Capture rate, contamination and compost quality are key to maximising Australia’s focus on FOGO. MRA Consulting Group’s Virginia Brunton and Cara Watters explain.
Perth, Adelaide, Victoria and now all New South Wales households will have Food Organics, Garden Organics (FOGO) collections by 2030.
These states are all seeing FOGO diversion as a means of achieving the national target of 80 per cent diversion from landfill by 2030, as well as achieving real greenhouse gas reductions. Tasmania and the ACT are also committed, and individual councils in Queensland are advancing FOGO.
Potentially, that’s six million tonnes of FOGO. The outcomes could be 3.6 million tonnes of compost; seven million tonnes less carbon dioxide emissions per year; 40,000 tonnes of carbon in soil and about 8000 new jobs.
But how do we make the most of this revolution in FOGO waste management. How do capture the most FOGO possible and deliver the best environmental outcomes? Capture rate, contamination and compost quality are the keys.
Capture rate
The best performing systems capture 98 per cent of available garden organics and more than 85 per cent of the available food waste. They do it with weekly 240L bin FOGO collections; fortnightly (140L or 240L) general waste collections; caddies and caddy liners; and consistent and engaging community education.
Analysis of the 2019-20 NSW Waste and Resource Recovery (NSW WARR) data shows that moving to a fortnightly general waste service can increase kerbside FOGO capture by 10 per cent compared to a weekly general waste service.
Along with certain bin configurations, providing liners can also improve food diversion.
Less than half of councils supply free caddy liners to their residents. MRA used the NSW WARR data to compare councils with the same bin configuration and the only difference being whether liners are provided (or encouraged). Councils with liners had on average 30 per cent more FOGO captured than those without. Not supplying caddy liners often comes down to cost.
It can cost about $1.5 million each year to supply liners for 100,000 households, however, it is worth considering the long-term savings.
MRA’s modelling shows the avoided landfill gate fees from the 30 per cent of additional food waste captured is $3.8 million. Considering additional FOGO processing costs, the liners ultimately result in an annual saving of $400,000.
Contamination
Compared with recycling, people know what FOGO waste is. Contamination tends to come from the use of non-compostable caddy liners.
The solution for this is the supply of free compostable caddy liners. This removes accidental contamination from resident confusion regarding ‘biodegradable’, ‘degradable’ and other labels on caddy liners in supermarkets.
Based on select councils within NSW and Victoria, caddy liners reduce contamination by about one per cent.
Much of the success of a FOGO system relies on the community being onboard and enthusiastic. A Victorian review of FOGO behaviour shows that 60 per cent of residents would use a kerbside FOGO bin. Of the remainder, 32 per cent sat on the fence and eight per cent said they wouldn’t use a FOGO bin.
MRA’s research shows that for every $1 increase in spend per household per year on education, contamination reduces by one per cent and capture rate increases by five per cent.
The compost market
Another often cited barrier to FOGO is that there is no market for compost. For high quality compost, this could not be further from the truth.
If the seven million tonnes of FOGO currently landfilled nationally was recovered and composted, it would result in 4.2 million tonnes of compost. If this was applied at the standard 10 tonne per hectare rate, it would only cover the area of Kangaroo Island.
Australia has 373 million hectares of agricultural land and two thirds of this is degraded by soil erosion, salinity, acidity, or contamination and all can benefit from the additional organic matter that compost can supply.
At the right price point, compost would be a no-brainer for farmers. Achieving a standard of compost that meets the price and quality expectations of agricultural users is the key.
MRA has developed contract clauses that include compost quality performance criteria and key performance indicators (KPIs) for councils. These clauses have been used in recent FOGO processing contracts in NSW and Queensland.
The KPIs go beyond AS4454 (the minimum voluntary compost standard) with reduced contamination thresholds and criteria to ensure a stable, mature, and fit-for-purpose compost. These extra criteria might cost a few cents more per household, but they ensure a high-quality compost for farmers and council itself.
Together these three elements; the right bin configuration, use of liners, and contracting compost quality, will go a long way to getting the best outcomes from FOGO systems.
For more information, contact info@mraconsulting.com.au
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