Harvest

The harvesting of trees and the production of wood materials requires less energy than other building materials, and is better for the environment.

Trees act like natural solar panels. Using sunlight, they absorb carbon dioxide and convert it to wood as they grow. Saw dust and wood waste is also collected and burnt as fuel to produce energy in sawmills through the processing stage, further reducing the need for fossil fuels. All this means that very little energy is required from fossil fuels in the manufacture of wood.

This has significant benefits for the environment, as the use of less fossil fuel in the harvesting and production process for wood results in less carbon dioxide emissions into the atmosphere than other energy-intensive building products.

Harvesting trees and producing wood materials uses less energy than the production of other materials such as steel and aluminium. Wood is also different to other materials in that it continues to store atmospheric carbon dioxide as a manufactured product, whereas materials such as steel and cement do not.

Embodied energy is the energy needed to manufacture building materials. For wood it includes the powering of forestry machinery, transportation of logs by logging trucks and saw mill manufacturing processes. For steel it involves high energy industrial smelting. The proportion of embodied energy that uses fossil fuels results in carbon dioxide emissions.

Many wood processing plants in New Zealand operate on-site heat and power plants fueled by wood residues from the harvesting and sawmilling process.

Wood used for fuel in heat and power plants in the production process has almost no effect on the net carbon dioxide balance in the atmosphere, as the carbon dioxide given off during burning has been recently removed from the atmosphere during the growing of the tree which produced the wood bioenergy fuel.