HotRot Green Waste Composting System

May 2019 saw the installation of a HotRot in-vessel composting system at the Kangaroo Island Resource Recovery Centre (KIRRC), similar to those in use on Lord Howe Island and the Melbourne Zoo.

Composting all Food Organics and Green Organics (FOGO) on the Island - using the HotRot system - delivers a number of benefits, particularly if we further improve the amount of waste we divert from the red bin (which goes to landfill) to the green bin (which can ultimately be used as mulch).

The benefits include:

  • Cost savings Currently 33% of the cost of waste management and collection on Kangaroo Island relates to the transport and disposal of waste into landfill on the mainland – better diversion of FOGO to the green bins will reduce these costs.
  • Retention On Island composting means valuable compost material can be retained here for domestic and primary production use.
  • Environmental There are significant environmental benefits in diverting organic waste material away from landfill, especially considering 40-100kg of methane is produced for every tonne of waste going into landfill for disposal.

The case for on-Island composting arose in a review conducted in 2017-2018 by Kangaroo Island Council (KIC) and the Fleurieu Regional Waste Authority (FRWA) of waste management practices on Kangaroo Island, identifying the need for significant changes and improvements to the processing of recyclable waste materials, including dry recycling (cardboard, paper, hard plastic and glass) and FOGO on the Island.  The review also led to the introduction of kerbside green organics collection to 12 townships and coastal settlements, and fortnightly collection of all three waste streams.

FRWA was successful in two funding applications to Green Industries SA which resulted in the installation of:

  • a baler at the KIRRC for dry recyclables, allowing for sorted loads (instead of combined) to be transported off Island
  • an in-vessel composting system at the KIRRC.

Together these initiatives will improve the efficiency of the Island's waste management services, adding to the Island’s reputation for environmental management and sustainability.

For more information about the HotRot in-vessell system, click here.

How households can help ...

Bin audits conducted by Fleurieu Regional Waste Authority (FRWA) have shown that residents within the FRWA collection area were filling 44% of their general waste bins with food organics and compostable paper. This is sent direct to landfill, with resultant costs and no benefit to the environment.

When Kangaroo Island residents divert food waste and compostable paper to the green bins, this waste can be processed in the HotRot in-vessell system at the KIRCC and be converted into valuable mulch for the Island.

The key to increasing your household’s FOGO is to use a kitchen caddy in your kitchen food preparation area.

All kitchen food organics, including plate scrapings can be placed in the kitchen caddy ready for disposal in the green organics bin, including:

  • Fruit and vegetable peelings
  • Meat and bones
  • Poultry and seafood
  • Baked goods – bread, cakes and pastries
  • Tea bags and coffee grounds
  • Eggshells, pasta, rice and dairy products
  • Paper and cardboard including pizza boxes
  • Uneaten takeaway food
Kitchen Caddy

Kitchen caddies and compostable bags are available for purchase from Kangaroo Island Council. For a short time, households are able to purchase a kitchen caddy (which comes with a roll of compostable bags) and a second roll of compostable bags at a 50% discounted rate.

Compostable Bags are used as caddy liners and can be tied at the top to contain food organics before disposal in the green organics bin. Compostable bags break down in the presence of heat, moisture and oxygen leaving no toxic residue.

VERY IMPORTANT: Please DO NOT put plastic bags into the green bin - plastic bags, even those marked as biodegradable or degradable merely break down into smaller pieces of plastic. They are not compostable.

For more information, download the FRWA FOGO Fact Sheet from here.

Businesses and FOGO

FRWA has been working with a number of Kangaroo Island businesses, running a trial aimed at encouraging businesses to divert waste from landfill.

For articles about this trial by The Islander:

  • Introducing the trial program click here.
  • Reporting on the progress of the trial click here.
Kangaroo Island Council | 43 Dauncey St (PO Box 121) KINGSCOTE SA 5223
Phone: 08 8553 4500 | Fax: 08 8553 2885 | Email:
Kangaroo Island Weather