We’re having a heater debate here at the Project 90 office, as winter slowly approaches. Our office is freezing in winter, and despite dressing warmly (hats, gloves and scarves!) we still have a need for heating. Our office has panel heaters as well as gas heaters and we have been debating which is the most carbon efficient way of heating our office. Does it make sense to use the panel heaters when it means having to leave them on overnight to keep the room warm. I remembered that Gary Fahy wrote an article comparing different types of heating, and have re-posted it here. It makes for interesting reading.
Robert also reminded me of the importance of ceiling insulation in keping your home warm. The new building standard prescribes for houses in the Cape Town region a thickness of insulation material up to 140mm, depending on the make. The costs are not much, we paid around R1,800 to have our office ceiling insulated. The benefits however are very much dependent on what else you do or have. If your doors and windows have huge gaps and the floors are tiled on concrete without any insulation than the house will still continue to be very cold.
Gary Fahy on household heating:
This month I have investigated a variety of common household heaters in an attempt to evaluate the costs, and more importantly, the resulting CO2 emissions associated with their use. This might have come a little late in the year, with spring on our doorstep, however the same information will apply next winter. First off we should note that the effectiveness of a heater is very dependent on the environment in which it is being used, and for this reason I believe laboratory tests are not very informative. This article is simply to illustrate the actual cost of using a certain heater, and the resulting CO2 emissions, and I leave it up to you, to evaluate which heater performs better in your environment. I have looked at various wall mounted panel heaters, LPG or Gas heaters, fan heaters, element heaters and oil fin heaters, and these are my findings.
Wall mounted panel heaters are often touted as the most cost effective and energy efficient means of heating and generally consume around 420W of power. Using this heater for an hour would result in 0.5kg of CO2 emissions and cost about 25c at today’s electricity price. I have one of these panel heaters in my bedroom, and from experience it is only effective if left on for a long period of time, and the bedroom door needs to remain closed. This type of heater would not be effective in a large, draughty living space.
LPG (Gas) heaters typically have three panels, each the same size and each emitting the same amount of heat. I also own one of these heaters and very seldom use more than one panel. Using the heater on its lowest setting for 1 hour, which is typically how long it takes to heat my living room to a comfortable temperature, consumes about 1.2kW of power. Burning this amount of gas emits approximately 0.3kg CO2, and costs approximately R1.80 an hour. This might seem like a lot, however the heater is very effective in heating the room up and I seldom need more than an hour or two. Multiply this by 2 and 3 to get values for medium and high settings respectively.
Fan/element heaters and oil fin heaters are typically rated at about 2000W, which means they consume about 5 times more electricity than panel heaters. So using one of these heaters for an hour is going to result in 5 times more CO2 being emitted, and a whopping 8 times more than the gas heater on its lowest setting! They will cost you almost 5 times more than wall panel heaters per hour, and only slightly less than a gas heater.
In a nutshell, a gas heater costs only slightly more than fan/element and oil fin heaters to run, but emits about 10 times less CO2! Compared to panel heaters, gas heaters cost about 7 times more to run, but result in about half the CO2 emissions. So if you can afford it, a gas heater is much more environmentally friendly, and in my opinion, much more effective in certain environments.
I therefore suggest a gas heater for a large living room area, with people coming in and out all the time, and wall mounted panel heaters for bedrooms, where less intense heating is required and where there is not a lot of traffic through the room. They are quite effective in closed spaces, and do not use up oxygen so safe to leave on while you sleep. Which brings up a very important point: when using a gas heater, always ensure the room is well ventilated. This might seem strange since you want to retain heat, but gas heaters consume a lot of oxygen, and without a constant supply, it will result in a dangerous build up of carbon monoxide. Never use them in closed confined spaces.
That said, burning wood sourced from well controlled and sustainable forests, or from alien species clearing, is still first choice since it is essentially carbon neutral, and let’s face it, much nicer to sit in front of. So throw out the old oil fin and element heaters, grab a glass of wine and chuck a few logs in the fireplace.
Note: the CO2 emissions calculated for gas heaters did not include emissions through the entire lifecycle of LPG, i.e. manufacture, transport and distribution to the point where it was being used in my heater. They were simply based on the amount of gas consumed, however the results are still indicative.
© Gary Fahy, August 2009