NZ: Waste converted to energy

A New Zealand energy consultant says a technology which converts any kind of waste to renewable energy could be the way forward in making the Pacific region more sustainable.

Otago Polytechnic’s Neville Auton will present to the United Nations Small Islands Developing States conference in Apia next month on the logistics and benefits of the technology, called pyrolysis.

Auton said the process uses pyrolysis, which is high temperature, to break rubbish down to its organic components.

“Down to hydrogen components, which basically create a synthetic gas, which you can then use to run gas engines, turbines, so you’re basically converting the waste stream into an energy form, a gas form,” he said.” There are some bi-products out of the process, an ash type product.

“The visit to Samoa is really to look at what is the potential for that sort of technology in the islands and whether the waste stream is large enough to support that sort of technology, and whether there is any integration with the other islands that are possible as well – so that we can actually bring waste from other islands for a process of generation.

He said the process deals with all types of rubbish.

“This will take any type of rubbish other than metals and glass basically. So it can take plastics. Plastics are effectively a petroleum product so they will turn to a gas at suitable temperatures and break down the long carbon chains into small carbon chains.

He said the technology is currently being used in Germany and a few other places around the world.

“It’s been about and been proven for quite a while. This is the next step from incineration.It’s really high temperatures and high temperature plasma, which actually breaks it down to initial components of construction within the products.

So how much would this cost for a Pacific Island nation to get these systems up and running?

“Probably in the order of 20 million dollars,” Auton said. “Some of them up to 50 million dollars. It all depends on the size of course, and what the potential is.

“Samoa for instance is about 60 per cent diesel electricity generation so this is looking to remove the diesel component out of the energy generation system going to more renewable energy.

“So part of that will be photovoltaic, wind, wave energy perhaps, but it’s really looking at what are the potentials for the waste.

“Is there product manufacture opportunities out of that waste, to generate local employment, and improve sustainability within the islands, and having positive sustainability outcomes is really part of the process.

“A lot of these small islands have exactly the same issues, that they are relying on diesel for generation and the cost of diesel.

“Because they are at the end of the supply chain as well, if there are any issues in regard to shortage of diesel in the future or anything like that. Then it places them at great risk from an electricity generation point of view.

“We’ll be looking at biomass as well, so we may be able to convert for example coconut husks and outer material into gas which you can use in the generator. So you get a local product that’s actually generating an energy product.”