Understanding Heating

How new technology cuts your heating bill

Posted on 4/29/2013 by Lifestyle Fires

Heating technology has improved remarkable over the past years, as demand for better utilisation of our natural resources has increased. But how does it work, and how will it save you on your heating bill?


Whilst renovating their homes, most home owners will look at how best to heat their home, for both space and water heating and how to cook their food. Increasingly home owners are looking at systems that don’t rely on scarce (and rapidly increasing in price) electricity, are economical to run and environmentally sound. There is still a desire to have a heating system that looks good and provides visual appeal. In short a fireplace.



Traditional wood/anthracite fires of the open brick variety look good but have very low efficiencies and heat outputs. About 5% of the energy in the wood is converted to heat inside the house. They usually heat one room only and at considerable wood consumption. They will burn out about 2 to 3 hours after refueling, so they do not have the ability to keep the house warm overnight. The permanently open chimney sucks heat out of the house 24 hours a day, whether the fire is lit or not. These unlit fires often substantially reduce the effectiveness of other forms of heating, by allowing heat to escape. Steel damper units can be fitted into the chimney giving some control over heat losses up the chimney. However overall efficiency and heat output is low.

Manufactured steel boxes that either fit into the brick chimney or are designed as a free standing unit are more efficient than the brick fire, generally running at 10 to 20% efficient. Typically this type of fire will heat twice the area of the open brick fire.


These fires are made of steel or cast iron and have a pane of glass closing off the front of the fire. The combustion air is drawn in through adjustable vents, which allow the rate of burn of the fire to be controlled. Some models will have a burn time in excess of 12 hours at low setting, brilliant for keeping a house warm overnight or whilst the occupants are at work. Efficiencies of these units range from about 60% to in excess of 85%. They use considerably less wood than the open wood fire, give much more heat output and are controllable. The more efficient units have a vermiculite jacket inside the fire and some of the air feeding the fire preheated. This raises the combustion temperature of the wood to in excess of 900 celcius. At these temperatures the fuel burns very cleanly giving very little in the way of emissions and vast amounts of heat. These units can heat areas up to about 170 sq metres at a cost of about R3000.00 per winter. The most economical heating system out. Closed Combustion Wood Stoves are the heating system of the future. If you plant a tree to replace the tree cut down, you have a perpetual fuel source. The growing tree will take between one and three times as much carbon out of the atmosphere as the tree you are burning will produce.

Comparative Fuel Costs

The cost comparison below is for Space Heating of Domestic Dwellings.

Heating Group Approximate Cost per Kwhr
Open Wood
Wood Stove
Flued Fire
Flueless Fire / Heater
Balanced Flue Fire

* Excludes Connection Fees

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Posted on 4/29/2013 by Lifestyle Fires