Fuelling the Future with Renewable Energy
Food scraps are not simply being diverted from landfill. They are being turned into a useful source of renewable energy.
When food scraps are sent to landfill, they break down and produce methane, a powerful greenhouse gas.
Instead, food scraps collected through MDC's kerbside service are currently transported to the Ecogas facility in Reporoa, where they are processed using anaerobic digestion.
What is anaerobic digestion?
Anaerobic digestion uses microorganisms to break down organic material in an environment without oxygen.
The process produces:
- biogas, which can be used to produce heat and renewable energy
- digestate, a nutrient-rich material that can be used as an agricultural fertiliser.
The Ecogas Reporoa facility currently provides biogas equivalent to the needs of around 7,200 New Zealand homes.
Why are food scraps transported to Reporoa?
Research by the Ministry for the Environment and international studies has compared the emissions created by transporting food scraps with the emissions avoided by keeping them out of landfill.
The analysis indicates that the emissions savings from anaerobic digestion outweigh transport emissions unless food scraps are transported more than approximately 5,000 kilometres.
You may also be interested to know that it is cheaper to send food scraps to Reporoa than it is to send to landfill!
What is MDC's long-term plan?
MDC's long-term goal is to process food scraps locally using anaerobic digestion at the Manawatū Resource Recovery Park in Feilding.
The wider renewable-energy project being explored with Powerco would allow organic material, including food scraps and other suitable waste streams, to be processed locally and used to generate renewable energy.
Until that local processing capability is available, collected food scraps will continue to be processed at Ecogas in Reporoa.
Why separate food scraps from rubbish?
Around 40% of the material found in Council blue rubbish bags is organic waste, with food scraps making up a significant proportion.
Separating food scraps:
- reduces the amount of waste sent to landfill
- reduces landfill methane emissions
- helps produce renewable energy
- may mean your household needs fewer Council blue rubbish bags.