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Green and organic waste

 

GreenGC picture Green & organic wastecompostable organic waste

Green waste comes from our gardens and includes things such as grass clippings, tree prunings and dry leaves.

In the natural world, green waste is constantly recycled by bacteria, worms, beetles, termites, plants and fungi.

When this waste is recycled (or decomposed) nutrients are released and used by growing plants; when a plant (or an animal that eats plants) dies, the cycle starts again - this is known as the nutrient cycle.

Research shows that more than half of the waste produced in our homes is organic - mainly food and garden waste. Some people recreate the nutrient cycle using a compost bin or worm farm, however any green or other organic waste placed in a domestic wheelie bin goes to landfill. Although this waste will eventually decompose, it will not provide nutrients for plants but will produce greenhouse gases such as methane.

Greenhouse gases released into the atmosphere act like a blanket, forming a layer that prevents some heat from the sun escaping into space. Many scientists think that the increasing production of greenhouse gases is making the earth hotter - this is known as global warming.

What can we do with our green waste to reduce these impacts?

 

GreenGC picture Managing organic waste on the Gold Coast

Gold Coast City Council has implemented a number of innovative strategies to reduce the volume of green waste going to landfill; one of these strategies mimics the nutrient cycle.

 

Green waste to compost

Garden waste - palm fronds, tree stumps and prunings dropped of at Council landfills and transfer stations is taken to Phoenix Power Recyclers for transformation into compost.

Phoenix Power Recyclers shreds the material and mixes it with biosolids, poultry manure, paper waste and grease trap waste. Once mixed it is formed into large composting piles called windrows. The windrows are turned to maintain oxygen levels and correct temperatures. Over time, through the action of bacteria and other organisms, the waste turns into a rich, dark brown compost material called humus. Council uses the humus on parks and gardens; it is also sold to nurseries and landscape gardeners.

GreenGC picture The Good Worm on Compost (1.2MB)

 

Green waste to energy

Some of the green garden waste delivered to Council facilities is used to produce renewable energy. At Rocky Point Cogeneration Plant at Woongoolba, green waste is combined with waste sugar cane material, called bagasse. This mix fuels large boilers that produces steam which then turns a turbine generator that produces electrical energy. The Rocky Point Sugar Mill uses this energy during the harvesting season. At other times, householders buy the electricity through Energex's Earth's Choice program.

Every year Rocky Point produces enough electricity to power 18,000 homes and prevents 130,000 tonnes of greenhouse gases entering the atmosphere.

The Rocky Point Cogeneration Plant uses over 200,000 tonnes of organic waste every year, which would otherwise go to landfill.

Using green waste for energy is a responsible way to reduce the production of greenhouse gases that would otherwise come from non-renewable power generation and the production of landfill gases.

In the year 2008 to 2009, over 70,000 tonnes of green waste was diverted from Council landfills and recycled or reused.

 

 

GreenGC picture Minimising organic waste at homeFood waste

We cannot build a power plant in our garden but we can recreate the nutrient cycle by using a compost bin or worm farm.

Composting or worm farming:

  • reduces the amount of waste going to landfill
  • produces a nutrient rich, natural fertiliser for your garden
  • helps to aerate the soil and improves moisture retention, saving you money on water costs
  • will help you to grow wonderful vegetables, flowers and plants.

 

GreenGC picture Related links

To find out how the Wipe Out Waste program can help your school to reduce the amount of organic waste please contact us.

For more information on starting your own compost bin or worm farm please click here.

The following Gold Coast City Council publication is full of great advice on why and how we can set up our own worm farm.

Next page: Litter-free schools - Print this page - Updated on: Friday 04-Jun-10