Wood – Fuel of the Future

BACK  to Künzel                          Back to Info page

 

The use of wood for heating
purposes ?

You may ask yourself, "what, if any, are the advantages of using wood for heating purposes?" There are several arguments in favour of this:

  • Wood 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.
  • Depending 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.
  • The 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.
  • Pure 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.
  • This 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 house effect

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

green_house_effect
The green house effect

and 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 and Photosynthesis

  wood_burning_renewable_energy
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, Bonn/Bad Godesberg

BACK