Combi oven energy consumption:
why Rational is the most efficient choice
Energy costs are the least visible factor in a professional kitchen – and over the service life of a combi oven, the biggest. What makes Rational stand out on electricity consumption and why a used Rational from JMGT often delivers the lowest total cost.
By JMGT Commercial Kitchen Equipment · Authorised Rational Dealer · 27 May 2026
Summary
Rational iCombi Pro and Classic are the most efficient combi ovens in their class. With a new unit you combine this efficiency with low running costs. With a used Rational you combine energy efficiency with a significantly lower purchase price – an often overlooked route to the lowest total costs.
Why Rational leads on energy consumption
- ClimaPlus control
Steam and hot air are precisely dosed. No overproduction, no energy waste.
- iCookingSuite
The oven automatically adjusts cycle, temperature and time to the load.
- HiDensityControl
Even heat distribution – no cold spots, no unnecessary reheating.
- Heat recovery
Hot exhaust air is partially used to pre-heat incoming air.
- Efficient Active Clean
Cleaning cycles use only what is necessary – no unnecessary water or energy consumption.
New or used: the smarter choice
Many buyers believe energy efficiency only exists with new units. That is not true. A used Rational from year of manufacture 2018–2019 has comparable energy efficiency to a new iCombi Pro. The difference is the purchase price.
When a new unit makes sense
You combine maximum energy savings with the latest technology. With high usage intensity, the premium pays back quickly.
When a used unit makes sense
You save considerably on investment while retaining the energy efficiency of the Rational platform. For many kitchens – especially new businesses and seasonal hospitality – this is the smartest route with the lowest total costs over 5 years.
What determines your energy consumption
- Number of operating hours per day.
- Load factor – a well-filled oven is more efficient.
- Type of preparation (steam, hot air, combination)
- Frequency of Active Clean cycles.
- Water hardness (limescale damage reduces efficiency)
- Age of the unit (from 2018–2019 the difference is negligible)
Frequently asked questions
Why does a Rational use less energy than other combi ovens?
The Rational iCombi Pro is designed for maximum heat recovery, intelligent load sensors and automatic cycle adjustment. This wastes less energy during heating and cooling cycles. In practice, a new iCombi Pro consumes significantly less than older convection ovens or combi ovens from other manufacturers.
What is more efficient: electric or gas?
Electric Rational models are more efficient in primary energy consumption than gas – no combustion loss, better controllability. Electricity also combines better with renewable energy. For most new installations, electric is the standard choice.
Does a used Rational also save on energy?
Yes. A used Rational from year of manufacture 2018–2019 (later SelfCookingCenter models and iCombi series) has comparable energy efficiency to a new iCombi Pro. So you save on electricity and on purchase price.
How much does a new Rational save compared to an older model?
A modern iCombi Pro uses considerably less electricity and water than a combi oven over 10 years old. That amounts to a noticeable reduction in your energy bill each year – depending on your usage intensity. We are happy to calculate this specifically for your situation.
What is the difference between Rational and competitors on energy consumption?
Rational as market leader has the most advanced efficiency technology: ClimaPlus control for steam, iCookingSuite for automatic cycle adjustment and HiDensityControl for even heat distribution. Competitors are approaching this level, but Rational remains the reference for energy-efficient professional cooking.
Is a used unit also efficient from an energy standpoint?
Yes, definitely for units from year of manufacture 2018–2019. The energy efficiency of the iCombi platform is comparable to a new unit. You benefit from a lower purchase price with nearly identical running cost behaviour over 5 years.
Next step
Request a payback calculation based on your current consumption. We calculate both a new unit and used unit scenario – so you immediately see which route is most worthwhile.
Sources
- Rational iCombi Pro energy specifications – Rational AG
- Technical documentation Rational SelfCookingCenter – Rational AG