Wood as a Renewable Energy

Wood as a Renewable Energy

Provided that the following basic rules are followed wood can truly be described as 'solar energy in a package' and thus a source of renewable energy. The basic rules are that:

When wood is burned in the presence of oxygen it produces carbon dioxide. Carbon dioxide is one of the main greenhouse gases responsible for climate change. However, the amount of carbon dioxide released is no greater than the amount absorbed by the tree when it is growing, providing that the above rules are followed. For a simple illustration of how the carbon cycle works see below.

Even allowing for emissions of CO2 in planting, harvesting, processing and transporting the fuel, replacing fossil fuel energy with wood will typically reduce net CO2 emissions by over 90%.

Sustainable Sources of Wood

A sustainable source of wood is very important if the carbon cycle is to remain intact.

Sustainable Sources of wood include wood that is

a. Forestry Stewardship Council (FSC) certified
b. From woodland managed under the Woodland Grant Scheme (which is run by the Forestry Commission)
c. Felled after the issue (by the Forestry Commission) of a Felling Licence

A Felling Licence can only be issued if the felling is approved 'in accordance with Government policy for the sound management of a renewable resource.' (UK Forestry Standard).
A felling licence is required to fell more than 5 m3 of timber (equivalent to 3-5 large trees) in any four-month period. A felling licence isn't required to fell trees in woodland already being managed under a Wood Grant Scheme; if the trees are below 8 cm in diameter at 1.3 m from the ground; or if they are dead, dying or dangerous.
If an individual tree has a Tree Preservation Order attached to it, then felling would normally have some replanting condition attached to it.

Other sources of sustainable wood will include wood from trees (such as chestnut, hazel, willow and poplar) managed through coppicing. Coppicing involves cutting the tree back to near ground level every few years (how many depends on the species of tree). The tree then regenerates from the stumps that remain. Wood produced by coppicing is often chipped so it can be used in an automated boiler rather than a wood burning stove.

Wood sourced from tree surgeons can also be sustainable, because the work that they do can encourage new growth or allow new trees to be planted where an old one has been removed. The alternative, which is oftne landfilling is neither sustainable (because wood decaying in the absence of oxygen produces methane a stronger greenhouse gas than carbon dioxide) nor economically viable (because of the charges made to landfill). Using wood can therefore be a way to heat in a sustainable way.