By November 6, 2014 0 Comments Read More →

Electric radiators fly the flag for energy efficient heating

ElectrRadRICHARD BROWN, Managing Director of Electrorad, considers recent claims that infrared heating uses 50% less energy than most other forms of heating and argues the case for electric radiators as an all round superior heating solution.

There’s been much ado recently about infrared heating being the latest energy-efficient source of heating set to take the electric heating market by storm. The truth is that ALL electric heating products have the same efficiency – 100% conversion of electrical energy input to heat output and they ALL, infrared included, produce the same amount of heat for the same money.

Infrared heating is designed to heat the people in the room directly rather than heat the air in the room like traditional heating systems. The manufacturers or suppliers claim this means a lower wattage heater can be used. This may be true, but the heater has to be on all the time at full power to keep the room occupant warm.

For example, a 1.5kw electric radiator might be used to heat a living room and an alternative might be a 0.75kw infrared heater. The infrared manufacturers would claim this represents a 50% energy saving, but that is not the case. It cannot be disputed that the 1.5kw radiator will produce twice the amount of heat as the infrared heater but the radiator is producing both radiant and convection heat, whist the infrared heater is only ever producing radiant heat.

A radiator will also be thermostatically controlled and will switch off when the ambient room temperature reaches the thermostat set point. The infrared heater has to remain on the whole time if the room occupant wants to be warm. It is quite typical for a thermostatically controlled electric radiator to be drawing power for around 30-50% of the time in order for a room temperature to be maintained.

This means the 1.5kw radiator would use up to 750 watts per hour (depending on the room heat loss), whilst keeping the room and the occupant(s) warm, and the infrared heater will have to remain on all the time using 750 watts per hour to just keep the occupant warm. Clearly this shows that there is no energy saving from using infrared heaters over electric radiators.

The mechanisms by which thermal energy is transported by an electric radiator are convection and radiation, convection warms the air and circulates it around the room, radiation heats people and objects directly. Alternatively, infrared heaters transfer thermal energy via electromagnetic waves (in straight lines). Only objects are warmed as opposed to entire areas.

Air temperature

Infrared heating relies totally on radiant heat to heat the surroundings and infrared waves travel through space and are absorbed by people and objects in their path. Infrared is not absorbed by the air through which it travels. It’s true that householders feel warm when the infraredheat is turned on, but once it is turned off, they will almost immediately feel cold as the air temperature remains cold.

Electric radiators warm the air from beneath the heater and, by using natural convection currents, circulate the warmed air throughout the room. They also produce radiant heat to warm the occupant directly. In all models, the warmed air circulates into the room, raising the ambient temperature. When the heater’s thermostat setting has been reached, the heating element is shut off. When the room air cools again, the thermostat will trigger the unit to turn on.

In my view, infrared heaters simply cannot compete with some of today’s sophisticated electric radiators which, as well as being safe, reliable and easy to install, present a sensible and economical alternative to gas and oil. Not just that, but visually, they are a far cry from the storage heaters of yesteryear.

Today’s electric radiators offer a high level of comfort with increasingly sophisticated controls that enable all round warmth and comfort, tailored to suit individual preference both by unit and by room, and by controlling both temperature and time of use. This facilitates the ultimate in control of energy usage and efficiency.

Competition is healthy and it’s good to welcome new forms of heating on board. However, we need to continue to raise our game by educating the home-owner.