Wood a better option?
The company investigating using wood such as wilding conifers as heat sources for large energy users is asking organisations to complete a survey to help the research. Dunedin-based energy efficiency firm, Ahiki Consulting, and Otago Polytechnic’s Centre for Sustainable Practice have been commissioned by the Queenstown Lakes and Central Otago district councils and the Conservation Department to examine whether renewable wood could replace the traditional heating sources of coal, diesel and LPG. Queenstown Lakes district forester Briana Pringle said controlling wilding pines was expensive and using the wood waste for heating could offset the cost. Wood was already used to heat the Wanaka pool, but the chips were trucked from Naseby, despite the abundance of wilding conifers in the district. Ahika’s energy consultant Lloyd McGinty said Dunstan High School, Dunstan Hospital and Mt Difficulty and Rippon wineries also used wood burners. Commercial accommodation, laundromats and rest homes were other businesses which could benefit from switching to renewable wood boilers. ‘‘One of the main advantages is the low cost compared to LPG, diesel or electricity. Wood chip boilers can be up to 60 per cent cheaper to operate. ‘‘Developing a wood energy supply cluster is a chicken and egg scenario. Organisations are unlikely to invest in expensive wood boilers and associated infrastructure if the supply isn’t available and secure. Conversely, suppliers are unlikely to enter the market unless there’s reasonable demand for their product. Either way, someone has to be the first off the block.’’ Mt Difficulty’s general manager Matt Dicey said the winery had saved thousands of dollars a year since replacing its gas boiler with wood about four years ago. The infrastructure and installation had cost about $100,000 and had been partially funded by an Energy Efficiency and Conservation Authority grant. The winery’s gas boiler had heated the glycol, which controlled the fermenting temperatures and the rooms, and the gas bill had been about $10,000 a year. The wood burner also heated the water, with about $7000 spent on locally-sourced wood chips per annum. The winery’s annual production had more than doubled since the boiler was changed and Mr Dicey estimated the energy bill would have grown to about $25,000 a year had gas been used to heat the water. Using hot water to sterilise equipment had also reduced the amount the winery spent on chemicals. The anonymous survey focused on an organisation’s energy use and aimed to increase Ahika’s understanding of the potential interest in, and demand for, using wood energy.
Energy efficient: Mt Difficulty’s Matt Dicey says the winery is saving thousands a year on energy since replacing its gas heating system with a wood chip boiler.