The use of renewable sources of energy is a positive gesture for the planet. In addition to being a renewable energy source, firewood does not contribute to the greenhouse effect when burnt. Nevertheless, not all kinds of firewood have the same heating qualities. We can distinguish between two main types of wood:
Hardwoods
Coming from slow-growth trees such as oak, beech, ash, cherry, maple, chestnut, olive, elm, etc., this wood is slow-burning and offers high heating characteristics. Such wood is ideal for keeping the fire going over time, burning with a clear and continuous flame.
Softwoods
Coming from trees from the conifer family, such as fir, cedar, birch, alder, etc. Ignite rapidly and can be used to light or relight a fire. It is better to avoid the use of resinous woods such as firs, pines, etc., as they contain resins that cause smoke and blacken fireplace and wood stove glazing.
Firewood
Use larger pieces of firewood for slower burning, when less heat is needed, or for maintaining the fire overnight. Always load large pieces after the fire has been burning strongly with smaller pieces, when the unit is already at a high temperature. Smaller pieces of firewood should be used to achieve a more strongly burning fire. Load them after starting the fire for a faster response, when more heat output is desired.
Moisture
The lower the moisture content, the greater is the energy efficiency.
Good heat output and energy efficiency is closely related to the moisture level of the firewood. It is very important that the firewood to be used has been dried for two to three years and stored in a well-ventilated place. Recommended maximum moisture level – 21%.
How to recognize dry firewood
- Cracks can be seen on the surface of the trunk or branch
- The bark easily comes off
- A dry sound is heard when striking the wood