Wood as a natural source of energy
Is it good to use wood and timber products?
Recent studies show that old growth forests continue to absorb CO2 at rates nearly as fast as new growth forests for hundreds of years [resurgence.org]. That statement shows clearly that it is good to keep native forests and bushland untouched and if it is not for CO2 reduction then think about how many people use national parks and forests in their spare time for recreation. Also remember that the forests and especially old growth forests contain our invaluable wildlife and plant species that we will lose forever if we lose these forests.
However, wood is a renewable resource and it should clearly be treated as such. Wood should be used as building material and as energy resource. All harvested areas in Australia are regenerated and regrown [National Association of Forest Industries Australia]. That in mind it is harmless to use Australian timber products. And a lot of timber used to build houses, timber decks or to manufacture furniture, doors or staircases means a lot of latent carbon and therefore a lot of restrained CO2.
However, forests and wood areas destroyed by land clearing for farming land or development and extension of towns are not regrown yet. That means Australian forest regions still shrink where it is really so important to enlarge these areas and that happens just because of thoughtless destruction of bushland and forests and is not caused by the utilisation of wood.
By using 1 kWh of wood energy, 0.3 kilograms of carbon dioxide is released into the atmosphere. 0.3 kg of CO2 contain 0.08 kg of C (carbon) and that is stored in a 0.18 kg light peace of dry wood. In other words a 1 kg log of (completely dry) wood contains about 5.5 kWh of energy.
After using timber as a building material it is frequently recycled and used again. Wood often binds carbon for several hundreds of years and if it cannot be reused anymore then wood is still a source of energy and it won’t emit (release) more greenhouse gases than it had once sequestered (absorbed). Combusting of fossil fuels like coal and gas means however, turning carbon reservoirs into carbon dioxide which have been developed millions of years ago.
Is it wise to use timber as a building material?
Virtually any industrial production process uses energy and therefore emits CO2 into the atmosphere. Fabrication processes of steel, concrete and even wood use energy and stress the environment. Wood however still holds a lot of carbon bound to it whereas other building materials do not contain such a high amount of carbon.
Each cubic meter of wood that serves as a substitute for other building materials, reduces CO2 emissions into the atmosphere by an average of 1.1 tonnes of CO2. That added to the 0.9 tonnes of CO2 that are stored in wood, you get a total of 2 tonnes of CO2 reduction by each cubic meter of wood [research, Arno Frühwald University Hamburg, Germany].
Using timber as building material is always reasonable. Trees grow basically everywhere and that saves long supply routes. Not only residential houses can be made of wood: multi-storey commercial and leisure buildings, warehouses with huge spans, bridges, etc.
In addition, wood is the lightest material that has good insulating capacities at the same time and such high strength that it can be used for load-bearing parts. Wood is therefore in every aspect, from an environmental and economic point of view, the building material of choice.