active cutting time and the time required to complete the entire batch,
- the type and thickness of the material, the number of perforations, and the length of the contours,
- the utilization rate of available capacity and the planned number of shifts.
This allows us to compare configurations based on the estimated cost of producing the part, rather than solely on the power of the light source or a single catalog value. An efficiency of over 37%, confirmed by Raycus for the tested 12- and 20-kW sources, is a good starting point—the final result also depends on the selected configuration, cutting technology, production organization, and order turnaround time. Our product lineup includes fiber laser cutters and machines configured as laser cutters for steel plates.
Let’s calculate the actual cost of cutting your production
We’ll select a fiber laser cutter based on the type of material, thickness, and expected productivity—taking into account energy consumption, gas costs, and turnaround time, not just the power of the laser source. Let’s discuss a configuration tailored to your facility’s actual needs and costs.
Frequently Asked Questions — Power Consumption and Efficiency of Fiber Lasers
Nie. Dla przemysłowego źródła fiber dużej mocy to dobry i konkurencyjny wynik. W publikowanych danych dotyczących standardowych źródeł fiber spotyka się wartości rzędu 25–35%.
W opublikowanych przez Raycus pomiarach losowo wybranych źródeł 12 i 20 kW sprawność elektryczno-optyczna przekraczała 37%. Dokładna wartość może zależeć od modelu, generacji, obciążenia i warunków pracy.
Nie. 12 kW to moc optyczna wiązki. Przy sprawności 37% samo źródło potrzebuje obliczeniowo około 32,4 kW mocy elektrycznej podczas pracy z pełną mocą.
Nie. Parametr odnosi się do sprawności elektryczno-optycznej źródła. Nie obejmuje automatycznie chłodnicy, napędów, odciągu, sterowania, sprężarki ani pozostałego wyposażenia.
Nie. Może pobierać więcej energii w danej chwili, ale jednocześnie wykonywać detal znacznie szybciej. O wyniku decyduje pobór całego systemu oraz czas cyklu.
Wykonać ten sam program na tym samym materiale i porównać zużycie energii całego systemu, czas realizacji, zużycie gazu oraz liczbę prawidłowo wykonanych detali.
