The effect of storage conditions on the natural drying of radiata for energy use
National energy policies increasingly support the use of forest biomass for energy supply due to its contribution to climate change mitigation, community welfare and local development. To help increase the efficiency of forest biomass, a University of Canterbury study researched the effect of storage duration and technique on the moisture content of radiata pine biomass logs in New Zealand.
Two trials were established in the South Island, with one stored in summer in a warm and dry location and the other in winter in a cold and relatively wet location. After 24 weeks in summer storage, the moisture content of radiata pine logs decreased from an initial value of 53% to between 33 and 21%. Logs stored in winter dried very little over a 17-week period.
The best summer storage technique was the simplest and consisted of stacking small logs without any cover. The larger logs dried the slowest, but splitting accelerated drying significantly. Covering did not help and results indicated that, while covering is useful for preventing rewetting of dry logs, it does not improve drying of wet logs.
Image credit: FIEA