Invercargill Prison's coal boiler will be upgraded to a more environmentally sustainable wood-fired boiler. In a bid to have a carbon neutral public sector by 2025, the Government is supporting organisations across the country to clean up their energy sources.

In the lower South Island this includes funding to assist in the upgrading of Invercargill Prison’s coal boiler with a more environmentally sustainable wood-fired boiler.

This and other Southern projects are part of a total funding announcement of $13.2 million from the Government’s $220 million State Sector Decarbonisation Fund. Corrections will receive $2.8m from the Climate funding pool to support this upgrade.

Project Manager Mike Suttill from the Asset Management team says there are currently two coal fired boilers at Invercargill providing most of the space heating and all of the water heating in the prison.

The upgrade will decommission the smaller 500 kW end of life (25-year-old) coal fired boiler and convert a larger 7-year old 1.700 kW coal fired boiler to run with wood pellets. Additionally, four of the six air handling heating units are being upgraded with additional electric coils. These improvements are expected to produce 18.5 tonnes of carbon emissions a year, resulting in carbon savings of up to 8,742 tonnes of carbon dioxide over 10 years.

“This means a 97.5% reduction on current emissions,” says Mike. “Not only is that a significant reduction in emissions, it also removes the last coal fired boiler from the Corrections estate.

“A temporary boiler will be installed during construction and we anticipate that this work will be completed and the wood pellet boiler commissioned and operational ahead of winter 2023.”

Mike says the wood pellets will be sourced from a local Invercargill based sawmill that produces a variety of timber products. With a vision to use 100% of timber logs, they produce wood pellet fuel from building materials production waste.