Interview with Phil Alcock, FRICO MD - Infra Red Heating

In the last blog entry - Phil and I were discussing using infra heating as a total house / office heating system, and comparing radiant heating with gas central heating, and ground source heat pumps.  In this article we will look at the various applications for infra red heating, the difference between infra red and radiant heating, and energy savings.....

So how long will an infra red heating system last?

The shelf life of the system once installed will be the life of the building and we certainly know that other electrical appliances are still going strong even after 20 years of running quite happily and they run at much higher stress loads (take your dishwasher/washing machine).

Commercial environments differ somewhat in that there are things to consider like damp and corrosion, so a commercial system might last 15 years but it is in a much harsher environment

We supplied one of the major zoo’s lions dens, what sort of other interesting projects have you seen?

We have done a number of projects for zoos and their reaction to radiant heating is exactly the same as humans.  Because radiant heating is the natural form of heat - we always say it is like heat from the sun - most animals that live on the planets are designed to keep warm and comfortable with radiant heat, so as well as heating animals from the Savannah like lions, we’ve heated snake and reptile enclosures, and  we’ve heated alligators enclosures where the animals and reptiles bask in the radiant heat environment. 

It is very effective.  And, another advantage with using a radiant heating system in a zoo is they don’t emit visible light so the animals stay warm but they don’t get the impression that it is daylight 24 hours a day!

We’ve spoken about using the heating system in sports halls, yoga studios, modern gyms – with regard to sports halls we recently made a large installation in France in a judo stadium with a very high roof, and the challenge with judo and indeed hot yoga is that at floor level the mats need to be warm, and to an extent need to be kept dry – although I’m not sure in judo whether that is meant to be dry from sweat or blood but it is certainly needed to be kept dry, and the infrared heating (as well as keeping the occupants warm) keeps the surfaces warm – so  if you have a yoga studio, you not only keep the participants warm but their exercise mats are comfortable as well.

We put infrared heating systems in halls as the classic problem there is that the village hall is used in the evenings and a just few nights a week and the rest of the time it is off.  The yoga instructor comes in to find the building stone cold, switches an infrared heating system on and within a few minutes the heaters are up to their full temperature emitting heat, you can put your exercise mats down and immediately feel warm, so we do a lot of those sorts of applications because they are away from conventional sources of heat and are only used periodically. 

We also use a lot of radiant heating for outdoor heating smoking areas for restaurants and public seating areas where they wants to maximise the use of the drinking or eating area. Process and industry favour infrared heating for example in warming plastics as they travel along the production line.  We did some work with one of the major car manufacturers where they manufacture components, and if the factory is cold, making the plastic panels fit in to their surroundings gets very hard and can become brittle - they need a heating system to keep the plastic a little bit soft and pliable.  I could go on and on, but there are many many applications for infrared heating.

You mentioned radiant and infrared - what is the difference between these two terms?

It is the same thing - a lot of the terminology being used is referring to radiant heat, infrared heat, you’ll see FAR infrared, particular an American terminology yet the heating is always infrared heat – the basic physics are that any ‘body’ be it human or any other hot surface – as soon as it gets hot, will start to emit infrared energy, which is the energy that we use.  It is an electromagnetic wave that is part of the lighting spectrum, but it is at a very low level so you can’t see it when the ‘body’ gets hot. As an example, when a hot cup of coffee gets hot it will start to emit infrared energy, but we don’t see it necessarily.

So we’re emitting energy all the time?

Yes and most people are familiar with that, as most people will have seen infrared cameras – like the thermal imaging cameras police use on the police stop programs, this is showing the thermal signature of the human body, it picks up the spectrum of light from the body. Humans can’t see it, but some animals can and use it to hunt, but we can’t see it – but that is all we really need to know.

From a technical standpoint, on the infrared spectrum we can move from long wave infrared which produces heat energy but no light, and as we increase the surface temperature of that heat emitter we get to a point where it can be seen as visible light by the human eye - that comes at about 700⁰C and when an object gets to that temperature it begins to glow. We can see it glow from the heaters that we see outside the pubs and bars – essentially it is all infrared heat and all radiant heat so the two terminologies are interchangeable. 

Thank you for clearing that up.  Building consultants are looking to make savings – have you any reassurance you can give them?

Most building consultants and people who design buildings are certainly familiar with the concept of radiant heating and it’s nothing new.  It’s something that has been around for a very long time.  What is changing is the number of applications and the number of products that we can use, which have improved a great deal. 

Control systems have improved a lot and building standards have improved a lot as well – making very well insulated properties.

The reassurance that we can offer energy consultants is to point to case studies and calculations - it is very easy to use the FRICO Heat Output Calculation Tool that we have on our website to work out the heat loss of the building.  It is very easy to put the details through online tool and one of the parameters you change when doing the calculation is from infrared heating or convection heating.

One of the main areas of energy saving is that you have very little high heat build up with infrared heating.  What this means is that with a convection system the warm air rises, and all of that hot air at the top of the building has cost money to heat so when you design for a warm air convection system you have to allow for that discrepancy and to allow for say 21⁰C at person height where you are sitting and 27⁰C at ceiling level.   You would have to pay for that energy and on a calculation simulation we can easily show the difference between the radiant heating and the convection heating.  With the radiant heating there will be less than a 1⁰C difference between the air temperature at floor level compared to ceiling level and that is where is translates in to an energy saving.

More to come on infra red heating.....