New chipper key to HCU operation


2021-01-26T11:48:00 Pacific/Auckland

Tue 26 Jan 21


Council’s waste minimisation team are excited about taking delivery of a new chipper which is a key part of the infrastructure required for getting the Hot Composting Unit (HCU) being built at the Taumarunui Transfer Station fully operational.

Sustainability Educator Emily Jasmine said that chipped green and wood waste is a critical ingredient for making nutrient rich compost and we need a lot of it.

“The compost making process is fairly simple however we can’t just throw everything onto a pile and expect it to transform into a quality compost especially with the volumes we are making.

The recipe involves layering a lot of wood chips which provides carbon with the collected food scraps and green waste which provides nitrogen and turning it regularly to aerate while adding water,” she said.

“Although we are very thankful to local contractors Downers and Treescape who have dropped-off wood chips for use in the HCU from jobs they have done locally the volumes of chipped green and brown material needed means we need to be self-sufficient.

When fully operational we will be using a lot of green waste and wood chips and the on-site chipper will ensure we can keep up with the demands of the HCU.

Once construction of the HCU is complete it will have a sectioned, moveable roof to eliminate rain water and contain the heat which helps to speed up the decomposition process which takes around 12 weeks from raw ingredients to compost.

People dropping-off green waste at the Transfer Station can help by keeping any fibrous material such as flax - harakeke or cabbage tree – ti kouka leaves separate as we cannot use these in the HCU due to the time they take to break down.

Emily said that the new chipper was manufactured in Hamilton by HANSA and it was great to be able to purchase a NZ made unit which Council was hoping to help fund with a grant from the Ministry for the Environment (MFE) Waste Minimisation Fund.

“Anyone who wants a better understanding of Ruapehu’s waste minimisation plans and the Zero Waste 2040 vision including the role of food waste collection can get more info from Council’s website

There is also a great video on the HCU in Raglan which is what our HCU design is based on and provides an explanation of how it all works,” she said.


The new chipper will be key to keeping up with the volume of chipped green waste and wood waste needed for the Hot Composting Unit (HCU) when it is fully operational.

Page reviewed: 26 Jan 2021 11:48am