With their rubber soles, leather body and (probably) organic cotton laces, they are the perfect embodiment of the waste management crossroads at which Canberra now finds itself.

You can’t recycle sneakers, and they can’t be turned into compost. While their individual components could well be individually harvested and recycled, separating them would be too labour-intensive.

And so, they go to landfill. We put them in the red bin, and never think of them again.

But those shoes have other things they could be doing. They could actually still be useful - incinerated to produce a gas, or crushed into pellets to replace fossil fuels. They could, in other words, be used to create energy.

Canberra is doing pretty well when it comes to what happens to our waste, but we’re still not on track to meet our 2025 target of 90 per cent resource recovery.

Although our aspiration is admirable - one of the highest targets in the country - we’re still hovering around 70 per cent - still pretty good, second only to South Australia.

The ACT government’s recent Waste Feasibility Study, published in May, determined that with a few initiatives, we could get to 87 per cent resource recovery sooner than we think.

According to the City Services Directorate, Canberra currently generates a million tonnes of waste each year, about half of which comes from construction demolition - materials that have a high resource recovery rate of up to 90 per cent. The other 50 per cent is split between household waste, and commercial and industrial waste, which has a resource recovery rate of almost 60 per cent.

So what to do with all the dirty cardboard, used nappies, filmy plastics, timber fragments and the aforementioned old sneakers that are currently in limbo?

As well as the possibility of an expanded green-bin service that could take food as well as garden waste, dispensing with another 10 per cent of our waste, one of the main initiatives proposed is some form of waste-to-energy processing, either in the form of burning rubbish or converting it to fuel.

It’s done all over the world already, particularly in Europe and Asia, but Australia has been remarkably slow to latch on to the waste-to-energy bandwagon. Australia doesn’t have an issue with lack of space for landfill, nor do we demand extra energy to heat our homes in winter, like they do in Europe. Still, from the outside at least, it might seem puzzling that a city like Canberra has yet to develop an official policy on the matter.

According to Greg Haraldson, of the government’s recycling arm ACT NOWaste, the concept of waste-to-energy facilities in Canberra has had “a bit of a lukewarm reception” since it was put forth as one of the main solutions to our waste woes.

“What we're saying to the community is, with a food and garden organic service, and some other industry development work to make sure we get those metals and things that are going to landfill out of there, we can get to 80 per cent,” he says.

“But beyond that, to get world's best practice is going to be really difficult unless we start to look at either burning waste for energy or converting it to biochar.”

To this end, city services minister Chris Steele recently opened the issue up for public consultation, calling on Canberrans to help the government develop an official waste-to-energy policy.

To date, the closest we’ve come to any extended public engagement in the matter has been when the local community and the ACT Greens opposed a proposed waste-burning facility in Fyshwick earlier this year.

Part of the problem, according to developers Canberra Recycling Solutions, was that Canberra had no energy-to-waste policy in place.

As with many public consultation processes, it’s hoped that Canberrans of all stripes will emerge to have their say, a process that, according to senior manager in City Services Lisa Johnson, who is running the consultation, has proved surprisingly useful in the past.

“The Canberra community is a relatively educated community,” she says.

“We had an information session last night, and actually we found it really, really useful. I think people do have some preconceived notions about waste to energy, but they were prepared to read the information paper and have a proper conversation about it, and I think because it crosses such a large scale, from burning to composting, there is a lot there to talk about. It's not just incineration - there are a range of different technologies.”

Industry, on the other hand, is primed and ready for Canberra to board the waste-to-energy train; Haraldson says that in a recent market sounding, in which NOWaste asked members of the industry for suggestions on how to get from 70 to 90 per cent resource recovery, “about half the submissions that came forward were from companies looking to set up waste to energy facilities”.

“That's another indication to us that industry sees the ACT as open for business for waste to energy, potentially,” he says.

The consultation information paper lists six main waste-to-energy processes, all of which have been tried and tested elsewhere, including in Australia.

Incineration - the one most people think of in relation to waste to energy - involves burning waste to generate steam and ash. It’s a process used in many densely populated countries, especially in Europe, often within 500 metres of homes, and often to generate heat. Incineration plants use filters and scrubbers to remove regulated substances, and emissions are strictly monitored.

Chani Lokuge, who is technical director of waste management at AECOM, a multi-national engineering firm that has worked with the ACT government in the past, says converting residual waste to renewable energy would definitely be a suitable option for Australia, even for Canberra, given “the right market drivers and regulatory policies in place for it to happen”.

But he says the uncertainty around the concept of burning waste is understandable.

“I think there's room for more understanding about how these technologies work and how they've been adopted overseas successfully in dense urban environments,” he says.

But both Lokuge and Haraldson point out that, in a city as small as Canberra, there will also be an issue with economies of scale; infrastructure for waste incineration is expensive and immovable. It also needs to be fed - “feeding the beast” is a an industry-wide concern - and this could, in theory, encourage more waste.

Another heat-related process involves the gasification of waste, a technique that’s been used as early as World War II to fuel vehicles from wood. The infrastructure would be cheaper than incineration, with fewer emissions, but the technology is probably not commercially developed enough to be viable for the ACT.

Pyrolosis, where biomass is heated in very low oxygen environments to produce a solid residue with a high concentration of carbon (char), is another option for waste generation. But, like anaerobic digestion - the breakdown of organic materials to produce a biogas - it’s a process that relies on organic or biodegradable waste.

Canberra's main landfill at Mugga Lane is already producing methane - enough to power around 3000 houses, in fact - but there’s still significant methane leakage involved (around 30 per cent), and the process still requires landfill in the first place.

Possibly the most feasible waste-to-energy process for the ACT would be the creation of refuse-derived fuel, which involves a simple mechanical process of sorting, crushing and shredding waste and producing pellets. These can be used to fuel cement kilns elsewhere in the country - including nearby Berrima - in the place of fossil fuels. It would also require far less investment than incineration infrastructure, and wouldn’t involve emissions in the ACT.

“You don't actually need to heat it or burn it to create the fuel product, but it does go into an end-burning process,” Johnson says.

“So we don't call that a thermal technology, because you're not heating to create it. Interestingly, this is the one that, based on the waste feasibility study, has the potential for this possibly to take us from 80 per cent resource recovery to 87 per cent.

So that obviously requires some more research, but it is potentially a favourable option in the community.”

Lokuge says Canberra, with its single government and relatively streamlined bureaucracy, is in a good position to look at energy from waste to off-set the power demands of local industries in-line with the concept of a circular economy - converting what was a waste going to landfill into a valuable resource.

“But the community needs to be brought on board in the process,” he says.

Consultation for the ACT's waste-to-energy policy closes November 2018.