Australian Passive Solar Home

One aspect of energy-efficient house design that I think these days is often missing in action is the idea that we should heat people, not houses. This is best exemplified by the use of personal heaters versus whole of house heating. Personal heaters heat people; whole of house heating heats empty rooms, the food in kitchen pantries, the books on shelves – everything.

One of the best personal heaters is a radiant design. This works extremely effectively because so much heat transfer that we, as humans, have with the environment is via radiant heat transfer. When a person is stationary, e.g. sitting at a desk, a radiant heater positioned under that desk is economical and highly effective.

One reason for its effectiveness is shown here – the radiant heat transfer is so great. The measured air temp under the desk is 23 deg C; the radiant temp (as measured by the black body thermometer) is 32 deg C. Very toasty.

Radiant heaters also work well in bathrooms – lots of naked flesh.

As ‘top up’ heaters, when physical activity and/or clothing levels are low, personal radiant heaters provide good comfort – and they don’t heat empty spaces.