Reasons for investing in a biogas project

The key drivers for existing biogas plants in Queensland have been:

• reducing odours from abattoirs or rendering plants
• generating electricity for landfill sites, rendering plants and waste water treatment plants.

But investing in anaerobic digesters can also be justified to produce fertiliser, to increase water efficiency or to derive revenues from renewable electricity production.

Carbon pricing mechanism (CPM)

The rising costs of energy and potential liability under the carbon pricing mechanism (CPM) act as renewed incentives for some industries to consider processing their waste through anaerobic digestion.

While animal husbandry is not liable for its greenhouse gas emissions, associated industries, including abattoirs, rendering plants, food manufacturers and landfills, will fall under the obligations of the CPM. If they exceed the emission threshold, they will have to pay for emissions or look for ways to reduce and offset them.

Selling excess energy

The heat, steam or electricity produced from processing waste can be used on site to operate a business, which can offset part or all the cost of buying energy from the electricity network. Any surplus energy can be commercialised as green energy and sold back to the grid.

Facilities that want to generate part of their own power requirements and sell electricity surpluses will need to negotiate with electricity distribution network owners. Visit Ergon Energy's website for more information and enquiries about connecting a biogas business to the electricity distribution network.

Methane capture and carbon offsets

Methane (CH₄) is a greenhouse gas over 20 times more effective in trapping heat in the atmosphere than carbon dioxide (CO₂). As a result, efforts to prevent or use methane emissions can provide significant environmental benefits. Under the Australian Government's Renewable Energy Target and Carbon Farming Initiative, capture and processing of methane can generate carbon offsets with a commercial value on a carbon market.

To assist stakeholders in the meat and livestock industry investigate the potential of a methane capture project on their site, several questionnaires and self-assessment tools have been designed. For example, the AgriFutures Australia report Assessment of methane capture and use from the intensive livestock industry refers to a self-assessment tool created by Mattocks in 2003.