may ask yourself, "what, if any, are the advantages of using
wood for heating purposes?" There are several arguments in
is the oldest fuel we know. It is capable of surviving any crisis
and is likely to persist even if other sources of energy (oil,
gas, uranium) should be used up or prohibited in the future.
on where you live, wood may be the only fuel available within
close proximity to you. It is easy to prepare for burning and
makes you independent of external fuel suppliers.
calorific value of wood varies from one type to another. However,
we can calculate that 1 m³ of firewood (20% residual humidity)
provides the same amount of heat as 200 litres of heating oil
or 200 m³ of natural gas.
wood ash, the residue of the burning process, contains a number
of mineral aggregates, including phosphorus, sodium, calcium
and magnesium. Pure wood ash is a useful fertilizer for your
garden - in this connection one can almost say that the raw
material wood can be recycled completely.
leads us directly on to the basics of environmental protection.
Wood is one of the few fuels we know with a low sulphur content.
The burning of wood therefore produces very little sulphur dioxide
- a substance which is thought to be one of the main causes
of acid rain.
Wood and the green
To clarify this theme, we need to go deeper. If fuels containing
carbon (not only coal, crude oil, natural gas, but also organic
substances such as wood and straw) are burnt, they inevitably
produce carbon dioxide (CO2). This invisible gas, together with
other trace gases, forms part of the Earth’s atmosphere
The green house effect
ensures that most of the heat radiated by the Earth is reflected
back to its surface. The Earth’s long-wave heat radiation is produced
by converting short-wave sunlight. Through this process the Earth’s
surface and the lower air layers are heated to an average temperature
of 15°C - the essential prerequisite for any life on earth (natural
green house effect).
We currently burn too much fossil fuel and therefore produce more
CO2 than can be absorbed by the oceans and our natural vegetation.
This causes an additional green house effect. As a result, the
Earth’s temperature is rising, with unforeseeable long-term consequences
for our climate and our environment.
All consumers, including
the owners of central heating systems, are encouraged to help
reducing CO2 emission to an absolute minimum and/or closing the
CO2 cycle. The latter can be achieved by heating with wood since
it involves the process of photosynthesis.
Wood burning renewable energy
and locally grown
Through the process of photosynthesis, CO2 is re-introduced into
the natural cycle. As they grow, trees and plants absorb carbon
dioxide (CO2), minerals, water (H2O) and sunlight, in return releasing
oxygen (O2) into the environment. The burning of wood does release
CO2, but, as we said, this is re-absorbed by trees and plants
as they grow. Finally, the cycle is closed by the residual wood
ash when it is used as fertiliser. The carbon that is released
into the atmosphere by the burning of other fossil fuels, like
oil and natural gas, was not absorbed millions of years ago when
these fossil fuels originated. Unlike wood, these fuels do not
fit into the natural cycle. It is fair to say that wood, when
used sensibly, is an environmentally friendly heating fuel. (It
should also be mentioned that the pure wood burning process does
not produce any toxic chlorine compounds or heavy metals).
However, if the heating is to be environmentally friendly, it
is very important what system is used and how efficiently the
wood is burnt.
With the development of the wood-gasification boiler we have achieved
a successful synthesis. It ensures maximal use of the environmental
advantages of wood as heating fuel and combines comfort, safety
and energy utilisation to the highest degree.
Reproduction of illustrations with the kind permission of CMA,