11 Dec 2019
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I was in Switzerland recently and discovered that they haven’t had any landfill since the early 2000s, because all of their waste is either recycled or incinerated to produce electricity. How “green” is it to incinerate waste in order to produce electricity? Is it something New Zealand should consider, so that 1) we have no more landfill, and 2) we can replace our fossil-fuel power stations with power stations that incinerate waste?
Burning rubbish to generate electricity or heat sounds great: you get rid of all your waste and also get seemingly “sustainable” energy. What could be better?
Many developed countries already have significant “waste-to-energy” incineration plants and therefore less material going to landfill (although the ash has to be landfilled). These plants often have recycling industries attached to them, so that only non-recyclables end up in the furnace. If it is this good, why the opposition?
Here are seven reasons why caution is needed when considering waste-to-energy incineration plants.
European countries were driven to waste-to-energy as a result of a 2007 directive that imposed heavy penalties for countries that did not divert waste from landfills. The easiest way for those countries to comply was to install waste-to-energy plants, which meant their landfill waste dropped dramatically.
New Zealand does not have these sorts of directives and is in a better position to work towards reducing, reusing and recycling end-of-life materials, rather than sending them to an incinerator to recover some of the energy used to make them.
Is New Zealand significantly worse than Europe in managing waste? About a decade ago, a delegation from Switzerland visited New Zealand Ministry for the Environment officials to compare progress in each of the waste streams. Both parties were surprised to learn that they had managed to divert roughly the same amount of waste from landfill through different routes.
This shows that it is important New Zealand doesn’t blindly follow the route other countries have used and hope for the same results. Such is the case for waste-to-energy.
There is also an argument to be made for current landfills. Modern, sanitary landfills seal hazardous materials and waste stored over the last 50 years presents future possibilities of landfill mining.
Many landfills have higher concentrations of precious metals, particularly gold, than mines and some are being mined for those metals. As resources become scarcer and prices increase, our landfills may become the mines of the future.
This opinion piece was first published on The Conversation.