The Fireplace Shoppe sells and installs closed-system wood burning fireplaces from a number of manufacturers, including Morso, Blaze, Franco Belge and Godin.
Closed-system fireplaces are highly efficient – in other words, the fuel is converted to heat with minimal losses or smoke emissions.
Fireplace units using different fuel types have very different heat outputs. Operating costs of fireplace units should be compared taking account of heat outputs, fuel costs per hour and fuel costs per kWh.
The tables below compare typical units using different fuel types in terms of the above measures. The costs are based on current prices of particular suppliers in the Johannesburg region. Costs will vary depending upon the fuel supplier and the geographic region. All costs are subject to escalation, unfortunately at different rates for the different fuel types. The tables provide a comparison at April 2011.
Fireplace units with larger heat outputs (for larger volumes to be heated)
| Fuel | Assumptions & notes | Typical heat output of fireplace unit | Approx fuel cost | Approx cost per kWh |
| Wood (in closed system fireplace) |
|
8 kW | R2,09 per hr | R0,26 |
| Bottled gas LPG |
|
|||
| Heat & Glo SL550 | 5,5 kW | R8,67 per hr | R1,58 | |
| Efficient open gas fires | 5 kW | R17,33 per hr | R3,47 | |
| Less efficient open gas fires | 5,5 kW | R20,00 per hr | R5,20 |
Open fireplaces burning wood and/or anthracite are not included above as there is little demand for these units at present. An open wood/anthracite-burning fireplace is considerably less efficient than a closed system fireplace.
Wood-burning closed system fireplaces are the most cost efficient by any measure. Heat & Glo gas units are significantly more cost efficient than open gas fireplaces.
Fireplace units with smaller heat outputs (for smaller volumes to be heated)
| Fuel | Assumptions & notes | Typical heat output of fireplace unit | Approx fuel cost | Approx cost per kWh |
| Bio-fuel |
|
2 kW | R20,23 per hr | R10,12 |
| Electricity
|
|
2 kW
(see note below) |
R1,20 per hr | R0,60 |
The electrical costs above are obviously for electrical input, not heat output. The efficiency of the appliance will determine the heat output. Nevertheless, it is clear that electric fireplaces are the most cost efficient for small areas/volumes.
The choice of putting another log on the fire or turning up the central heating a couple of degrees has a significant impact on the environment far beyond just keeping us warm.
Wood as a fuel is environmentally friendly as wood consumes more carbon dioxide whilst growing than it emits during burning. It is also one of the very few fuels that is renewable during our lifetimes.
If using wood from a sustainable source, the pruning and harvesting of woodlands not only provides fuel for fireplaces but also promotes the growth of healthy trees that can absorb up to three times as much carbon dioxide as is released when the wood is burned. Because of this, The Carbon Trust recognizes that wood is the only “zero rated” fuel available.
The following chart formulated by The Carbon Trust gives examples of how many kilograms of carbon dioxide is emitted into the atmosphere from the average family home in the UK.
| Fuel | Kilograms of carbon dioxide per week |
| Electricity | 128 |
| Coal | 116 |
| Oil | 88 |
| Gas | 63 |
| Coal/wood (50% mix) | 58 |
| Wood | ZERO |
For more information on The Carbon Trust, please visit their website www.thecarbontrust.co.uk
Reference: Franco Belge catalogue
Cast iron is one of the best suited materials for fireplaces for the following reasons:-
Cast iron does not distort. This means that regardless of how many times you fire it up the integrity of your fireplace is maintained and the cast iron door of your closed system fireplace closes tightly every time. The point about tight closing of the door cannot be over-emphasized: the door must close tightly for efficient operation of your fireplace.
Cast iron is especially suitable for fireplaces because it retains heat for a much longer time and emanates an even and pleasant warmth for a long time after the fire has died.
There is no danger of cast iron being burnt through. Cast iron has proved to be more durable under high temperatures than other materials.
Unlike steel, cast iron can be moulded into a large range of textures and designs. Hence the range of aesthetically pleasing cast iron fireplace designs from Morso and Franco Belge.
Additionally, many models of cast iron fireplace have flat tops, and will allow you to place cooking pots on top, directly above the fire. They don’t produce very high heat for cooking, but they will slow cook your food.
Sources: catalogues of Morso SA and Franco Belge
According to The Observer (25 January 2009):-
Wood is cleaner than coal and oil, emitting no sulphur dioxide and destroying dioxins through heat.
In 2003, an Australian study on greenhouse gas emissions from domestic woodheating showed that burning wood produced up to 10 times fewer greenhouse gas emissions per unit of heat than other sources.
So: Wood is the right fuel to use to minimize our carbon footprint!
Sales of closed system wood-burning fireplaces/stoves are outstripping sales of traditional open fireplaces. In fact The Fireplace Shoppe sold only a handful of open fireplaces in 2010. We can be thankful for this swing as closed system fireplaces are much more efficient than open fires. Closed system fireplaces are at least 75% efficient compared with the efficiency of open fireplaces of around 10-20%. This means an open fireplace will consume between 4 and 8 times more logs than a closed system fire.
So: Closed system wood-burners use significantly less fuel than open fireplaces!
Conclusion: in order to avoid leaving dirty great carbon footprints in heating our houses, we need to embrace the swing to closed system wood-burning fires!
http://www.guardian.co.uk/environment/2009/jan/25/eco-wood-burning-fires?intcmp=239
Morso and Franco Belge closed system wood burning stoves have been engineered through exhaustive testing in their R&D sections. To obtain the best performance from your quality unit, it is important to know the purpose of each of the air inlets to the unit and which are controllable.
Closed system wood burning stoves have primary and secondary air inlets and some also have a tertiary inlet.
On some units, the primary inlet control is located at the bottom of the unit with the secondary air inlet control located at the top. On others, the controls for the primary and secondary inlets are combined at the top of the unit.
The primary air inlet is controllable by the user. Its purpose is supply maximum air inflow to the unit when starting the fire. Once the fire is burning well, the primary air inlet should be closed down to maximize the efficiency of the burning of fuel.
The secondary air inlet is also controllable by the user. Once the fire is burning well, the secondary inlet can be used to control the heat output of the unit.
The tertiary air inlet, when a unit is fitted with such an inlet, is not controllable by the user. Air from this source is injected at the back of the fire box. Its purpose is to maximize the efficiency of burning of fuel (and thus to maximize heat output of the unit). This air inlet will marginally increase the consumption of fuel.
Remember to open the primary air inlet when starting the fire, and to close it once the fire is burning. This increases the efficiency of closed system wood burning stoves and ensures that the fire box temperature is high enough for secondary combustion of the smoke and gases.