Waste Management has been engaged in discussions and investigations regarding Waste to Energy (WtE) plants in New Zealand over many years.
In recent years, this discussion has focused on whether there are possible benefits that WtE (also known as waste incineration) could bring to complement existing waste infrastructure in New Zealand, to create a more sustainable approach to waste management.
WtE brings some benefits to communities in Europe where:
- there is a demand for additional or new sources of renewable energy to replace coal
- power is much more expensive than in NZ
- heating for reticulated hot water to adjacent urban areas is needed (which can be provided centrally by a local WtE plant)
- governments can use legislative power to protect WtE plants from competition
- governments are prepared to subsidise WtE plants
- populations are large and dense and create a large amount of waste
- waste can be imported from other countries for the operation of WtE plants
- road and rail transport networks are well developed, and
- land is scarce and expensive (rendering landfills problematic for the volumes of waste being created).
In New Zealand, the Government has not supported widespread investment in WtE as the community benefits above are not as evident.
In particular, to deliver adequate return on the investment in WtE plants, a guaranteed specific volume of continual waste (often including potentially recyclable materials) is needed for efficient operation of the plant – without that ongoing volume over several decades, the WtE plant will not be financially or operationally sustainable. This is generally called the “feed the beast” effect, and it does not support New Zealand’s goals as stated in the Waste Minimisation Act, namely to “encourage waste minimisation and a decrease in waste disposal”.
In Waste Management’s experience, our investigations globally, including in Australia, China, and across Europe, indicate the costs associated with WtE are significantly higher than current methods of waste disposal to landfill. As such, were WtE to be of consideration, it would need government intervention (that is, government protection for these facilities) as there is in European and other countries, to make it a viable proposition for commercial investment.
Were the New Zealand government interested in this approach, Waste Management would leverage the significant experience of our parent company, which owns and operates several WtE plants in China. These plants service large populations of around 10 million people within one city. In these cities, government regulation stops alternative, potentially cheaper, disposal solutions being built and government subsidies make the WtE disposal costs affordable for the community.
Other factors to consider in relation to WtE
- Carbon emission impact: WtE is often considered a solution for managing municipal waste streams, which contain a considerable amount of plastic. All plastic is made of carbon – either carbon derived from oil or carbon derived from natural materials (such as plant-based “bioplastics”). Burning plastics in an incinerator means you are burning the carbon captured in the plastics. Any emissions from burning this carbon in a WtE plant will impact on New Zealand’s carbon footprint and also impact our progress towards achieving the targets agreed to in the Paris Agreement.
- Managing ash: WtE works by incinerating all waste, resulting in an ash that is a toxic substance containing high concentrations of hazardous materials such as heavy metals. This needs to be disposed of in an environmentally safe manner (usually a modern and specifically designed hazardous waste landfill). The concentrations of contaminants would likely exceed the waste acceptance criteria specified for New Zealand landfills.
- Renewable energy demand: New Zealand has existing, available renewable energy sources in geothermal and hydro generation. In fact, 86% of our electricity comes from renewable sources. This means that, unlike Europe, there is limited demand for additional renewable energy generation.
- Air discharge management: There are discharges of contaminants into the air from the burning of waste at WtE plants. These require careful management and monitoring of potential airborne pollution. The equipment to manage these discharges effectively often makes up a majority of the high capital and operating costs of WtE facilities and would be fully expected in a New Zealand WtE plant.
- Transportation impact: New Zealand’s population is small by international standards, and just one small WtE plant would be needed to manage all of our