Over the past winter we’ve been bombarded with messages about the increasing cost of electricity. Craig Kelly MP, Chair of the House of Representatives Standing Committee on the Environment and Energy, at one stage warned that ’people will die’ because they can’t afford to heat their homes.
The response to the increasing electricity prices from both the federal government and the media has been to focus almost all attention on identifying ways to reduce the price of energy. Little effort appears to have been made by these parties to find different ways to tackle the problem.
Rarely do we hear about the introduction of policies designed to help people, particularly those with limited means, reduce the amount of energy they use to keep warm inside their homes.
Commercial interests and academics interested in low energy heating invariably promote a standard potpourri of measures: heat pumps, insulation and draught proofing.
This is fine as it goes, but installing heat pumps and serious insulation are expensive options which are not open to people with limited resources. As a general rule, these options are also not available to anyone who is living in rented accommodation.
But there are alternatives.
My family’s experience over the 2017 winter would suggest there are extremely effective ways to keep warm at home which are much less costly. ‘Less costly’ in this context means not only spending less money on fuel, but also spending less money on insulation and on heating devices.
I think it is important to recognise that a person may opt to buy a cheap heating device (eg a fan heater) but unknowingly end up with very large electricity bills due to the device’s high power rating (eg 2,000W).
Alternatively, they may be aware of the high power rating and may opt to use the cheap device sparingly in order to save energy – but they would sacrifice thermal comfort in the process.
I am primarily interested in both consuming less energy, and maintaining thermal comfort, by using what I call ultra-low energy heating devices – those with a power rating of say 100W and less.
Almost exactly a year ago I wrote an article which appeared in One Step Off The Grid spelling out the ideas I’d developed over the 2016 winter as we heated our Canberra home.
At that stage, I’d moved on from ‘space’ heating to ‘personal’ heating and was looking at using personal Far Infrared (FIR) heating panels with a power draw of around 400W to provide us with individualised heating.
Over the 2017 winter my thinking evolved further. I wanted to see if we could be nice and warm while we used virtually no heating energy and I began to look for ultra-low energy personal heating devices.
I had in mind the fact that the closer a heat source is to your body the less energy input you need to keep warm – I was essentially searching for devices which heat through conduction.
In order to examine the potential of these devices we deliberately did not heat our house over winter 2017 – the air temperature in our living areas in the evening was typically around 13⁰C.
When I began my journey of discovery I soon found that there is quite a large number of devices on the market which fall within my ultra-low energy definition and I went about buying and trialling some of these.
I have written up my findings in a report which I have entitled ‘Heat Yourself: Not Your House – The low-cost way to keep warm at home’.
Some of the devices I bought worked really well, while others did not seem to have any applicability to use in the home.
By trial and error we found that simple devices like heated seat pads and foot warmers (see the photos) give heating effects that far exceed what one would expect – these cost around $50 each and have a power draw of approximately 20W. I was surprised to find that applying heat to one part of the body can give wonderful whole of body thermal comfort.
The beauty of personal heating is that it can be personalised to match the thermal preferences of each member of a household.
For example, I found that with enough layers of the right type of clothing I could be beautifully warm sitting for long periods without any input of electricity.
On the other hand, my wife, who feels the cold much more than me, generally used a personal FIR heating panel and a heated seat pad, in addition to her warm clothing, to stay comfortable in the evenings.
Over the whole of the five-month Canberra heating season in 2017 we used about 90 per cent less energy for heating than we used three winters ago when we were heating our house with a ducted gas system. We were very nicely warm over winter 2017.
One very important benefit of adopting personal heating, particularly if it involves use of the ultra-low energy devices based on conduction, is that it largely negates the need for the high levels of insulation and draught-proofing that are fundamental requirements for efficient space heating.
We consistently found over winter that when using a personal heating device the level of our thermal comfort was more or less independent of the room temperature.
In summary, I believe our experience has demonstrated that it is possible to stay warm inside a house using personal heating devices drawing less than 100W, even when room air temperatures are low.
Report: Heat Yourself: Not Your House – The low-cost way to keep warm at home (https://www.slideshare.net/davesouthgate/heat-yourself-not-your-house)