Radiant Heating vs. Convection Heating

There is a persistent misunderstanding about what it means to heat a space. We often imagine that comfort comes from raising the temperature of all the surrounding air. That is the logic of convection heating, familiar from radiators, fan heaters and many indoor systems. It works in enclosed, insulated rooms. In open, high or ventilated areas, it quickly becomes the wrong approach.

What convection does, and where it reaches its limits

Convection heating warms the air. Warm air is lighter than cold air, rises, circulates and gradually evens out the temperature of an enclosed room. In a bedroom, office or well-insulated classroom, this principle is effective because the heated air remains inside the volume.

The same logic becomes inefficient in high-ceilinged rooms, halls and large open spaces. Warm air rises to areas where nobody is sitting or standing, while the occupied zone remains cooler. Energy is spent heating a volume that does not directly create comfort.

Outdoors or in semi-open spaces, the limitation is even clearer. There is no closed volume to heat. The warm air produced by a convector is dispersed by the slightest air movement, so additional power rarely translates into stable comfort.

Infrared radiation: another way to think about heat

Radiant heating follows a different logic. It does not try to heat the air first. It emits infrared radiation that travels through the air and becomes heat when it reaches solid surfaces: floors, walls, furniture and, above all, people within the heated zone.

This is the same principle that makes sunlight feel warm on a cold day. The air may remain cool, but the body receives heat directly. A radiant heater reproduces this effect in a controlled, localised and predictable way.

For terraces, pergolas, balconies and professional outdoor spaces, this changes the whole equation. Wind and air renewal matter far less, because the comfort is delivered to the occupied area rather than stored in the air.

Different heat zones: a practical advantage

Radiant heating makes it possible to create distinct comfort zones within one larger space. Convection tends to treat the whole volume as one unit; infrared radiation can be directed and adjusted according to the areas that are actually used.

A restaurant terrace can heat occupied tables without wasting energy on empty zones. An event venue can warm a reception area without heating circulation paths. A semi-open hall can maintain comfort near a counter or entrance without trying to heat the entire building volume.

Operating cost: the difference is easy to understand

The economic comparison often confirms the technical one. A gas patio heater can consume around 900 grams of gas per hour. Based on a typical 13 kg gas bottle, this can represent roughly 2.25 euros per hour, with the added constraints of storage, handling and bottle replacement.

An electric radiant heater rated at 2,800 W, with electricity at 0.20 euro per kWh, costs around 0.56 euro per hour. Local tariffs vary, but the order of magnitude is clear: for intensive use, electric radiant heating can be far less costly to operate than gas.

There are also practical gains: no gas bottles to store, no empty bottles to manage, no combustion appliance to service in the same way. The heater switches on, heats the target zone and switches off.

A solution aligned with today’s expectations

The choice is not only technical or financial. For restaurants, hotels, leisure venues and businesses welcoming people outdoors, heating also says something about the quality and responsibility of the place.

Electric radiant heating, especially when supplied by low-carbon or renewable electricity, fits more naturally with current expectations around energy use, comfort and discretion. It is not a trend; it is a technical answer to situations where convection simply cannot perform well.

Key points

• Convection heats the air.
• Radiation heats people and surfaces.
• Infrared is more suitable for open or ventilated areas.
• Hourly running cost can be much lower than gas.
• The solution is more coherent with current energy expectations.