Choosing the right electric steam generator is not just a question of power. An oversized unit can result in unnecessary energy costs, and a small unit may not meet the needs of the process, causing bottlenecks or production losses.
In this guide we show you the key factors you need to take into account to correctly size an electric steam boiler (in other words: to get the right size of electric steam generator), ensuring performance, efficiency and reliability.
Define your industry application
Before talking about numbers, it is essential to know the specific use of steam in your process:
- Is it used for cleaning or heating?
- What type of equipment or lines require steam?
- What is the frequency of use: intermittent, continuous, shift?
- Is there more than one point of simultaneous consumption?
This data will allow you to define whether you need a compact unit for sporadic use, or a robust boiler for intensive operation.
2. Calculate the thermal demand in kW or kg/h of steam.
To get an initial estimate, you can convert the required thermal power (in kW) to steam quantity (in kg/h):
📌 Practical example:
If you need 90 kW thermal for your process:
This value gives you a reference to select a generator with the right production capacity.
3. Consider consumption peaks
Many industrial processes have peaks in demand when starting machines, starting cleaning or heating cold tanks.
Identify whether your process needs all the steam at once or in a staggered manner.
If there are frequent peaks, it is advisable to size the generator for the worst case scenario, or to incorporate a steam accumulator to help smooth the demand.
4. Apply a realistic simultaneity factor
In many industrial installations, there are several points of steam consumption: for example, different machines, tanks, cleaning valves or production lines. However, they do not all operate at the same time.
If you calculate the capacity of the boiler by adding the maximum consumption of each point, you will be oversizing the equipment, which implies a higher initial cost and unnecessary electricity consumption. This is why the simultaneity factor is so important.
📌 What is the simultaneity factor?
It is a coefficient that represents the actual percentage of simultaneous consumption with respect to the theoretical total. It helps to adjust the steam generator calculation to the operational reality:
| Type of installation | Typical simultaneity factor |
| Batch production | 0.6 – 0.8 |
| Intermittent industrial cleaning | 0.5 – 0.7 |
| Continuous processes with several lines | 0.8 – 1.0 |
| Centers with a single point of consumption | 1.0 (all used at the same time) |
🧮 Practical example:
Suppose you have three pieces of equipment that consume steam:
- Industrial washing machine: 50 kg/h
- Tank cleaning: 40 kg/h
- Sterilizer: 60 kg/h
- Theoretical total demand: 50 + 40 + 60 = 150 kg/h
But you know that, at most, only two pieces of equipment run at the same time, and rarely at 100%. Therefore, you apply a simultaneity factor of 0.75:
- 150 × 0.75 = 112.5 kg/h actual
Result: you can select an electric steam generator with a capacity between 110 and 120 kg/h, instead of oversizing for 150 kg/h.
5. Take into account the working pressure
The amount of steam produced by a boiler is influenced by the working pressure. The higher the pressure, the lower the volume of steam generated. Therefore, the higher the pressure, the lower the volume of steam generated:
Make sure that the generator is working at the pressure required for your process (e.g. 6, 8 or 10 bar).
Consult the manufacturer’s performance curves to verify the effective steam production at that pressure.
6. Consultation with a specialist
Although these calculations are a solid basis, each installation has its own particularities: types of consumption, schedules, thermal requirements, electrical availability, etc.
At Giconmes, we analyze your processes, consumptions and objectives to help you choose the optimal electric steam boiler, both in capacity and configuration. Contact us now.