Why Forest Biomass Used to Produce Wood Energy is Carbon Neutral
The Carbon Zero Bill – the legislation that will guide New Zealand to becoming carbon neutral by 2050 – is now out for consultation Wood energy will play a vital role in helping New Zealand transition to a low-emissions future through conversions that replace fossil fuel use for heat and process energy.
It’s very simple to understand that coal, gas and diesel are high-carbon emitting pollutants – but why is forest biomass used to produce wood energy considered carbon neutral?
During their growth, trees absorb carbon from the atmosphere as CO2 and convert it into stored carbohydrates. So when you burn a tree, you’re only releasing the carbon that the tree had stored up, carbon that would have been released anyway when the tree died and decomposed.
About 15-20% of a tree is wasted in the forestry wood processing industry. This residue is going to turn into CO2 whether it is burned or allowed to rot.
Most New Zealand forests being logged for industrial purposes are radiata pine, which makes up 90% of the planted production forest area. These fast-growing exotics that rapidly uptake CO2, are grown as a crop and the waste, which can be used for wood energy, is part of a cycle of harvest and replanting.
The collection of wood waste from forestry sites has the collateral positive environmental impact of preventing erosion and damage to waterways. The replanting of forests enables more carbon to be absorbed from the atmosphere through tree growth and creates a carbon neutral cycle.